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| FFmpeg Codecs Documentation |
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| FFmpeg Codecs Documentation |
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| <h2 class="contents-heading">Table of Contents</h2> |
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| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Description" href="#Description">1 Description</a></li> |
| <li><a id="toc-Codec-Options" href="#Codec-Options">2 Codec Options</a></li> |
| <li><a id="toc-Decoders" href="#Decoders">3 Decoders</a></li> |
| <li><a id="toc-Video-Decoders" href="#Video-Decoders">4 Video Decoders</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-av1" href="#av1">4.1 av1</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options" href="#Options">4.1.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-hevc" href="#hevc">4.2 hevc</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-1" href="#Options-1">4.2.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-rawvideo" href="#rawvideo">4.3 rawvideo</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-2" href="#Options-2">4.3.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libdav1d" href="#libdav1d">4.4 libdav1d</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-3" href="#Options-3">4.4.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libdavs2" href="#libdavs2">4.5 libdavs2</a></li> |
| <li><a id="toc-libuavs3d" href="#libuavs3d">4.6 libuavs3d</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-4" href="#Options-4">4.6.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libxevd" href="#libxevd">4.7 libxevd</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-5" href="#Options-5">4.7.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-QSV-Decoders" href="#QSV-Decoders">4.8 QSV Decoders</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Common-Options" href="#Common-Options">4.8.1 Common Options</a></li> |
| <li><a id="toc-HEVC-Options" href="#HEVC-Options">4.8.2 HEVC Options</a></li> |
| </ul></li> |
| <li><a id="toc-v210" href="#v210">4.9 v210</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-6" href="#Options-6">4.9.1 Options</a></li> |
| </ul></li> |
| </ul></li> |
| <li><a id="toc-Audio-Decoders" href="#Audio-Decoders">5 Audio Decoders</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-ac3" href="#ac3">5.1 ac3</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-AC_002d3-Decoder-Options" href="#AC_002d3-Decoder-Options">5.1.1 AC-3 Decoder Options</a></li> |
| </ul></li> |
| <li><a id="toc-flac-1" href="#flac-1">5.2 flac</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-FLAC-Decoder-options" href="#FLAC-Decoder-options">5.2.1 FLAC Decoder options</a></li> |
| </ul></li> |
| <li><a id="toc-ffwavesynth" href="#ffwavesynth">5.3 ffwavesynth</a></li> |
| <li><a id="toc-libcelt" href="#libcelt">5.4 libcelt</a></li> |
| <li><a id="toc-libgsm" href="#libgsm">5.5 libgsm</a></li> |
| <li><a id="toc-libilbc" href="#libilbc">5.6 libilbc</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-7" href="#Options-7">5.6.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libmpeghdec" href="#libmpeghdec">5.7 libmpeghdec</a></li> |
| <li><a id="toc-libopencore_002damrnb" href="#libopencore_002damrnb">5.8 libopencore-amrnb</a></li> |
| <li><a id="toc-libopencore_002damrwb" href="#libopencore_002damrwb">5.9 libopencore-amrwb</a></li> |
| <li><a id="toc-libopus" href="#libopus">5.10 libopus</a></li> |
| </ul></li> |
| <li><a id="toc-Subtitles-Decoders" href="#Subtitles-Decoders">6 Subtitles Decoders</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-libaribb24" href="#libaribb24">6.1 libaribb24</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-libaribb24-Decoder-Options" href="#libaribb24-Decoder-Options">6.1.1 libaribb24 Decoder Options</a></li> |
| </ul></li> |
| <li><a id="toc-libaribcaption" href="#libaribcaption">6.2 libaribcaption</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-libaribcaption-Decoder-Options" href="#libaribcaption-Decoder-Options">6.2.1 libaribcaption Decoder Options</a></li> |
| <li><a id="toc-libaribcaption-decoder-usage-examples" href="#libaribcaption-decoder-usage-examples">6.2.2 libaribcaption decoder usage examples</a></li> |
| </ul></li> |
| <li><a id="toc-dvbsub" href="#dvbsub">6.3 dvbsub</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-8" href="#Options-8">6.3.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-dvdsub" href="#dvdsub">6.4 dvdsub</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-9" href="#Options-9">6.4.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libzvbi_002dteletext" href="#libzvbi_002dteletext">6.5 libzvbi-teletext</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-10" href="#Options-10">6.5.1 Options</a></li> |
| </ul></li> |
| </ul></li> |
| <li><a id="toc-Encoders" href="#Encoders">7 Encoders</a></li> |
| <li><a id="toc-Audio-Encoders" href="#Audio-Encoders">8 Audio Encoders</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-aac" href="#aac">8.1 aac</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-11" href="#Options-11">8.1.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-ac3-and-ac3_005ffixed" href="#ac3-and-ac3_005ffixed">8.2 ac3 and ac3_fixed</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-AC_002d3-Metadata" href="#AC_002d3-Metadata">8.2.1 AC-3 Metadata</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Metadata-Control-Options" href="#Metadata-Control-Options">8.2.1.1 Metadata Control Options</a></li> |
| <li><a id="toc-Downmix-Levels" href="#Downmix-Levels">8.2.1.2 Downmix Levels</a></li> |
| <li><a id="toc-Audio-Production-Information" href="#Audio-Production-Information">8.2.1.3 Audio Production Information</a></li> |
| <li><a id="toc-Other-Metadata-Options" href="#Other-Metadata-Options">8.2.1.4 Other Metadata Options</a></li> |
| </ul></li> |
| <li><a id="toc-Extended-Bitstream-Information" href="#Extended-Bitstream-Information">8.2.2 Extended Bitstream Information</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Extended-Bitstream-Information-_002d-Part-1" href="#Extended-Bitstream-Information-_002d-Part-1">8.2.2.1 Extended Bitstream Information - Part 1</a></li> |
| <li><a id="toc-Extended-Bitstream-Information-_002d-Part-2" href="#Extended-Bitstream-Information-_002d-Part-2">8.2.2.2 Extended Bitstream Information - Part 2</a></li> |
| </ul></li> |
| <li><a id="toc-Other-AC_002d3-Encoding-Options" href="#Other-AC_002d3-Encoding-Options">8.2.3 Other AC-3 Encoding Options</a></li> |
| <li><a id="toc-Floating_002dPoint_002dOnly-AC_002d3-Encoding-Options" href="#Floating_002dPoint_002dOnly-AC_002d3-Encoding-Options">8.2.4 Floating-Point-Only AC-3 Encoding Options</a></li> |
| </ul></li> |
| <li><a id="toc-flac-2" href="#flac-2">8.3 flac</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-12" href="#Options-12">8.3.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-opus" href="#opus">8.4 opus</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-13" href="#Options-13">8.4.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libfdk_005faac" href="#libfdk_005faac">8.5 libfdk_aac</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-14" href="#Options-14">8.5.1 Options</a></li> |
| <li><a id="toc-Examples" href="#Examples">8.5.2 Examples</a></li> |
| </ul></li> |
| <li><a id="toc-liblc3" href="#liblc3">8.6 liblc3</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-15" href="#Options-15">8.6.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libmp3lame-1" href="#libmp3lame-1">8.7 libmp3lame</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-16" href="#Options-16">8.7.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libopencore_002damrnb-1" href="#libopencore_002damrnb-1">8.8 libopencore-amrnb</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-17" href="#Options-17">8.8.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libopus-1" href="#libopus-1">8.9 libopus</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Option-Mapping" href="#Option-Mapping">8.9.1 Option Mapping</a></li> |
| </ul></li> |
| <li><a id="toc-libshine-1" href="#libshine-1">8.10 libshine</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-18" href="#Options-18">8.10.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libtwolame" href="#libtwolame">8.11 libtwolame</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-19" href="#Options-19">8.11.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libvo_002damrwbenc" href="#libvo_002damrwbenc">8.12 libvo-amrwbenc</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-20" href="#Options-20">8.12.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libvorbis" href="#libvorbis">8.13 libvorbis</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-21" href="#Options-21">8.13.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-mjpeg" href="#mjpeg">8.14 mjpeg</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-22" href="#Options-22">8.14.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-wavpack" href="#wavpack">8.15 wavpack</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-23" href="#Options-23">8.15.1 Options</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Shared-options" href="#Shared-options">8.15.1.1 Shared options</a></li> |
| <li><a id="toc-Private-options" href="#Private-options">8.15.1.2 Private options</a></li> |
| </ul></li> |
| </ul></li> |
| </ul></li> |
| <li><a id="toc-Video-Encoders" href="#Video-Encoders">9 Video Encoders</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-a64_005fmulti_002c-a64_005fmulti5" href="#a64_005fmulti_002c-a64_005fmulti5">9.1 a64_multi, a64_multi5</a></li> |
| <li><a id="toc-Cinepak" href="#Cinepak">9.2 Cinepak</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-24" href="#Options-24">9.2.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-ffv1-1" href="#ffv1-1">9.3 ffv1</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-25" href="#Options-25">9.3.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-GIF" href="#GIF">9.4 GIF</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-26" href="#Options-26">9.4.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-Hap" href="#Hap">9.5 Hap</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-27" href="#Options-27">9.5.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-jpeg2000" href="#jpeg2000">9.6 jpeg2000</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-28" href="#Options-28">9.6.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-librav1e" href="#librav1e">9.7 librav1e</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-29" href="#Options-29">9.7.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libaom_002dav1" href="#libaom_002dav1">9.8 libaom-av1</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-30" href="#Options-30">9.8.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-liboapv" href="#liboapv">9.9 liboapv</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-31" href="#Options-31">9.9.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libsvtav1" href="#libsvtav1">9.10 libsvtav1</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-32" href="#Options-32">9.10.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libsvtjpegxs" href="#libsvtjpegxs">9.11 libsvtjpegxs</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-33" href="#Options-33">9.11.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libjxl" href="#libjxl">9.12 libjxl</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-34" href="#Options-34">9.12.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libkvazaar" href="#libkvazaar">9.13 libkvazaar</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-35" href="#Options-35">9.13.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libopenh264" href="#libopenh264">9.14 libopenh264</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-36" href="#Options-36">9.14.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libtheora" href="#libtheora">9.15 libtheora</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-37" href="#Options-37">9.15.1 Options</a></li> |
| <li><a id="toc-Examples-1" href="#Examples-1">9.15.2 Examples</a></li> |
| </ul></li> |
| <li><a id="toc-libvpx" href="#libvpx">9.16 libvpx</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-38" href="#Options-38">9.16.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libvvenc" href="#libvvenc">9.17 libvvenc</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Supported-Pixel-Formats" href="#Supported-Pixel-Formats">9.17.1 Supported Pixel Formats</a></li> |
| <li><a id="toc-Options-39" href="#Options-39">9.17.2 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libwebp" href="#libwebp">9.18 libwebp</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Pixel-Format" href="#Pixel-Format">9.18.1 Pixel Format</a></li> |
| <li><a id="toc-Options-40" href="#Options-40">9.18.2 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libx264_002c-libx264rgb" href="#libx264_002c-libx264rgb">9.19 libx264, libx264rgb</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Supported-Pixel-Formats-1" href="#Supported-Pixel-Formats-1">9.19.1 Supported Pixel Formats</a></li> |
| <li><a id="toc-Options-41" href="#Options-41">9.19.2 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libx265" href="#libx265">9.20 libx265</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-42" href="#Options-42">9.20.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libxavs2" href="#libxavs2">9.21 libxavs2</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-43" href="#Options-43">9.21.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libxeve" href="#libxeve">9.22 libxeve</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-44" href="#Options-44">9.22.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-libxvid" href="#libxvid">9.23 libxvid</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-45" href="#Options-45">9.23.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-MediaCodec" href="#MediaCodec">9.24 MediaCodec</a></li> |
| <li><a id="toc-MediaFoundation" href="#MediaFoundation">9.25 MediaFoundation</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-46" href="#Options-46">9.25.1 Options</a></li> |
| <li><a id="toc-Examples-2" href="#Examples-2">9.25.2 Examples</a></li> |
| </ul></li> |
| <li><a id="toc-Microsoft-RLE" href="#Microsoft-RLE">9.26 Microsoft RLE</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-47" href="#Options-47">9.26.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-mpeg2" href="#mpeg2">9.27 mpeg2</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-48" href="#Options-48">9.27.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-png" href="#png">9.28 png</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-49" href="#Options-49">9.28.1 Options</a></li> |
| <li><a id="toc-Private-options-1" href="#Private-options-1">9.28.2 Private options</a></li> |
| </ul></li> |
| <li><a id="toc-ProRes" href="#ProRes">9.29 ProRes</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Private-Options-for-prores_002dks" href="#Private-Options-for-prores_002dks">9.29.1 Private Options for prores-ks</a></li> |
| <li><a id="toc-Speed-considerations" href="#Speed-considerations">9.29.2 Speed considerations</a></li> |
| </ul></li> |
| <li><a id="toc-QSV-Encoders" href="#QSV-Encoders">9.30 QSV Encoders</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Ratecontrol-Method" href="#Ratecontrol-Method">9.30.1 Ratecontrol Method</a></li> |
| <li><a id="toc-Global-Options-_002d_003e-MSDK-Options" href="#Global-Options-_002d_003e-MSDK-Options">9.30.2 Global Options -> MSDK Options</a></li> |
| <li><a id="toc-Common-Options-1" href="#Common-Options-1">9.30.3 Common Options</a></li> |
| <li><a id="toc-Runtime-Options" href="#Runtime-Options">9.30.4 Runtime Options</a></li> |
| <li><a id="toc-H264-options" href="#H264-options">9.30.5 H264 options</a></li> |
| <li><a id="toc-HEVC-Options-1" href="#HEVC-Options-1">9.30.6 HEVC Options</a></li> |
| <li><a id="toc-MPEG2-Options" href="#MPEG2-Options">9.30.7 MPEG2 Options</a></li> |
| <li><a id="toc-VP9-Options" href="#VP9-Options">9.30.8 VP9 Options</a></li> |
| <li><a id="toc-AV1-Options" href="#AV1-Options">9.30.9 AV1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-snow" href="#snow">9.31 snow</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-50" href="#Options-50">9.31.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-VAAPI-encoders" href="#VAAPI-encoders">9.32 VAAPI encoders</a></li> |
| <li><a id="toc-vbn" href="#vbn">9.33 vbn</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-51" href="#Options-51">9.33.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-vc2" href="#vc2">9.34 vc2</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-52" href="#Options-52">9.34.1 Options</a></li> |
| </ul></li> |
| </ul></li> |
| <li><a id="toc-Subtitles-Encoders" href="#Subtitles-Encoders">10 Subtitles Encoders</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-dvbsub-1" href="#dvbsub-1">10.1 dvbsub</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-53" href="#Options-53">10.1.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-dvdsub-1" href="#dvdsub-1">10.2 dvdsub</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-54" href="#Options-54">10.2.1 Options</a></li> |
| </ul></li> |
| <li><a id="toc-lrc" href="#lrc">10.3 lrc</a> |
| <ul class="toc-numbered-mark"> |
| <li><a id="toc-Options-55" href="#Options-55">10.3.1 Options</a></li> |
| </ul></li> |
| </ul></li> |
| <li><a id="toc-See-Also" href="#See-Also">11 See Also</a></li> |
| <li><a id="toc-Authors" href="#Authors">12 Authors</a></li> |
| </ul> |
| </div> |
| </div> |
|
|
| <a name="Description"></a> |
| <h2 class="chapter">1 Description<span class="pull-right"><a class="anchor hidden-xs" href="#Description" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Description" aria-hidden="true">TOC</a></span></h2> |
|
|
| <p>This document describes the codecs (decoders and encoders) provided by |
| the libavcodec library. |
| </p> |
|
|
| <a class="anchor" id="codec_002doptions"></a><a name="Codec-Options"></a> |
| <h2 class="chapter">2 Codec Options<span class="pull-right"><a class="anchor hidden-xs" href="#Codec-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Codec-Options" aria-hidden="true">TOC</a></span></h2> |
|
|
| <p>libavcodec provides some generic global options, which can be set on |
| all the encoders and decoders. In addition, each codec may support |
| so-called private options, which are specific for a given codec. |
| </p> |
| <p>Sometimes, a global option may only affect a specific kind of codec, |
| and may be nonsensical or ignored by another, so you need to be aware |
| of the meaning of the specified options. Also some options are |
| meant only for decoding or encoding. |
| </p> |
| <p>Options may be set by specifying -<var class="var">option</var> <var class="var">value</var> in the |
| FFmpeg tools, or by setting the value explicitly in the |
| <code class="code">AVCodecContext</code> options or using the <samp class="file">libavutil/opt.h</samp> API |
| for programmatic use. |
| </p> |
| <p>The list of supported options follow: |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">b <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt> |
| <dd><p>Set bitrate in bits/s. Default value is 200K. |
| </p> |
| </dd> |
| <dt><samp class="option">ab <var class="var">integer</var> (<em class="emph">encoding,audio</em>)</samp></dt> |
| <dd><p>Set audio bitrate (in bits/s). Default value is 128K. |
| </p> |
| </dd> |
| <dt><samp class="option">bt <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set video bitrate tolerance (in bits/s). In 1-pass mode, bitrate |
| tolerance specifies how far ratecontrol is willing to deviate from the |
| target average bitrate value. This is not related to min/max |
| bitrate. Lowering tolerance too much has an adverse effect on quality. |
| </p> |
| </dd> |
| <dt><samp class="option">flags <var class="var">flags</var> (<em class="emph">decoding/encoding,audio,video,subtitles</em>)</samp></dt> |
| <dd><p>Set generic flags. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">mv4</samp>’</dt> |
| <dd><p>Use four motion vector by macroblock (mpeg4). |
| </p></dd> |
| <dt>‘<samp class="samp">qpel</samp>’</dt> |
| <dd><p>Use 1/4 pel motion compensation. |
| </p></dd> |
| <dt>‘<samp class="samp">loop</samp>’</dt> |
| <dd><p>Use loop filter. |
| </p></dd> |
| <dt>‘<samp class="samp">qscale</samp>’</dt> |
| <dd><p>Use fixed qscale. |
| </p></dd> |
| <dt>‘<samp class="samp">pass1</samp>’</dt> |
| <dd><p>Use internal 2pass ratecontrol in first pass mode. |
| </p></dd> |
| <dt>‘<samp class="samp">pass2</samp>’</dt> |
| <dd><p>Use internal 2pass ratecontrol in second pass mode. |
| </p></dd> |
| <dt>‘<samp class="samp">gray</samp>’</dt> |
| <dd><p>Only decode/encode grayscale. |
| </p></dd> |
| <dt>‘<samp class="samp">psnr</samp>’</dt> |
| <dd><p>Set error[?] variables during encoding. |
| </p></dd> |
| <dt>‘<samp class="samp">truncated</samp>’</dt> |
| <dd><p>Input bitstream might be randomly truncated. |
| </p></dd> |
| <dt>‘<samp class="samp">drop_changed</samp>’</dt> |
| <dd><p>Don’t output frames whose parameters differ from first decoded frame in stream. |
| Error AVERROR_INPUT_CHANGED is returned when a frame is dropped. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">ildct</samp>’</dt> |
| <dd><p>Use interlaced DCT. |
| </p></dd> |
| <dt>‘<samp class="samp">low_delay</samp>’</dt> |
| <dd><p>Force low delay. |
| </p></dd> |
| <dt>‘<samp class="samp">global_header</samp>’</dt> |
| <dd><p>Place global headers in extradata instead of every keyframe. |
| </p></dd> |
| <dt>‘<samp class="samp">bitexact</samp>’</dt> |
| <dd><p>Only write platform-, build- and time-independent data. (except (I)DCT). |
| This ensures that file and data checksums are reproducible and match between |
| platforms. Its primary use is for regression testing. |
| </p></dd> |
| <dt>‘<samp class="samp">aic</samp>’</dt> |
| <dd><p>Apply H263 advanced intra coding / mpeg4 ac prediction. |
| </p></dd> |
| <dt>‘<samp class="samp">ilme</samp>’</dt> |
| <dd><p>Apply interlaced motion estimation. |
| </p></dd> |
| <dt>‘<samp class="samp">cgop</samp>’</dt> |
| <dd><p>Use closed gop. |
| </p></dd> |
| <dt>‘<samp class="samp">output_corrupt</samp>’</dt> |
| <dd><p>Output even potentially corrupted frames. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">time_base <var class="var">rational number</var></samp></dt> |
| <dd><p>Set codec time base. |
| </p> |
| <p>It is the fundamental unit of time (in seconds) in terms of which |
| frame timestamps are represented. For fixed-fps content, timebase |
| should be <code class="code">1 / frame_rate</code> and timestamp increments should be |
| identically 1. |
| </p> |
| </dd> |
| <dt><samp class="option">g <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set the group of picture (GOP) size. Default value is 12. |
| </p> |
| </dd> |
| <dt><samp class="option">ar <var class="var">integer</var> (<em class="emph">decoding/encoding,audio</em>)</samp></dt> |
| <dd><p>Set audio sampling rate (in Hz). |
| </p> |
| </dd> |
| <dt><samp class="option">ac <var class="var">integer</var> (<em class="emph">decoding/encoding,audio</em>)</samp></dt> |
| <dd><p>Set number of audio channels. |
| </p> |
| </dd> |
| <dt><samp class="option">cutoff <var class="var">integer</var> (<em class="emph">encoding,audio</em>)</samp></dt> |
| <dd><p>Set cutoff bandwidth. (Supported only by selected encoders, see |
| their respective documentation sections.) |
| </p> |
| </dd> |
| <dt><samp class="option">frame_size <var class="var">integer</var> (<em class="emph">encoding,audio</em>)</samp></dt> |
| <dd><p>Set audio frame size. |
| </p> |
| <p>Each submitted frame except the last must contain exactly frame_size |
| samples per channel. May be 0 when the codec has |
| CODEC_CAP_VARIABLE_FRAME_SIZE set, in that case the frame size is not |
| restricted. It is set by some decoders to indicate constant frame |
| size. |
| </p> |
| </dd> |
| <dt><samp class="option">frame_number <var class="var">integer</var></samp></dt> |
| <dd><p>Set the frame number. |
| </p> |
| </dd> |
| <dt><samp class="option">delay <var class="var">integer</var></samp></dt> |
| <dt><samp class="option">qcomp <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set video quantizer scale compression (VBR). It is used as a constant |
| in the ratecontrol equation. Recommended range for default rc_eq: |
| 0.0-1.0. |
| </p> |
| </dd> |
| <dt><samp class="option">qblur <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set video quantizer scale blur (VBR). |
| </p> |
| </dd> |
| <dt><samp class="option">qmin <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set min video quantizer scale (VBR). Must be included between -1 and |
| 69, default value is 2. |
| </p> |
| </dd> |
| <dt><samp class="option">qmax <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set max video quantizer scale (VBR). Must be included between -1 and |
| 1024, default value is 31. |
| </p> |
| </dd> |
| <dt><samp class="option">qdiff <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set max difference between the quantizer scale (VBR). |
| </p> |
| </dd> |
| <dt><samp class="option">bf <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set max number of B frames between non-B-frames. |
| </p> |
| <p>Must be an integer between -1 and 16. 0 means that B-frames are |
| disabled. If a value of -1 is used, it will choose an automatic value |
| depending on the encoder. |
| </p> |
| <p>Default value is 0. |
| </p> |
| </dd> |
| <dt><samp class="option">b_qfactor <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set qp factor between P and B frames. |
| </p> |
| </dd> |
| <dt><samp class="option">codec_tag <var class="var">integer</var></samp></dt> |
| <dt><samp class="option">bug <var class="var">flags</var> (<em class="emph">decoding,video</em>)</samp></dt> |
| <dd><p>Workaround not auto detected encoder bugs. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">autodetect</samp>’</dt> |
| <dt>‘<samp class="samp">xvid_ilace</samp>’</dt> |
| <dd><p>Xvid interlacing bug (autodetected if fourcc==XVIX) |
| </p></dd> |
| <dt>‘<samp class="samp">ump4</samp>’</dt> |
| <dd><p>(autodetected if fourcc==UMP4) |
| </p></dd> |
| <dt>‘<samp class="samp">no_padding</samp>’</dt> |
| <dd><p>padding bug (autodetected) |
| </p></dd> |
| <dt>‘<samp class="samp">amv</samp>’</dt> |
| <dt>‘<samp class="samp">qpel_chroma</samp>’</dt> |
| <dt>‘<samp class="samp">std_qpel</samp>’</dt> |
| <dd><p>old standard qpel (autodetected per fourcc/version) |
| </p></dd> |
| <dt>‘<samp class="samp">qpel_chroma2</samp>’</dt> |
| <dt>‘<samp class="samp">direct_blocksize</samp>’</dt> |
| <dd><p>direct-qpel-blocksize bug (autodetected per fourcc/version) |
| </p></dd> |
| <dt>‘<samp class="samp">edge</samp>’</dt> |
| <dd><p>edge padding bug (autodetected per fourcc/version) |
| </p></dd> |
| <dt>‘<samp class="samp">hpel_chroma</samp>’</dt> |
| <dt>‘<samp class="samp">dc_clip</samp>’</dt> |
| <dt>‘<samp class="samp">ms</samp>’</dt> |
| <dd><p>Workaround various bugs in microsoft broken decoders. |
| </p></dd> |
| <dt>‘<samp class="samp">trunc</samp>’</dt> |
| <dd><p>trancated frames |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">strict <var class="var">integer</var> (<em class="emph">decoding/encoding,audio,video</em>)</samp></dt> |
| <dd><p>Specify how strictly to follow the standards. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">very</samp>’</dt> |
| <dd><p>strictly conform to an older more strict version of the spec or reference software |
| </p></dd> |
| <dt>‘<samp class="samp">strict</samp>’</dt> |
| <dd><p>strictly conform to all the things in the spec no matter what consequences |
| </p></dd> |
| <dt>‘<samp class="samp">normal</samp>’</dt> |
| <dt>‘<samp class="samp">unofficial</samp>’</dt> |
| <dd><p>allow unofficial extensions |
| </p></dd> |
| <dt>‘<samp class="samp">experimental</samp>’</dt> |
| <dd><p>allow non standardized experimental things, experimental |
| (unfinished/work in progress/not well tested) decoders and encoders. |
| Note: experimental decoders can pose a security risk, do not use this for |
| decoding untrusted input. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">b_qoffset <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set QP offset between P and B frames. |
| </p> |
| </dd> |
| <dt><samp class="option">err_detect <var class="var">flags</var> (<em class="emph">decoding,audio,video</em>)</samp></dt> |
| <dd><p>Set error detection flags. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">crccheck</samp>’</dt> |
| <dd><p>verify embedded CRCs |
| </p></dd> |
| <dt>‘<samp class="samp">bitstream</samp>’</dt> |
| <dd><p>detect bitstream specification deviations |
| </p></dd> |
| <dt>‘<samp class="samp">buffer</samp>’</dt> |
| <dd><p>detect improper bitstream length |
| </p></dd> |
| <dt>‘<samp class="samp">explode</samp>’</dt> |
| <dd><p>abort decoding on minor error detection |
| </p></dd> |
| <dt>‘<samp class="samp">ignore_err</samp>’</dt> |
| <dd><p>ignore decoding errors, and continue decoding. |
| This is useful if you want to analyze the content of a video and thus want |
| everything to be decoded no matter what. This option will not result in a video |
| that is pleasing to watch in case of errors. |
| </p></dd> |
| <dt>‘<samp class="samp">careful</samp>’</dt> |
| <dd><p>consider things that violate the spec and have not been seen in the wild as errors |
| </p></dd> |
| <dt>‘<samp class="samp">compliant</samp>’</dt> |
| <dd><p>consider all spec non compliancies as errors |
| </p></dd> |
| <dt>‘<samp class="samp">aggressive</samp>’</dt> |
| <dd><p>consider things that a sane encoder should not do as an error |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">has_b_frames <var class="var">integer</var></samp></dt> |
| <dt><samp class="option">block_align <var class="var">integer</var></samp></dt> |
| <dt><samp class="option">rc_override_count <var class="var">integer</var></samp></dt> |
| <dt><samp class="option">maxrate <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt> |
| <dd><p>Set max bitrate tolerance (in bits/s). Requires bufsize to be set. |
| </p> |
| </dd> |
| <dt><samp class="option">minrate <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt> |
| <dd><p>Set min bitrate tolerance (in bits/s). Most useful in setting up a CBR |
| encode. It is of little use elsewise. |
| </p> |
| </dd> |
| <dt><samp class="option">bufsize <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt> |
| <dd><p>Set ratecontrol buffer size (in bits). |
| </p> |
| </dd> |
| <dt><samp class="option">i_qfactor <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set QP factor between P and I frames. |
| </p> |
| </dd> |
| <dt><samp class="option">i_qoffset <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set QP offset between P and I frames. |
| </p> |
| </dd> |
| <dt><samp class="option">dct <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set DCT algorithm. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">auto</samp>’</dt> |
| <dd><p>autoselect a good one (default) |
| </p></dd> |
| <dt>‘<samp class="samp">fastint</samp>’</dt> |
| <dd><p>fast integer |
| </p></dd> |
| <dt>‘<samp class="samp">int</samp>’</dt> |
| <dd><p>accurate integer |
| </p></dd> |
| <dt>‘<samp class="samp">mmx</samp>’</dt> |
| <dt>‘<samp class="samp">altivec</samp>’</dt> |
| <dt>‘<samp class="samp">faan</samp>’</dt> |
| <dd><p>floating point AAN DCT |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">lumi_mask <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Compress bright areas stronger than medium ones. |
| </p> |
| </dd> |
| <dt><samp class="option">tcplx_mask <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set temporal complexity masking. |
| </p> |
| </dd> |
| <dt><samp class="option">scplx_mask <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set spatial complexity masking. |
| </p> |
| </dd> |
| <dt><samp class="option">p_mask <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set inter masking. |
| </p> |
| </dd> |
| <dt><samp class="option">dark_mask <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Compress dark areas stronger than medium ones. |
| </p> |
| </dd> |
| <dt><samp class="option">idct <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt> |
| <dd><p>Select IDCT implementation. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">auto</samp>’</dt> |
| <dt>‘<samp class="samp">int</samp>’</dt> |
| <dt>‘<samp class="samp">simple</samp>’</dt> |
| <dt>‘<samp class="samp">simplemmx</samp>’</dt> |
| <dt>‘<samp class="samp">simpleauto</samp>’</dt> |
| <dd><p>Automatically pick a IDCT compatible with the simple one |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">arm</samp>’</dt> |
| <dt>‘<samp class="samp">altivec</samp>’</dt> |
| <dt>‘<samp class="samp">sh4</samp>’</dt> |
| <dt>‘<samp class="samp">simplearm</samp>’</dt> |
| <dt>‘<samp class="samp">simplearmv5te</samp>’</dt> |
| <dt>‘<samp class="samp">simplearmv6</samp>’</dt> |
| <dt>‘<samp class="samp">simpleneon</samp>’</dt> |
| <dt>‘<samp class="samp">xvid</samp>’</dt> |
| <dt>‘<samp class="samp">faani</samp>’</dt> |
| <dd><p>floating point AAN IDCT |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">slice_count <var class="var">integer</var></samp></dt> |
| <dt><samp class="option">ec <var class="var">flags</var> (<em class="emph">decoding,video</em>)</samp></dt> |
| <dd><p>Set error concealment strategy. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">guess_mvs</samp>’</dt> |
| <dd><p>iterative motion vector (MV) search (slow) |
| </p></dd> |
| <dt>‘<samp class="samp">deblock</samp>’</dt> |
| <dd><p>use strong deblock filter for damaged MBs |
| </p></dd> |
| <dt>‘<samp class="samp">favor_inter</samp>’</dt> |
| <dd><p>favor predicting from the previous frame instead of the current |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">bits_per_coded_sample <var class="var">integer</var></samp></dt> |
| <dt><samp class="option">aspect <var class="var">rational number</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set sample aspect ratio. |
| </p> |
| </dd> |
| <dt><samp class="option">sar <var class="var">rational number</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set sample aspect ratio. Alias to <var class="var">aspect</var>. |
| </p> |
| </dd> |
| <dt><samp class="option">debug <var class="var">flags</var> (<em class="emph">decoding/encoding,audio,video,subtitles</em>)</samp></dt> |
| <dd><p>Print specific debug info. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">pict</samp>’</dt> |
| <dd><p>picture info |
| </p></dd> |
| <dt>‘<samp class="samp">rc</samp>’</dt> |
| <dd><p>rate control |
| </p></dd> |
| <dt>‘<samp class="samp">bitstream</samp>’</dt> |
| <dt>‘<samp class="samp">mb_type</samp>’</dt> |
| <dd><p>macroblock (MB) type |
| </p></dd> |
| <dt>‘<samp class="samp">qp</samp>’</dt> |
| <dd><p>per-block quantization parameter (QP) |
| </p></dd> |
| <dt>‘<samp class="samp">dct_coeff</samp>’</dt> |
| <dt>‘<samp class="samp">green_metadata</samp>’</dt> |
| <dd><p>display complexity metadata for the upcoming frame, GoP or for a given duration. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">skip</samp>’</dt> |
| <dt>‘<samp class="samp">startcode</samp>’</dt> |
| <dt>‘<samp class="samp">er</samp>’</dt> |
| <dd><p>error recognition |
| </p></dd> |
| <dt>‘<samp class="samp">mmco</samp>’</dt> |
| <dd><p>memory management control operations (H.264) |
| </p></dd> |
| <dt>‘<samp class="samp">bugs</samp>’</dt> |
| <dt>‘<samp class="samp">buffers</samp>’</dt> |
| <dd><p>picture buffer allocations |
| </p></dd> |
| <dt>‘<samp class="samp">thread_ops</samp>’</dt> |
| <dd><p>threading operations |
| </p></dd> |
| <dt>‘<samp class="samp">nomc</samp>’</dt> |
| <dd><p>skip motion compensation |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">cmp <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set full pel me compare function. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">sad</samp>’</dt> |
| <dd><p>sum of absolute differences, fast (default) |
| </p></dd> |
| <dt>‘<samp class="samp">sse</samp>’</dt> |
| <dd><p>sum of squared errors |
| </p></dd> |
| <dt>‘<samp class="samp">satd</samp>’</dt> |
| <dd><p>sum of absolute Hadamard transformed differences |
| </p></dd> |
| <dt>‘<samp class="samp">dct</samp>’</dt> |
| <dd><p>sum of absolute DCT transformed differences |
| </p></dd> |
| <dt>‘<samp class="samp">psnr</samp>’</dt> |
| <dd><p>sum of squared quantization errors (avoid, low quality) |
| </p></dd> |
| <dt>‘<samp class="samp">bit</samp>’</dt> |
| <dd><p>number of bits needed for the block |
| </p></dd> |
| <dt>‘<samp class="samp">rd</samp>’</dt> |
| <dd><p>rate distortion optimal, slow |
| </p></dd> |
| <dt>‘<samp class="samp">zero</samp>’</dt> |
| <dd><p>0 |
| </p></dd> |
| <dt>‘<samp class="samp">vsad</samp>’</dt> |
| <dd><p>sum of absolute vertical differences |
| </p></dd> |
| <dt>‘<samp class="samp">vsse</samp>’</dt> |
| <dd><p>sum of squared vertical differences |
| </p></dd> |
| <dt>‘<samp class="samp">nsse</samp>’</dt> |
| <dd><p>noise preserving sum of squared differences |
| </p></dd> |
| <dt>‘<samp class="samp">w53</samp>’</dt> |
| <dd><p>5/3 wavelet, only used in snow |
| </p></dd> |
| <dt>‘<samp class="samp">w97</samp>’</dt> |
| <dd><p>9/7 wavelet, only used in snow |
| </p></dd> |
| <dt>‘<samp class="samp">dctmax</samp>’</dt> |
| <dt>‘<samp class="samp">chroma</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">subcmp <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set sub pel me compare function. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">sad</samp>’</dt> |
| <dd><p>sum of absolute differences, fast (default) |
| </p></dd> |
| <dt>‘<samp class="samp">sse</samp>’</dt> |
| <dd><p>sum of squared errors |
| </p></dd> |
| <dt>‘<samp class="samp">satd</samp>’</dt> |
| <dd><p>sum of absolute Hadamard transformed differences |
| </p></dd> |
| <dt>‘<samp class="samp">dct</samp>’</dt> |
| <dd><p>sum of absolute DCT transformed differences |
| </p></dd> |
| <dt>‘<samp class="samp">psnr</samp>’</dt> |
| <dd><p>sum of squared quantization errors (avoid, low quality) |
| </p></dd> |
| <dt>‘<samp class="samp">bit</samp>’</dt> |
| <dd><p>number of bits needed for the block |
| </p></dd> |
| <dt>‘<samp class="samp">rd</samp>’</dt> |
| <dd><p>rate distortion optimal, slow |
| </p></dd> |
| <dt>‘<samp class="samp">zero</samp>’</dt> |
| <dd><p>0 |
| </p></dd> |
| <dt>‘<samp class="samp">vsad</samp>’</dt> |
| <dd><p>sum of absolute vertical differences |
| </p></dd> |
| <dt>‘<samp class="samp">vsse</samp>’</dt> |
| <dd><p>sum of squared vertical differences |
| </p></dd> |
| <dt>‘<samp class="samp">nsse</samp>’</dt> |
| <dd><p>noise preserving sum of squared differences |
| </p></dd> |
| <dt>‘<samp class="samp">w53</samp>’</dt> |
| <dd><p>5/3 wavelet, only used in snow |
| </p></dd> |
| <dt>‘<samp class="samp">w97</samp>’</dt> |
| <dd><p>9/7 wavelet, only used in snow |
| </p></dd> |
| <dt>‘<samp class="samp">dctmax</samp>’</dt> |
| <dt>‘<samp class="samp">chroma</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">mbcmp <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set macroblock compare function. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">sad</samp>’</dt> |
| <dd><p>sum of absolute differences, fast (default) |
| </p></dd> |
| <dt>‘<samp class="samp">sse</samp>’</dt> |
| <dd><p>sum of squared errors |
| </p></dd> |
| <dt>‘<samp class="samp">satd</samp>’</dt> |
| <dd><p>sum of absolute Hadamard transformed differences |
| </p></dd> |
| <dt>‘<samp class="samp">dct</samp>’</dt> |
| <dd><p>sum of absolute DCT transformed differences |
| </p></dd> |
| <dt>‘<samp class="samp">psnr</samp>’</dt> |
| <dd><p>sum of squared quantization errors (avoid, low quality) |
| </p></dd> |
| <dt>‘<samp class="samp">bit</samp>’</dt> |
| <dd><p>number of bits needed for the block |
| </p></dd> |
| <dt>‘<samp class="samp">rd</samp>’</dt> |
| <dd><p>rate distortion optimal, slow |
| </p></dd> |
| <dt>‘<samp class="samp">zero</samp>’</dt> |
| <dd><p>0 |
| </p></dd> |
| <dt>‘<samp class="samp">vsad</samp>’</dt> |
| <dd><p>sum of absolute vertical differences |
| </p></dd> |
| <dt>‘<samp class="samp">vsse</samp>’</dt> |
| <dd><p>sum of squared vertical differences |
| </p></dd> |
| <dt>‘<samp class="samp">nsse</samp>’</dt> |
| <dd><p>noise preserving sum of squared differences |
| </p></dd> |
| <dt>‘<samp class="samp">w53</samp>’</dt> |
| <dd><p>5/3 wavelet, only used in snow |
| </p></dd> |
| <dt>‘<samp class="samp">w97</samp>’</dt> |
| <dd><p>9/7 wavelet, only used in snow |
| </p></dd> |
| <dt>‘<samp class="samp">dctmax</samp>’</dt> |
| <dt>‘<samp class="samp">chroma</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">ildctcmp <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set interlaced dct compare function. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">sad</samp>’</dt> |
| <dd><p>sum of absolute differences, fast (default) |
| </p></dd> |
| <dt>‘<samp class="samp">sse</samp>’</dt> |
| <dd><p>sum of squared errors |
| </p></dd> |
| <dt>‘<samp class="samp">satd</samp>’</dt> |
| <dd><p>sum of absolute Hadamard transformed differences |
| </p></dd> |
| <dt>‘<samp class="samp">dct</samp>’</dt> |
| <dd><p>sum of absolute DCT transformed differences |
| </p></dd> |
| <dt>‘<samp class="samp">psnr</samp>’</dt> |
| <dd><p>sum of squared quantization errors (avoid, low quality) |
| </p></dd> |
| <dt>‘<samp class="samp">bit</samp>’</dt> |
| <dd><p>number of bits needed for the block |
| </p></dd> |
| <dt>‘<samp class="samp">rd</samp>’</dt> |
| <dd><p>rate distortion optimal, slow |
| </p></dd> |
| <dt>‘<samp class="samp">zero</samp>’</dt> |
| <dd><p>0 |
| </p></dd> |
| <dt>‘<samp class="samp">vsad</samp>’</dt> |
| <dd><p>sum of absolute vertical differences |
| </p></dd> |
| <dt>‘<samp class="samp">vsse</samp>’</dt> |
| <dd><p>sum of squared vertical differences |
| </p></dd> |
| <dt>‘<samp class="samp">nsse</samp>’</dt> |
| <dd><p>noise preserving sum of squared differences |
| </p></dd> |
| <dt>‘<samp class="samp">w53</samp>’</dt> |
| <dd><p>5/3 wavelet, only used in snow |
| </p></dd> |
| <dt>‘<samp class="samp">w97</samp>’</dt> |
| <dd><p>9/7 wavelet, only used in snow |
| </p></dd> |
| <dt>‘<samp class="samp">dctmax</samp>’</dt> |
| <dt>‘<samp class="samp">chroma</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">dia_size <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set diamond type & size for motion estimation. |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">(1024, INT_MAX)</samp>’</dt> |
| <dd><p>full motion estimation(slowest) |
| </p></dd> |
| <dt>‘<samp class="samp">(768, 1024]</samp>’</dt> |
| <dd><p>umh motion estimation |
| </p></dd> |
| <dt>‘<samp class="samp">(512, 768]</samp>’</dt> |
| <dd><p>hex motion estimation |
| </p></dd> |
| <dt>‘<samp class="samp">(256, 512]</samp>’</dt> |
| <dd><p>l2s diamond motion estimation |
| </p></dd> |
| <dt>‘<samp class="samp">[2,256]</samp>’</dt> |
| <dd><p>var diamond motion estimation |
| </p></dd> |
| <dt>‘<samp class="samp">(-1, 2)</samp>’</dt> |
| <dd><p>small diamond motion estimation |
| </p></dd> |
| <dt>‘<samp class="samp">-1</samp>’</dt> |
| <dd><p>funny diamond motion estimation |
| </p></dd> |
| <dt>‘<samp class="samp">(INT_MIN, -1)</samp>’</dt> |
| <dd><p>sab diamond motion estimation |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">last_pred <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set amount of motion predictors from the previous frame. |
| </p> |
| </dd> |
| <dt><samp class="option">precmp <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set pre motion estimation compare function. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">sad</samp>’</dt> |
| <dd><p>sum of absolute differences, fast (default) |
| </p></dd> |
| <dt>‘<samp class="samp">sse</samp>’</dt> |
| <dd><p>sum of squared errors |
| </p></dd> |
| <dt>‘<samp class="samp">satd</samp>’</dt> |
| <dd><p>sum of absolute Hadamard transformed differences |
| </p></dd> |
| <dt>‘<samp class="samp">dct</samp>’</dt> |
| <dd><p>sum of absolute DCT transformed differences |
| </p></dd> |
| <dt>‘<samp class="samp">psnr</samp>’</dt> |
| <dd><p>sum of squared quantization errors (avoid, low quality) |
| </p></dd> |
| <dt>‘<samp class="samp">bit</samp>’</dt> |
| <dd><p>number of bits needed for the block |
| </p></dd> |
| <dt>‘<samp class="samp">rd</samp>’</dt> |
| <dd><p>rate distortion optimal, slow |
| </p></dd> |
| <dt>‘<samp class="samp">zero</samp>’</dt> |
| <dd><p>0 |
| </p></dd> |
| <dt>‘<samp class="samp">vsad</samp>’</dt> |
| <dd><p>sum of absolute vertical differences |
| </p></dd> |
| <dt>‘<samp class="samp">vsse</samp>’</dt> |
| <dd><p>sum of squared vertical differences |
| </p></dd> |
| <dt>‘<samp class="samp">nsse</samp>’</dt> |
| <dd><p>noise preserving sum of squared differences |
| </p></dd> |
| <dt>‘<samp class="samp">w53</samp>’</dt> |
| <dd><p>5/3 wavelet, only used in snow |
| </p></dd> |
| <dt>‘<samp class="samp">w97</samp>’</dt> |
| <dd><p>9/7 wavelet, only used in snow |
| </p></dd> |
| <dt>‘<samp class="samp">dctmax</samp>’</dt> |
| <dt>‘<samp class="samp">chroma</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">pre_dia_size <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set diamond type & size for motion estimation pre-pass. |
| </p> |
| </dd> |
| <dt><samp class="option">subq <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set sub pel motion estimation quality. |
| </p> |
| </dd> |
| <dt><samp class="option">me_range <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set limit motion vectors range (1023 for DivX player). |
| </p> |
| </dd> |
| <dt><samp class="option">global_quality <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt> |
| <dt><samp class="option">slice_flags <var class="var">integer</var></samp></dt> |
| <dt><samp class="option">mbd <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set macroblock decision algorithm (high quality mode). |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">simple</samp>’</dt> |
| <dd><p>use mbcmp (default) |
| </p></dd> |
| <dt>‘<samp class="samp">bits</samp>’</dt> |
| <dd><p>use fewest bits |
| </p></dd> |
| <dt>‘<samp class="samp">rd</samp>’</dt> |
| <dd><p>use best rate distortion |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">rc_init_occupancy <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set number of bits which should be loaded into the rc buffer before |
| decoding starts. |
| </p> |
| </dd> |
| <dt><samp class="option">flags2 <var class="var">flags</var> (<em class="emph">decoding/encoding,audio,video,subtitles</em>)</samp></dt> |
| <dd> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">fast</samp>’</dt> |
| <dd><p>Allow non spec compliant speedup tricks. |
| </p></dd> |
| <dt>‘<samp class="samp">noout</samp>’</dt> |
| <dd><p>Skip bitstream encoding. |
| </p></dd> |
| <dt>‘<samp class="samp">ignorecrop</samp>’</dt> |
| <dd><p>Ignore cropping information from sps. |
| </p></dd> |
| <dt>‘<samp class="samp">local_header</samp>’</dt> |
| <dd><p>Place global headers at every keyframe instead of in extradata. |
| </p></dd> |
| <dt>‘<samp class="samp">chunks</samp>’</dt> |
| <dd><p>Frame data might be split into multiple chunks. |
| </p></dd> |
| <dt>‘<samp class="samp">showall</samp>’</dt> |
| <dd><p>Show all frames before the first keyframe. |
| </p></dd> |
| <dt>‘<samp class="samp">export_mvs</samp>’</dt> |
| <dd><p>Export motion vectors into frame side-data (see <code class="code">AV_FRAME_DATA_MOTION_VECTORS</code>) |
| for codecs that support it. See also <samp class="file">doc/examples/export_mvs.c</samp>. |
| </p></dd> |
| <dt>‘<samp class="samp">skip_manual</samp>’</dt> |
| <dd><p>Do not skip samples and export skip information as frame side data. |
| </p></dd> |
| <dt>‘<samp class="samp">ass_ro_flush_noop</samp>’</dt> |
| <dd><p>Do not reset ASS ReadOrder field on flush. |
| </p></dd> |
| <dt>‘<samp class="samp">icc_profiles</samp>’</dt> |
| <dd><p>Generate/parse embedded ICC profiles from/to colorimetry tags. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">export_side_data <var class="var">flags</var> (<em class="emph">decoding/encoding,audio,video,subtitles</em>)</samp></dt> |
| <dd> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">mvs</samp>’</dt> |
| <dd><p>Export motion vectors into frame side-data (see <code class="code">AV_FRAME_DATA_MOTION_VECTORS</code>) |
| for codecs that support it. See also <samp class="file">doc/examples/export_mvs.c</samp>. |
| </p></dd> |
| <dt>‘<samp class="samp">prft</samp>’</dt> |
| <dd><p>Export encoder Producer Reference Time into packet side-data (see <code class="code">AV_PKT_DATA_PRFT</code>) |
| for codecs that support it. |
| </p></dd> |
| <dt>‘<samp class="samp">venc_params</samp>’</dt> |
| <dd><p>Export video encoding parameters through frame side data (see <code class="code">AV_FRAME_DATA_VIDEO_ENC_PARAMS</code>) |
| for codecs that support it. At present, those are H.264 and VP9. |
| </p></dd> |
| <dt>‘<samp class="samp">film_grain</samp>’</dt> |
| <dd><p>Export film grain parameters through frame side data (see <code class="code">AV_FRAME_DATA_FILM_GRAIN_PARAMS</code>). |
| Supported at present by AV1 decoders. |
| </p></dd> |
| <dt>‘<samp class="samp">enhancements</samp>’</dt> |
| <dd><p>Export picture enhancement metadata through frame side data, e.g. LCEVC (see <code class="code">AV_FRAME_DATA_LCEVC</code>). |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">threads <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt> |
| <dd><p>Set the number of threads to be used, in case the selected codec |
| implementation supports multi-threading. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">auto, 0</samp>’</dt> |
| <dd><p>automatically select the number of threads to set |
| </p></dd> |
| </dl> |
|
|
| <p>Default value is ‘<samp class="samp">auto</samp>’. |
| </p> |
| </dd> |
| <dt><samp class="option">dc <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set intra_dc_precision. |
| </p> |
| </dd> |
| <dt><samp class="option">nssew <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set nsse weight. |
| </p> |
| </dd> |
| <dt><samp class="option">skip_top <var class="var">integer</var> (<em class="emph">decoding,video</em>)</samp></dt> |
| <dd><p>Set number of macroblock rows at the top which are skipped. |
| </p> |
| </dd> |
| <dt><samp class="option">skip_bottom <var class="var">integer</var> (<em class="emph">decoding,video</em>)</samp></dt> |
| <dd><p>Set number of macroblock rows at the bottom which are skipped. |
| </p> |
| </dd> |
| <dt><samp class="option">profile <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt> |
| <dd> |
| <p>Set encoder codec profile. Default value is ‘<samp class="samp">unknown</samp>’. Encoder specific |
| profiles are documented in the relevant encoder documentation. |
| </p> |
| </dd> |
| <dt><samp class="option">level <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt> |
| <dd> |
| <p>Set the encoder level. This level depends on the specific codec, and |
| might correspond to the profile level. It is set by default to |
| ‘<samp class="samp">unknown</samp>’. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">unknown</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">lowres <var class="var">integer</var> (<em class="emph">decoding,audio,video</em>)</samp></dt> |
| <dd><p>Decode at 1= 1/2, 2=1/4, 3=1/8 resolutions. |
| </p> |
| </dd> |
| <dt><samp class="option">mblmin <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set min macroblock lagrange factor (VBR). |
| </p> |
| </dd> |
| <dt><samp class="option">mblmax <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set max macroblock lagrange factor (VBR). |
| </p> |
| </dd> |
| <dt><samp class="option">skip_loop_filter <var class="var">integer</var> (<em class="emph">decoding,video</em>)</samp></dt> |
| <dt><samp class="option">skip_idct <var class="var">integer</var> (<em class="emph">decoding,video</em>)</samp></dt> |
| <dt><samp class="option">skip_frame <var class="var">integer</var> (<em class="emph">decoding,video</em>)</samp></dt> |
| <dd> |
| <p>Make decoder discard processing depending on the frame type selected |
| by the option value. |
| </p> |
| <p><samp class="option">skip_loop_filter</samp> skips frame loop filtering, <samp class="option">skip_idct</samp> |
| skips frame IDCT/dequantization, <samp class="option">skip_frame</samp> skips decoding. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">none</samp>’</dt> |
| <dd><p>Discard no frame. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">default</samp>’</dt> |
| <dd><p>Discard useless frames like 0-sized frames. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">noref</samp>’</dt> |
| <dd><p>Discard all non-reference frames. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">bidir</samp>’</dt> |
| <dd><p>Discard all bidirectional frames. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">nokey</samp>’</dt> |
| <dd><p>Discard all frames excepts keyframes. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">nointra</samp>’</dt> |
| <dd><p>Discard all frames except I frames. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">all</samp>’</dt> |
| <dd><p>Discard all frames. |
| </p></dd> |
| </dl> |
|
|
| <p>Default value is ‘<samp class="samp">default</samp>’. |
| </p> |
| </dd> |
| <dt><samp class="option">bidir_refine <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Refine the two motion vectors used in bidirectional macroblocks. |
| </p> |
| </dd> |
| <dt><samp class="option">keyint_min <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set minimum interval between IDR-frames. |
| </p> |
| </dd> |
| <dt><samp class="option">refs <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Set reference frames to consider for motion compensation. |
| </p> |
| </dd> |
| <dt><samp class="option">trellis <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt> |
| <dd><p>Set rate-distortion optimal quantization. |
| </p> |
| </dd> |
| <dt><samp class="option">mv0_threshold <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dt><samp class="option">compression_level <var class="var">integer</var> (<em class="emph">encoding,audio,video</em>)</samp></dt> |
| <dt><samp class="option">bits_per_raw_sample <var class="var">integer</var></samp></dt> |
| <dt><samp class="option">channel_layout <var class="var">integer</var> (<em class="emph">decoding/encoding,audio</em>)</samp></dt> |
| <dd><p>See <a data-manual="ffmpeg-utils" href="ffmpeg-utils.html#channel-layout-syntax">the Channel Layout section in the ffmpeg-utils(1) manual</a> |
| for the required syntax. |
| </p> |
| </dd> |
| <dt><samp class="option">rc_max_vbv_use <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dt><samp class="option">rc_min_vbv_use <var class="var">float</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dt><samp class="option">color_primaries <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt> |
| <dd><p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">bt709</samp>’</dt> |
| <dd><p>BT.709 |
| </p></dd> |
| <dt>‘<samp class="samp">bt470m</samp>’</dt> |
| <dd><p>BT.470 M |
| </p></dd> |
| <dt>‘<samp class="samp">bt470bg</samp>’</dt> |
| <dd><p>BT.470 BG |
| </p></dd> |
| <dt>‘<samp class="samp">smpte170m</samp>’</dt> |
| <dd><p>SMPTE 170 M |
| </p></dd> |
| <dt>‘<samp class="samp">smpte240m</samp>’</dt> |
| <dd><p>SMPTE 240 M |
| </p></dd> |
| <dt>‘<samp class="samp">film</samp>’</dt> |
| <dd><p>Film |
| </p></dd> |
| <dt>‘<samp class="samp">bt2020</samp>’</dt> |
| <dd><p>BT.2020 |
| </p></dd> |
| <dt>‘<samp class="samp">smpte428</samp>’</dt> |
| <dt>‘<samp class="samp">smpte428_1</samp>’</dt> |
| <dd><p>SMPTE ST 428-1 |
| </p></dd> |
| <dt>‘<samp class="samp">smpte431</samp>’</dt> |
| <dd><p>SMPTE 431-2 |
| </p></dd> |
| <dt>‘<samp class="samp">smpte432</samp>’</dt> |
| <dd><p>SMPTE 432-1 |
| </p></dd> |
| <dt>‘<samp class="samp">jedec-p22</samp>’</dt> |
| <dd><p>JEDEC P22 |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">color_trc <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt> |
| <dd><p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">bt709</samp>’</dt> |
| <dd><p>BT.709 |
| </p></dd> |
| <dt>‘<samp class="samp">gamma22</samp>’</dt> |
| <dd><p>BT.470 M |
| </p></dd> |
| <dt>‘<samp class="samp">gamma28</samp>’</dt> |
| <dd><p>BT.470 BG |
| </p></dd> |
| <dt>‘<samp class="samp">smpte170m</samp>’</dt> |
| <dd><p>SMPTE 170 M |
| </p></dd> |
| <dt>‘<samp class="samp">smpte240m</samp>’</dt> |
| <dd><p>SMPTE 240 M |
| </p></dd> |
| <dt>‘<samp class="samp">linear</samp>’</dt> |
| <dd><p>Linear |
| </p></dd> |
| <dt>‘<samp class="samp">log</samp>’</dt> |
| <dt>‘<samp class="samp">log100</samp>’</dt> |
| <dd><p>Log |
| </p></dd> |
| <dt>‘<samp class="samp">log_sqrt</samp>’</dt> |
| <dt>‘<samp class="samp">log316</samp>’</dt> |
| <dd><p>Log square root |
| </p></dd> |
| <dt>‘<samp class="samp">iec61966_2_4</samp>’</dt> |
| <dt>‘<samp class="samp">iec61966-2-4</samp>’</dt> |
| <dd><p>IEC 61966-2-4 |
| </p></dd> |
| <dt>‘<samp class="samp">bt1361</samp>’</dt> |
| <dt>‘<samp class="samp">bt1361e</samp>’</dt> |
| <dd><p>BT.1361 |
| </p></dd> |
| <dt>‘<samp class="samp">iec61966_2_1</samp>’</dt> |
| <dt>‘<samp class="samp">iec61966-2-1</samp>’</dt> |
| <dd><p>IEC 61966-2-1 |
| </p></dd> |
| <dt>‘<samp class="samp">bt2020_10</samp>’</dt> |
| <dt>‘<samp class="samp">bt2020_10bit</samp>’</dt> |
| <dd><p>BT.2020 - 10 bit |
| </p></dd> |
| <dt>‘<samp class="samp">bt2020_12</samp>’</dt> |
| <dt>‘<samp class="samp">bt2020_12bit</samp>’</dt> |
| <dd><p>BT.2020 - 12 bit |
| </p></dd> |
| <dt>‘<samp class="samp">smpte2084</samp>’</dt> |
| <dd><p>SMPTE ST 2084 |
| </p></dd> |
| <dt>‘<samp class="samp">smpte428</samp>’</dt> |
| <dt>‘<samp class="samp">smpte428_1</samp>’</dt> |
| <dd><p>SMPTE ST 428-1 |
| </p></dd> |
| <dt>‘<samp class="samp">arib-std-b67</samp>’</dt> |
| <dd><p>ARIB STD-B67 |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">colorspace <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt> |
| <dd><p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">rgb</samp>’</dt> |
| <dd><p>RGB |
| </p></dd> |
| <dt>‘<samp class="samp">bt709</samp>’</dt> |
| <dd><p>BT.709 |
| </p></dd> |
| <dt>‘<samp class="samp">fcc</samp>’</dt> |
| <dd><p>FCC |
| </p></dd> |
| <dt>‘<samp class="samp">bt470bg</samp>’</dt> |
| <dd><p>BT.470 BG |
| </p></dd> |
| <dt>‘<samp class="samp">smpte170m</samp>’</dt> |
| <dd><p>SMPTE 170 M |
| </p></dd> |
| <dt>‘<samp class="samp">smpte240m</samp>’</dt> |
| <dd><p>SMPTE 240 M |
| </p></dd> |
| <dt>‘<samp class="samp">ycocg</samp>’</dt> |
| <dd><p>YCOCG |
| </p></dd> |
| <dt>‘<samp class="samp">bt2020nc</samp>’</dt> |
| <dt>‘<samp class="samp">bt2020_ncl</samp>’</dt> |
| <dd><p>BT.2020 NCL |
| </p></dd> |
| <dt>‘<samp class="samp">bt2020c</samp>’</dt> |
| <dt>‘<samp class="samp">bt2020_cl</samp>’</dt> |
| <dd><p>BT.2020 CL |
| </p></dd> |
| <dt>‘<samp class="samp">smpte2085</samp>’</dt> |
| <dd><p>SMPTE 2085 |
| </p></dd> |
| <dt>‘<samp class="samp">chroma-derived-nc</samp>’</dt> |
| <dd><p>Chroma-derived NCL |
| </p></dd> |
| <dt>‘<samp class="samp">chroma-derived-c</samp>’</dt> |
| <dd><p>Chroma-derived CL |
| </p></dd> |
| <dt>‘<samp class="samp">ictcp</samp>’</dt> |
| <dd><p>ICtCp |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">color_range <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt> |
| <dd><p>If used as input parameter, it serves as a hint to the decoder, which |
| color_range the input has. |
| Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">tv</samp>’</dt> |
| <dt>‘<samp class="samp">mpeg</samp>’</dt> |
| <dt>‘<samp class="samp">limited</samp>’</dt> |
| <dd><p>MPEG (219*2^(n-8)) |
| </p></dd> |
| <dt>‘<samp class="samp">pc</samp>’</dt> |
| <dt>‘<samp class="samp">jpeg</samp>’</dt> |
| <dt>‘<samp class="samp">full</samp>’</dt> |
| <dd><p>JPEG (2^n-1) |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">chroma_sample_location <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt> |
| <dd><p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">left</samp>’</dt> |
| <dt>‘<samp class="samp">center</samp>’</dt> |
| <dt>‘<samp class="samp">topleft</samp>’</dt> |
| <dt>‘<samp class="samp">top</samp>’</dt> |
| <dt>‘<samp class="samp">bottomleft</samp>’</dt> |
| <dt>‘<samp class="samp">bottom</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">alpha_mode <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt> |
| <dd><p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">premultiplied</samp>’</dt> |
| <dt>‘<samp class="samp">straight</samp>’</dt> |
| </dl> |
|
|
|
|
| </dd> |
| <dt><samp class="option">log_level_offset <var class="var">integer</var></samp></dt> |
| <dd><p>Set the log level offset. |
| </p> |
| </dd> |
| <dt><samp class="option">slices <var class="var">integer</var> (<em class="emph">encoding,video</em>)</samp></dt> |
| <dd><p>Number of slices, used in parallelized encoding. |
| </p> |
| </dd> |
| <dt><samp class="option">thread_type <var class="var">flags</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt> |
| <dd><p>Select which multithreading methods to use. |
| </p> |
| <p>Use of ‘<samp class="samp">frame</samp>’ will increase decoding delay by one frame per |
| thread, so clients which cannot provide future frames should not use |
| it. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">slice</samp>’</dt> |
| <dd><p>Decode more than one part of a single frame at once. |
| </p> |
| <p>Multithreading using slices works only when the video was encoded with |
| slices. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">frame</samp>’</dt> |
| <dd><p>Decode more than one frame at once. |
| </p></dd> |
| </dl> |
|
|
| <p>Default value is ‘<samp class="samp">slice+frame</samp>’. |
| </p> |
| </dd> |
| <dt><samp class="option">audio_service_type <var class="var">integer</var> (<em class="emph">encoding,audio</em>)</samp></dt> |
| <dd><p>Set audio service type. |
| </p> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">ma</samp>’</dt> |
| <dd><p>Main Audio Service |
| </p></dd> |
| <dt>‘<samp class="samp">ef</samp>’</dt> |
| <dd><p>Effects |
| </p></dd> |
| <dt>‘<samp class="samp">vi</samp>’</dt> |
| <dd><p>Visually Impaired |
| </p></dd> |
| <dt>‘<samp class="samp">hi</samp>’</dt> |
| <dd><p>Hearing Impaired |
| </p></dd> |
| <dt>‘<samp class="samp">di</samp>’</dt> |
| <dd><p>Dialogue |
| </p></dd> |
| <dt>‘<samp class="samp">co</samp>’</dt> |
| <dd><p>Commentary |
| </p></dd> |
| <dt>‘<samp class="samp">em</samp>’</dt> |
| <dd><p>Emergency |
| </p></dd> |
| <dt>‘<samp class="samp">vo</samp>’</dt> |
| <dd><p>Voice Over |
| </p></dd> |
| <dt>‘<samp class="samp">ka</samp>’</dt> |
| <dd><p>Karaoke |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">request_sample_fmt <var class="var">sample_fmt</var> (<em class="emph">decoding,audio</em>)</samp></dt> |
| <dd><p>Set sample format audio decoders should prefer. Default value is |
| <code class="code">none</code>. |
| </p> |
| </dd> |
| <dt><samp class="option">pkt_timebase <var class="var">rational number</var></samp></dt> |
| <dt><samp class="option">sub_charenc <var class="var">encoding</var> (<em class="emph">decoding,subtitles</em>)</samp></dt> |
| <dd><p>Set the input subtitles character encoding. |
| </p> |
| </dd> |
| <dt><samp class="option">field_order <var class="var">field_order</var> (<em class="emph">video</em>)</samp></dt> |
| <dd><p>Set/override the field order of the video. |
| Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">progressive</samp>’</dt> |
| <dd><p>Progressive video |
| </p></dd> |
| <dt>‘<samp class="samp">tt</samp>’</dt> |
| <dd><p>Interlaced video, top field coded and displayed first |
| </p></dd> |
| <dt>‘<samp class="samp">bb</samp>’</dt> |
| <dd><p>Interlaced video, bottom field coded and displayed first |
| </p></dd> |
| <dt>‘<samp class="samp">tb</samp>’</dt> |
| <dd><p>Interlaced video, top coded first, bottom displayed first |
| </p></dd> |
| <dt>‘<samp class="samp">bt</samp>’</dt> |
| <dd><p>Interlaced video, bottom coded first, top displayed first |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">skip_alpha <var class="var">bool</var> (<em class="emph">decoding,video</em>)</samp></dt> |
| <dd><p>Set to 1 to disable processing alpha (transparency). This works like the |
| ‘<samp class="samp">gray</samp>’ flag in the <samp class="option">flags</samp> option which skips chroma information |
| instead of alpha. Default is 0. |
| </p> |
| </dd> |
| <dt><samp class="option">codec_whitelist <var class="var">list</var> (<em class="emph">input</em>)</samp></dt> |
| <dd><p>"," separated list of allowed decoders. By default all are allowed. |
| </p> |
| </dd> |
| <dt><samp class="option">dump_separator <var class="var">string</var> (<em class="emph">input</em>)</samp></dt> |
| <dd><p>Separator used to separate the fields printed on the command line about the |
| Stream parameters. |
| For example, to separate the fields with newlines and indentation: |
| </p><div class="example"> |
| <pre class="example-preformatted">ffprobe -dump_separator " |
| " -i ~/videos/matrixbench_mpeg2.mpg |
| </pre></div> |
|
|
| </dd> |
| <dt><samp class="option">max_pixels <var class="var">integer</var> (<em class="emph">decoding/encoding,video</em>)</samp></dt> |
| <dd><p>Maximum number of pixels per image. This value can be used to avoid out of |
| memory failures due to large images. |
| </p> |
| </dd> |
| <dt><samp class="option">apply_cropping <var class="var">bool</var> (<em class="emph">decoding,video</em>)</samp></dt> |
| <dd><p>Enable cropping if cropping parameters are multiples of the required |
| alignment for the left and top parameters. If the alignment is not met the |
| cropping will be partially applied to maintain alignment. |
| Default is 1 (enabled). |
| Note: The required alignment depends on if <code class="code">AV_CODEC_FLAG_UNALIGNED</code> is set and the |
| CPU. <code class="code">AV_CODEC_FLAG_UNALIGNED</code> cannot be changed from the command line. Also hardware |
| decoders will not apply left/top Cropping. |
| </p> |
|
|
| </dd> |
| </dl> |
|
|
|
|
| <a name="Decoders"></a> |
| <h2 class="chapter">3 Decoders<span class="pull-right"><a class="anchor hidden-xs" href="#Decoders" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Decoders" aria-hidden="true">TOC</a></span></h2> |
|
|
| <p>Decoders are configured elements in FFmpeg which allow the decoding of |
| multimedia streams. |
| </p> |
| <p>When you configure your FFmpeg build, all the supported native decoders |
| are enabled by default. Decoders requiring an external library must be enabled |
| manually via the corresponding <code class="code">--enable-lib</code> option. You can list all |
| available decoders using the configure option <code class="code">--list-decoders</code>. |
| </p> |
| <p>You can disable all the decoders with the configure option |
| <code class="code">--disable-decoders</code> and selectively enable / disable single decoders |
| with the options <code class="code">--enable-decoder=<var class="var">DECODER</var></code> / |
| <code class="code">--disable-decoder=<var class="var">DECODER</var></code>. |
| </p> |
| <p>The option <code class="code">-decoders</code> of the ff* tools will display the list of |
| enabled decoders. |
| </p> |
|
|
| <a name="Video-Decoders"></a> |
| <h2 class="chapter">4 Video Decoders<span class="pull-right"><a class="anchor hidden-xs" href="#Video-Decoders" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Video-Decoders" aria-hidden="true">TOC</a></span></h2> |
|
|
| <p>A description of some of the currently available video decoders |
| follows. |
| </p> |
| <a name="av1"></a> |
| <h3 class="section">4.1 av1<span class="pull-right"><a class="anchor hidden-xs" href="#av1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-av1" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>AOMedia Video 1 (AV1) decoder. |
| </p> |
| <a name="Options"></a> |
| <h4 class="subsection">4.1.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">operating_point</samp></dt> |
| <dd><p>Select an operating point of a scalable AV1 bitstream (0 - 31). Default is 0. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="hevc"></a> |
| <h3 class="section">4.2 hevc<span class="pull-right"><a class="anchor hidden-xs" href="#hevc" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-hevc" aria-hidden="true">TOC</a></span></h3> |
| <p>HEVC (AKA ITU-T H.265 or ISO/IEC 23008-2) decoder. |
| </p> |
| <p>The decoder supports MV-HEVC multiview streams with at most two views. Views to |
| be output are selected by supplying a list of view IDs to the decoder (the |
| <samp class="option">view_ids</samp> option). This option may be set either statically before |
| decoder init, or from the <code class="code">get_format()</code> callback - useful for the case |
| when the view count or IDs change dynamically during decoding. |
| </p> |
| <p>Only the base layer is decoded by default. |
| </p> |
| <p>Note that if you are using the <code class="code">ffmpeg</code> CLI tool, you should be using view |
| specifiers as documented in its manual, rather than the options documented here. |
| </p> |
| <a name="Options-1"></a> |
| <h4 class="subsection">4.2.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-1" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">view_ids (MV-HEVC)</samp></dt> |
| <dd><p>Specify a list of view IDs that should be output. This option can also be set to |
| a single ’-1’, which will cause all views defined in the VPS to be decoded and |
| output. |
| </p> |
| </dd> |
| <dt><samp class="option">view_ids_available (MV-HEVC)</samp></dt> |
| <dd><p>This option may be read by the caller to retrieve an array of view IDs available |
| in the active VPS. The array is empty for single-layer video. |
| </p> |
| <p>The value of this option is guaranteed to be accurate when read from the |
| <code class="code">get_format()</code> callback. It may also be set at other times (e.g. after |
| opening the decoder), but the value is informational only and may be incorrect |
| (e.g. when the stream contains multiple distinct VPS NALUs). |
| </p> |
| </dd> |
| <dt><samp class="option">view_pos_available (MV-HEVC)</samp></dt> |
| <dd><p>This option may be read by the caller to retrieve an array of view positions |
| (left, right, or unspecified) available in the active VPS, as |
| <code class="code">AVStereo3DView</code> values. When the array is available, its elements apply to |
| the corresponding elements of <samp class="option">view_ids_available</samp>, i.e. |
| <code class="code">view_pos_available[i]</code> contains the position of view with ID |
| <code class="code">view_ids_available[i]</code>. |
| </p> |
| <p>Same validity restrictions as for <samp class="option">view_ids_available</samp> apply to |
| this option. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="rawvideo"></a> |
| <h3 class="section">4.3 rawvideo<span class="pull-right"><a class="anchor hidden-xs" href="#rawvideo" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-rawvideo" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Raw video decoder. |
| </p> |
| <p>This decoder decodes rawvideo streams. |
| </p> |
| <a name="Options-2"></a> |
| <h4 class="subsection">4.3.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-2" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">top <var class="var">top_field_first</var></samp></dt> |
| <dd><p>Specify the assumed field type of the input video. |
| </p><dl class="table"> |
| <dt><samp class="option">-1</samp></dt> |
| <dd><p>the video is assumed to be progressive (default) |
| </p></dd> |
| <dt><samp class="option">0</samp></dt> |
| <dd><p>bottom-field-first is assumed |
| </p></dd> |
| <dt><samp class="option">1</samp></dt> |
| <dd><p>top-field-first is assumed |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
| <a name="libdav1d"></a> |
| <h3 class="section">4.4 libdav1d<span class="pull-right"><a class="anchor hidden-xs" href="#libdav1d" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libdav1d" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>dav1d AV1 decoder. |
| </p> |
| <p>libdav1d allows libavcodec to decode the AOMedia Video 1 (AV1) codec. |
| Requires the presence of the libdav1d headers and library during configuration. |
| You need to explicitly configure the build with <code class="code">--enable-libdav1d</code>. |
| </p> |
| <a name="Options-3"></a> |
| <h4 class="subsection">4.4.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-3" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-3" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following options are supported by the libdav1d wrapper. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">max_frame_delay</samp></dt> |
| <dd><p>Set max amount of frames the decoder may buffer internally. The default value is 0 |
| (autodetect). |
| </p> |
| </dd> |
| <dt><samp class="option">filmgrain</samp></dt> |
| <dd><p>Apply film grain to the decoded video if present in the bitstream. Defaults to the |
| internal default of the library. |
| This option is deprecated and will be removed in the future. See the global option |
| <code class="code">export_side_data</code> to export Film Grain parameters instead of applying it. |
| </p> |
| </dd> |
| <dt><samp class="option">oppoint</samp></dt> |
| <dd><p>Select an operating point of a scalable AV1 bitstream (0 - 31). Defaults to the |
| internal default of the library. |
| </p> |
| </dd> |
| <dt><samp class="option">alllayers</samp></dt> |
| <dd><p>Output all spatial layers of a scalable AV1 bitstream. The default value is false. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="libdavs2"></a> |
| <h3 class="section">4.5 libdavs2<span class="pull-right"><a class="anchor hidden-xs" href="#libdavs2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libdavs2" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>AVS2-P2/IEEE1857.4 video decoder wrapper. |
| </p> |
| <p>This decoder allows libavcodec to decode AVS2 streams with davs2 library. |
| </p> |
|
|
| <a name="libuavs3d"></a> |
| <h3 class="section">4.6 libuavs3d<span class="pull-right"><a class="anchor hidden-xs" href="#libuavs3d" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libuavs3d" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>AVS3-P2/IEEE1857.10 video decoder. |
| </p> |
| <p>libuavs3d allows libavcodec to decode AVS3 streams. |
| Requires the presence of the libuavs3d headers and library during configuration. |
| You need to explicitly configure the build with <code class="code">--enable-libuavs3d</code>. |
| </p> |
| <a name="Options-4"></a> |
| <h4 class="subsection">4.6.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-4" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-4" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following option is supported by the libuavs3d wrapper. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">frame_threads</samp></dt> |
| <dd><p>Set amount of frame threads to use during decoding. The default value is 0 (autodetect). |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="libxevd"></a> |
| <h3 class="section">4.7 libxevd<span class="pull-right"><a class="anchor hidden-xs" href="#libxevd" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libxevd" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>eXtra-fast Essential Video Decoder (XEVD) MPEG-5 EVC decoder wrapper. |
| </p> |
| <p>This decoder requires the presence of the libxevd headers and library |
| during configuration. You need to explicitly configure the build with |
| <samp class="option">--enable-libxevd</samp>. |
| </p> |
| <p>The xevd project website is at <a class="url" href="https://github.com/mpeg5/xevd">https://github.com/mpeg5/xevd</a>. |
| </p> |
| <a name="Options-5"></a> |
| <h4 class="subsection">4.7.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-5" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-5" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following options are supported by the libxevd wrapper. |
| The xevd-equivalent options or values are listed in parentheses for easy migration. |
| </p> |
| <p>To get a more accurate and extensive documentation of the libxevd options, |
| invoke the command <code class="code">xevd_app --help</code> or consult the libxevd documentation. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">threads (<em class="emph">threads</em>)</samp></dt> |
| <dd><p>Force to use a specific number of threads |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="QSV-Decoders"></a> |
| <h3 class="section">4.8 QSV Decoders<span class="pull-right"><a class="anchor hidden-xs" href="#QSV-Decoders" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-QSV-Decoders" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>The family of Intel QuickSync Video decoders (VC1, MPEG-2, H.264, HEVC, |
| JPEG/MJPEG, VP8, VP9, AV1, VVC). |
| </p> |
| <a name="Common-Options"></a> |
| <h4 class="subsection">4.8.1 Common Options<span class="pull-right"><a class="anchor hidden-xs" href="#Common-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Common-Options" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following options are supported by all qsv decoders. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option"><var class="var">async_depth</var></samp></dt> |
| <dd><p>Internal parallelization depth, the higher the value the higher the latency. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">gpu_copy</var></samp></dt> |
| <dd><p>A GPU-accelerated copy between video and system memory |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">default</samp>’</dt> |
| <dt>‘<samp class="samp">on</samp>’</dt> |
| <dt>‘<samp class="samp">off</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
| <a name="HEVC-Options"></a> |
| <h4 class="subsection">4.8.2 HEVC Options<span class="pull-right"><a class="anchor hidden-xs" href="#HEVC-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-HEVC-Options" aria-hidden="true">TOC</a></span></h4> |
| <p>Extra options for hevc_qsv. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option"><var class="var">load_plugin</var></samp></dt> |
| <dd><p>A user plugin to load in an internal session |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">none</samp>’</dt> |
| <dt>‘<samp class="samp">hevc_sw</samp>’</dt> |
| <dt>‘<samp class="samp">hevc_hw</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option"><var class="var">load_plugins</var></samp></dt> |
| <dd><p>A :-separate list of hexadecimal plugin UIDs to load in an internal session |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="v210"></a> |
| <h3 class="section">4.9 v210<span class="pull-right"><a class="anchor hidden-xs" href="#v210" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-v210" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Uncompressed 4:2:2 10-bit decoder. |
| </p> |
| <a name="Options-6"></a> |
| <h4 class="subsection">4.9.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-6" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-6" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">custom_stride</samp></dt> |
| <dd><p>Set the line size of the v210 data in bytes. The default value is 0 |
| (autodetect). You can use the special -1 value for a strideless v210 as seen in |
| BOXX files. |
| </p> |
| </dd> |
| </dl> |
|
|
|
|
| <a name="Audio-Decoders"></a> |
| <h2 class="chapter">5 Audio Decoders<span class="pull-right"><a class="anchor hidden-xs" href="#Audio-Decoders" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Audio-Decoders" aria-hidden="true">TOC</a></span></h2> |
|
|
| <p>A description of some of the currently available audio decoders |
| follows. |
| </p> |
| <a name="ac3"></a> |
| <h3 class="section">5.1 ac3<span class="pull-right"><a class="anchor hidden-xs" href="#ac3" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-ac3" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>AC-3 audio decoder. |
| </p> |
| <p>This decoder implements part of ATSC A/52:2010 and ETSI TS 102 366, as well as |
| the undocumented RealAudio 3 (a.k.a. dnet). |
| </p> |
| <a name="AC_002d3-Decoder-Options"></a> |
| <h4 class="subsection">5.1.1 AC-3 Decoder Options<span class="pull-right"><a class="anchor hidden-xs" href="#AC_002d3-Decoder-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-AC_002d3-Decoder-Options" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">-drc_scale <var class="var">value</var></samp></dt> |
| <dd><p>Dynamic Range Scale Factor. The factor to apply to dynamic range values |
| from the AC-3 stream. This factor is applied exponentially. The default value is 1. |
| There are 3 notable scale factor ranges: |
| </p><dl class="table"> |
| <dt><samp class="option">drc_scale == 0</samp></dt> |
| <dd><p>DRC disabled. Produces full range audio. |
| </p></dd> |
| <dt><samp class="option">0 < drc_scale <= 1</samp></dt> |
| <dd><p>DRC enabled. Applies a fraction of the stream DRC value. |
| Audio reproduction is between full range and full compression. |
| </p></dd> |
| <dt><samp class="option">drc_scale > 1</samp></dt> |
| <dd><p>DRC enabled. Applies drc_scale asymmetrically. |
| Loud sounds are fully compressed. Soft sounds are enhanced. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
| <a name="flac-1"></a> |
| <h3 class="section">5.2 flac<span class="pull-right"><a class="anchor hidden-xs" href="#flac-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-flac-1" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>FLAC audio decoder. |
| </p> |
| <p>This decoder aims to implement the complete FLAC specification from Xiph. |
| </p> |
| <a name="FLAC-Decoder-options"></a> |
| <h4 class="subsection">5.2.1 FLAC Decoder options<span class="pull-right"><a class="anchor hidden-xs" href="#FLAC-Decoder-options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-FLAC-Decoder-options" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">-use_buggy_lpc</samp></dt> |
| <dd><p>The lavc FLAC encoder used to produce buggy streams with high lpc values |
| (like the default value). This option makes it possible to decode such streams |
| correctly by using lavc’s old buggy lpc logic for decoding. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="ffwavesynth"></a> |
| <h3 class="section">5.3 ffwavesynth<span class="pull-right"><a class="anchor hidden-xs" href="#ffwavesynth" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-ffwavesynth" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Internal wave synthesizer. |
| </p> |
| <p>This decoder generates wave patterns according to predefined sequences. Its |
| use is purely internal and the format of the data it accepts is not publicly |
| documented. |
| </p> |
| <a name="libcelt"></a> |
| <h3 class="section">5.4 libcelt<span class="pull-right"><a class="anchor hidden-xs" href="#libcelt" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libcelt" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>libcelt decoder wrapper. |
| </p> |
| <p>libcelt allows libavcodec to decode the Xiph CELT ultra-low delay audio codec. |
| Requires the presence of the libcelt headers and library during configuration. |
| You need to explicitly configure the build with <code class="code">--enable-libcelt</code>. |
| </p> |
| <a name="libgsm"></a> |
| <h3 class="section">5.5 libgsm<span class="pull-right"><a class="anchor hidden-xs" href="#libgsm" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libgsm" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>libgsm decoder wrapper. |
| </p> |
| <p>libgsm allows libavcodec to decode the GSM full rate audio codec. Requires |
| the presence of the libgsm headers and library during configuration. You need |
| to explicitly configure the build with <code class="code">--enable-libgsm</code>. |
| </p> |
| <p>This decoder supports both the ordinary GSM and the Microsoft variant. |
| </p> |
| <a name="libilbc"></a> |
| <h3 class="section">5.6 libilbc<span class="pull-right"><a class="anchor hidden-xs" href="#libilbc" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libilbc" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>libilbc decoder wrapper. |
| </p> |
| <p>libilbc allows libavcodec to decode the Internet Low Bitrate Codec (iLBC) |
| audio codec. Requires the presence of the libilbc headers and library during |
| configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libilbc</code>. |
| </p> |
| <a name="Options-7"></a> |
| <h4 class="subsection">5.6.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-7" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-7" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following option is supported by the libilbc wrapper. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">enhance</samp></dt> |
| <dd> |
| <p>Enable the enhancement of the decoded audio when set to 1. The default |
| value is 0 (disabled). |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="libmpeghdec"></a> |
| <h3 class="section">5.7 libmpeghdec<span class="pull-right"><a class="anchor hidden-xs" href="#libmpeghdec" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libmpeghdec" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>libmpeghdec decoder wrapper. |
| </p> |
| <p>libmpeghdec allows libmpeghdec to decode the MPEG-H 3D audio codec. |
| Requires the presence of the libmpeghdec headers and library during |
| configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libmpeghdec --enable-nonfree</code>. |
| </p> |
| <a name="libopencore_002damrnb"></a> |
| <h3 class="section">5.8 libopencore-amrnb<span class="pull-right"><a class="anchor hidden-xs" href="#libopencore_002damrnb" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libopencore_002damrnb" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>libopencore-amrnb decoder wrapper. |
| </p> |
| <p>libopencore-amrnb allows libavcodec to decode the Adaptive Multi-Rate |
| Narrowband audio codec. Using it requires the presence of the |
| libopencore-amrnb headers and library during configuration. You need to |
| explicitly configure the build with <code class="code">--enable-libopencore-amrnb</code>. |
| </p> |
| <p>An FFmpeg native decoder for AMR-NB exists, so users can decode AMR-NB |
| without this library. |
| </p> |
| <a name="libopencore_002damrwb"></a> |
| <h3 class="section">5.9 libopencore-amrwb<span class="pull-right"><a class="anchor hidden-xs" href="#libopencore_002damrwb" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libopencore_002damrwb" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>libopencore-amrwb decoder wrapper. |
| </p> |
| <p>libopencore-amrwb allows libavcodec to decode the Adaptive Multi-Rate |
| Wideband audio codec. Using it requires the presence of the |
| libopencore-amrwb headers and library during configuration. You need to |
| explicitly configure the build with <code class="code">--enable-libopencore-amrwb</code>. |
| </p> |
| <p>An FFmpeg native decoder for AMR-WB exists, so users can decode AMR-WB |
| without this library. |
| </p> |
| <a name="libopus"></a> |
| <h3 class="section">5.10 libopus<span class="pull-right"><a class="anchor hidden-xs" href="#libopus" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libopus" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>libopus decoder wrapper. |
| </p> |
| <p>libopus allows libavcodec to decode the Opus Interactive Audio Codec. |
| Requires the presence of the libopus headers and library during |
| configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libopus</code>. |
| </p> |
| <p>An FFmpeg native decoder for Opus exists, so users can decode Opus |
| without this library. |
| </p> |
|
|
| <a name="Subtitles-Decoders"></a> |
| <h2 class="chapter">6 Subtitles Decoders<span class="pull-right"><a class="anchor hidden-xs" href="#Subtitles-Decoders" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Subtitles-Decoders" aria-hidden="true">TOC</a></span></h2> |
|
|
| <a name="libaribb24"></a> |
| <h3 class="section">6.1 libaribb24<span class="pull-right"><a class="anchor hidden-xs" href="#libaribb24" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libaribb24" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>ARIB STD-B24 caption decoder. |
| </p> |
| <p>Implements profiles A and C of the ARIB STD-B24 standard. |
| </p> |
| <a name="libaribb24-Decoder-Options"></a> |
| <h4 class="subsection">6.1.1 libaribb24 Decoder Options<span class="pull-right"><a class="anchor hidden-xs" href="#libaribb24-Decoder-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libaribb24-Decoder-Options" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">-aribb24-base-path <var class="var">path</var></samp></dt> |
| <dd><p>Sets the base path for the libaribb24 library. This is utilized for reading of |
| configuration files (for custom unicode conversions), and for dumping of |
| non-text symbols as images under that location. |
| </p> |
| <p>Unset by default. |
| </p> |
| </dd> |
| <dt><samp class="option">-aribb24-skip-ruby-text <var class="var">boolean</var></samp></dt> |
| <dd><p>Tells the decoder wrapper to skip text blocks that contain half-height ruby |
| text. |
| </p> |
| <p>Enabled by default. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="libaribcaption"></a> |
| <h3 class="section">6.2 libaribcaption<span class="pull-right"><a class="anchor hidden-xs" href="#libaribcaption" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libaribcaption" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Yet another ARIB STD-B24 caption decoder using external <em class="dfn">libaribcaption</em> |
| library. |
| </p> |
| <p>Implements profiles A and C of the Japanese ARIB STD-B24 standard, |
| Brazilian ABNT NBR 15606-1, and Philippines version of ISDB-T. |
| </p> |
| <p>Requires the presence of the libaribcaption headers and library |
| (<a class="url" href="https://github.com/xqq/libaribcaption">https://github.com/xqq/libaribcaption</a>) during configuration. |
| You need to explicitly configure the build with <code class="code">--enable-libaribcaption</code>. |
| If both <em class="dfn">libaribb24</em> and <em class="dfn">libaribcaption</em> are enabled, <em class="dfn">libaribcaption</em> |
| decoder precedes. |
| </p> |
| <a name="libaribcaption-Decoder-Options"></a> |
| <h4 class="subsection">6.2.1 libaribcaption Decoder Options<span class="pull-right"><a class="anchor hidden-xs" href="#libaribcaption-Decoder-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libaribcaption-Decoder-Options" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">-sub_type <var class="var">subtitle_type</var></samp></dt> |
| <dd><p>Specifies the format of the decoded subtitles. |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">bitmap</samp>’</dt> |
| <dd><p>Graphical image. |
| </p></dd> |
| <dt>‘<samp class="samp">ass</samp>’</dt> |
| <dd><p>ASS formatted text. |
| </p></dd> |
| <dt>‘<samp class="samp">text</samp>’</dt> |
| <dd><p>Simple text based output without formatting. |
| </p></dd> |
| </dl> |
|
|
| <p>The default is <em class="dfn">ass</em> as same as <em class="dfn">libaribb24</em> decoder. |
| Some present players (e.g., <em class="dfn">mpv</em>) expect ASS format for ARIB caption. |
| </p> |
| </dd> |
| <dt><samp class="option">-caption_encoding <var class="var">encoding_scheme</var></samp></dt> |
| <dd><p>Specifies the encoding scheme of input subtitle text. |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">auto</samp>’</dt> |
| <dd><p>Automatically detect text encoding (default). |
| </p></dd> |
| <dt>‘<samp class="samp">jis</samp>’</dt> |
| <dd><p>8bit-char JIS encoding defined in ARIB STD B24. |
| This encoding used in Japan for ISDB captions. |
| </p></dd> |
| <dt>‘<samp class="samp">utf8</samp>’</dt> |
| <dd><p>UTF-8 encoding defined in ARIB STD B24. |
| This encoding is used in Philippines for ISDB-T captions. |
| </p></dd> |
| <dt>‘<samp class="samp">latin</samp>’</dt> |
| <dd><p>Latin character encoding defined in ABNT NBR 15606-1. |
| This encoding is used in South America for SBTVD / ISDB-Tb captions. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">-font <var class="var">font_name[,font_name2,...]</var></samp></dt> |
| <dd><p>Specify comma-separated list of font family names to be used for <em class="dfn">bitmap</em> |
| or <em class="dfn">ass</em> type subtitle rendering. |
| Only first font name is used for <em class="dfn">ass</em> type subtitle. |
| </p> |
| <p>If not specified, use internally defined default font family. |
| </p> |
| </dd> |
| <dt><samp class="option">-ass_single_rect <var class="var">boolean</var></samp></dt> |
| <dd><p>ARIB STD-B24 specifies that some captions may be displayed at different |
| positions at a time (multi-rectangle subtitle). |
| Since some players (e.g., old <em class="dfn">mpv</em>) can’t handle multiple ASS rectangles |
| in a single AVSubtitle, or multiple ASS rectangles of indeterminate duration |
| with the same start timestamp, this option can change the behavior so that |
| all the texts are displayed in a single ASS rectangle. |
| </p> |
| <p>The default is <var class="var">false</var>. |
| </p> |
| <p>If your player cannot handle AVSubtitles with multiple ASS rectangles properly, |
| set this option to <var class="var">true</var> or define <code class="env">ASS_SINGLE_RECT=1</code> to change |
| default behavior at compilation. |
| </p> |
| </dd> |
| <dt><samp class="option">-force_outline_text <var class="var">boolean</var></samp></dt> |
| <dd><p>Specify whether always render outline text for all characters regardless of |
| the indication by character style. |
| </p> |
| <p>The default is <var class="var">false</var>. |
| </p> |
| </dd> |
| <dt><samp class="option">-outline_width <var class="var">number</var> (0.0 - 3.0)</samp></dt> |
| <dd><p>Specify width for outline text, in dots (relative). |
| </p> |
| <p>The default is <var class="var">1.5</var>. |
| </p> |
| </dd> |
| <dt><samp class="option">-ignore_background <var class="var">boolean</var></samp></dt> |
| <dd><p>Specify whether to ignore background color rendering. |
| </p> |
| <p>The default is <var class="var">false</var>. |
| </p> |
| </dd> |
| <dt><samp class="option">-ignore_ruby <var class="var">boolean</var></samp></dt> |
| <dd><p>Specify whether to ignore rendering for ruby-like (furigana) characters. |
| </p> |
| <p>The default is <var class="var">false</var>. |
| </p> |
| </dd> |
| <dt><samp class="option">-replace_drcs <var class="var">boolean</var></samp></dt> |
| <dd><p>Specify whether to render replaced DRCS characters as Unicode characters. |
| </p> |
| <p>The default is <var class="var">true</var>. |
| </p> |
| </dd> |
| <dt><samp class="option">-replace_msz_ascii <var class="var">boolean</var></samp></dt> |
| <dd><p>Specify whether to replace MSZ (Middle Size; half width) fullwidth |
| alphanumerics with halfwidth alphanumerics. |
| </p> |
| <p>The default is <var class="var">true</var>. |
| </p> |
| </dd> |
| <dt><samp class="option">-replace_msz_japanese <var class="var">boolean</var></samp></dt> |
| <dd><p>Specify whether to replace some MSZ (Middle Size; half width) fullwidth |
| japanese special characters with halfwidth ones. |
| </p> |
| <p>The default is <var class="var">true</var>. |
| </p> |
| </dd> |
| <dt><samp class="option">-replace_msz_glyph <var class="var">boolean</var></samp></dt> |
| <dd><p>Specify whether to replace MSZ (Middle Size; half width) characters |
| with halfwidth glyphs if the fonts supports it. |
| This option works under FreeType or DirectWrite renderer |
| with Adobe-Japan1 compliant fonts. |
| e.g., IBM Plex Sans JP, Morisawa BIZ UDGothic, Morisawa BIZ UDMincho, |
| Yu Gothic, Yu Mincho, and Meiryo. |
| </p> |
| <p>The default is <var class="var">true</var>. |
| </p> |
| </dd> |
| <dt><samp class="option">-canvas_size <var class="var">image_size</var></samp></dt> |
| <dd><p>Specify the resolution of the canvas to render subtitles to; usually, this |
| should be frame size of input video. |
| This only applies when <code class="code">-subtitle_type</code> is set to <var class="var">bitmap</var>. |
| </p> |
| <p>The libaribcaption decoder assumes input frame size for bitmap rendering as below: |
| </p><ol class="enumerate"> |
| <li> PROFILE_A : 1440 x 1080 with SAR (PAR) 4:3 |
| </li><li> PROFILE_C : 320 x 180 with SAR (PAR) 1:1 |
| </li></ol> |
|
|
| <p>If actual frame size of input video does not match above assumption, |
| the rendered captions may be distorted. |
| To make the captions undistorted, add <code class="code">-canvas_size</code> option to specify |
| actual input video size. |
| </p> |
| <p>Note that the <code class="code">-canvas_size</code> option is not required for video with |
| different size but same aspect ratio. |
| In such cases, the caption will be stretched or shrunk to actual video size |
| if <code class="code">-canvas_size</code> option is not specified. |
| If <code class="code">-canvas_size</code> option is specified with different size, |
| the caption will be stretched or shrunk as specified size with calculated SAR. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="libaribcaption-decoder-usage-examples"></a> |
| <h4 class="subsection">6.2.2 libaribcaption decoder usage examples<span class="pull-right"><a class="anchor hidden-xs" href="#libaribcaption-decoder-usage-examples" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libaribcaption-decoder-usage-examples" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>Display MPEG-TS file with ARIB subtitle by <code class="code">ffplay</code> tool: |
| </p><div class="example"> |
| <pre class="example-preformatted">ffplay -sub_type bitmap MPEG.TS |
| </pre></div> |
|
|
| <p>Display MPEG-TS file with input frame size 1920x1080 by <code class="code">ffplay</code> tool: |
| </p><div class="example"> |
| <pre class="example-preformatted">ffplay -sub_type bitmap -canvas_size 1920x1080 MPEG.TS |
| </pre></div> |
|
|
| <p>Embed ARIB subtitle in transcoded video: |
| </p><div class="example"> |
| <pre class="example-preformatted">ffmpeg -sub_type bitmap -i src.m2t -filter_complex "[0:v][0:s]overlay" -vcodec h264 dest.mp4 |
| </pre></div> |
|
|
| <a name="dvbsub"></a> |
| <h3 class="section">6.3 dvbsub<span class="pull-right"><a class="anchor hidden-xs" href="#dvbsub" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-dvbsub" aria-hidden="true">TOC</a></span></h3> |
|
|
| <a name="Options-8"></a> |
| <h4 class="subsection">6.3.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-8" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-8" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">compute_clut</samp></dt> |
| <dd><dl class="table"> |
| <dt><samp class="option">-2</samp></dt> |
| <dd><p>Compute clut once if no matching CLUT is in the stream. |
| </p></dd> |
| <dt><samp class="option">-1</samp></dt> |
| <dd><p>Compute clut if no matching CLUT is in the stream. |
| </p></dd> |
| <dt><samp class="option">0</samp></dt> |
| <dd><p>Never compute CLUT |
| </p></dd> |
| <dt><samp class="option">1</samp></dt> |
| <dd><p>Always compute CLUT and override the one provided in the stream. |
| </p></dd> |
| </dl> |
| </dd> |
| <dt><samp class="option">dvb_substream</samp></dt> |
| <dd><p>Selects the dvb substream, or all substreams if -1 which is default. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="dvdsub"></a> |
| <h3 class="section">6.4 dvdsub<span class="pull-right"><a class="anchor hidden-xs" href="#dvdsub" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-dvdsub" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>This codec decodes the bitmap subtitles used in DVDs; the same subtitles can |
| also be found in VobSub file pairs and in some Matroska files. |
| </p> |
| <a name="Options-9"></a> |
| <h4 class="subsection">6.4.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-9" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-9" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">palette</samp></dt> |
| <dd><p>Specify the global palette used by the bitmaps. When stored in VobSub, the |
| palette is normally specified in the index file; in Matroska, the palette is |
| stored in the codec extra-data in the same format as in VobSub. In DVDs, the |
| palette is stored in the IFO file, and therefore not available when reading |
| from dumped VOB files. |
| </p> |
| <p>The format for this option is a string containing 16 24-bits hexadecimal |
| numbers (without 0x prefix) separated by commas, for example <code class="code">0d00ee, |
| ee450d, 101010, eaeaea, 0ce60b, ec14ed, ebff0b, 0d617a, 7b7b7b, d1d1d1, |
| 7b2a0e, 0d950c, 0f007b, cf0dec, cfa80c, 7c127b</code>. |
| </p> |
| </dd> |
| <dt><samp class="option">ifo_palette</samp></dt> |
| <dd><p>Specify the IFO file from which the global palette is obtained. |
| (experimental) |
| </p> |
| </dd> |
| <dt><samp class="option">forced_subs_only</samp></dt> |
| <dd><p>Only decode subtitle entries marked as forced. Some titles have forced |
| and non-forced subtitles in the same track. Setting this flag to <code class="code">1</code> |
| will only keep the forced subtitles. Default value is <code class="code">0</code>. |
| </p></dd> |
| </dl> |
|
|
| <a name="libzvbi_002dteletext"></a> |
| <h3 class="section">6.5 libzvbi-teletext<span class="pull-right"><a class="anchor hidden-xs" href="#libzvbi_002dteletext" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libzvbi_002dteletext" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Libzvbi allows libavcodec to decode DVB teletext pages and DVB teletext |
| subtitles. Requires the presence of the libzvbi headers and library during |
| configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libzvbi</code>. |
| </p> |
| <a name="Options-10"></a> |
| <h4 class="subsection">6.5.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-10" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-10" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">txt_page</samp></dt> |
| <dd><p>List of teletext page numbers to decode. Pages that do not match the specified |
| list are dropped. You may use the special <code class="code">*</code> string to match all pages, |
| or <code class="code">subtitle</code> to match all subtitle pages. |
| Default value is *. |
| </p></dd> |
| <dt><samp class="option">txt_default_region</samp></dt> |
| <dd><p>Set default character set used for decoding, a value between 0 and 87 (see |
| ETS 300 706, Section 15, Table 32). Default value is -1, which does not |
| override the libzvbi default. This option is needed for some legacy level 1.0 |
| transmissions which cannot signal the proper charset. |
| </p></dd> |
| <dt><samp class="option">txt_chop_top</samp></dt> |
| <dd><p>Discards the top teletext line. Default value is 1. |
| </p></dd> |
| <dt><samp class="option">txt_format</samp></dt> |
| <dd><p>Specifies the format of the decoded subtitles. |
| </p><dl class="table"> |
| <dt><samp class="option">bitmap</samp></dt> |
| <dd><p>The default format, you should use this for teletext pages, because certain |
| graphics and colors cannot be expressed in simple text or even ASS. |
| </p></dd> |
| <dt><samp class="option">text</samp></dt> |
| <dd><p>Simple text based output without formatting. |
| </p></dd> |
| <dt><samp class="option">ass</samp></dt> |
| <dd><p>Formatted ASS output, subtitle pages and teletext pages are returned in |
| different styles, subtitle pages are stripped down to text, but an effort is |
| made to keep the text alignment and the formatting. |
| </p></dd> |
| </dl> |
| </dd> |
| <dt><samp class="option">txt_left</samp></dt> |
| <dd><p>X offset of generated bitmaps, default is 0. |
| </p></dd> |
| <dt><samp class="option">txt_top</samp></dt> |
| <dd><p>Y offset of generated bitmaps, default is 0. |
| </p></dd> |
| <dt><samp class="option">txt_chop_spaces</samp></dt> |
| <dd><p>Chops leading and trailing spaces and removes empty lines from the generated |
| text. This option is useful for teletext based subtitles where empty spaces may |
| be present at the start or at the end of the lines or empty lines may be |
| present between the subtitle lines because of double-sized teletext characters. |
| Default value is 1. |
| </p></dd> |
| <dt><samp class="option">txt_duration</samp></dt> |
| <dd><p>Sets the display duration of the decoded teletext pages or subtitles in |
| milliseconds. Default value is -1 which means infinity or until the next |
| subtitle event comes. |
| </p></dd> |
| <dt><samp class="option">txt_transparent</samp></dt> |
| <dd><p>Force transparent background of the generated teletext bitmaps. Default value |
| is 0 which means an opaque background. |
| </p></dd> |
| <dt><samp class="option">txt_opacity</samp></dt> |
| <dd><p>Sets the opacity (0-255) of the teletext background. If |
| <samp class="option">txt_transparent</samp> is not set, it only affects characters between a start |
| box and an end box, typically subtitles. Default value is 0 if |
| <samp class="option">txt_transparent</samp> is set, 255 otherwise. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="Encoders"></a> |
| <h2 class="chapter">7 Encoders<span class="pull-right"><a class="anchor hidden-xs" href="#Encoders" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Encoders" aria-hidden="true">TOC</a></span></h2> |
|
|
| <p>Encoders are configured elements in FFmpeg which allow the encoding of |
| multimedia streams. |
| </p> |
| <p>When you configure your FFmpeg build, all the supported native encoders |
| are enabled by default. Encoders requiring an external library must be enabled |
| manually via the corresponding <code class="code">--enable-lib</code> option. You can list all |
| available encoders using the configure option <code class="code">--list-encoders</code>. |
| </p> |
| <p>You can disable all the encoders with the configure option |
| <code class="code">--disable-encoders</code> and selectively enable / disable single encoders |
| with the options <code class="code">--enable-encoder=<var class="var">ENCODER</var></code> / |
| <code class="code">--disable-encoder=<var class="var">ENCODER</var></code>. |
| </p> |
| <p>The option <code class="code">-encoders</code> of the ff* tools will display the list of |
| enabled encoders. |
| </p> |
|
|
| <a name="Audio-Encoders"></a> |
| <h2 class="chapter">8 Audio Encoders<span class="pull-right"><a class="anchor hidden-xs" href="#Audio-Encoders" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Audio-Encoders" aria-hidden="true">TOC</a></span></h2> |
|
|
| <p>A description of some of the currently available audio encoders |
| follows. |
| </p> |
| <a class="anchor" id="aacenc"></a><a name="aac"></a> |
| <h3 class="section">8.1 aac<span class="pull-right"><a class="anchor hidden-xs" href="#aac" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-aac" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Advanced Audio Coding (AAC) encoder. |
| </p> |
| <p>This encoder is the default AAC encoder, natively implemented into FFmpeg. |
| </p> |
| <a name="Options-11"></a> |
| <h4 class="subsection">8.1.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-11" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-11" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">b</samp></dt> |
| <dd><p>Set bit rate in bits/s. Setting this automatically activates constant bit rate |
| (CBR) mode. If this option is unspecified it is set to 128kbps. |
| </p> |
| </dd> |
| <dt><samp class="option">q</samp></dt> |
| <dd><p>Set quality for variable bit rate (VBR) mode. This option is valid only using |
| the <code class="command">ffmpeg</code> command-line tool. For library interface users, use |
| <samp class="option">global_quality</samp>. |
| </p> |
| </dd> |
| <dt><samp class="option">cutoff</samp></dt> |
| <dd><p>Set cutoff frequency. If unspecified will allow the encoder to dynamically |
| adjust the cutoff to improve clarity on low bitrates. |
| </p> |
| </dd> |
| <dt><samp class="option">aac_coder</samp></dt> |
| <dd><p>Set AAC encoder coding method. Possible values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">twoloop</samp>’</dt> |
| <dd><p>Two loop searching (TLS) method. This is the default method. |
| </p> |
| <p>This method first sets quantizers depending on band thresholds and then tries |
| to find an optimal combination by adding or subtracting a specific value from |
| all quantizers and adjusting some individual quantizer a little. Will tune |
| itself based on whether <samp class="option">aac_is</samp>, <samp class="option">aac_ms</samp> and <samp class="option">aac_pns</samp> |
| are enabled. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">anmr</samp>’</dt> |
| <dd><p>Average noise to mask ratio (ANMR) trellis-based solution. |
| </p> |
| <p>This is an experimental coder which currently produces a lower quality, is more |
| unstable and is slower than the default twoloop coder but has potential. |
| Currently has no support for the <samp class="option">aac_is</samp> or <samp class="option">aac_pns</samp> options. |
| Not currently recommended. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">fast</samp>’</dt> |
| <dd><p>Constant quantizer method. |
| </p> |
| <p>Uses a cheaper version of twoloop algorithm that doesn’t try to do as many |
| clever adjustments. Worse with low bitrates (less than 64kbps), but is better |
| and much faster at higher bitrates. |
| </p> |
| </dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">aac_ms</samp></dt> |
| <dd><p>Sets mid/side coding mode. The default value of "auto" will automatically use |
| M/S with bands which will benefit from such coding. Can be forced for all bands |
| using the value "enable", which is mainly useful for debugging or disabled using |
| "disable". |
| </p> |
| </dd> |
| <dt><samp class="option">aac_is</samp></dt> |
| <dd><p>Sets intensity stereo coding tool usage. By default, it’s enabled and will |
| automatically toggle IS for similar pairs of stereo bands if it’s beneficial. |
| Can be disabled for debugging by setting the value to "disable". |
| </p> |
| </dd> |
| <dt><samp class="option">aac_pns</samp></dt> |
| <dd><p>Uses perceptual noise substitution to replace low entropy high frequency bands |
| with imperceptible white noise during the decoding process. By default, it’s |
| enabled, but can be disabled for debugging purposes by using "disable". |
| </p> |
| </dd> |
| <dt><samp class="option">aac_tns</samp></dt> |
| <dd><p>Enables the use of a multitap FIR filter which spans through the high frequency |
| bands to hide quantization noise during the encoding process and is reverted |
| by the decoder. As well as decreasing unpleasant artifacts in the high range |
| this also reduces the entropy in the high bands and allows for more bits to |
| be used by the mid-low bands. By default it’s enabled but can be disabled for |
| debugging by setting the option to "disable". |
| </p> |
| </dd> |
| <dt><samp class="option">aac_ltp</samp></dt> |
| <dd><p>Enables the use of the long term prediction extension which increases coding |
| efficiency in very low bandwidth situations such as encoding of voice or |
| solo piano music by extending constant harmonic peaks in bands throughout |
| frames. This option is implied by profile:a aac_low. |
| Use in conjunction with <samp class="option">-ar</samp> to decrease the samplerate. |
| </p> |
| </dd> |
| <dt><samp class="option">profile</samp></dt> |
| <dd><p>Sets the encoding profile, possible values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">aac_low</samp>’</dt> |
| <dd><p>The default, AAC "Low-complexity" profile. Is the most compatible and produces |
| decent quality. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">mpeg2_aac_low</samp>’</dt> |
| <dd><p>Equivalent to <code class="code">-profile:a aac_low -aac_pns 0</code>. PNS was introduced with the |
| MPEG4 specifications. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">aac_ltp</samp>’</dt> |
| <dd><p>Long term prediction profile, is enabled by and will enable the <samp class="option">aac_ltp</samp> |
| option. Introduced in MPEG4. |
| </p> |
| </dd> |
| </dl> |
| <p>If this option is unspecified it is set to ‘<samp class="samp">aac_low</samp>’. |
| </p></dd> |
| </dl> |
|
|
| <a name="ac3-and-ac3_005ffixed"></a> |
| <h3 class="section">8.2 ac3 and ac3_fixed<span class="pull-right"><a class="anchor hidden-xs" href="#ac3-and-ac3_005ffixed" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-ac3-and-ac3_005ffixed" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>AC-3 audio encoders. |
| </p> |
| <p>These encoders implement part of ATSC A/52:2010 and ETSI TS 102 366. |
| </p> |
| <p>The <var class="var">ac3</var> encoder uses floating-point math, while the <var class="var">ac3_fixed</var> |
| encoder only uses fixed-point integer math. This does not mean that one is |
| always faster, just that one or the other may be better suited to a |
| particular system. The <var class="var">ac3_fixed</var> encoder is not the default codec for |
| any of the output formats, so it must be specified explicitly using the option |
| <code class="code">-acodec ac3_fixed</code> in order to use it. |
| </p> |
| <a name="AC_002d3-Metadata"></a> |
| <h4 class="subsection">8.2.1 AC-3 Metadata<span class="pull-right"><a class="anchor hidden-xs" href="#AC_002d3-Metadata" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-AC_002d3-Metadata" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The AC-3 metadata options are used to set parameters that describe the audio, |
| but in most cases do not affect the audio encoding itself. Some of the options |
| do directly affect or influence the decoding and playback of the resulting |
| bitstream, while others are just for informational purposes. A few of the |
| options will add bits to the output stream that could otherwise be used for |
| audio data, and will thus affect the quality of the output. Those will be |
| indicated accordingly with a note in the option list below. |
| </p> |
| <p>These parameters are described in detail in several publicly-available |
| documents. |
| </p><ul class="itemize mark-bullet"> |
| <li><a class="uref" href="http://www.atsc.org/cms/standards/a_52-2010.pdf">A/52:2010 - Digital Audio Compression (AC-3) (E-AC-3) Standard</a> |
| </li><li><a class="uref" href="http://www.atsc.org/cms/standards/a_54a_with_corr_1.pdf">A/54 - Guide to the Use of the ATSC Digital Television Standard</a> |
| </li><li><a class="uref" href="http://www.dolby.com/uploadedFiles/zz-_Shared_Assets/English_PDFs/Professional/18_Metadata.Guide.pdf">Dolby Metadata Guide</a> |
| </li><li><a class="uref" href="http://www.dolby.com/uploadedFiles/zz-_Shared_Assets/English_PDFs/Professional/46_DDEncodingGuidelines.pdf">Dolby Digital Professional Encoding Guidelines</a> |
| </li></ul> |
|
|
| <a name="Metadata-Control-Options"></a> |
| <h4 class="subsubsection">8.2.1.1 Metadata Control Options<span class="pull-right"><a class="anchor hidden-xs" href="#Metadata-Control-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Metadata-Control-Options" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">-per_frame_metadata <var class="var">boolean</var></samp></dt> |
| <dd><p>Allow Per-Frame Metadata. Specifies if the encoder should check for changing |
| metadata for each frame. |
| </p><dl class="table"> |
| <dt><samp class="option">0</samp></dt> |
| <dd><p>The metadata values set at initialization will be used for every frame in the |
| stream. (default) |
| </p></dd> |
| <dt><samp class="option">1</samp></dt> |
| <dd><p>Metadata values can be changed before encoding each frame. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
| <a name="Downmix-Levels"></a> |
| <h4 class="subsubsection">8.2.1.2 Downmix Levels<span class="pull-right"><a class="anchor hidden-xs" href="#Downmix-Levels" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Downmix-Levels" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">-center_mixlev <var class="var">level</var></samp></dt> |
| <dd><p>Center Mix Level. The amount of gain the decoder should apply to the center |
| channel when downmixing to stereo. This field will only be written to the |
| bitstream if a center channel is present. The value is specified as a scale |
| factor. There are 3 valid values: |
| </p><dl class="table"> |
| <dt><samp class="option">0.707</samp></dt> |
| <dd><p>Apply -3dB gain |
| </p></dd> |
| <dt><samp class="option">0.595</samp></dt> |
| <dd><p>Apply -4.5dB gain (default) |
| </p></dd> |
| <dt><samp class="option">0.500</samp></dt> |
| <dd><p>Apply -6dB gain |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">-surround_mixlev <var class="var">level</var></samp></dt> |
| <dd><p>Surround Mix Level. The amount of gain the decoder should apply to the surround |
| channel(s) when downmixing to stereo. This field will only be written to the |
| bitstream if one or more surround channels are present. The value is specified |
| as a scale factor. There are 3 valid values: |
| </p><dl class="table"> |
| <dt><samp class="option">0.707</samp></dt> |
| <dd><p>Apply -3dB gain |
| </p></dd> |
| <dt><samp class="option">0.500</samp></dt> |
| <dd><p>Apply -6dB gain (default) |
| </p></dd> |
| <dt><samp class="option">0.000</samp></dt> |
| <dd><p>Silence Surround Channel(s) |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
| <a name="Audio-Production-Information"></a> |
| <h4 class="subsubsection">8.2.1.3 Audio Production Information<span class="pull-right"><a class="anchor hidden-xs" href="#Audio-Production-Information" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Audio-Production-Information" aria-hidden="true">TOC</a></span></h4> |
| <p>Audio Production Information is optional information describing the mixing |
| environment. Either none or both of the fields are written to the bitstream. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">-mixing_level <var class="var">number</var></samp></dt> |
| <dd><p>Mixing Level. Specifies peak sound pressure level (SPL) in the production |
| environment when the mix was mastered. Valid values are 80 to 111, or -1 for |
| unknown or not indicated. The default value is -1, but that value cannot be |
| used if the Audio Production Information is written to the bitstream. Therefore, |
| if the <code class="code">room_type</code> option is not the default value, the <code class="code">mixing_level</code> |
| option must not be -1. |
| </p> |
| </dd> |
| <dt><samp class="option">-room_type <var class="var">type</var></samp></dt> |
| <dd><p>Room Type. Describes the equalization used during the final mixing session at |
| the studio or on the dubbing stage. A large room is a dubbing stage with the |
| industry standard X-curve equalization; a small room has flat equalization. |
| This field will not be written to the bitstream if both the <code class="code">mixing_level</code> |
| option and the <code class="code">room_type</code> option have the default values. |
| </p><dl class="table"> |
| <dt><samp class="option">0</samp></dt> |
| <dt><samp class="option">notindicated</samp></dt> |
| <dd><p>Not Indicated (default) |
| </p></dd> |
| <dt><samp class="option">1</samp></dt> |
| <dt><samp class="option">large</samp></dt> |
| <dd><p>Large Room |
| </p></dd> |
| <dt><samp class="option">2</samp></dt> |
| <dt><samp class="option">small</samp></dt> |
| <dd><p>Small Room |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
| <a name="Other-Metadata-Options"></a> |
| <h4 class="subsubsection">8.2.1.4 Other Metadata Options<span class="pull-right"><a class="anchor hidden-xs" href="#Other-Metadata-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Other-Metadata-Options" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">-copyright <var class="var">boolean</var></samp></dt> |
| <dd><p>Copyright Indicator. Specifies whether a copyright exists for this audio. |
| </p><dl class="table"> |
| <dt><samp class="option">0</samp></dt> |
| <dt><samp class="option">off</samp></dt> |
| <dd><p>No Copyright Exists (default) |
| </p></dd> |
| <dt><samp class="option">1</samp></dt> |
| <dt><samp class="option">on</samp></dt> |
| <dd><p>Copyright Exists |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">-dialnorm <var class="var">value</var></samp></dt> |
| <dd><p>Dialogue Normalization. Indicates how far the average dialogue level of the |
| program is below digital 100% full scale (0 dBFS). This parameter determines a |
| level shift during audio reproduction that sets the average volume of the |
| dialogue to a preset level. The goal is to match volume level between program |
| sources. A value of -31dB will result in no volume level change, relative to |
| the source volume, during audio reproduction. Valid values are whole numbers in |
| the range -31 to -1, with -31 being the default. |
| </p> |
| </dd> |
| <dt><samp class="option">-dsur_mode <var class="var">mode</var></samp></dt> |
| <dd><p>Dolby Surround Mode. Specifies whether the stereo signal uses Dolby Surround |
| (Pro Logic). This field will only be written to the bitstream if the audio |
| stream is stereo. Using this option does <b class="b">NOT</b> mean the encoder will actually |
| apply Dolby Surround processing. |
| </p><dl class="table"> |
| <dt><samp class="option">0</samp></dt> |
| <dt><samp class="option">notindicated</samp></dt> |
| <dd><p>Not Indicated (default) |
| </p></dd> |
| <dt><samp class="option">1</samp></dt> |
| <dt><samp class="option">off</samp></dt> |
| <dd><p>Not Dolby Surround Encoded |
| </p></dd> |
| <dt><samp class="option">2</samp></dt> |
| <dt><samp class="option">on</samp></dt> |
| <dd><p>Dolby Surround Encoded |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">-original <var class="var">boolean</var></samp></dt> |
| <dd><p>Original Bit Stream Indicator. Specifies whether this audio is from the |
| original source and not a copy. |
| </p><dl class="table"> |
| <dt><samp class="option">0</samp></dt> |
| <dt><samp class="option">off</samp></dt> |
| <dd><p>Not Original Source |
| </p></dd> |
| <dt><samp class="option">1</samp></dt> |
| <dt><samp class="option">on</samp></dt> |
| <dd><p>Original Source (default) |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
| <a name="Extended-Bitstream-Information"></a> |
| <h4 class="subsection">8.2.2 Extended Bitstream Information<span class="pull-right"><a class="anchor hidden-xs" href="#Extended-Bitstream-Information" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Extended-Bitstream-Information" aria-hidden="true">TOC</a></span></h4> |
| <p>The extended bitstream options are part of the Alternate Bit Stream Syntax as |
| specified in Annex D of the A/52:2010 standard. It is grouped into 2 parts. |
| If any one parameter in a group is specified, all values in that group will be |
| written to the bitstream. Default values are used for those that are written |
| but have not been specified. If the mixing levels are written, the decoder |
| will use these values instead of the ones specified in the <code class="code">center_mixlev</code> |
| and <code class="code">surround_mixlev</code> options if it supports the Alternate Bit Stream |
| Syntax. |
| </p> |
| <a name="Extended-Bitstream-Information-_002d-Part-1"></a> |
| <h4 class="subsubsection">8.2.2.1 Extended Bitstream Information - Part 1<span class="pull-right"><a class="anchor hidden-xs" href="#Extended-Bitstream-Information-_002d-Part-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Extended-Bitstream-Information-_002d-Part-1" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">-dmix_mode <var class="var">mode</var></samp></dt> |
| <dd><p>Preferred Stereo Downmix Mode. Allows the user to select either Lt/Rt |
| (Dolby Surround) or Lo/Ro (normal stereo) as the preferred stereo downmix mode. |
| </p><dl class="table"> |
| <dt><samp class="option">0</samp></dt> |
| <dt><samp class="option">notindicated</samp></dt> |
| <dd><p>Not Indicated (default) |
| </p></dd> |
| <dt><samp class="option">1</samp></dt> |
| <dt><samp class="option">ltrt</samp></dt> |
| <dd><p>Lt/Rt Downmix Preferred |
| </p></dd> |
| <dt><samp class="option">2</samp></dt> |
| <dt><samp class="option">loro</samp></dt> |
| <dd><p>Lo/Ro Downmix Preferred |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">-ltrt_cmixlev <var class="var">level</var></samp></dt> |
| <dd><p>Lt/Rt Center Mix Level. The amount of gain the decoder should apply to the |
| center channel when downmixing to stereo in Lt/Rt mode. |
| </p><dl class="table"> |
| <dt><samp class="option">1.414</samp></dt> |
| <dd><p>Apply +3dB gain |
| </p></dd> |
| <dt><samp class="option">1.189</samp></dt> |
| <dd><p>Apply +1.5dB gain |
| </p></dd> |
| <dt><samp class="option">1.000</samp></dt> |
| <dd><p>Apply 0dB gain |
| </p></dd> |
| <dt><samp class="option">0.841</samp></dt> |
| <dd><p>Apply -1.5dB gain |
| </p></dd> |
| <dt><samp class="option">0.707</samp></dt> |
| <dd><p>Apply -3.0dB gain |
| </p></dd> |
| <dt><samp class="option">0.595</samp></dt> |
| <dd><p>Apply -4.5dB gain (default) |
| </p></dd> |
| <dt><samp class="option">0.500</samp></dt> |
| <dd><p>Apply -6.0dB gain |
| </p></dd> |
| <dt><samp class="option">0.000</samp></dt> |
| <dd><p>Silence Center Channel |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">-ltrt_surmixlev <var class="var">level</var></samp></dt> |
| <dd><p>Lt/Rt Surround Mix Level. The amount of gain the decoder should apply to the |
| surround channel(s) when downmixing to stereo in Lt/Rt mode. |
| </p><dl class="table"> |
| <dt><samp class="option">0.841</samp></dt> |
| <dd><p>Apply -1.5dB gain |
| </p></dd> |
| <dt><samp class="option">0.707</samp></dt> |
| <dd><p>Apply -3.0dB gain |
| </p></dd> |
| <dt><samp class="option">0.595</samp></dt> |
| <dd><p>Apply -4.5dB gain |
| </p></dd> |
| <dt><samp class="option">0.500</samp></dt> |
| <dd><p>Apply -6.0dB gain (default) |
| </p></dd> |
| <dt><samp class="option">0.000</samp></dt> |
| <dd><p>Silence Surround Channel(s) |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">-loro_cmixlev <var class="var">level</var></samp></dt> |
| <dd><p>Lo/Ro Center Mix Level. The amount of gain the decoder should apply to the |
| center channel when downmixing to stereo in Lo/Ro mode. |
| </p><dl class="table"> |
| <dt><samp class="option">1.414</samp></dt> |
| <dd><p>Apply +3dB gain |
| </p></dd> |
| <dt><samp class="option">1.189</samp></dt> |
| <dd><p>Apply +1.5dB gain |
| </p></dd> |
| <dt><samp class="option">1.000</samp></dt> |
| <dd><p>Apply 0dB gain |
| </p></dd> |
| <dt><samp class="option">0.841</samp></dt> |
| <dd><p>Apply -1.5dB gain |
| </p></dd> |
| <dt><samp class="option">0.707</samp></dt> |
| <dd><p>Apply -3.0dB gain |
| </p></dd> |
| <dt><samp class="option">0.595</samp></dt> |
| <dd><p>Apply -4.5dB gain (default) |
| </p></dd> |
| <dt><samp class="option">0.500</samp></dt> |
| <dd><p>Apply -6.0dB gain |
| </p></dd> |
| <dt><samp class="option">0.000</samp></dt> |
| <dd><p>Silence Center Channel |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">-loro_surmixlev <var class="var">level</var></samp></dt> |
| <dd><p>Lo/Ro Surround Mix Level. The amount of gain the decoder should apply to the |
| surround channel(s) when downmixing to stereo in Lo/Ro mode. |
| </p><dl class="table"> |
| <dt><samp class="option">0.841</samp></dt> |
| <dd><p>Apply -1.5dB gain |
| </p></dd> |
| <dt><samp class="option">0.707</samp></dt> |
| <dd><p>Apply -3.0dB gain |
| </p></dd> |
| <dt><samp class="option">0.595</samp></dt> |
| <dd><p>Apply -4.5dB gain |
| </p></dd> |
| <dt><samp class="option">0.500</samp></dt> |
| <dd><p>Apply -6.0dB gain (default) |
| </p></dd> |
| <dt><samp class="option">0.000</samp></dt> |
| <dd><p>Silence Surround Channel(s) |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
| <a name="Extended-Bitstream-Information-_002d-Part-2"></a> |
| <h4 class="subsubsection">8.2.2.2 Extended Bitstream Information - Part 2<span class="pull-right"><a class="anchor hidden-xs" href="#Extended-Bitstream-Information-_002d-Part-2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Extended-Bitstream-Information-_002d-Part-2" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">-dsurex_mode <var class="var">mode</var></samp></dt> |
| <dd><p>Dolby Surround EX Mode. Indicates whether the stream uses Dolby Surround EX |
| (7.1 matrixed to 5.1). Using this option does <b class="b">NOT</b> mean the encoder will actually |
| apply Dolby Surround EX processing. |
| </p><dl class="table"> |
| <dt><samp class="option">0</samp></dt> |
| <dt><samp class="option">notindicated</samp></dt> |
| <dd><p>Not Indicated (default) |
| </p></dd> |
| <dt><samp class="option">1</samp></dt> |
| <dt><samp class="option">on</samp></dt> |
| <dd><p>Dolby Surround EX Off |
| </p></dd> |
| <dt><samp class="option">2</samp></dt> |
| <dt><samp class="option">off</samp></dt> |
| <dd><p>Dolby Surround EX On |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">-dheadphone_mode <var class="var">mode</var></samp></dt> |
| <dd><p>Dolby Headphone Mode. Indicates whether the stream uses Dolby Headphone |
| encoding (multi-channel matrixed to 2.0 for use with headphones). Using this |
| option does <b class="b">NOT</b> mean the encoder will actually apply Dolby Headphone |
| processing. |
| </p><dl class="table"> |
| <dt><samp class="option">0</samp></dt> |
| <dt><samp class="option">notindicated</samp></dt> |
| <dd><p>Not Indicated (default) |
| </p></dd> |
| <dt><samp class="option">1</samp></dt> |
| <dt><samp class="option">on</samp></dt> |
| <dd><p>Dolby Headphone Off |
| </p></dd> |
| <dt><samp class="option">2</samp></dt> |
| <dt><samp class="option">off</samp></dt> |
| <dd><p>Dolby Headphone On |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">-ad_conv_type <var class="var">type</var></samp></dt> |
| <dd><p>A/D Converter Type. Indicates whether the audio has passed through HDCD A/D |
| conversion. |
| </p><dl class="table"> |
| <dt><samp class="option">0</samp></dt> |
| <dt><samp class="option">standard</samp></dt> |
| <dd><p>Standard A/D Converter (default) |
| </p></dd> |
| <dt><samp class="option">1</samp></dt> |
| <dt><samp class="option">hdcd</samp></dt> |
| <dd><p>HDCD A/D Converter |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
| <a name="Other-AC_002d3-Encoding-Options"></a> |
| <h4 class="subsection">8.2.3 Other AC-3 Encoding Options<span class="pull-right"><a class="anchor hidden-xs" href="#Other-AC_002d3-Encoding-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Other-AC_002d3-Encoding-Options" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">-stereo_rematrixing <var class="var">boolean</var></samp></dt> |
| <dd><p>Stereo Rematrixing. Enables/Disables use of rematrixing for stereo input. This |
| is an optional AC-3 feature that increases quality by selectively encoding |
| the left/right channels as mid/side. This option is enabled by default, and it |
| is highly recommended that it be left as enabled except for testing purposes. |
| </p> |
| </dd> |
| <dt><samp class="option">cutoff <var class="var">frequency</var></samp></dt> |
| <dd><p>Set lowpass cutoff frequency. If unspecified, the encoder selects a default |
| determined by various other encoding parameters. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="Floating_002dPoint_002dOnly-AC_002d3-Encoding-Options"></a> |
| <h4 class="subsection">8.2.4 Floating-Point-Only AC-3 Encoding Options<span class="pull-right"><a class="anchor hidden-xs" href="#Floating_002dPoint_002dOnly-AC_002d3-Encoding-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Floating_002dPoint_002dOnly-AC_002d3-Encoding-Options" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>These options are only valid for the floating-point encoder and do not exist |
| for the fixed-point encoder due to the corresponding features not being |
| implemented in fixed-point. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">-channel_coupling <var class="var">boolean</var></samp></dt> |
| <dd><p>Enables/Disables use of channel coupling, which is an optional AC-3 feature |
| that increases quality by combining high frequency information from multiple |
| channels into a single channel. The per-channel high frequency information is |
| sent with less accuracy in both the frequency and time domains. This allows |
| more bits to be used for lower frequencies while preserving enough information |
| to reconstruct the high frequencies. This option is enabled by default for the |
| floating-point encoder and should generally be left as enabled except for |
| testing purposes or to increase encoding speed. |
| </p><dl class="table"> |
| <dt><samp class="option">-1</samp></dt> |
| <dt><samp class="option">auto</samp></dt> |
| <dd><p>Selected by Encoder (default) |
| </p></dd> |
| <dt><samp class="option">0</samp></dt> |
| <dt><samp class="option">off</samp></dt> |
| <dd><p>Disable Channel Coupling |
| </p></dd> |
| <dt><samp class="option">1</samp></dt> |
| <dt><samp class="option">on</samp></dt> |
| <dd><p>Enable Channel Coupling |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">-cpl_start_band <var class="var">number</var></samp></dt> |
| <dd><p>Coupling Start Band. Sets the channel coupling start band, from 1 to 15. If a |
| value higher than the bandwidth is used, it will be reduced to 1 less than the |
| coupling end band. If <var class="var">auto</var> is used, the start band will be determined by |
| the encoder based on the bit rate, sample rate, and channel layout. This option |
| has no effect if channel coupling is disabled. |
| </p><dl class="table"> |
| <dt><samp class="option">-1</samp></dt> |
| <dt><samp class="option">auto</samp></dt> |
| <dd><p>Selected by Encoder (default) |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
| <a class="anchor" id="flac"></a><a name="flac-2"></a> |
| <h3 class="section">8.3 flac<span class="pull-right"><a class="anchor hidden-xs" href="#flac-2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-flac-2" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>FLAC (Free Lossless Audio Codec) Encoder |
| </p> |
| <a name="Options-12"></a> |
| <h4 class="subsection">8.3.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-12" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-12" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following options are supported by FFmpeg’s flac encoder. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">compression_level</samp></dt> |
| <dd><p>Sets the compression level, which chooses defaults for many other options |
| if they are not set explicitly. Valid values are from 0 to 12, 5 is the |
| default. |
| </p> |
| </dd> |
| <dt><samp class="option">frame_size</samp></dt> |
| <dd><p>Sets the size of the frames in samples per channel. |
| </p> |
| </dd> |
| <dt><samp class="option">lpc_coeff_precision</samp></dt> |
| <dd><p>Sets the LPC coefficient precision, valid values are from 1 to 15, 15 is the |
| default. |
| </p> |
| </dd> |
| <dt><samp class="option">lpc_type</samp></dt> |
| <dd><p>Sets the first stage LPC algorithm |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">none</samp>’</dt> |
| <dd><p>LPC is not used |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">fixed</samp>’</dt> |
| <dd><p>fixed LPC coefficients |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">levinson</samp>’</dt> |
| <dt>‘<samp class="samp">cholesky</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">lpc_passes</samp></dt> |
| <dd><p>Number of passes to use for Cholesky factorization during LPC analysis |
| </p> |
| </dd> |
| <dt><samp class="option">min_partition_order</samp></dt> |
| <dd><p>The minimum partition order |
| </p> |
| </dd> |
| <dt><samp class="option">max_partition_order</samp></dt> |
| <dd><p>The maximum partition order |
| </p> |
| </dd> |
| <dt><samp class="option">prediction_order_method</samp></dt> |
| <dd><dl class="table"> |
| <dt>‘<samp class="samp">estimation</samp>’</dt> |
| <dt>‘<samp class="samp">2level</samp>’</dt> |
| <dt>‘<samp class="samp">4level</samp>’</dt> |
| <dt>‘<samp class="samp">8level</samp>’</dt> |
| <dt>‘<samp class="samp">search</samp>’</dt> |
| <dd><p>Bruteforce search |
| </p></dd> |
| <dt>‘<samp class="samp">log</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">ch_mode</samp></dt> |
| <dd><p>Channel mode |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">auto</samp>’</dt> |
| <dd><p>The mode is chosen automatically for each frame |
| </p></dd> |
| <dt>‘<samp class="samp">indep</samp>’</dt> |
| <dd><p>Channels are independently coded |
| </p></dd> |
| <dt>‘<samp class="samp">left_side</samp>’</dt> |
| <dt>‘<samp class="samp">right_side</samp>’</dt> |
| <dt>‘<samp class="samp">mid_side</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">exact_rice_parameters</samp></dt> |
| <dd><p>Chooses if rice parameters are calculated exactly or approximately. |
| if set to 1 then they are chosen exactly, which slows the code down slightly and |
| improves compression slightly. |
| </p> |
| </dd> |
| <dt><samp class="option">multi_dim_quant</samp></dt> |
| <dd><p>Multi Dimensional Quantization. If set to 1 then a 2nd stage LPC algorithm is |
| applied after the first stage to finetune the coefficients. This is quite slow |
| and slightly improves compression. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a class="anchor" id="opusenc"></a><a name="opus"></a> |
| <h3 class="section">8.4 opus<span class="pull-right"><a class="anchor hidden-xs" href="#opus" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-opus" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Opus encoder. |
| </p> |
| <p>This is a native FFmpeg encoder for the Opus format. Currently, it’s in development and |
| only implements the CELT part of the codec. Its quality is usually worse and at best |
| is equal to the libopus encoder. |
| </p> |
| <a name="Options-13"></a> |
| <h4 class="subsection">8.4.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-13" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-13" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">b</samp></dt> |
| <dd><p>Set bit rate in bits/s. If unspecified it uses the number of channels and the layout |
| to make a good guess. |
| </p> |
| </dd> |
| <dt><samp class="option">opus_delay</samp></dt> |
| <dd><p>Sets the maximum delay in milliseconds. Lower delays than 20ms will very quickly |
| decrease quality. |
| </p></dd> |
| </dl> |
|
|
| <a class="anchor" id="libfdk_002daac_002denc"></a><a name="libfdk_005faac"></a> |
| <h3 class="section">8.5 libfdk_aac<span class="pull-right"><a class="anchor hidden-xs" href="#libfdk_005faac" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libfdk_005faac" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>libfdk-aac AAC (Advanced Audio Coding) encoder wrapper. |
| </p> |
| <p>The libfdk-aac library is based on the Fraunhofer FDK AAC code from |
| the Android project. |
| </p> |
| <p>Requires the presence of the libfdk-aac headers and library during |
| configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libfdk-aac</code>. The library is also incompatible with GPL, |
| so if you allow the use of GPL, you should configure with |
| <code class="code">--enable-gpl --enable-nonfree --enable-libfdk-aac</code>. |
| </p> |
| <p>This encoder has support for the AAC-HE profiles. |
| </p> |
| <p>VBR encoding, enabled through the <samp class="option">vbr</samp> or <samp class="option">flags |
| +qscale</samp> options, is experimental and only works with some |
| combinations of parameters. |
| </p> |
| <p>Support for encoding 7.1 audio is only available with libfdk-aac 0.1.3 or |
| higher. |
| </p> |
| <p>For more information see the fdk-aac project at |
| <a class="url" href="http://sourceforge.net/p/opencore-amr/fdk-aac/">http://sourceforge.net/p/opencore-amr/fdk-aac/</a>. |
| </p> |
| <a name="Options-14"></a> |
| <h4 class="subsection">8.5.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-14" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-14" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following options are mapped on the shared FFmpeg codec options. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">b</samp></dt> |
| <dd><p>Set bit rate in bits/s. If the bitrate is not explicitly specified, it |
| is automatically set to a suitable value depending on the selected |
| profile. |
| </p> |
| <p>In case VBR mode is enabled the option is ignored. |
| </p> |
| </dd> |
| <dt><samp class="option">ar</samp></dt> |
| <dd><p>Set audio sampling rate (in Hz). |
| </p> |
| </dd> |
| <dt><samp class="option">channels</samp></dt> |
| <dd><p>Set the number of audio channels. |
| </p> |
| </dd> |
| <dt><samp class="option">flags +qscale</samp></dt> |
| <dd><p>Enable fixed quality, VBR (Variable Bit Rate) mode. |
| Note that VBR is implicitly enabled when the <samp class="option">vbr</samp> value is |
| positive. |
| </p> |
| </dd> |
| <dt><samp class="option">cutoff</samp></dt> |
| <dd><p>Set cutoff frequency. If not specified (or explicitly set to 0) it |
| will use a value automatically computed by the library. Default value |
| is 0. |
| </p> |
| </dd> |
| <dt><samp class="option">profile</samp></dt> |
| <dd><p>Set audio profile. |
| </p> |
| <p>The following profiles are recognized: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">aac_low</samp>’</dt> |
| <dd><p>Low Complexity AAC (LC) |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">aac_he</samp>’</dt> |
| <dd><p>High Efficiency AAC (HE-AAC) |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">aac_he_v2</samp>’</dt> |
| <dd><p>High Efficiency AAC version 2 (HE-AACv2) |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">aac_ld</samp>’</dt> |
| <dd><p>Low Delay AAC (LD) |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">aac_eld</samp>’</dt> |
| <dd><p>Enhanced Low Delay AAC (ELD) |
| </p></dd> |
| </dl> |
|
|
| <p>If not specified it is set to ‘<samp class="samp">aac_low</samp>’. |
| </p></dd> |
| </dl> |
|
|
| <p>The following are private options of the libfdk_aac encoder. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">afterburner</samp></dt> |
| <dd><p>Enable afterburner feature if set to 1, disabled if set to 0. This |
| improves the quality but also the required processing power. |
| </p> |
| <p>Default value is 1. |
| </p> |
| </dd> |
| <dt><samp class="option">eld_sbr</samp></dt> |
| <dd><p>Enable SBR (Spectral Band Replication) for ELD if set to 1, disabled |
| if set to 0. |
| </p> |
| <p>Default value is 0. |
| </p> |
| </dd> |
| <dt><samp class="option">eld_v2</samp></dt> |
| <dd><p>Enable ELDv2 (LD-MPS extension for ELD stereo signals) for ELDv2 if set to 1, |
| disabled if set to 0. |
| </p> |
| <p>Note that option is available when fdk-aac version (AACENCODER_LIB_VL0.AACENCODER_LIB_VL1.AACENCODER_LIB_VL2) > (4.0.0). |
| </p> |
| <p>Default value is 0. |
| </p> |
| </dd> |
| <dt><samp class="option">signaling</samp></dt> |
| <dd><p>Set SBR/PS signaling style. |
| </p> |
| <p>It can assume one of the following values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">default</samp>’</dt> |
| <dd><p>choose signaling implicitly (explicit hierarchical by default, |
| implicit if global header is disabled) |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">implicit</samp>’</dt> |
| <dd><p>implicit backwards compatible signaling |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">explicit_sbr</samp>’</dt> |
| <dd><p>explicit SBR, implicit PS signaling |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">explicit_hierarchical</samp>’</dt> |
| <dd><p>explicit hierarchical signaling |
| </p></dd> |
| </dl> |
|
|
| <p>Default value is ‘<samp class="samp">default</samp>’. |
| </p> |
| </dd> |
| <dt><samp class="option">latm</samp></dt> |
| <dd><p>Output LATM/LOAS encapsulated data if set to 1, disabled if set to 0. |
| </p> |
| <p>Default value is 0. |
| </p> |
| </dd> |
| <dt><samp class="option">header_period</samp></dt> |
| <dd><p>Set StreamMuxConfig and PCE repetition period (in frames) for sending |
| in-band configuration buffers within LATM/LOAS transport layer. |
| </p> |
| <p>Must be a 16-bits non-negative integer. |
| </p> |
| <p>Default value is 0. |
| </p> |
| </dd> |
| <dt><samp class="option">vbr</samp></dt> |
| <dd><p>Set VBR mode, from 1 to 5. 1 is lowest quality (though still pretty |
| good) and 5 is highest quality. A value of 0 will disable VBR, and CBR |
| (Constant Bit Rate) is enabled. |
| </p> |
| <p>Currently only the ‘<samp class="samp">aac_low</samp>’ profile supports VBR encoding. |
| </p> |
| <p>VBR modes 1-5 correspond to roughly the following average bit rates: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">1</samp>’</dt> |
| <dd><p>32 kbps/channel |
| </p></dd> |
| <dt>‘<samp class="samp">2</samp>’</dt> |
| <dd><p>40 kbps/channel |
| </p></dd> |
| <dt>‘<samp class="samp">3</samp>’</dt> |
| <dd><p>48-56 kbps/channel |
| </p></dd> |
| <dt>‘<samp class="samp">4</samp>’</dt> |
| <dd><p>64 kbps/channel |
| </p></dd> |
| <dt>‘<samp class="samp">5</samp>’</dt> |
| <dd><p>about 80-96 kbps/channel |
| </p></dd> |
| </dl> |
|
|
| <p>Default value is 0. |
| </p> |
| </dd> |
| <dt><samp class="option">frame_length</samp></dt> |
| <dd><p>Set the audio frame length in samples. Default value is the internal |
| default of the library. Refer to the library’s documentation for information |
| about supported values. |
| </p></dd> |
| </dl> |
|
|
| <a name="Examples"></a> |
| <h4 class="subsection">8.5.2 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples" aria-hidden="true">TOC</a></span></h4> |
|
|
| <ul class="itemize mark-bullet"> |
| <li>Use <code class="command">ffmpeg</code> to convert an audio file to VBR AAC in an M4A (MP4) |
| container: |
| <div class="example"> |
| <pre class="example-preformatted">ffmpeg -i input.wav -codec:a libfdk_aac -vbr 3 output.m4a |
| </pre></div> |
|
|
| </li><li>Use <code class="command">ffmpeg</code> to convert an audio file to CBR 64k kbps AAC, using the |
| High-Efficiency AAC profile: |
| <div class="example"> |
| <pre class="example-preformatted">ffmpeg -i input.wav -c:a libfdk_aac -profile:a aac_he -b:a 64k output.m4a |
| </pre></div> |
| </li></ul> |
|
|
| <a class="anchor" id="liblc3_002denc"></a><a name="liblc3"></a> |
| <h3 class="section">8.6 liblc3<span class="pull-right"><a class="anchor hidden-xs" href="#liblc3" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-liblc3" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>liblc3 LC3 (Low Complexity Communication Codec) encoder wrapper. |
| </p> |
| <p>Requires the presence of the liblc3 headers and library during configuration. |
| You need to explicitly configure the build with <code class="code">--enable-liblc3</code>. |
| </p> |
| <p>This encoder has support for the Bluetooth SIG LC3 codec for the LE Audio |
| protocol, and the following features of LC3plus: |
| </p><ul class="itemize mark-bullet"> |
| <li>Frame duration of 2.5 and 5ms. |
| </li><li>High-Resolution mode, 48 KHz, and 96 kHz sampling rates. |
| </li></ul> |
|
|
| <p>For more information see the liblc3 project at |
| <a class="url" href="https://github.com/google/liblc3">https://github.com/google/liblc3</a>. |
| </p> |
| <a name="Options-15"></a> |
| <h4 class="subsection">8.6.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-15" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-15" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following options are mapped on the shared FFmpeg codec options. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">b <var class="var">bitrate</var></samp></dt> |
| <dd><p>Set the bit rate in bits/s. This will determine the fixed size of the encoded |
| frames, for a selected frame duration. |
| </p> |
| </dd> |
| <dt><samp class="option">ar <var class="var">frequency</var></samp></dt> |
| <dd><p>Set the audio sampling rate (in Hz). |
| </p> |
| </dd> |
| <dt><samp class="option">channels</samp></dt> |
| <dd><p>Set the number of audio channels. |
| </p> |
| </dd> |
| <dt><samp class="option">frame_duration</samp></dt> |
| <dd><p>Set the audio frame duration in milliseconds. Default value is 10ms. |
| Allowed frame durations are 2.5ms, 5ms, 7.5ms and 10ms. |
| LC3 (Bluetooth LE Audio), allows 7.5ms and 10ms; and LC3plus 2.5ms, 5ms |
| and 10ms. |
| </p> |
| <p>The 10ms frame duration is available in LC3 and LC3 plus standard. |
| In this mode, the produced bitstream can be referenced either as LC3 or LC3plus. |
| </p> |
| </dd> |
| <dt><samp class="option">high_resolution <var class="var">boolean</var></samp></dt> |
| <dd><p>Enable the high-resolution mode if set to 1. The high-resolution mode is |
| available with all LC3plus frame durations and for a sampling rate of 48 KHz, |
| and 96 KHz. |
| </p> |
| <p>The encoder automatically turns off this mode at lower sampling rates and |
| activates it at 96 KHz. |
| </p> |
| <p>This mode should be preferred at high bitrates. In this mode, the audio |
| bandwidth is always up to the Nyquist frequency, compared to LC3 at 48 KHz, |
| which limits the bandwidth to 20 KHz. |
| </p></dd> |
| </dl> |
|
|
| <a class="anchor" id="libmp3lame"></a><a name="libmp3lame-1"></a> |
| <h3 class="section">8.7 libmp3lame<span class="pull-right"><a class="anchor hidden-xs" href="#libmp3lame-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libmp3lame-1" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>LAME (Lame Ain’t an MP3 Encoder) MP3 encoder wrapper. |
| </p> |
| <p>Requires the presence of the libmp3lame headers and library during |
| configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libmp3lame</code>. |
| </p> |
| <p>See <a class="ref" href="#libshine">libshine</a> for a fixed-point MP3 encoder, although with a |
| lower quality. |
| </p> |
| <a name="Options-16"></a> |
| <h4 class="subsection">8.7.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-16" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-16" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following options are supported by the libmp3lame wrapper. The |
| <code class="command">lame</code>-equivalent of the options are listed in parentheses. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">b (<em class="emph">-b</em>)</samp></dt> |
| <dd><p>Set bitrate expressed in bits/s for CBR or ABR. LAME <code class="code">bitrate</code> is |
| expressed in kilobits/s. |
| </p> |
| </dd> |
| <dt><samp class="option">q (<em class="emph">-V</em>)</samp></dt> |
| <dd><p>Set constant quality setting for VBR. This option is valid only |
| using the <code class="command">ffmpeg</code> command-line tool. For library interface |
| users, use <samp class="option">global_quality</samp>. |
| </p> |
| </dd> |
| <dt><samp class="option">compression_level (<em class="emph">-q</em>)</samp></dt> |
| <dd><p>Set algorithm quality. Valid arguments are integers in the 0-9 range, |
| with 0 meaning highest quality but slowest, and 9 meaning fastest |
| while producing the worst quality. |
| </p> |
| </dd> |
| <dt><samp class="option">cutoff (<em class="emph">--lowpass</em>)</samp></dt> |
| <dd><p>Set lowpass cutoff frequency. If unspecified, the encoder dynamically |
| adjusts the cutoff. |
| </p> |
| </dd> |
| <dt><samp class="option">reservoir</samp></dt> |
| <dd><p>Enable use of bit reservoir when set to 1. Default value is 1. LAME |
| has this enabled by default, but can be overridden by use |
| <samp class="option">--nores</samp> option. |
| </p> |
| </dd> |
| <dt><samp class="option">joint_stereo (<em class="emph">-m j</em>)</samp></dt> |
| <dd><p>Enable the encoder to use (on a frame by frame basis) either L/R |
| stereo or mid/side stereo. Default value is 1. |
| </p> |
| </dd> |
| <dt><samp class="option">abr (<em class="emph">--abr</em>)</samp></dt> |
| <dd><p>Enable the encoder to use ABR when set to 1. The <code class="command">lame</code> |
| <samp class="option">--abr</samp> sets the target bitrate, while this options only |
| tells FFmpeg to use ABR still relies on <samp class="option">b</samp> to set bitrate. |
| </p> |
| </dd> |
| <dt><samp class="option">copyright (<em class="emph">-c</em>)</samp></dt> |
| <dd><p>Set MPEG audio copyright flag when set to 1. The default value is 0 |
| (disabled). |
| </p> |
| </dd> |
| <dt><samp class="option">original (<em class="emph">-o</em>)</samp></dt> |
| <dd><p>Set MPEG audio original flag when set to 1. The default value is 1 |
| (enabled). |
| </p></dd> |
| </dl> |
|
|
| <a name="libopencore_002damrnb-1"></a> |
| <h3 class="section">8.8 libopencore-amrnb<span class="pull-right"><a class="anchor hidden-xs" href="#libopencore_002damrnb-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libopencore_002damrnb-1" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>OpenCORE Adaptive Multi-Rate Narrowband encoder. |
| </p> |
| <p>Requires the presence of the libopencore-amrnb headers and library during |
| configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libopencore-amrnb --enable-version3</code>. |
| </p> |
| <p>This is a mono-only encoder. Officially it only supports 8000Hz sample rate, |
| but you can override it by setting <samp class="option">strict</samp> to ‘<samp class="samp">unofficial</samp>’ or |
| lower. |
| </p> |
| <a name="Options-17"></a> |
| <h4 class="subsection">8.8.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-17" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-17" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">b</samp></dt> |
| <dd><p>Set bitrate in bits per second. Only the following bitrates are supported, |
| otherwise libavcodec will round to the nearest valid bitrate. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">4750</samp></dt> |
| <dt><samp class="option">5150</samp></dt> |
| <dt><samp class="option">5900</samp></dt> |
| <dt><samp class="option">6700</samp></dt> |
| <dt><samp class="option">7400</samp></dt> |
| <dt><samp class="option">7950</samp></dt> |
| <dt><samp class="option">10200</samp></dt> |
| <dt><samp class="option">12200</samp></dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">dtx</samp></dt> |
| <dd><p>Allow discontinuous transmission (generate comfort noise) when set to 1. The |
| default value is 0 (disabled). |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="libopus-1"></a> |
| <h3 class="section">8.9 libopus<span class="pull-right"><a class="anchor hidden-xs" href="#libopus-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libopus-1" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>libopus Opus Interactive Audio Codec encoder wrapper. |
| </p> |
| <p>Requires the presence of the libopus headers and library during |
| configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libopus</code>. |
| </p> |
| <a name="Option-Mapping"></a> |
| <h4 class="subsection">8.9.1 Option Mapping<span class="pull-right"><a class="anchor hidden-xs" href="#Option-Mapping" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Option-Mapping" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>Most libopus options are modelled after the <code class="command">opusenc</code> utility from |
| opus-tools. The following is an option mapping chart describing options |
| supported by the libopus wrapper, and their <code class="command">opusenc</code>-equivalent |
| in parentheses. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">b (<em class="emph">bitrate</em>)</samp></dt> |
| <dd><p>Set the bit rate in bits/s. FFmpeg’s <samp class="option">b</samp> option is |
| expressed in bits/s, while <code class="command">opusenc</code>’s <samp class="option">bitrate</samp> in |
| kilobits/s. |
| </p> |
| </dd> |
| <dt><samp class="option">vbr (<em class="emph">vbr</em>, <em class="emph">hard-cbr</em>, and <em class="emph">cvbr</em>)</samp></dt> |
| <dd><p>Set VBR mode. The FFmpeg <samp class="option">vbr</samp> option has the following |
| valid arguments, with the <code class="command">opusenc</code> equivalent options |
| in parentheses: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">off (<em class="emph">hard-cbr</em>)</samp>’</dt> |
| <dd><p>Use constant bit rate encoding. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">on (<em class="emph">vbr</em>)</samp>’</dt> |
| <dd><p>Use variable bit rate encoding (the default). |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">constrained (<em class="emph">cvbr</em>)</samp>’</dt> |
| <dd><p>Use constrained variable bit rate encoding. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">compression_level (<em class="emph">comp</em>)</samp></dt> |
| <dd><p>Set encoding algorithm complexity. Valid options are integers in |
| the 0-10 range. 0 gives the fastest encodes but lower quality, while 10 |
| gives the highest quality but slowest encoding. The default is 10. |
| </p> |
| </dd> |
| <dt><samp class="option">frame_duration (<em class="emph">framesize</em>)</samp></dt> |
| <dd><p>Set maximum frame size, or duration of a frame in milliseconds. The |
| argument must be exactly the following: 2.5, 5, 10, 20, 40, 60. Smaller |
| frame sizes achieve lower latency but less quality at a given bitrate. |
| Sizes greater than 20ms are only interesting at fairly low bitrates. |
| The default is 20ms. |
| </p> |
| </dd> |
| <dt><samp class="option">packet_loss (<em class="emph">expect-loss</em>)</samp></dt> |
| <dd><p>Set expected packet loss percentage. The default is 0. |
| </p> |
| </dd> |
| <dt><samp class="option">fec (<em class="emph">n/a</em>)</samp></dt> |
| <dd><p>Enable inband forward error correction. <samp class="option">packet_loss</samp> must be non-zero |
| to take advantage - frequency of FEC ’side-data’ is proportional to expected packet loss. |
| Default is disabled. |
| </p> |
| </dd> |
| <dt><samp class="option">application (N.A.)</samp></dt> |
| <dd><p>Set intended application type. Valid options are listed below: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">voip</samp>’</dt> |
| <dd><p>Favor improved speech intelligibility. |
| </p></dd> |
| <dt>‘<samp class="samp">audio</samp>’</dt> |
| <dd><p>Favor faithfulness to the input (the default). |
| </p></dd> |
| <dt>‘<samp class="samp">lowdelay</samp>’</dt> |
| <dd><p>Restrict to only the lowest delay modes by disabling voice-optimized |
| modes. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">cutoff (N.A.)</samp></dt> |
| <dd><p>Set cutoff bandwidth in Hz. The argument must be exactly one of the |
| following: 4000, 6000, 8000, 12000, or 20000, corresponding to |
| narrowband, mediumband, wideband, super wideband, and fullband |
| respectively. The default is 0 (cutoff disabled). Note that libopus |
| forces a wideband cutoff for bitrates < 15 kbps, unless CELT-only |
| (<samp class="option">application</samp> set to ‘<samp class="samp">lowdelay</samp>’) mode is used. |
| </p> |
| </dd> |
| <dt><samp class="option">mapping_family (<em class="emph">mapping_family</em>)</samp></dt> |
| <dd><p>Set channel mapping family to be used by the encoder. The default value of -1 |
| uses mapping family 0 for mono and stereo inputs, and mapping family 1 |
| otherwise. The default also disables the surround masking and LFE bandwidth |
| optimizations in libopus, and requires that the input contains 8 channels or |
| fewer. |
| </p> |
| <p>Other values include 0 for mono and stereo, 1 for surround sound with masking |
| and LFE bandwidth optimizations, and 255 for independent streams with an |
| unspecified channel layout. |
| </p> |
| </dd> |
| <dt><samp class="option">dtx (N.A.)</samp></dt> |
| <dd><p>Allow discontinuous transmission when set to 1. The default value is 0 |
| (disabled). |
| </p> |
| </dd> |
| <dt><samp class="option">apply_phase_inv (N.A.) (requires libopus >= 1.2)</samp></dt> |
| <dd><p>If set to 0, disables the use of phase inversion for intensity stereo, |
| improving the quality of mono downmixes, but slightly reducing normal stereo |
| quality. The default is 1 (phase inversion enabled). |
| </p> |
| </dd> |
| </dl> |
|
|
| <a class="anchor" id="libshine"></a><a name="libshine-1"></a> |
| <h3 class="section">8.10 libshine<span class="pull-right"><a class="anchor hidden-xs" href="#libshine-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libshine-1" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Shine Fixed-Point MP3 encoder wrapper. |
| </p> |
| <p>Shine is a fixed-point MP3 encoder. It has a far better performance on |
| platforms without an FPU, e.g. armel CPUs, and some phones and tablets. |
| However, as it is more targeted on performance than quality, it is not on par |
| with LAME and other production-grade encoders quality-wise. Also, according to |
| the project’s homepage, this encoder may not be free of bugs as the code was |
| written a long time ago and the project was dead for at least 5 years. |
| </p> |
| <p>This encoder only supports stereo and mono input. This is also CBR-only. |
| </p> |
| <p>The original project (last updated in early 2007) is at |
| <a class="url" href="http://sourceforge.net/projects/libshine-fxp/">http://sourceforge.net/projects/libshine-fxp/</a>. We only support the |
| updated fork by the Savonet/Liquidsoap project at <a class="url" href="https://github.com/savonet/shine">https://github.com/savonet/shine</a>. |
| </p> |
| <p>Requires the presence of the libshine headers and library during |
| configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libshine</code>. |
| </p> |
| <p>See also <a class="ref" href="#libmp3lame">libmp3lame</a>. |
| </p> |
| <a name="Options-18"></a> |
| <h4 class="subsection">8.10.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-18" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-18" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following options are supported by the libshine wrapper. The |
| <code class="command">shineenc</code>-equivalent of the options are listed in parentheses. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">b (<em class="emph">-b</em>)</samp></dt> |
| <dd><p>Set bitrate expressed in bits/s for CBR. <code class="command">shineenc</code> <samp class="option">-b</samp> option |
| is expressed in kilobits/s. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="libtwolame"></a> |
| <h3 class="section">8.11 libtwolame<span class="pull-right"><a class="anchor hidden-xs" href="#libtwolame" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libtwolame" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>TwoLAME MP2 encoder wrapper. |
| </p> |
| <p>Requires the presence of the libtwolame headers and library during |
| configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libtwolame</code>. |
| </p> |
| <a name="Options-19"></a> |
| <h4 class="subsection">8.11.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-19" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-19" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following options are supported by the libtwolame wrapper. The |
| <code class="command">twolame</code>-equivalent options follow the FFmpeg ones and are in |
| parentheses. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">b (<em class="emph">-b</em>)</samp></dt> |
| <dd><p>Set bitrate expressed in bits/s for CBR. <code class="command">twolame</code> <samp class="option">b</samp> |
| option is expressed in kilobits/s. Default value is 128k. |
| </p> |
| </dd> |
| <dt><samp class="option">q (<em class="emph">-V</em>)</samp></dt> |
| <dd><p>Set quality for experimental VBR support. Maximum value range is |
| from -50 to 50, useful range is from -10 to 10. The higher the |
| value, the better the quality. This option is valid only using the |
| <code class="command">ffmpeg</code> command-line tool. For library interface users, |
| use <samp class="option">global_quality</samp>. |
| </p> |
| </dd> |
| <dt><samp class="option">mode (<em class="emph">--mode</em>)</samp></dt> |
| <dd><p>Set the mode of the resulting audio. Possible values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">auto</samp>’</dt> |
| <dd><p>Choose mode automatically based on the input. This is the default. |
| </p></dd> |
| <dt>‘<samp class="samp">stereo</samp>’</dt> |
| <dd><p>Stereo |
| </p></dd> |
| <dt>‘<samp class="samp">joint_stereo</samp>’</dt> |
| <dd><p>Joint stereo |
| </p></dd> |
| <dt>‘<samp class="samp">dual_channel</samp>’</dt> |
| <dd><p>Dual channel |
| </p></dd> |
| <dt>‘<samp class="samp">mono</samp>’</dt> |
| <dd><p>Mono |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">psymodel (<em class="emph">--psyc-mode</em>)</samp></dt> |
| <dd><p>Set psychoacoustic model to use in encoding. The argument must be |
| an integer between -1 and 4, inclusive. The higher the value, the |
| better the quality. The default value is 3. |
| </p> |
| </dd> |
| <dt><samp class="option">energy_levels (<em class="emph">--energy</em>)</samp></dt> |
| <dd><p>Enable energy levels extensions when set to 1. The default value is |
| 0 (disabled). |
| </p> |
| </dd> |
| <dt><samp class="option">error_protection (<em class="emph">--protect</em>)</samp></dt> |
| <dd><p>Enable CRC error protection when set to 1. The default value is 0 |
| (disabled). |
| </p> |
| </dd> |
| <dt><samp class="option">copyright (<em class="emph">--copyright</em>)</samp></dt> |
| <dd><p>Set MPEG audio copyright flag when set to 1. The default value is 0 |
| (disabled). |
| </p> |
| </dd> |
| <dt><samp class="option">original (<em class="emph">--original</em>)</samp></dt> |
| <dd><p>Set MPEG audio original flag when set to 1. The default value is 0 |
| (disabled). |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="libvo_002damrwbenc"></a> |
| <h3 class="section">8.12 libvo-amrwbenc<span class="pull-right"><a class="anchor hidden-xs" href="#libvo_002damrwbenc" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libvo_002damrwbenc" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>VisualOn Adaptive Multi-Rate Wideband encoder. |
| </p> |
| <p>Requires the presence of the libvo-amrwbenc headers and library during |
| configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libvo-amrwbenc --enable-version3</code>. |
| </p> |
| <p>This is a mono-only encoder. Officially it only supports 16000Hz sample |
| rate, but you can override it by setting <samp class="option">strict</samp> to |
| ‘<samp class="samp">unofficial</samp>’ or lower. |
| </p> |
| <a name="Options-20"></a> |
| <h4 class="subsection">8.12.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-20" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-20" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">b</samp></dt> |
| <dd><p>Set bitrate in bits/s. Only the following bitrates are supported, otherwise |
| libavcodec will round to the nearest valid bitrate. |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">6600</samp>’</dt> |
| <dt>‘<samp class="samp">8850</samp>’</dt> |
| <dt>‘<samp class="samp">12650</samp>’</dt> |
| <dt>‘<samp class="samp">14250</samp>’</dt> |
| <dt>‘<samp class="samp">15850</samp>’</dt> |
| <dt>‘<samp class="samp">18250</samp>’</dt> |
| <dt>‘<samp class="samp">19850</samp>’</dt> |
| <dt>‘<samp class="samp">23050</samp>’</dt> |
| <dt>‘<samp class="samp">23850</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">dtx</samp></dt> |
| <dd><p>Allow discontinuous transmission (generate comfort noise) when set to 1. The |
| default value is 0 (disabled). |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="libvorbis"></a> |
| <h3 class="section">8.13 libvorbis<span class="pull-right"><a class="anchor hidden-xs" href="#libvorbis" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libvorbis" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>libvorbis encoder wrapper. |
| </p> |
| <p>Requires the presence of the libvorbisenc headers and library during |
| configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libvorbis</code>. |
| </p> |
| <a name="Options-21"></a> |
| <h4 class="subsection">8.13.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-21" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-21" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following options are supported by the libvorbis wrapper. The |
| <code class="command">oggenc</code>-equivalent of the options are listed in parentheses. |
| </p> |
| <p>To get a more accurate and extensive documentation of the libvorbis |
| options, consult the libvorbisenc’s and <code class="command">oggenc</code>’s documentations. |
| See <a class="url" href="http://xiph.org/vorbis/">http://xiph.org/vorbis/</a>, |
| <a class="url" href="http://wiki.xiph.org/Vorbis-tools">http://wiki.xiph.org/Vorbis-tools</a>, and oggenc(1). |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">b (<em class="emph">-b</em>)</samp></dt> |
| <dd><p>Set bitrate expressed in bits/s for ABR. <code class="command">oggenc</code> <samp class="option">-b</samp> is |
| expressed in kilobits/s. |
| </p> |
| </dd> |
| <dt><samp class="option">q (<em class="emph">-q</em>)</samp></dt> |
| <dd><p>Set constant quality setting for VBR. The value should be a float |
| number in the range of -1.0 to 10.0. The higher the value, the better |
| the quality. The default value is ‘<samp class="samp">3.0</samp>’. |
| </p> |
| <p>This option is valid only using the <code class="command">ffmpeg</code> command-line tool. |
| For library interface users, use <samp class="option">global_quality</samp>. |
| </p> |
| </dd> |
| <dt><samp class="option">cutoff (<em class="emph">--advanced-encode-option lowpass_frequency=N</em>)</samp></dt> |
| <dd><p>Set cutoff bandwidth in Hz, a value of 0 disables cutoff. <code class="command">oggenc</code>’s |
| related option is expressed in kHz. The default value is ‘<samp class="samp">0</samp>’ (cutoff |
| disabled). |
| </p> |
| </dd> |
| <dt><samp class="option">minrate (<em class="emph">-m</em>)</samp></dt> |
| <dd><p>Set minimum bitrate expressed in bits/s. <code class="command">oggenc</code> <samp class="option">-m</samp> is |
| expressed in kilobits/s. |
| </p> |
| </dd> |
| <dt><samp class="option">maxrate (<em class="emph">-M</em>)</samp></dt> |
| <dd><p>Set maximum bitrate expressed in bits/s. <code class="command">oggenc</code> <samp class="option">-M</samp> is |
| expressed in kilobits/s. This only has effect on ABR mode. |
| </p> |
| </dd> |
| <dt><samp class="option">iblock (<em class="emph">--advanced-encode-option impulse_noisetune=N</em>)</samp></dt> |
| <dd><p>Set noise floor bias for impulse blocks. The value is a float number from |
| -15.0 to 0.0. A negative bias instructs the encoder to pay special attention |
| to the crispness of transients in the encoded audio. The tradeoff for better |
| transient response is a higher bitrate. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a class="anchor" id="mjpegenc"></a><a name="mjpeg"></a> |
| <h3 class="section">8.14 mjpeg<span class="pull-right"><a class="anchor hidden-xs" href="#mjpeg" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-mjpeg" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Motion JPEG encoder. |
| </p> |
| <a name="Options-22"></a> |
| <h4 class="subsection">8.14.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-22" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-22" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">huffman</samp></dt> |
| <dd><p>Set the huffman encoding strategy. Possible values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">default</samp>’</dt> |
| <dd><p>Use the default huffman tables. This is the default strategy. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">optimal</samp>’</dt> |
| <dd><p>Compute and use optimal huffman tables. |
| </p> |
| </dd> |
| </dl> |
| </dd> |
| </dl> |
|
|
| <a class="anchor" id="wavpackenc"></a><a name="wavpack"></a> |
| <h3 class="section">8.15 wavpack<span class="pull-right"><a class="anchor hidden-xs" href="#wavpack" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-wavpack" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>WavPack lossless audio encoder. |
| </p> |
| <a name="Options-23"></a> |
| <h4 class="subsection">8.15.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-23" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-23" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The equivalent options for <code class="command">wavpack</code> command line utility are listed in |
| parentheses. |
| </p> |
| <a name="Shared-options"></a> |
| <h4 class="subsubsection">8.15.1.1 Shared options<span class="pull-right"><a class="anchor hidden-xs" href="#Shared-options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Shared-options" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following shared options are effective for this encoder. Only special notes |
| about this particular encoder will be documented here. For the general meaning |
| of the options, see <a class="ref" href="#codec_002doptions">the Codec Options chapter</a>. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">frame_size (<em class="emph">--blocksize</em>)</samp></dt> |
| <dd><p>For this encoder, the range for this option is between 128 and 131072. Default |
| is automatically decided based on sample rate and number of channel. |
| </p> |
| <p>For the complete formula of calculating default, see |
| <samp class="file">libavcodec/wavpackenc.c</samp>. |
| </p> |
| </dd> |
| <dt><samp class="option">compression_level (<em class="emph">-f</em>, <em class="emph">-h</em>, <em class="emph">-hh</em>, and <em class="emph">-x</em>)</samp></dt> |
| </dl> |
|
|
| <a name="Private-options"></a> |
| <h4 class="subsubsection">8.15.1.2 Private options<span class="pull-right"><a class="anchor hidden-xs" href="#Private-options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Private-options" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">joint_stereo (<em class="emph">-j</em>)</samp></dt> |
| <dd><p>Set whether to enable joint stereo. Valid values are: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">on (<em class="emph">1</em>)</samp>’</dt> |
| <dd><p>Force mid/side audio encoding. |
| </p></dd> |
| <dt>‘<samp class="samp">off (<em class="emph">0</em>)</samp>’</dt> |
| <dd><p>Force left/right audio encoding. |
| </p></dd> |
| <dt>‘<samp class="samp">auto</samp>’</dt> |
| <dd><p>Let the encoder decide automatically. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">optimize_mono</samp></dt> |
| <dd><p>Set whether to enable optimization for mono. This option is only effective for |
| non-mono streams. Available values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">on</samp>’</dt> |
| <dd><p>enabled |
| </p></dd> |
| <dt>‘<samp class="samp">off</samp>’</dt> |
| <dd><p>disabled |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
|
|
| <a name="Video-Encoders"></a> |
| <h2 class="chapter">9 Video Encoders<span class="pull-right"><a class="anchor hidden-xs" href="#Video-Encoders" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Video-Encoders" aria-hidden="true">TOC</a></span></h2> |
|
|
| <p>A description of some of the currently available video encoders |
| follows. |
| </p> |
| <a name="a64_005fmulti_002c-a64_005fmulti5"></a> |
| <h3 class="section">9.1 a64_multi, a64_multi5<span class="pull-right"><a class="anchor hidden-xs" href="#a64_005fmulti_002c-a64_005fmulti5" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-a64_005fmulti_002c-a64_005fmulti5" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>A64 / Commodore 64 multicolor charset encoder. <code class="code">a64_multi5</code> is extended with 5th color (colram). |
| </p> |
| <a name="Cinepak"></a> |
| <h3 class="section">9.2 Cinepak<span class="pull-right"><a class="anchor hidden-xs" href="#Cinepak" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Cinepak" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Cinepak aka CVID encoder. |
| Compatible with Windows 3.1 and vintage MacOS. |
| </p> |
| <a name="Options-24"></a> |
| <h4 class="subsection">9.2.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-24" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-24" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">g <var class="var">integer</var></samp></dt> |
| <dd><p>Keyframe interval. |
| A keyframe is inserted at least every <code class="code">-g</code> frames, sometimes sooner. |
| </p> |
| </dd> |
| <dt><samp class="option">q:v <var class="var">integer</var></samp></dt> |
| <dd><p>Quality factor. Lower is better. Higher gives lower bitrate. |
| The following table lists bitrates when encoding akiyo_cif.y4m for various values of <code class="code">-q:v</code> with <code class="code">-g 100</code>: |
| </p> |
| <dl class="table"> |
| <dt><samp class="option"><code class="code">-q:v 1</code> 1918 kb/s</samp></dt> |
| <dt><samp class="option"><code class="code">-q:v 2</code> 1735 kb/s</samp></dt> |
| <dt><samp class="option"><code class="code">-q:v 4</code> 1500 kb/s</samp></dt> |
| <dt><samp class="option"><code class="code">-q:v 10</code> 1041 kb/s</samp></dt> |
| <dt><samp class="option"><code class="code">-q:v 20</code> 826 kb/s</samp></dt> |
| <dt><samp class="option"><code class="code">-q:v 40</code> 553 kb/s</samp></dt> |
| <dt><samp class="option"><code class="code">-q:v 100</code> 394 kb/s</samp></dt> |
| <dt><samp class="option"><code class="code">-q:v 200</code> 312 kb/s</samp></dt> |
| <dt><samp class="option"><code class="code">-q:v 400</code> 266 kb/s</samp></dt> |
| <dt><samp class="option"><code class="code">-q:v 1000</code> 237 kb/s</samp></dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">max_extra_cb_iterations <var class="var">integer</var></samp></dt> |
| <dd><p>Max extra codebook recalculation passes, more is better and slower. |
| </p> |
| </dd> |
| <dt><samp class="option">skip_empty_cb <var class="var">boolean</var></samp></dt> |
| <dd><p>Avoid wasting bytes, ignore vintage MacOS decoder. |
| </p> |
| </dd> |
| <dt><samp class="option">max_strips <var class="var">integer</var></samp></dt> |
| <dt><samp class="option">min_strips <var class="var">integer</var></samp></dt> |
| <dd><p>The minimum and maximum number of strips to use. |
| Wider range sometimes improves quality. |
| More strips is generally better quality but costs more bits. |
| Fewer strips tend to yield more keyframes. |
| Vintage compatible is 1..3. |
| </p> |
| </dd> |
| <dt><samp class="option">strip_number_adaptivity <var class="var">integer</var></samp></dt> |
| <dd><p>How much number of strips is allowed to change between frames. |
| Higher is better but slower. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a class="anchor" id="ffv1"></a><a name="ffv1-1"></a> |
| <h3 class="section">9.3 ffv1<span class="pull-right"><a class="anchor hidden-xs" href="#ffv1-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-ffv1-1" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>FFv1 Encoder |
| </p> |
| <a name="Options-25"></a> |
| <h4 class="subsection">9.3.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-25" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-25" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following options are supported by FFmpeg’s FFv1 encoder. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">context</samp></dt> |
| <dd><p>Sets the context size, 0 (default) is small, 1 is big. |
| </p> |
| </dd> |
| <dt><samp class="option">coder</samp></dt> |
| <dd><p>Set the coder, |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">rice</samp>’</dt> |
| <dd><p>Golomb rice coder |
| </p></dd> |
| <dt>‘<samp class="samp">range_def</samp>’</dt> |
| <dd><p>Range coder with default table |
| </p></dd> |
| <dt>‘<samp class="samp">range_tab</samp>’</dt> |
| <dd><p>Range coder with custom table |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">slicecrc</samp></dt> |
| <dd><p>-1 (default, automatic), 1 use crc with zero initial and final state, 2 use crc with non zero initial and final state |
| </p> |
| </dd> |
| <dt><samp class="option">qtable</samp></dt> |
| <dd><dl class="table"> |
| <dt>‘<samp class="samp">default</samp>’</dt> |
| <dd><p>default, automatic |
| </p></dd> |
| <dt>‘<samp class="samp">8bit</samp>’</dt> |
| <dd><p>use 8bit default |
| </p></dd> |
| <dt>‘<samp class="samp">greater8bit</samp>’</dt> |
| <dd><p>use >8bit default |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">remap_optimizer</samp></dt> |
| <dd><p>0 - 5, default 3, how much effort the encoder puts into optimizing the remap table. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="GIF"></a> |
| <h3 class="section">9.4 GIF<span class="pull-right"><a class="anchor hidden-xs" href="#GIF" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-GIF" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>GIF image/animation encoder. |
| </p> |
| <a name="Options-26"></a> |
| <h4 class="subsection">9.4.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-26" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-26" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">gifflags <var class="var">integer</var></samp></dt> |
| <dd><p>Sets the flags used for GIF encoding. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">offsetting</samp></dt> |
| <dd><p>Enables picture offsetting. |
| </p> |
| <p>Default is enabled. |
| </p> |
| </dd> |
| <dt><samp class="option">transdiff</samp></dt> |
| <dd><p>Enables transparency detection between frames. |
| </p> |
| <p>Default is enabled. |
| </p> |
| </dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">gifimage <var class="var">integer</var></samp></dt> |
| <dd><p>Enables encoding one full GIF image per frame, rather than an animated GIF. |
| </p> |
| <p>Default value is <samp class="option">0</samp>. |
| </p> |
| </dd> |
| <dt><samp class="option">global_palette <var class="var">integer</var></samp></dt> |
| <dd><p>Writes a palette to the global GIF header where feasible. |
| </p> |
| <p>If disabled, every frame will always have a palette written, even if there |
| is a global palette supplied. |
| </p> |
| <p>Default value is <samp class="option">1</samp>. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="Hap"></a> |
| <h3 class="section">9.5 Hap<span class="pull-right"><a class="anchor hidden-xs" href="#Hap" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Hap" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Vidvox Hap video encoder. |
| </p> |
| <a name="Options-27"></a> |
| <h4 class="subsection">9.5.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-27" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-27" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">format <var class="var">integer</var></samp></dt> |
| <dd><p>Specifies the Hap format to encode. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">hap</samp></dt> |
| <dt><samp class="option">hap_alpha</samp></dt> |
| <dt><samp class="option">hap_q</samp></dt> |
| </dl> |
|
|
| <p>Default value is <samp class="option">hap</samp>. |
| </p> |
| </dd> |
| <dt><samp class="option">chunks <var class="var">integer</var></samp></dt> |
| <dd><p>Specifies the number of chunks to split frames into, between 1 and 64. This |
| permits multithreaded decoding of large frames, potentially at the cost of |
| data-rate. The encoder may modify this value to divide frames evenly. |
| </p> |
| <p>Default value is <var class="var">1</var>. |
| </p> |
| </dd> |
| <dt><samp class="option">compressor <var class="var">integer</var></samp></dt> |
| <dd><p>Specifies the second-stage compressor to use. If set to <samp class="option">none</samp>, |
| <samp class="option">chunks</samp> will be limited to 1, as chunked uncompressed frames offer no |
| benefit. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">none</samp></dt> |
| <dt><samp class="option">snappy</samp></dt> |
| </dl> |
|
|
| <p>Default value is <samp class="option">snappy</samp>. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="jpeg2000"></a> |
| <h3 class="section">9.6 jpeg2000<span class="pull-right"><a class="anchor hidden-xs" href="#jpeg2000" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-jpeg2000" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>The native jpeg 2000 encoder is lossy by default, the <code class="code">-q:v</code> |
| option can be used to set the encoding quality. Lossless encoding |
| can be selected with <code class="code">-pred 1</code>. |
| </p> |
| <a name="Options-28"></a> |
| <h4 class="subsection">9.6.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-28" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-28" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">format <var class="var">integer</var></samp></dt> |
| <dd><p>Can be set to either <code class="code">j2k</code> or <code class="code">jp2</code> (the default) that |
| makes it possible to store non-rgb pix_fmts. |
| </p> |
| </dd> |
| <dt><samp class="option">tile_width <var class="var">integer</var></samp></dt> |
| <dd><p>Sets tile width. Range is 1 to 1073741824. Default is 256. |
| </p> |
| </dd> |
| <dt><samp class="option">tile_height <var class="var">integer</var></samp></dt> |
| <dd><p>Sets tile height. Range is 1 to 1073741824. Default is 256. |
| </p> |
| </dd> |
| <dt><samp class="option">pred <var class="var">integer</var></samp></dt> |
| <dd><p>Allows setting the discrete wavelet transform (DWT) type |
| </p><dl class="table"> |
| <dt><samp class="option">dwt97int (Lossy)</samp></dt> |
| <dt><samp class="option">dwt53 (Lossless)</samp></dt> |
| </dl> |
| <p>Default is <code class="code">dwt97int</code> |
| </p> |
| </dd> |
| <dt><samp class="option">sop <var class="var">boolean</var></samp></dt> |
| <dd><p>Enable this to add SOP marker at the start of each packet. Disabled by default. |
| </p> |
| </dd> |
| <dt><samp class="option">eph <var class="var">boolean</var></samp></dt> |
| <dd><p>Enable this to add EPH marker at the end of each packet header. Disabled by default. |
| </p> |
| </dd> |
| <dt><samp class="option">prog <var class="var">integer</var></samp></dt> |
| <dd><p>Sets the progression order to be used by the encoder. |
| Possible values are: |
| </p><dl class="table"> |
| <dt><samp class="option">lrcp</samp></dt> |
| <dt><samp class="option">rlcp</samp></dt> |
| <dt><samp class="option">rpcl</samp></dt> |
| <dt><samp class="option">pcrl</samp></dt> |
| <dt><samp class="option">cprl</samp></dt> |
| </dl> |
| <p>Set to <code class="code">lrcp</code> by default. |
| </p> |
| </dd> |
| <dt><samp class="option">layer_rates <var class="var">string</var></samp></dt> |
| <dd><p>By default, when this option is not used, compression is done using the quality metric. |
| This option allows for compression using compression ratio. The compression ratio for each |
| level could be specified. The compression ratio of a layer <code class="code">l</code> species the what ratio of |
| total file size is contained in the first <code class="code">l</code> layers. |
| </p> |
| <p>Example usage: |
| </p> |
| <div class="example"> |
| <pre class="example-preformatted">ffmpeg -i input.bmp -c:v jpeg2000 -layer_rates "100,10,1" output.j2k |
| </pre></div> |
|
|
| <p>This would compress the image to contain 3 layers, where the data contained in the |
| first layer would be compressed by 1000 times, compressed by 100 in the first two layers, |
| and shall contain all data while using all 3 layers. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="librav1e"></a> |
| <h3 class="section">9.7 librav1e<span class="pull-right"><a class="anchor hidden-xs" href="#librav1e" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-librav1e" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>rav1e AV1 encoder wrapper. |
| </p> |
| <p>Requires the presence of the rav1e headers and library during configuration. |
| You need to explicitly configure the build with <code class="code">--enable-librav1e</code>. |
| </p> |
| <a name="Options-29"></a> |
| <h4 class="subsection">9.7.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-29" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-29" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">qmax</samp></dt> |
| <dd><p>Sets the maximum quantizer to use when using bitrate mode. |
| </p> |
| </dd> |
| <dt><samp class="option">qmin</samp></dt> |
| <dd><p>Sets the minimum quantizer to use when using bitrate mode. |
| </p> |
| </dd> |
| <dt><samp class="option">qp</samp></dt> |
| <dd><p>Uses quantizer mode to encode at the given quantizer (0-255). |
| </p> |
| </dd> |
| <dt><samp class="option">speed</samp></dt> |
| <dd><p>Selects the speed preset (0-10) to encode with. |
| </p> |
| </dd> |
| <dt><samp class="option">tiles</samp></dt> |
| <dd><p>Selects how many tiles to encode with. |
| </p> |
| </dd> |
| <dt><samp class="option">tile-rows</samp></dt> |
| <dd><p>Selects how many rows of tiles to encode with. |
| </p> |
| </dd> |
| <dt><samp class="option">tile-columns</samp></dt> |
| <dd><p>Selects how many columns of tiles to encode with. |
| </p> |
| </dd> |
| <dt><samp class="option">rav1e-params</samp></dt> |
| <dd><p>Set rav1e options using a list of <var class="var">key</var>=<var class="var">value</var> pairs separated |
| by ":". See <code class="command">rav1e --help</code> for a list of options. |
| </p> |
| <p>For example to specify librav1e encoding options with <samp class="option">-rav1e-params</samp>: |
| </p> |
| <div class="example"> |
| <pre class="example-preformatted">ffmpeg -i input -c:v librav1e -b:v 500K -rav1e-params speed=5:low_latency=true output.mp4 |
| </pre></div> |
|
|
| </dd> |
| </dl> |
|
|
| <a name="libaom_002dav1"></a> |
| <h3 class="section">9.8 libaom-av1<span class="pull-right"><a class="anchor hidden-xs" href="#libaom_002dav1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libaom_002dav1" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>libaom AV1 encoder wrapper. |
| </p> |
| <p>Requires the presence of the libaom headers and library during |
| configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libaom</code>. |
| </p> |
| <a name="Options-30"></a> |
| <h4 class="subsection">9.8.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-30" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-30" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The wrapper supports the following standard libavcodec options: |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">b</samp></dt> |
| <dd><p>Set bitrate target in bits/second. By default this will use |
| variable-bitrate mode. If <samp class="option">maxrate</samp> and <samp class="option">minrate</samp> are |
| also set to the same value then it will use constant-bitrate mode, |
| otherwise if <samp class="option">crf</samp> is set as well then it will use |
| constrained-quality mode. |
| </p> |
| </dd> |
| <dt><samp class="option">g keyint_min</samp></dt> |
| <dd><p>Set key frame placement. The GOP size sets the maximum distance between |
| key frames; if zero the output stream will be intra-only. The minimum |
| distance is ignored unless it is the same as the GOP size, in which case |
| key frames will always appear at a fixed interval. Not set by default, |
| so without this option the library has completely free choice about |
| where to place key frames. |
| </p> |
| </dd> |
| <dt><samp class="option">qmin qmax</samp></dt> |
| <dd><p>Set minimum/maximum quantisation values. Valid range is from 0 to 63 |
| (warning: this does not match the quantiser values actually used by AV1 |
| - divide by four to map real quantiser values to this range). Defaults |
| to min/max (no constraint). |
| </p> |
| </dd> |
| <dt><samp class="option">minrate maxrate bufsize rc_init_occupancy</samp></dt> |
| <dd><p>Set rate control buffering parameters. Not used if not set - defaults |
| to unconstrained variable bitrate. |
| </p> |
| </dd> |
| <dt><samp class="option">threads</samp></dt> |
| <dd><p>Set the number of threads to use while encoding. This may require the |
| <samp class="option">tiles</samp> or <samp class="option">row-mt</samp> options to also be set to actually |
| use the specified number of threads fully. Defaults to the number of |
| hardware threads supported by the host machine. |
| </p> |
| </dd> |
| <dt><samp class="option">profile</samp></dt> |
| <dd><p>Set the encoding profile. Defaults to using the profile which matches |
| the bit depth and chroma subsampling of the input. |
| </p> |
| </dd> |
| </dl> |
|
|
| <p>The wrapper also has some specific options: |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">cpu-used</samp></dt> |
| <dd><p>Set the quality/encoding speed tradeoff. Valid range is from 0 to 8, |
| higher numbers indicating greater speed and lower quality. The default |
| value is 1, which will be slow and high quality. |
| </p> |
| </dd> |
| <dt><samp class="option">auto-alt-ref</samp></dt> |
| <dd><p>Enable use of alternate reference frames. Defaults to the internal |
| default of the library. |
| </p> |
| </dd> |
| <dt><samp class="option">arnr-max-frames (<em class="emph">frames</em>)</samp></dt> |
| <dd><p>Set altref noise reduction max frame count. Default is -1. |
| </p> |
| </dd> |
| <dt><samp class="option">arnr-strength (<em class="emph">strength</em>)</samp></dt> |
| <dd><p>Set altref noise reduction filter strength. Range is -1 to 6. Default is -1. |
| </p> |
| </dd> |
| <dt><samp class="option">aq-mode (<em class="emph">aq-mode</em>)</samp></dt> |
| <dd><p>Set adaptive quantization mode. Possible values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">none (<em class="emph">0</em>)</samp>’</dt> |
| <dd><p>Disabled. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">variance (<em class="emph">1</em>)</samp>’</dt> |
| <dd><p>Variance-based. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">complexity (<em class="emph">2</em>)</samp>’</dt> |
| <dd><p>Complexity-based. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">cyclic (<em class="emph">3</em>)</samp>’</dt> |
| <dd><p>Cyclic refresh. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">tune (<em class="emph">tune</em>)</samp></dt> |
| <dd><p>Set the distortion metric the encoder is tuned with. Default is <code class="code">psnr</code>. |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">psnr (<em class="emph">0</em>)</samp>’</dt> |
| <dt>‘<samp class="samp">ssim (<em class="emph">1</em>)</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">lag-in-frames</samp></dt> |
| <dd><p>Set the maximum number of frames which the encoder may keep in flight |
| at any one time for lookahead purposes. Defaults to the internal |
| default of the library. |
| </p> |
| </dd> |
| <dt><samp class="option">error-resilience</samp></dt> |
| <dd><p>Enable error resilience features: |
| </p><dl class="table"> |
| <dt><samp class="option">default</samp></dt> |
| <dd><p>Improve resilience against losses of whole frames. |
| </p></dd> |
| </dl> |
| <p>Not enabled by default. |
| </p> |
| </dd> |
| <dt><samp class="option">crf</samp></dt> |
| <dd><p>Set the quality/size tradeoff for constant-quality (no bitrate target) |
| and constrained-quality (with maximum bitrate target) modes. Valid |
| range is 0 to 63, higher numbers indicating lower quality and smaller |
| output size. Only used if set; by default only the bitrate target is |
| used. |
| </p> |
| </dd> |
| <dt><samp class="option">static-thresh</samp></dt> |
| <dd><p>Set a change threshold on blocks below which they will be skipped by |
| the encoder. Defined in arbitrary units as a nonnegative integer, |
| defaulting to zero (no blocks are skipped). |
| </p> |
| </dd> |
| <dt><samp class="option">drop-threshold</samp></dt> |
| <dd><p>Set a threshold for dropping frames when close to rate control bounds. |
| Defined as a percentage of the target buffer - when the rate control |
| buffer falls below this percentage, frames will be dropped until it |
| has refilled above the threshold. Defaults to zero (no frames are |
| dropped). |
| </p> |
| </dd> |
| <dt><samp class="option">denoise-noise-level (<em class="emph">level</em>)</samp></dt> |
| <dd><p>Amount of noise to be removed for grain synthesis. Grain synthesis is disabled if |
| this option is not set or set to 0. |
| </p> |
| </dd> |
| <dt><samp class="option">denoise-block-size (<em class="emph">pixels</em>)</samp></dt> |
| <dd><p>Block size used for denoising for grain synthesis. If not set, AV1 codec |
| uses the default value of 32. |
| </p> |
| </dd> |
| <dt><samp class="option">undershoot-pct (<em class="emph">pct</em>)</samp></dt> |
| <dd><p>Set datarate undershoot (min) percentage of the target bitrate. Range is -1 to 100. |
| Default is -1. |
| </p> |
| </dd> |
| <dt><samp class="option">overshoot-pct (<em class="emph">pct</em>)</samp></dt> |
| <dd><p>Set datarate overshoot (max) percentage of the target bitrate. Range is -1 to 1000. |
| Default is -1. |
| </p> |
| </dd> |
| <dt><samp class="option">minsection-pct (<em class="emph">pct</em>)</samp></dt> |
| <dd><p>Minimum percentage variation of the GOP bitrate from the target bitrate. If minsection-pct |
| is not set, the libaomenc wrapper computes it as follows: <code class="code">(minrate * 100 / bitrate)</code>. |
| Range is -1 to 100. Default is -1 (unset). |
| </p> |
| </dd> |
| <dt><samp class="option">maxsection-pct (<em class="emph">pct</em>)</samp></dt> |
| <dd><p>Maximum percentage variation of the GOP bitrate from the target bitrate. If maxsection-pct |
| is not set, the libaomenc wrapper computes it as follows: <code class="code">(maxrate * 100 / bitrate)</code>. |
| Range is -1 to 5000. Default is -1 (unset). |
| </p> |
| </dd> |
| <dt><samp class="option">frame-parallel (<em class="emph">boolean</em>)</samp></dt> |
| <dd><p>Enable frame parallel decodability features. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">tiles</samp></dt> |
| <dd><p>Set the number of tiles to encode the input video with, as columns x |
| rows. Larger numbers allow greater parallelism in both encoding and |
| decoding, but may decrease coding efficiency. Defaults to the minimum |
| number of tiles required by the size of the input video (this is 1x1 |
| (that is, a single tile) for sizes up to and including 4K). |
| </p> |
| </dd> |
| <dt><samp class="option">tile-columns tile-rows</samp></dt> |
| <dd><p>Set the number of tiles as log2 of the number of tile rows and columns. |
| Provided for compatibility with libvpx/VP9. |
| </p> |
| </dd> |
| <dt><samp class="option">row-mt (Requires libaom >= 1.0.0-759-g90a15f4f2)</samp></dt> |
| <dd><p>Enable row based multi-threading. Disabled by default. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-cdef (<em class="emph">boolean</em>)</samp></dt> |
| <dd><p>Enable Constrained Directional Enhancement Filter. The libaom-av1 |
| encoder enables CDEF by default. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-restoration (<em class="emph">boolean</em>)</samp></dt> |
| <dd><p>Enable Loop Restoration Filter. Default is true for libaom-av1. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-global-motion (<em class="emph">boolean</em>)</samp></dt> |
| <dd><p>Enable the use of global motion for block prediction. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-intrabc (<em class="emph">boolean</em>)</samp></dt> |
| <dd><p>Enable block copy mode for intra block prediction. This mode is |
| useful for screen content. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-rect-partitions (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable rectangular partitions. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-1to4-partitions (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable 1:4/4:1 partitions. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-ab-partitions (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable AB shape partitions. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-angle-delta (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable angle delta intra prediction. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-cfl-intra (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable chroma predicted from luma intra prediction. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-filter-intra (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable filter intra predictor. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-intra-edge-filter (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable intra edge filter. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-smooth-intra (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable smooth intra prediction mode. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-paeth-intra (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable paeth predictor in intra prediction. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-palette (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable palette prediction mode. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-flip-idtx (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable extended transform type, including FLIPADST_DCT, DCT_FLIPADST, |
| FLIPADST_FLIPADST, ADST_FLIPADST, FLIPADST_ADST, IDTX, V_DCT, H_DCT, |
| V_ADST, H_ADST, V_FLIPADST, H_FLIPADST. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-tx64 (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable 64-pt transform. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">reduced-tx-type-set (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Use reduced set of transform types. Default is false. |
| </p> |
| </dd> |
| <dt><samp class="option">use-intra-dct-only (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Use DCT only for INTRA modes. Default is false. |
| </p> |
| </dd> |
| <dt><samp class="option">use-inter-dct-only (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Use DCT only for INTER modes. Default is false. |
| </p> |
| </dd> |
| <dt><samp class="option">use-intra-default-tx-only (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Use Default-transform only for INTRA modes. Default is false. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-ref-frame-mvs (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable temporal mv prediction. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-reduced-reference-set (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Use reduced set of single and compound references. Default is false. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-obmc (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable obmc. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-dual-filter (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable dual filter. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-diff-wtd-comp (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable difference-weighted compound. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-dist-wtd-comp (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable distance-weighted compound. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-onesided-comp (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable one sided compound. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-interinter-wedge (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable interinter wedge compound. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-interintra-wedge (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable interintra wedge compound. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-masked-comp (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable masked compound. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-interintra-comp (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable interintra compound. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">enable-smooth-interintra (<em class="emph">boolean</em>) (Requires libaom >= v2.0.0)</samp></dt> |
| <dd><p>Enable smooth interintra mode. Default is true. |
| </p> |
| </dd> |
| <dt><samp class="option">aom-params</samp></dt> |
| <dd><p>Set libaom options using a list of <var class="var">key</var>=<var class="var">value</var> pairs separated |
| by ":". For a list of supported options, see <code class="command">aomenc --help</code> under the |
| section "AV1 Specific Options". |
| </p> |
| <p>For example to specify libaom encoding options with <samp class="option">-aom-params</samp>: |
| </p> |
| <div class="example"> |
| <pre class="example-preformatted">ffmpeg -i input -c:v libaom-av1 -b:v 500K -aom-params tune=psnr:enable-tpl-model=1 output.mp4 |
| </pre></div> |
|
|
| </dd> |
| </dl> |
|
|
| <a name="liboapv"></a> |
| <h3 class="section">9.9 liboapv<span class="pull-right"><a class="anchor hidden-xs" href="#liboapv" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-liboapv" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Advanced Professional Video codec encoder wrapper. |
| </p> |
| <p>This encoder requires the presence of the liboapv headers and library |
| during configuration. You need to explicitly configure the build with |
| <samp class="option">--enable-liboapv</samp>. |
| </p> |
| <div class="info"> |
| <p>Many liboapv encoder options are mapped to FFmpeg global codec options, |
| while unique encoder options are provided through private options. |
| </p></div> |
| <p>The apv project website is at <a class="url" href="https://github.com/AcademySoftwareFoundation/openapv">https://github.com/AcademySoftwareFoundation/openapv</a>. |
| </p> |
| <a name="Options-31"></a> |
| <h4 class="subsection">9.9.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-31" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-31" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following options are supported by the liboapv wrapper. |
| </p> |
| <div class="info"> |
| <p>To get a more extensive documentation of the liboapv options, consult the |
| liboapv documentation. |
| </p></div> |
| <dl class="table"> |
| <dt><samp class="option">preset</samp></dt> |
| <dd><p>Set the quality-speed tradeoff [fastest, fast, medium, slow, placebo, default] |
| </p> |
| </dd> |
| <dt><samp class="option">qp</samp></dt> |
| <dd><p>Set the quantization parameter value for CQP rate control mode. |
| </p> |
| </dd> |
| <dt><samp class="option">oapv-params (<em class="emph">parse_apv_params</em>)</samp></dt> |
| <dd><p>Set liboapvenc options using a list of <var class="var">key</var>=<var class="var">value</var> pairs separated |
| by ":". See the liboapv encoder user guide for a list of accepted parameters. |
| </p></dd> |
| </dl> |
|
|
| <a name="libsvtav1"></a> |
| <h3 class="section">9.10 libsvtav1<span class="pull-right"><a class="anchor hidden-xs" href="#libsvtav1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libsvtav1" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>SVT-AV1 encoder wrapper. |
| </p> |
| <p>Requires the presence of the SVT-AV1 headers and library during configuration. |
| You need to explicitly configure the build with <code class="code">--enable-libsvtav1</code>. |
| </p> |
| <a name="Options-32"></a> |
| <h4 class="subsection">9.10.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-32" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-32" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">profile</samp></dt> |
| <dd><p>Set the encoding profile. |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">main</samp>’</dt> |
| <dt>‘<samp class="samp">high</samp>’</dt> |
| <dt>‘<samp class="samp">professional</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">level</samp></dt> |
| <dd><p>Set the operating point level. For example: ’4.0’ |
| </p> |
| </dd> |
| <dt><samp class="option">hielevel</samp></dt> |
| <dd><p>Set the Hierarchical prediction levels. |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">3level</samp>’</dt> |
| <dt>‘<samp class="samp">4level</samp>’</dt> |
| <dd><p>This is the default. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">tier</samp></dt> |
| <dd><p>Set the operating point tier. |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">main</samp>’</dt> |
| <dd><p>This is the default. |
| </p></dd> |
| <dt>‘<samp class="samp">high</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">qmax</samp></dt> |
| <dd><p>Set the maximum quantizer to use when using a bitrate mode. |
| </p> |
| </dd> |
| <dt><samp class="option">qmin</samp></dt> |
| <dd><p>Set the minimum quantizer to use when using a bitrate mode. |
| </p> |
| </dd> |
| <dt><samp class="option">crf</samp></dt> |
| <dd><p>Constant rate factor value used in crf rate control mode (0-63). |
| </p> |
| </dd> |
| <dt><samp class="option">qp</samp></dt> |
| <dd><p>Set the quantizer used in cqp rate control mode (0-63). |
| </p> |
| </dd> |
| <dt><samp class="option">sc_detection</samp></dt> |
| <dd><p>Enable scene change detection. |
| </p> |
| </dd> |
| <dt><samp class="option">la_depth</samp></dt> |
| <dd><p>Set number of frames to look ahead (0-120). |
| </p> |
| </dd> |
| <dt><samp class="option">preset</samp></dt> |
| <dd><p>Set the quality-speed tradeoff, in the range 0 to 13. Higher values are |
| faster but lower quality. |
| </p> |
| </dd> |
| <dt><samp class="option">tile_rows</samp></dt> |
| <dd><p>Set log2 of the number of rows of tiles to use (0-6). |
| </p> |
| </dd> |
| <dt><samp class="option">tile_columns</samp></dt> |
| <dd><p>Set log2 of the number of columns of tiles to use (0-4). |
| </p> |
| </dd> |
| <dt><samp class="option">svtav1-params</samp></dt> |
| <dd><p>Set SVT-AV1 options using a list of <var class="var">key</var>=<var class="var">value</var> pairs separated |
| by ":". See the SVT-AV1 encoder user guide for a list of accepted parameters. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="libsvtjpegxs"></a> |
| <h3 class="section">9.11 libsvtjpegxs<span class="pull-right"><a class="anchor hidden-xs" href="#libsvtjpegxs" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libsvtjpegxs" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>SVT-JPEG-XS encoder wrapper. |
| </p> |
| <p>Requires the presence of the SVT-JPEG-XS headers and library during configuration. |
| You need to explicitly configure the build with <code class="code">--enable-libsvtjpegxs</code>. |
| </p> |
| <a name="Options-33"></a> |
| <h4 class="subsection">9.11.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-33" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-33" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">decomp_v</samp></dt> |
| <dd><p>Set vertical decomposition level |
| </p></dd> |
| <dt><samp class="option">decomp_h</samp></dt> |
| <dd><p>Set horizontal decomposition level |
| </p> |
| </dd> |
| <dt><samp class="option">quantization</samp></dt> |
| <dd><p>Set the quantization algorithm. |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">deadzone</samp>’</dt> |
| <dt>‘<samp class="samp">uniform</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">coding-signs</samp></dt> |
| <dd><p>Enable Signs handling strategy |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">disable</samp>’</dt> |
| <dt>‘<samp class="samp">fast</samp>’</dt> |
| <dt>‘<samp class="samp">full</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">coding-sigf</samp></dt> |
| <dd><p>Enable Significance coding |
| </p> |
| </dd> |
| <dt><samp class="option">coding-vpred</samp></dt> |
| <dd><p>Enable Vertical Prediction coding |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">disable</samp>’</dt> |
| <dt>‘<samp class="samp">no_residuals</samp>’</dt> |
| <dt>‘<samp class="samp">no_coeffs</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
| <a name="libjxl"></a> |
| <h3 class="section">9.12 libjxl<span class="pull-right"><a class="anchor hidden-xs" href="#libjxl" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libjxl" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>libjxl JPEG XL encoder wrapper. |
| </p> |
| <p>Requires the presence of the libjxl headers and library during |
| configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libjxl</code>. |
| </p> |
| <a name="Options-34"></a> |
| <h4 class="subsection">9.12.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-34" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-34" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The libjxl wrapper supports the following options: |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">distance</samp></dt> |
| <dd><p>Set the target Butteraugli distance. This is a quality setting: lower |
| distance yields higher quality, with distance=1.0 roughly comparable to |
| libjpeg Quality 90 for photographic content. Setting distance=0.0 yields |
| true lossless encoding. Valid values range between 0.0 and 15.0, and sane |
| values rarely exceed 5.0. Setting distance=0.1 usually attains |
| transparency for most input. The default is 1.0. |
| </p> |
| </dd> |
| <dt><samp class="option">effort</samp></dt> |
| <dd><p>Set the encoding effort used. Higher effort values produce more consistent |
| quality and usually produces a better quality/bpp curve, at the cost of |
| more CPU time required. Valid values range from 1 to 9, and the default is 7. |
| </p> |
| </dd> |
| <dt><samp class="option">modular</samp></dt> |
| <dd><p>Force the encoder to use Modular mode instead of choosing automatically. The |
| default is to use VarDCT for lossy encoding and Modular for lossless. VarDCT |
| is generally superior to Modular for lossy encoding but does not support |
| lossless encoding. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="libkvazaar"></a> |
| <h3 class="section">9.13 libkvazaar<span class="pull-right"><a class="anchor hidden-xs" href="#libkvazaar" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libkvazaar" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Kvazaar H.265/HEVC encoder. |
| </p> |
| <p>Requires the presence of the libkvazaar headers and library during |
| configuration. You need to explicitly configure the build with |
| <samp class="option">--enable-libkvazaar</samp>. |
| </p> |
| <a name="Options-35"></a> |
| <h4 class="subsection">9.13.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-35" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-35" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">b</samp></dt> |
| <dd><p>Set target video bitrate in bit/s and enable rate control. |
| </p> |
| </dd> |
| <dt><samp class="option">kvazaar-params</samp></dt> |
| <dd><p>Set kvazaar parameters as a list of <var class="var">name</var>=<var class="var">value</var> pairs separated |
| by commas (,). See kvazaar documentation for a list of options. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="libopenh264"></a> |
| <h3 class="section">9.14 libopenh264<span class="pull-right"><a class="anchor hidden-xs" href="#libopenh264" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libopenh264" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Cisco libopenh264 H.264/MPEG-4 AVC encoder wrapper. |
| </p> |
| <p>This encoder requires the presence of the libopenh264 headers and |
| library during configuration. You need to explicitly configure the |
| build with <code class="code">--enable-libopenh264</code>. The library is detected using |
| <code class="command">pkg-config</code>. |
| </p> |
| <p>For more information about the library see |
| <a class="url" href="http://www.openh264.org">http://www.openh264.org</a>. |
| </p> |
| <a name="Options-36"></a> |
| <h4 class="subsection">9.14.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-36" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-36" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following FFmpeg global options affect the configurations of the |
| libopenh264 encoder. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">b</samp></dt> |
| <dd><p>Set the bitrate (as a number of bits per second). |
| </p> |
| </dd> |
| <dt><samp class="option">g</samp></dt> |
| <dd><p>Set the GOP size. |
| </p> |
| </dd> |
| <dt><samp class="option">maxrate</samp></dt> |
| <dd><p>Set the max bitrate (as a number of bits per second). |
| </p> |
| </dd> |
| <dt><samp class="option">flags +global_header</samp></dt> |
| <dd><p>Set global header in the bitstream. |
| </p> |
| </dd> |
| <dt><samp class="option">slices</samp></dt> |
| <dd><p>Set the number of slices, used in parallelized encoding. Default value |
| is 0. This is only used when <samp class="option">slice_mode</samp> is set to |
| ‘<samp class="samp">fixed</samp>’. |
| </p> |
| </dd> |
| <dt><samp class="option">loopfilter</samp></dt> |
| <dd><p>Enable loop filter, if set to 1 (automatically enabled). To disable |
| set a value of 0. |
| </p> |
| </dd> |
| <dt><samp class="option">profile</samp></dt> |
| <dd><p>Set profile restrictions. If set to the value of ‘<samp class="samp">main</samp>’ enable |
| CABAC (set the <code class="code">SEncParamExt.iEntropyCodingModeFlag</code> flag to 1). |
| </p> |
| </dd> |
| <dt><samp class="option">max_nal_size</samp></dt> |
| <dd><p>Set maximum NAL size in bytes. |
| </p> |
| </dd> |
| <dt><samp class="option">allow_skip_frames</samp></dt> |
| <dd><p>Allow skipping frames to hit the target bitrate if set to 1. |
| </p></dd> |
| </dl> |
|
|
| <a name="libtheora"></a> |
| <h3 class="section">9.15 libtheora<span class="pull-right"><a class="anchor hidden-xs" href="#libtheora" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libtheora" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>libtheora Theora encoder wrapper. |
| </p> |
| <p>Requires the presence of the libtheora headers and library during |
| configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libtheora</code>. |
| </p> |
| <p>For more information about the libtheora project see |
| <a class="url" href="http://www.theora.org/">http://www.theora.org/</a>. |
| </p> |
| <a name="Options-37"></a> |
| <h4 class="subsection">9.15.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-37" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-37" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following global options are mapped to internal libtheora options |
| which affect the quality and the bitrate of the encoded stream. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">b</samp></dt> |
| <dd><p>Set the video bitrate in bit/s for CBR (Constant Bit Rate) mode. In |
| case VBR (Variable Bit Rate) mode is enabled this option is ignored. |
| </p> |
| </dd> |
| <dt><samp class="option">flags</samp></dt> |
| <dd><p>Used to enable constant quality mode (VBR) encoding through the |
| <samp class="option">qscale</samp> flag, and to enable the <code class="code">pass1</code> and <code class="code">pass2</code> |
| modes. |
| </p> |
| </dd> |
| <dt><samp class="option">g</samp></dt> |
| <dd><p>Set the GOP size. |
| </p> |
| </dd> |
| <dt><samp class="option">global_quality</samp></dt> |
| <dd><p>Set the global quality as an integer in lambda units. |
| </p> |
| <p>Only relevant when VBR mode is enabled with <code class="code">flags +qscale</code>. The |
| value is converted to QP units by dividing it by <code class="code">FF_QP2LAMBDA</code>, |
| clipped in the [0 - 10] range, and then multiplied by 6.3 to get a |
| value in the native libtheora range [0-63]. A higher value corresponds |
| to a higher quality. |
| </p> |
| </dd> |
| <dt><samp class="option">q</samp></dt> |
| <dd><p>Enable VBR mode when set to a non-negative value, and set constant |
| quality value as a double floating point value in QP units. |
| </p> |
| <p>The value is clipped in the [0-10] range, and then multiplied by 6.3 |
| to get a value in the native libtheora range [0-63]. |
| </p> |
| <p>This option is valid only using the <code class="command">ffmpeg</code> command-line |
| tool. For library interface users, use <samp class="option">global_quality</samp>. |
| </p></dd> |
| </dl> |
|
|
| <a name="Examples-1"></a> |
| <h4 class="subsection">9.15.2 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples-1" aria-hidden="true">TOC</a></span></h4> |
|
|
| <ul class="itemize mark-bullet"> |
| <li>Set maximum constant quality (VBR) encoding with <code class="command">ffmpeg</code>: |
| <div class="example"> |
| <pre class="example-preformatted">ffmpeg -i INPUT -codec:v libtheora -q:v 10 OUTPUT.ogg |
| </pre></div> |
|
|
| </li><li>Use <code class="command">ffmpeg</code> to convert a CBR 1000 kbps Theora video stream: |
| <div class="example"> |
| <pre class="example-preformatted">ffmpeg -i INPUT -codec:v libtheora -b:v 1000k OUTPUT.ogg |
| </pre></div> |
| </li></ul> |
|
|
| <a name="libvpx"></a> |
| <h3 class="section">9.16 libvpx<span class="pull-right"><a class="anchor hidden-xs" href="#libvpx" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libvpx" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>VP8/VP9 format supported through libvpx. |
| </p> |
| <p>Requires the presence of the libvpx headers and library during configuration. |
| You need to explicitly configure the build with <code class="code">--enable-libvpx</code>. |
| </p> |
| <a name="Options-38"></a> |
| <h4 class="subsection">9.16.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-38" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-38" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following options are supported by the libvpx wrapper. The |
| <code class="command">vpxenc</code>-equivalent options or values are listed in parentheses |
| for easy migration. |
| </p> |
| <p>To reduce the duplication of documentation, only the private options |
| and some others requiring special attention are documented here. For |
| the documentation of the undocumented generic options, see |
| <a class="ref" href="#codec_002doptions">the Codec Options chapter</a>. |
| </p> |
| <p>To get more documentation of the libvpx options, invoke the command |
| <code class="command">ffmpeg -h encoder=libvpx</code>, <code class="command">ffmpeg -h encoder=libvpx-vp9</code> or |
| <code class="command">vpxenc --help</code>. Further information is available in the libvpx API |
| documentation. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">b (<em class="emph">target-bitrate</em>)</samp></dt> |
| <dd><p>Set bitrate in bits/s. Note that FFmpeg’s <samp class="option">b</samp> option is |
| expressed in bits/s, while <code class="command">vpxenc</code>’s <samp class="option">target-bitrate</samp> is in |
| kilobits/s. |
| </p> |
| </dd> |
| <dt><samp class="option">g (<em class="emph">kf-max-dist</em>)</samp></dt> |
| <dt><samp class="option">keyint_min (<em class="emph">kf-min-dist</em>)</samp></dt> |
| <dt><samp class="option">qmin (<em class="emph">min-q</em>)</samp></dt> |
| <dd><p>Minimum (Best Quality) Quantizer. |
| </p> |
| </dd> |
| <dt><samp class="option">qmax (<em class="emph">max-q</em>)</samp></dt> |
| <dd><p>Maximum (Worst Quality) Quantizer. |
| Can be changed per-frame. |
| </p> |
| </dd> |
| <dt><samp class="option">bufsize (<em class="emph">buf-sz</em>, <em class="emph">buf-optimal-sz</em>)</samp></dt> |
| <dd><p>Set ratecontrol buffer size (in bits). Note <code class="command">vpxenc</code>’s options are |
| specified in milliseconds, the libvpx wrapper converts this value as follows: |
| <code class="code">buf-sz = bufsize * 1000 / bitrate</code>, |
| <code class="code">buf-optimal-sz = bufsize * 1000 / bitrate * 5 / 6</code>. |
| </p> |
| </dd> |
| <dt><samp class="option">rc_init_occupancy (<em class="emph">buf-initial-sz</em>)</samp></dt> |
| <dd><p>Set number of bits which should be loaded into the rc buffer before decoding |
| starts. Note <code class="command">vpxenc</code>’s option is specified in milliseconds, the libvpx |
| wrapper converts this value as follows: |
| <code class="code">rc_init_occupancy * 1000 / bitrate</code>. |
| </p> |
| </dd> |
| <dt><samp class="option">undershoot-pct</samp></dt> |
| <dd><p>Set datarate undershoot (min) percentage of the target bitrate. |
| </p> |
| </dd> |
| <dt><samp class="option">overshoot-pct</samp></dt> |
| <dd><p>Set datarate overshoot (max) percentage of the target bitrate. |
| </p> |
| </dd> |
| <dt><samp class="option">skip_threshold (<em class="emph">drop-frame</em>)</samp></dt> |
| <dt><samp class="option">qcomp (<em class="emph">bias-pct</em>)</samp></dt> |
| <dt><samp class="option">maxrate (<em class="emph">maxsection-pct</em>)</samp></dt> |
| <dd><p>Set GOP max bitrate in bits/s. Note <code class="command">vpxenc</code>’s option is specified as a |
| percentage of the target bitrate, the libvpx wrapper converts this value as |
| follows: <code class="code">(maxrate * 100 / bitrate)</code>. |
| </p> |
| </dd> |
| <dt><samp class="option">minrate (<em class="emph">minsection-pct</em>)</samp></dt> |
| <dd><p>Set GOP min bitrate in bits/s. Note <code class="command">vpxenc</code>’s option is specified as a |
| percentage of the target bitrate, the libvpx wrapper converts this value as |
| follows: <code class="code">(minrate * 100 / bitrate)</code>. |
| </p> |
| </dd> |
| <dt><samp class="option">minrate, maxrate, b <em class="emph">end-usage=cbr</em></samp></dt> |
| <dd><p><code class="code">(minrate == maxrate == bitrate)</code>. |
| </p> |
| </dd> |
| <dt><samp class="option">crf (<em class="emph">end-usage=cq</em>, <em class="emph">cq-level</em>)</samp></dt> |
| <dt><samp class="option">tune (<em class="emph">tune</em>)</samp></dt> |
| <dd><dl class="table"> |
| <dt>‘<samp class="samp">psnr (<em class="emph">psnr</em>)</samp>’</dt> |
| <dt>‘<samp class="samp">ssim (<em class="emph">ssim</em>)</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">quality, deadline (<em class="emph">deadline</em>)</samp></dt> |
| <dd><dl class="table"> |
| <dt>‘<samp class="samp">best</samp>’</dt> |
| <dd><p>Use best quality deadline. Poorly named and quite slow, this option should be |
| avoided as it may give worse quality output than good. |
| </p></dd> |
| <dt>‘<samp class="samp">good</samp>’</dt> |
| <dd><p>Use good quality deadline. This is a good trade-off between speed and quality |
| when used with the <samp class="option">cpu-used</samp> option. |
| </p></dd> |
| <dt>‘<samp class="samp">realtime</samp>’</dt> |
| <dd><p>Use realtime quality deadline. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">speed, cpu-used (<em class="emph">cpu-used</em>)</samp></dt> |
| <dd><p>Set quality/speed ratio modifier. Higher values speed up the encode at the cost |
| of quality. |
| </p> |
| </dd> |
| <dt><samp class="option">nr (<em class="emph">noise-sensitivity</em>)</samp></dt> |
| <dt><samp class="option">static-thresh</samp></dt> |
| <dd><p>Set a change threshold on blocks below which they will be skipped by the |
| encoder. |
| </p> |
| </dd> |
| <dt><samp class="option">slices (<em class="emph">token-parts</em>)</samp></dt> |
| <dd><p>Note that FFmpeg’s <samp class="option">slices</samp> option gives the total number of partitions, |
| while <code class="command">vpxenc</code>’s <samp class="option">token-parts</samp> is given as |
| <code class="code">log2(partitions)</code>. |
| </p> |
| </dd> |
| <dt><samp class="option">max-intra-rate</samp></dt> |
| <dd><p>Set maximum I-frame bitrate as a percentage of the target bitrate. A value of 0 |
| means unlimited. |
| </p> |
| </dd> |
| <dt><samp class="option">force_key_frames</samp></dt> |
| <dd><p><code class="code">VPX_EFLAG_FORCE_KF</code> |
| </p> |
| </dd> |
| <dt><samp class="option">Alternate reference frame related</samp></dt> |
| <dd><dl class="table"> |
| <dt><samp class="option">auto-alt-ref</samp></dt> |
| <dd><p>Enable use of alternate reference frames (2-pass only). |
| Values greater than 1 enable multi-layer alternate reference frames (VP9 only). |
| </p></dd> |
| <dt><samp class="option">arnr-maxframes</samp></dt> |
| <dd><p>Set altref noise reduction max frame count. |
| </p></dd> |
| <dt><samp class="option">arnr-type</samp></dt> |
| <dd><p>Set altref noise reduction filter type: backward, forward, centered. |
| </p></dd> |
| <dt><samp class="option">arnr-strength</samp></dt> |
| <dd><p>Set altref noise reduction filter strength. |
| </p></dd> |
| <dt><samp class="option">rc-lookahead, lag-in-frames (<em class="emph">lag-in-frames</em>)</samp></dt> |
| <dd><p>Set number of frames to look ahead for frametype and ratecontrol. |
| </p></dd> |
| <dt><samp class="option">min-gf-interval</samp></dt> |
| <dd><p>Set minimum golden/alternate reference frame interval (VP9 only). |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">error-resilient</samp></dt> |
| <dd><p>Enable error resiliency features. |
| </p> |
| </dd> |
| <dt><samp class="option">sharpness <var class="var">integer</var></samp></dt> |
| <dd><p>Increase sharpness at the expense of lower PSNR. |
| The valid range is [0, 7]. |
| </p> |
| </dd> |
| <dt><samp class="option">ts-parameters</samp></dt> |
| <dd><p>Sets the temporal scalability configuration using a :-separated list of |
| key=value pairs. For example, to specify temporal scalability parameters |
| with <code class="code">ffmpeg</code>: |
| </p><div class="example"> |
| <pre class="example-preformatted">ffmpeg -i INPUT -c:v libvpx -ts-parameters ts_number_layers=3:\ |
| ts_target_bitrate=250,500,1000:ts_rate_decimator=4,2,1:\ |
| ts_periodicity=4:ts_layer_id=0,2,1,2:ts_layering_mode=3 OUTPUT |
| </pre></div> |
| <p>Below is a brief explanation of each of the parameters, please |
| refer to <code class="code">struct vpx_codec_enc_cfg</code> in <code class="code">vpx/vpx_encoder.h</code> for more |
| details. |
| </p><dl class="table"> |
| <dt><samp class="option">ts_number_layers</samp></dt> |
| <dd><p>Number of temporal coding layers. |
| </p></dd> |
| <dt><samp class="option">ts_target_bitrate</samp></dt> |
| <dd><p>Target bitrate for each temporal layer (in kbps). |
| (bitrate should be inclusive of the lower temporal layer). |
| </p></dd> |
| <dt><samp class="option">ts_rate_decimator</samp></dt> |
| <dd><p>Frame rate decimation factor for each temporal layer. |
| </p></dd> |
| <dt><samp class="option">ts_periodicity</samp></dt> |
| <dd><p>Length of the sequence defining frame temporal layer membership. |
| </p></dd> |
| <dt><samp class="option">ts_layer_id</samp></dt> |
| <dd><p>Template defining the membership of frames to temporal layers. |
| </p></dd> |
| <dt><samp class="option">ts_layering_mode</samp></dt> |
| <dd><p>(optional) Selecting the temporal structure from a set of pre-defined temporal layering modes. |
| Currently supports the following options. |
| </p><dl class="table"> |
| <dt><samp class="option">0</samp></dt> |
| <dd><p>No temporal layering flags are provided internally, |
| relies on flags being passed in using <code class="code">metadata</code> field in <code class="code">AVFrame</code> |
| with following keys. |
| </p><dl class="table"> |
| <dt><samp class="option">vp8-flags</samp></dt> |
| <dd><p>Sets the flags passed into the encoder to indicate the referencing scheme for |
| the current frame. |
| Refer to function <code class="code">vpx_codec_encode</code> in <code class="code">vpx/vpx_encoder.h</code> for more |
| details. |
| </p></dd> |
| <dt><samp class="option">temporal_id</samp></dt> |
| <dd><p>Explicitly sets the temporal id of the current frame to encode. |
| </p></dd> |
| </dl> |
| </dd> |
| <dt><samp class="option">2</samp></dt> |
| <dd><p>Two temporal layers. 0-1... |
| </p></dd> |
| <dt><samp class="option">3</samp></dt> |
| <dd><p>Three temporal layers. 0-2-1-2...; with single reference frame. |
| </p></dd> |
| <dt><samp class="option">4</samp></dt> |
| <dd><p>Same as option "3", except there is a dependency between |
| the two temporal layer 2 frames within the temporal period. |
| </p></dd> |
| </dl> |
| </dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">VP8-specific options</samp></dt> |
| <dd><dl class="table"> |
| <dt><samp class="option">screen-content-mode</samp></dt> |
| <dd><p>Screen content mode, one of: 0 (off), 1 (screen), 2 (screen with more aggressive rate control). |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">VP9-specific options</samp></dt> |
| <dd><dl class="table"> |
| <dt><samp class="option">lossless</samp></dt> |
| <dd><p>Enable lossless mode. |
| </p></dd> |
| <dt><samp class="option">tile-columns</samp></dt> |
| <dd><p>Set number of tile columns to use. Note this is given as |
| <code class="code">log2(tile_columns)</code>. For example, 8 tile columns would be requested by |
| setting the <samp class="option">tile-columns</samp> option to 3. |
| </p></dd> |
| <dt><samp class="option">tile-rows</samp></dt> |
| <dd><p>Set number of tile rows to use. Note this is given as <code class="code">log2(tile_rows)</code>. |
| For example, 4 tile rows would be requested by setting the <samp class="option">tile-rows</samp> |
| option to 2. |
| </p></dd> |
| <dt><samp class="option">frame-parallel</samp></dt> |
| <dd><p>Enable frame parallel decodability features. |
| </p></dd> |
| <dt><samp class="option">aq-mode</samp></dt> |
| <dd><p>Set adaptive quantization mode (0: off (default), 1: variance 2: complexity, 3: |
| cyclic refresh, 4: equator360). |
| </p></dd> |
| <dt><samp class="option">colorspace <em class="emph">color-space</em></samp></dt> |
| <dd><p>Set input color space. The VP9 bitstream supports signaling the following |
| colorspaces: |
| </p><dl class="table"> |
| <dt><samp class="option">‘<samp class="samp">rgb</samp>’ <em class="emph">sRGB</em></samp></dt> |
| <dt><samp class="option">‘<samp class="samp">bt709</samp>’ <em class="emph">bt709</em></samp></dt> |
| <dt><samp class="option">‘<samp class="samp">unspecified</samp>’ <em class="emph">unknown</em></samp></dt> |
| <dt><samp class="option">‘<samp class="samp">bt470bg</samp>’ <em class="emph">bt601</em></samp></dt> |
| <dt><samp class="option">‘<samp class="samp">smpte170m</samp>’ <em class="emph">smpte170</em></samp></dt> |
| <dt><samp class="option">‘<samp class="samp">smpte240m</samp>’ <em class="emph">smpte240</em></samp></dt> |
| <dt><samp class="option">‘<samp class="samp">bt2020_ncl</samp>’ <em class="emph">bt2020</em></samp></dt> |
| </dl> |
| </dd> |
| <dt><samp class="option">row-mt <var class="var">boolean</var></samp></dt> |
| <dd><p>Enable row based multi-threading. |
| </p></dd> |
| <dt><samp class="option">tune-content</samp></dt> |
| <dd><p>Set content type: default (0), screen (1), film (2). |
| </p></dd> |
| <dt><samp class="option">corpus-complexity</samp></dt> |
| <dd><p>Corpus VBR mode is a variant of standard VBR where the complexity distribution |
| midpoint is passed in rather than calculated for a specific clip or chunk. |
| </p> |
| <p>The valid range is [0, 10000]. 0 (default) uses standard VBR. |
| </p></dd> |
| <dt><samp class="option">enable-tpl <var class="var">boolean</var></samp></dt> |
| <dd><p>Enable temporal dependency model. |
| </p></dd> |
| <dt><samp class="option">ref-frame-config</samp></dt> |
| <dd><p>Using per-frame metadata, set members of the structure <code class="code">vpx_svc_ref_frame_config_t</code> in <code class="code">vpx/vp8cx.h</code> to fine-control referencing schemes and frame buffer management. |
| <br>Use a :-separated list of key=value pairs. |
| For example, |
| </p><div class="example"> |
| <pre class="example-preformatted">av_dict_set(&av_frame->metadata, "ref-frame-config", \ |
| "rfc_update_buffer_slot=7:rfc_lst_fb_idx=0:rfc_gld_fb_idx=1:rfc_alt_fb_idx=2:rfc_reference_last=0:rfc_reference_golden=0:rfc_reference_alt_ref=0"); |
| </pre></div> |
| <dl class="table"> |
| <dt><samp class="option">rfc_update_buffer_slot</samp></dt> |
| <dd><p>Indicates the buffer slot number to update |
| </p></dd> |
| <dt><samp class="option">rfc_update_last</samp></dt> |
| <dd><p>Indicates whether to update the LAST frame |
| </p></dd> |
| <dt><samp class="option">rfc_update_golden</samp></dt> |
| <dd><p>Indicates whether to update GOLDEN frame |
| </p></dd> |
| <dt><samp class="option">rfc_update_alt_ref</samp></dt> |
| <dd><p>Indicates whether to update ALT_REF frame |
| </p></dd> |
| <dt><samp class="option">rfc_lst_fb_idx</samp></dt> |
| <dd><p>LAST frame buffer index |
| </p></dd> |
| <dt><samp class="option">rfc_gld_fb_idx</samp></dt> |
| <dd><p>GOLDEN frame buffer index |
| </p></dd> |
| <dt><samp class="option">rfc_alt_fb_idx</samp></dt> |
| <dd><p>ALT_REF frame buffer index |
| </p></dd> |
| <dt><samp class="option">rfc_reference_last</samp></dt> |
| <dd><p>Indicates whether to reference LAST frame |
| </p></dd> |
| <dt><samp class="option">rfc_reference_golden</samp></dt> |
| <dd><p>Indicates whether to reference GOLDEN frame |
| </p></dd> |
| <dt><samp class="option">rfc_reference_alt_ref</samp></dt> |
| <dd><p>Indicates whether to reference ALT_REF frame |
| </p></dd> |
| <dt><samp class="option">rfc_reference_duration</samp></dt> |
| <dd><p>Indicates frame duration |
| </p></dd> |
| </dl> |
| </dd> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
| <p>For more information about libvpx see: |
| <a class="url" href="http://www.webmproject.org/">http://www.webmproject.org/</a> |
| </p> |
| <a name="libvvenc"></a> |
| <h3 class="section">9.17 libvvenc<span class="pull-right"><a class="anchor hidden-xs" href="#libvvenc" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libvvenc" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>VVenC H.266/VVC encoder wrapper. |
| </p> |
| <p>This encoder requires the presence of the libvvenc headers and library |
| during configuration. You need to explicitly configure the build with |
| <samp class="option">--enable-libvvenc</samp>. |
| </p> |
| <p>The VVenC project website is at |
| <a class="url" href="https://github.com/fraunhoferhhi/vvenc">https://github.com/fraunhoferhhi/vvenc</a>. |
| </p> |
| <a name="Supported-Pixel-Formats"></a> |
| <h4 class="subsection">9.17.1 Supported Pixel Formats<span class="pull-right"><a class="anchor hidden-xs" href="#Supported-Pixel-Formats" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Supported-Pixel-Formats" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>VVenC supports only 10-bit color spaces as input. But the internal (encoded) |
| bit depth can be set to 8-bit or 10-bit at runtime. |
| </p> |
| <a name="Options-39"></a> |
| <h4 class="subsection">9.17.2 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-39" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-39" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">b</samp></dt> |
| <dd><p>Sets target video bitrate. |
| </p> |
| </dd> |
| <dt><samp class="option">g</samp></dt> |
| <dd><p>Set the GOP size. Currently support for g=1 (Intra only) or default. |
| </p> |
| </dd> |
| <dt><samp class="option">preset</samp></dt> |
| <dd><p>Set the VVenC preset. |
| </p> |
| </dd> |
| <dt><samp class="option">levelidc</samp></dt> |
| <dd><p>Set level idc. |
| </p> |
| </dd> |
| <dt><samp class="option">tier</samp></dt> |
| <dd><p>Set vvc tier. |
| </p> |
| </dd> |
| <dt><samp class="option">qp</samp></dt> |
| <dd><p>Set constant quantization parameter. |
| </p> |
| </dd> |
| <dt><samp class="option">subopt <var class="var">boolean</var></samp></dt> |
| <dd><p>Set subjective (perceptually motivated) optimization. Default is 1 (on). |
| </p> |
| </dd> |
| <dt><samp class="option">bitdepth8 <var class="var">boolean</var></samp></dt> |
| <dd><p>Set 8bit coding mode instead of using 10bit. Default is 0 (off). |
| </p> |
| </dd> |
| <dt><samp class="option">period</samp></dt> |
| <dd><p>set (intra) refresh period in seconds. |
| </p> |
| </dd> |
| <dt><samp class="option">vvenc-params</samp></dt> |
| <dd><p>Set vvenc options using a list of <var class="var">key</var>=<var class="var">value</var> couples separated |
| by ":". See <code class="command">vvencapp --fullhelp</code> or <code class="command">vvencFFapp --fullhelp</code> for a list of options. |
| </p> |
| <p>For example, the options might be provided as: |
| </p> |
| <div class="example"> |
| <pre class="example-preformatted">intraperiod=64:decodingrefreshtype=idr:poc0idr=1:internalbitdepth=8 |
| </pre></div> |
|
|
| <p>For example the encoding options might be provided with <samp class="option">-vvenc-params</samp>: |
| </p> |
| <div class="example"> |
| <pre class="example-preformatted">ffmpeg -i input -c:v libvvenc -b 1M -vvenc-params intraperiod=64:decodingrefreshtype=idr:poc0idr=1:internalbitdepth=8 output.mp4 |
| </pre></div> |
|
|
| </dd> |
| </dl> |
|
|
| <a name="libwebp"></a> |
| <h3 class="section">9.18 libwebp<span class="pull-right"><a class="anchor hidden-xs" href="#libwebp" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libwebp" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>libwebp WebP Image encoder wrapper |
| </p> |
| <p>libwebp is Google’s official encoder for WebP images. It can encode in either |
| lossy or lossless mode. Lossy images are essentially a wrapper around a VP8 |
| frame. Lossless images are a separate codec developed by Google. |
| </p> |
| <a name="Pixel-Format"></a> |
| <h4 class="subsection">9.18.1 Pixel Format<span class="pull-right"><a class="anchor hidden-xs" href="#Pixel-Format" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Pixel-Format" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>Currently, libwebp only supports YUV420 for lossy and RGB for lossless due |
| to limitations of the format and libwebp. Alpha is supported for either mode. |
| Because of API limitations, if RGB is passed in when encoding lossy or YUV is |
| passed in for encoding lossless, the pixel format will automatically be |
| converted using functions from libwebp. This is not ideal and is done only for |
| convenience. |
| </p> |
| <a name="Options-40"></a> |
| <h4 class="subsection">9.18.2 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-40" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-40" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">-lossless <var class="var">boolean</var></samp></dt> |
| <dd><p>Enables/Disables use of lossless mode. Default is 0. |
| </p> |
| </dd> |
| <dt><samp class="option">-compression_level <var class="var">integer</var></samp></dt> |
| <dd><p>For lossy, this is a quality/speed tradeoff. Higher values give better quality |
| for a given size at the cost of increased encoding time. For lossless, this is |
| a size/speed tradeoff. Higher values give smaller size at the cost of increased |
| encoding time. More specifically, it controls the number of extra algorithms |
| and compression tools used, and varies the combination of these tools. This |
| maps to the <var class="var">method</var> option in libwebp. The valid range is 0 to 6. |
| Default is 4. |
| </p> |
| </dd> |
| <dt><samp class="option">-quality <var class="var">float</var></samp></dt> |
| <dd><p>For lossy encoding, this controls image quality. For lossless encoding, this |
| controls the effort and time spent in compression. |
| Range is 0 to 100. Default is 75. |
| </p> |
| </dd> |
| <dt><samp class="option">-preset <var class="var">type</var></samp></dt> |
| <dd><p>Configuration preset. This does some automatic settings based on the general |
| type of the image. |
| </p><dl class="table"> |
| <dt><samp class="option">none</samp></dt> |
| <dd><p>Do not use a preset. |
| </p></dd> |
| <dt><samp class="option">default</samp></dt> |
| <dd><p>Use the encoder default. |
| </p></dd> |
| <dt><samp class="option">picture</samp></dt> |
| <dd><p>Digital picture, like portrait, inner shot |
| </p></dd> |
| <dt><samp class="option">photo</samp></dt> |
| <dd><p>Outdoor photograph, with natural lighting |
| </p></dd> |
| <dt><samp class="option">drawing</samp></dt> |
| <dd><p>Hand or line drawing, with high-contrast details |
| </p></dd> |
| <dt><samp class="option">icon</samp></dt> |
| <dd><p>Small-sized colorful images |
| </p></dd> |
| <dt><samp class="option">text</samp></dt> |
| <dd><p>Text-like |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
| <a name="libx264_002c-libx264rgb"></a> |
| <h3 class="section">9.19 libx264, libx264rgb<span class="pull-right"><a class="anchor hidden-xs" href="#libx264_002c-libx264rgb" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libx264_002c-libx264rgb" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>x264 H.264/MPEG-4 AVC encoder wrapper. |
| </p> |
| <p>This encoder requires the presence of the libx264 headers and library |
| during configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libx264</code>. |
| </p> |
| <p>libx264 supports an impressive number of features, including 8x8 and |
| 4x4 adaptive spatial transform, adaptive B-frame placement, CAVLC/CABAC |
| entropy coding, interlacing (MBAFF), lossless mode, psy optimizations |
| for detail retention (adaptive quantization, psy-RD, psy-trellis). |
| </p> |
| <p>Many libx264 encoder options are mapped to FFmpeg global codec |
| options, while unique encoder options are provided through private |
| options. Additionally the <samp class="option">x264opts</samp> and <samp class="option">x264-params</samp> |
| private options allows one to pass a list of key=value tuples as accepted |
| by the libx264 <code class="code">x264_param_parse</code> function. |
| </p> |
| <p>The x264 project website is at |
| <a class="url" href="http://www.videolan.org/developers/x264.html">http://www.videolan.org/developers/x264.html</a>. |
| </p> |
| <p>The libx264rgb encoder is the same as libx264, except it accepts packed RGB |
| pixel formats as input instead of YUV. |
| </p> |
| <a name="Supported-Pixel-Formats-1"></a> |
| <h4 class="subsection">9.19.1 Supported Pixel Formats<span class="pull-right"><a class="anchor hidden-xs" href="#Supported-Pixel-Formats-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Supported-Pixel-Formats-1" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>x264 supports 8- to 10-bit color spaces. The exact bit depth is controlled at |
| x264’s configure time. |
| </p> |
| <a name="Options-41"></a> |
| <h4 class="subsection">9.19.2 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-41" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-41" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following options are supported by the libx264 wrapper. The |
| <code class="command">x264</code>-equivalent options or values are listed in parentheses |
| for easy migration. |
| </p> |
| <p>To reduce the duplication of documentation, only the private options |
| and some others requiring special attention are documented here. For |
| the documentation of the undocumented generic options, see |
| <a class="ref" href="#codec_002doptions">the Codec Options chapter</a>. |
| </p> |
| <p>To get a more accurate and extensive documentation of the libx264 |
| options, invoke the command <code class="command">x264 --fullhelp</code> or consult |
| the libx264 documentation. |
| </p> |
| <p>In the list below, note that the <code class="command">x264</code> option name is shown |
| in parentheses after the libavcodec corresponding name, in case there |
| is a direct mapping. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">b (<em class="emph">bitrate</em>)</samp></dt> |
| <dd><p>Set bitrate in bits/s. Note that FFmpeg’s <samp class="option">b</samp> option is |
| expressed in bits/s, while <code class="command">x264</code>’s <samp class="option">bitrate</samp> is in |
| kilobits/s. |
| </p> |
| </dd> |
| <dt><samp class="option">bf (<em class="emph">bframes</em>)</samp></dt> |
| <dd><p>Number of B-frames between I and P-frames |
| </p> |
| </dd> |
| <dt><samp class="option">g (<em class="emph">keyint</em>)</samp></dt> |
| <dd><p>Maximum GOP size |
| </p> |
| </dd> |
| <dt><samp class="option">qmin (<em class="emph">qpmin</em>)</samp></dt> |
| <dd><p>Minimum quantizer scale |
| </p> |
| </dd> |
| <dt><samp class="option">qmax (<em class="emph">qpmax</em>)</samp></dt> |
| <dd><p>Maximum quantizer scale |
| </p> |
| </dd> |
| <dt><samp class="option">qdiff (<em class="emph">qpstep</em>)</samp></dt> |
| <dd><p>Maximum difference between quantizer scales |
| </p> |
| </dd> |
| <dt><samp class="option">qblur (<em class="emph">qblur</em>)</samp></dt> |
| <dd><p>Quantizer curve blur |
| </p> |
| </dd> |
| <dt><samp class="option">qcomp (<em class="emph">qcomp</em>)</samp></dt> |
| <dd><p>Quantizer curve compression factor |
| </p> |
| </dd> |
| <dt><samp class="option">refs (<em class="emph">ref</em>)</samp></dt> |
| <dd><p>Number of reference frames each P-frame can use. The range is <var class="var">0-16</var>. |
| </p> |
| </dd> |
| <dt><samp class="option">level (<em class="emph">level</em>)</samp></dt> |
| <dd><p>Set the <code class="code">x264_param_t.i_level_idc</code> value in case the value is |
| positive, it is ignored otherwise. |
| </p> |
| <p>This value can be set using the <code class="code">AVCodecContext</code> API (e.g. by |
| setting the <code class="code">AVCodecContext</code> value directly), and is specified as |
| an integer mapped on a corresponding level (e.g. the value 31 maps |
| to H.264 level IDC "3.1", as defined in the <code class="code">x264_levels</code> |
| table). It is ignored when set to a non positive value. |
| </p> |
| <p>Alternatively it can be set as a private option, overriding the value |
| set in <code class="code">AVCodecContext</code>, and in this case must be specified as |
| the level IDC identifier (e.g. "3.1"), as defined by H.264 Annex A. |
| </p> |
| </dd> |
| <dt><samp class="option">sc_threshold (<em class="emph">scenecut</em>)</samp></dt> |
| <dd><p>Sets the threshold for the scene change detection. |
| </p> |
| </dd> |
| <dt><samp class="option">trellis (<em class="emph">trellis</em>)</samp></dt> |
| <dd><p>Performs Trellis quantization to increase efficiency. Enabled by default. |
| </p> |
| </dd> |
| <dt><samp class="option">nr (<em class="emph">nr</em>)</samp></dt> |
| <dd><p>Noise reduction |
| </p> |
| </dd> |
| <dt><samp class="option">me_range (<em class="emph">merange</em>)</samp></dt> |
| <dd><p>Maximum range of the motion search in pixels. |
| </p> |
| </dd> |
| <dt><samp class="option">me_method (<em class="emph">me</em>)</samp></dt> |
| <dd><p>Set motion estimation method. Possible values in the decreasing order |
| of speed: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">dia (<em class="emph">dia</em>)</samp>’</dt> |
| <dt>‘<samp class="samp">epzs (<em class="emph">dia</em>)</samp>’</dt> |
| <dd><p>Diamond search with radius 1 (fastest). ‘<samp class="samp">epzs</samp>’ is an alias for |
| ‘<samp class="samp">dia</samp>’. |
| </p></dd> |
| <dt>‘<samp class="samp">hex (<em class="emph">hex</em>)</samp>’</dt> |
| <dd><p>Hexagonal search with radius 2. |
| </p></dd> |
| <dt>‘<samp class="samp">umh (<em class="emph">umh</em>)</samp>’</dt> |
| <dd><p>Uneven multi-hexagon search. |
| </p></dd> |
| <dt>‘<samp class="samp">esa (<em class="emph">esa</em>)</samp>’</dt> |
| <dd><p>Exhaustive search. |
| </p></dd> |
| <dt>‘<samp class="samp">tesa (<em class="emph">tesa</em>)</samp>’</dt> |
| <dd><p>Hadamard exhaustive search (slowest). |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">forced-idr</samp></dt> |
| <dd><p>Normally, when forcing a I-frame type, the encoder can select any type |
| of I-frame. This option forces it to choose an IDR-frame. |
| </p> |
| </dd> |
| <dt><samp class="option">subq (<em class="emph">subme</em>)</samp></dt> |
| <dd><p>Sub-pixel motion estimation method. |
| </p> |
| </dd> |
| <dt><samp class="option">b_strategy (<em class="emph">b-adapt</em>)</samp></dt> |
| <dd><p>Adaptive B-frame placement decision algorithm. Use only on first-pass. |
| </p> |
| </dd> |
| <dt><samp class="option">keyint_min (<em class="emph">min-keyint</em>)</samp></dt> |
| <dd><p>Minimum GOP size. |
| </p> |
| </dd> |
| <dt><samp class="option">coder</samp></dt> |
| <dd><p>Set entropy encoder. Possible values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">ac</samp>’</dt> |
| <dd><p>Enable CABAC. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">vlc</samp>’</dt> |
| <dd><p>Enable CAVLC and disable CABAC. It generates the same effect as |
| <code class="command">x264</code>’s <samp class="option">--no-cabac</samp> option. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">cmp</samp></dt> |
| <dd><p>Set full pixel motion estimation comparison algorithm. Possible values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">chroma</samp>’</dt> |
| <dd><p>Enable chroma in motion estimation. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">sad</samp>’</dt> |
| <dd><p>Ignore chroma in motion estimation. It generates the same effect as |
| <code class="command">x264</code>’s <samp class="option">--no-chroma-me</samp> option. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">threads (<em class="emph">threads</em>)</samp></dt> |
| <dd><p>Number of encoding threads. |
| </p> |
| </dd> |
| <dt><samp class="option">thread_type</samp></dt> |
| <dd><p>Set multithreading technique. Possible values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">slice</samp>’</dt> |
| <dd><p>Slice-based multithreading. It generates the same effect as |
| <code class="command">x264</code>’s <samp class="option">--sliced-threads</samp> option. |
| </p></dd> |
| <dt>‘<samp class="samp">frame</samp>’</dt> |
| <dd><p>Frame-based multithreading. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">flags</samp></dt> |
| <dd><p>Set encoding flags. It can be used to disable closed GOP and enable |
| open GOP by setting it to <code class="code">-cgop</code>. The result is similar to |
| the behavior of <code class="command">x264</code>’s <samp class="option">--open-gop</samp> option. |
| </p> |
| </dd> |
| <dt><samp class="option">rc_init_occupancy (<em class="emph">vbv-init</em>)</samp></dt> |
| <dd><p>Initial VBV buffer occupancy |
| </p> |
| </dd> |
| <dt><samp class="option">preset (<em class="emph">preset</em>)</samp></dt> |
| <dd><p>Set the encoding preset. |
| </p> |
| </dd> |
| <dt><samp class="option">tune (<em class="emph">tune</em>)</samp></dt> |
| <dd><p>Set tuning of the encoding params. |
| </p> |
| </dd> |
| <dt><samp class="option">profile (<em class="emph">profile</em>)</samp></dt> |
| <dd><p>Set profile restrictions. |
| </p> |
| </dd> |
| <dt><samp class="option">fastfirstpass</samp></dt> |
| <dd><p>Enable fast settings when encoding first pass, when set to 1. When set |
| to 0, it has the same effect of <code class="command">x264</code>’s |
| <samp class="option">--slow-firstpass</samp> option. |
| </p> |
| </dd> |
| <dt><samp class="option">crf (<em class="emph">crf</em>)</samp></dt> |
| <dd><p>Set the quality for constant quality mode. |
| </p> |
| </dd> |
| <dt><samp class="option">crf_max (<em class="emph">crf-max</em>)</samp></dt> |
| <dd><p>In CRF mode, prevents VBV from lowering quality beyond this point. |
| </p> |
| </dd> |
| <dt><samp class="option">qp (<em class="emph">qp</em>)</samp></dt> |
| <dd><p>Set constant quantization rate control method parameter. |
| </p> |
| </dd> |
| <dt><samp class="option">aq-mode (<em class="emph">aq-mode</em>)</samp></dt> |
| <dd><p>Set AQ method. Possible values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">none (<em class="emph">0</em>)</samp>’</dt> |
| <dd><p>Disabled. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">variance (<em class="emph">1</em>)</samp>’</dt> |
| <dd><p>Variance AQ (complexity mask). |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">autovariance (<em class="emph">2</em>)</samp>’</dt> |
| <dd><p>Auto-variance AQ (experimental). |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">aq-strength (<em class="emph">aq-strength</em>)</samp></dt> |
| <dd><p>Set AQ strength, reduce blocking and blurring in flat and textured areas. |
| </p> |
| </dd> |
| <dt><samp class="option">psy</samp></dt> |
| <dd><p>Use psychovisual optimizations when set to 1. When set to 0, it has the |
| same effect as <code class="command">x264</code>’s <samp class="option">--no-psy</samp> option. |
| </p> |
| </dd> |
| <dt><samp class="option">psy-rd (<em class="emph">psy-rd</em>)</samp></dt> |
| <dd><p>Set strength of psychovisual optimization, in |
| <var class="var">psy-rd</var>:<var class="var">psy-trellis</var> format. |
| </p> |
| </dd> |
| <dt><samp class="option">rc-lookahead (<em class="emph">rc-lookahead</em>)</samp></dt> |
| <dd><p>Set number of frames to look ahead for frametype and ratecontrol. |
| </p> |
| </dd> |
| <dt><samp class="option">weightb</samp></dt> |
| <dd><p>Enable weighted prediction for B-frames when set to 1. When set to 0, |
| it has the same effect as <code class="command">x264</code>’s <samp class="option">--no-weightb</samp> option. |
| </p> |
| </dd> |
| <dt><samp class="option">weightp (<em class="emph">weightp</em>)</samp></dt> |
| <dd><p>Set weighted prediction method for P-frames. Possible values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">none (<em class="emph">0</em>)</samp>’</dt> |
| <dd><p>Disabled |
| </p></dd> |
| <dt>‘<samp class="samp">simple (<em class="emph">1</em>)</samp>’</dt> |
| <dd><p>Enable only weighted refs |
| </p></dd> |
| <dt>‘<samp class="samp">smart (<em class="emph">2</em>)</samp>’</dt> |
| <dd><p>Enable both weighted refs and duplicates |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">ssim (<em class="emph">ssim</em>)</samp></dt> |
| <dd><p>Enable calculation and printing SSIM stats after the encoding. |
| </p> |
| </dd> |
| <dt><samp class="option">intra-refresh (<em class="emph">intra-refresh</em>)</samp></dt> |
| <dd><p>Enable the use of Periodic Intra Refresh instead of IDR frames when set |
| to 1. |
| </p> |
| </dd> |
| <dt><samp class="option">avcintra-class (<em class="emph">class</em>)</samp></dt> |
| <dd><p>Configure the encoder to generate AVC-Intra. |
| Valid values are 50, 100 and 200 |
| </p> |
| </dd> |
| <dt><samp class="option">bluray-compat (<em class="emph">bluray-compat</em>)</samp></dt> |
| <dd><p>Configure the encoder to be compatible with the bluray standard. |
| It is a shorthand for setting "bluray-compat=1 force-cfr=1". |
| </p> |
| </dd> |
| <dt><samp class="option">b-bias (<em class="emph">b-bias</em>)</samp></dt> |
| <dd><p>Set the influence on how often B-frames are used. |
| </p> |
| </dd> |
| <dt><samp class="option">b-pyramid (<em class="emph">b-pyramid</em>)</samp></dt> |
| <dd><p>Set method for keeping of some B-frames as references. Possible values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">none (<em class="emph">none</em>)</samp>’</dt> |
| <dd><p>Disabled. |
| </p></dd> |
| <dt>‘<samp class="samp">strict (<em class="emph">strict</em>)</samp>’</dt> |
| <dd><p>Strictly hierarchical pyramid. |
| </p></dd> |
| <dt>‘<samp class="samp">normal (<em class="emph">normal</em>)</samp>’</dt> |
| <dd><p>Non-strict (not Blu-ray compatible). |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">mixed-refs</samp></dt> |
| <dd><p>Enable the use of one reference per partition, as opposed to one |
| reference per macroblock when set to 1. When set to 0, it has the |
| same effect as <code class="command">x264</code>’s <samp class="option">--no-mixed-refs</samp> option. |
| </p> |
| </dd> |
| <dt><samp class="option">8x8dct</samp></dt> |
| <dd><p>Enable adaptive spatial transform (high profile 8x8 transform) |
| when set to 1. When set to 0, it has the same effect as |
| <code class="command">x264</code>’s <samp class="option">--no-8x8dct</samp> option. |
| </p> |
| </dd> |
| <dt><samp class="option">fast-pskip</samp></dt> |
| <dd><p>Enable early SKIP detection on P-frames when set to 1. When set |
| to 0, it has the same effect as <code class="command">x264</code>’s |
| <samp class="option">--no-fast-pskip</samp> option. |
| </p> |
| </dd> |
| <dt><samp class="option">aud (<em class="emph">aud</em>)</samp></dt> |
| <dd><p>Enable use of access unit delimiters when set to 1. |
| </p> |
| </dd> |
| <dt><samp class="option">mbtree</samp></dt> |
| <dd><p>Enable use macroblock tree ratecontrol when set to 1. When set |
| to 0, it has the same effect as <code class="command">x264</code>’s |
| <samp class="option">--no-mbtree</samp> option. |
| </p> |
| </dd> |
| <dt><samp class="option">deblock (<em class="emph">deblock</em>)</samp></dt> |
| <dd><p>Set loop filter parameters, in <var class="var">alpha</var>:<var class="var">beta</var> form. |
| </p> |
| </dd> |
| <dt><samp class="option">cplxblur (<em class="emph">cplxblur</em>)</samp></dt> |
| <dd><p>Set fluctuations reduction in QP (before curve compression). |
| </p> |
| </dd> |
| <dt><samp class="option">partitions (<em class="emph">partitions</em>)</samp></dt> |
| <dd><p>Set partitions to consider as a comma-separated list of values. |
| Possible values in the list: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">p8x8</samp>’</dt> |
| <dd><p>8x8 P-frame partition. |
| </p></dd> |
| <dt>‘<samp class="samp">p4x4</samp>’</dt> |
| <dd><p>4x4 P-frame partition. |
| </p></dd> |
| <dt>‘<samp class="samp">b8x8</samp>’</dt> |
| <dd><p>4x4 B-frame partition. |
| </p></dd> |
| <dt>‘<samp class="samp">i8x8</samp>’</dt> |
| <dd><p>8x8 I-frame partition. |
| </p></dd> |
| <dt>‘<samp class="samp">i4x4</samp>’</dt> |
| <dd><p>4x4 I-frame partition. |
| (Enabling ‘<samp class="samp">p4x4</samp>’ requires ‘<samp class="samp">p8x8</samp>’ to be enabled. Enabling |
| ‘<samp class="samp">i8x8</samp>’ requires adaptive spatial transform (<samp class="option">8x8dct</samp> |
| option) to be enabled.) |
| </p></dd> |
| <dt>‘<samp class="samp">none (<em class="emph">none</em>)</samp>’</dt> |
| <dd><p>Do not consider any partitions. |
| </p></dd> |
| <dt>‘<samp class="samp">all (<em class="emph">all</em>)</samp>’</dt> |
| <dd><p>Consider every partition. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">direct-pred (<em class="emph">direct</em>)</samp></dt> |
| <dd><p>Set direct MV prediction mode. Possible values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">none (<em class="emph">none</em>)</samp>’</dt> |
| <dd><p>Disable MV prediction. |
| </p></dd> |
| <dt>‘<samp class="samp">spatial (<em class="emph">spatial</em>)</samp>’</dt> |
| <dd><p>Enable spatial predicting. |
| </p></dd> |
| <dt>‘<samp class="samp">temporal (<em class="emph">temporal</em>)</samp>’</dt> |
| <dd><p>Enable temporal predicting. |
| </p></dd> |
| <dt>‘<samp class="samp">auto (<em class="emph">auto</em>)</samp>’</dt> |
| <dd><p>Automatically decided. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">slice-max-size (<em class="emph">slice-max-size</em>)</samp></dt> |
| <dd><p>Set the limit of the size of each slice in bytes. If not specified |
| but RTP payload size (<samp class="option">ps</samp>) is specified, that is used. |
| </p> |
| </dd> |
| <dt><samp class="option">stats (<em class="emph">stats</em>)</samp></dt> |
| <dd><p>Set the file name for multi-pass stats. |
| </p> |
| </dd> |
| <dt><samp class="option">nal-hrd (<em class="emph">nal-hrd</em>)</samp></dt> |
| <dd><p>Set signal HRD information (requires <samp class="option">vbv-bufsize</samp> to be set). |
| Possible values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">none (<em class="emph">none</em>)</samp>’</dt> |
| <dd><p>Disable HRD information signaling. |
| </p></dd> |
| <dt>‘<samp class="samp">vbr (<em class="emph">vbr</em>)</samp>’</dt> |
| <dd><p>Variable bit rate. |
| </p></dd> |
| <dt>‘<samp class="samp">cbr (<em class="emph">cbr</em>)</samp>’</dt> |
| <dd><p>Constant bit rate (not allowed in MP4 container). |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">x264opts <var class="var">opts</var></samp></dt> |
| <dt><samp class="option">x264-params <var class="var">opts</var></samp></dt> |
| <dd><p>Override the x264 configuration using a :-separated list of key=value |
| options. |
| </p> |
| <p>The argument for both options is a list of <var class="var">key</var>=<var class="var">value</var> |
| couples separated by ":". With <samp class="option">x264opts</samp> the value can be |
| omitted, and the value <code class="code">1</code> is assumed in that case. |
| </p> |
| <p>For <var class="var">filter</var> and <var class="var">psy-rd</var> options values that use ":" as a |
| separator themselves, use "," instead. They accept it as well since |
| long ago but this is kept undocumented for some reason. |
| </p> |
| <p>For example, the options might be provided as: |
| </p><div class="example"> |
| <pre class="example-preformatted">level=30:bframes=0:weightp=0:cabac=0:ref=1:vbv-maxrate=768:vbv-bufsize=2000:analyse=all:me=umh:no-fast-pskip=1:subq=6:8x8dct=0:trellis=0 |
| </pre></div> |
|
|
| <p>For example to specify libx264 encoding options with <code class="command">ffmpeg</code>: |
| </p><div class="example"> |
| <pre class="example-preformatted">ffmpeg -i foo.mpg -c:v libx264 -x264opts keyint=123:min-keyint=20 -an out.mkv |
| </pre></div> |
|
|
| <p>To get the complete list of the libx264 options, invoke the command |
| <code class="command">x264 --fullhelp</code> or consult the libx264 documentation. |
| </p> |
| </dd> |
| <dt><samp class="option">a53cc <var class="var">boolean</var></samp></dt> |
| <dd><p>Import closed captions (which must be ATSC compatible format) into output. |
| Only the mpeg2 and h264 decoders provide these. Default is 1 (on). |
| </p> |
| </dd> |
| <dt><samp class="option">udu_sei <var class="var">boolean</var></samp></dt> |
| <dd><p>Import user data unregistered SEI if available into output. Default is 0 (off). |
| </p> |
| </dd> |
| <dt><samp class="option">mb_info <var class="var">boolean</var></samp></dt> |
| <dd><p>Set mb_info data through AVFrameSideData, only useful when used from the |
| API. Default is 0 (off). |
| </p></dd> |
| </dl> |
|
|
| <p>Encoding ffpresets for common usages are provided so they can be used with the |
| general presets system (e.g. passing the <samp class="option">pre</samp> option). |
| </p> |
| <a name="libx265"></a> |
| <h3 class="section">9.20 libx265<span class="pull-right"><a class="anchor hidden-xs" href="#libx265" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libx265" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>x265 H.265/HEVC encoder wrapper. |
| </p> |
| <p>This encoder requires the presence of the libx265 headers and library |
| during configuration. You need to explicitly configure the build with |
| <samp class="option">--enable-libx265</samp>. |
| </p> |
| <a name="Options-42"></a> |
| <h4 class="subsection">9.20.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-42" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-42" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">b</samp></dt> |
| <dd><p>Sets target video bitrate. |
| </p> |
| </dd> |
| <dt><samp class="option">bf</samp></dt> |
| <dt><samp class="option">g</samp></dt> |
| <dd><p>Set the GOP size. |
| </p> |
| </dd> |
| <dt><samp class="option">keyint_min</samp></dt> |
| <dd><p>Minimum GOP size. |
| </p> |
| </dd> |
| <dt><samp class="option">refs</samp></dt> |
| <dd><p>Number of reference frames each P-frame can use. The range is from <var class="var">1-16</var>. |
| </p> |
| </dd> |
| <dt><samp class="option">preset</samp></dt> |
| <dd><p>Set the x265 preset. |
| </p> |
| </dd> |
| <dt><samp class="option">tune</samp></dt> |
| <dd><p>Set the x265 tune parameter. |
| </p> |
| </dd> |
| <dt><samp class="option">profile</samp></dt> |
| <dd><p>Set profile restrictions. |
| </p> |
| </dd> |
| <dt><samp class="option">crf</samp></dt> |
| <dd><p>Set the quality for constant quality mode. |
| </p> |
| </dd> |
| <dt><samp class="option">qp</samp></dt> |
| <dd><p>Set constant quantization rate control method parameter. |
| </p> |
| </dd> |
| <dt><samp class="option">qmin</samp></dt> |
| <dd><p>Minimum quantizer scale. |
| </p> |
| </dd> |
| <dt><samp class="option">qmax</samp></dt> |
| <dd><p>Maximum quantizer scale. |
| </p> |
| </dd> |
| <dt><samp class="option">qdiff</samp></dt> |
| <dd><p>Maximum difference between quantizer scales. |
| </p> |
| </dd> |
| <dt><samp class="option">qblur</samp></dt> |
| <dd><p>Quantizer curve blur |
| </p> |
| </dd> |
| <dt><samp class="option">qcomp</samp></dt> |
| <dd><p>Quantizer curve compression factor |
| </p> |
| </dd> |
| <dt><samp class="option">i_qfactor</samp></dt> |
| <dt><samp class="option">b_qfactor</samp></dt> |
| <dt><samp class="option">forced-idr</samp></dt> |
| <dd><p>Normally, when forcing a I-frame type, the encoder can select any type |
| of I-frame. This option forces it to choose an IDR-frame. |
| </p> |
| </dd> |
| <dt><samp class="option">x265-stats</samp></dt> |
| <dd><p>Specify the file name for 2-pass stats. This is set automatically when using |
| the <samp class="option">-passlogfile</samp> option. |
| </p> |
| </dd> |
| <dt><samp class="option">udu_sei <var class="var">boolean</var></samp></dt> |
| <dd><p>Import user data unregistered SEI if available into output. Default is 0 (off). |
| </p> |
| </dd> |
| <dt><samp class="option">x265-params</samp></dt> |
| <dd><p>Set x265 options using a list of <var class="var">key</var>=<var class="var">value</var> couples separated |
| by ":". See <code class="command">x265 --help</code> for a list of options. |
| </p> |
| <p>For example to specify libx265 encoding options with <samp class="option">-x265-params</samp>: |
| </p> |
| <div class="example"> |
| <pre class="example-preformatted">ffmpeg -i input -c:v libx265 -x265-params crf=26:psy-rd=1 output.mp4 |
| </pre></div> |
| </dd> |
| </dl> |
|
|
| <a name="libxavs2"></a> |
| <h3 class="section">9.21 libxavs2<span class="pull-right"><a class="anchor hidden-xs" href="#libxavs2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libxavs2" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>xavs2 AVS2-P2/IEEE1857.4 encoder wrapper. |
| </p> |
| <p>This encoder requires the presence of the libxavs2 headers and library |
| during configuration. You need to explicitly configure the build with |
| <samp class="option">--enable-libxavs2</samp>. |
| </p> |
| <p>The following standard libavcodec options are used: |
| </p><ul class="itemize mark-bullet"> |
| <li><samp class="option">b</samp> / <samp class="option">bit_rate</samp> |
| </li><li><samp class="option">g</samp> / <samp class="option">gop_size</samp> |
| </li><li><samp class="option">bf</samp> / <samp class="option">max_b_frames</samp> |
| </li></ul> |
|
|
| <p>The encoder also has its own specific options: |
| </p><a name="Options-43"></a> |
| <h4 class="subsection">9.21.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-43" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-43" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">lcu_row_threads</samp></dt> |
| <dd><p>Set the number of parallel threads for rows from 1 to 8 (default 5). |
| </p> |
| </dd> |
| <dt><samp class="option">initial_qp</samp></dt> |
| <dd><p>Set the xavs2 quantization parameter from 1 to 63 (default 34). This is |
| used to set the initial qp for the first frame. |
| </p> |
| </dd> |
| <dt><samp class="option">qp</samp></dt> |
| <dd><p>Set the xavs2 quantization parameter from 1 to 63 (default 34). This is |
| used to set the qp value under constant-QP mode. |
| </p> |
| </dd> |
| <dt><samp class="option">max_qp</samp></dt> |
| <dd><p>Set the max qp for rate control from 1 to 63 (default 55). |
| </p> |
| </dd> |
| <dt><samp class="option">min_qp</samp></dt> |
| <dd><p>Set the min qp for rate control from 1 to 63 (default 20). |
| </p> |
| </dd> |
| <dt><samp class="option">speed_level</samp></dt> |
| <dd><p>Set the Speed level from 0 to 9 (default 0). Higher is better but slower. |
| </p> |
| </dd> |
| <dt><samp class="option">log_level</samp></dt> |
| <dd><p>Set the log level from -1 to 3 (default 0). -1: none, 0: error, |
| 1: warning, 2: info, 3: debug. |
| </p> |
| </dd> |
| <dt><samp class="option">xavs2-params</samp></dt> |
| <dd><p>Set xavs2 options using a list of <var class="var">key</var>=<var class="var">value</var> couples separated |
| by ":". |
| </p> |
| <p>For example to specify libxavs2 encoding options with <samp class="option">-xavs2-params</samp>: |
| </p> |
| <div class="example"> |
| <pre class="example-preformatted">ffmpeg -i input -c:v libxavs2 -xavs2-params RdoqLevel=0 output.avs2 |
| </pre></div> |
| </dd> |
| </dl> |
|
|
| <a name="libxeve"></a> |
| <h3 class="section">9.22 libxeve<span class="pull-right"><a class="anchor hidden-xs" href="#libxeve" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libxeve" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>eXtra-fast Essential Video Encoder (XEVE) MPEG-5 EVC encoder wrapper. |
| The xeve-equivalent options or values are listed in parentheses for easy migration. |
| </p> |
| <p>This encoder requires the presence of the libxeve headers and library |
| during configuration. You need to explicitly configure the build with |
| <samp class="option">--enable-libxeve</samp>. |
| </p> |
| <div class="info"> |
| <p>Many libxeve encoder options are mapped to FFmpeg global codec options, |
| while unique encoder options are provided through private options. |
| Additionally the xeve-params private options allows one to pass a list |
| of key=value tuples as accepted by the libxeve <code class="code">parse_xeve_params</code> function. |
| </p></div> |
| <p>The xeve project website is at <a class="url" href="https://github.com/mpeg5/xeve">https://github.com/mpeg5/xeve</a>. |
| </p> |
| <a name="Options-44"></a> |
| <h4 class="subsection">9.22.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-44" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-44" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following options are supported by the libxeve wrapper. |
| The xeve-equivalent options or values are listed in parentheses for easy migration. |
| </p> |
| <div class="info"> |
| <p>To reduce the duplication of documentation, only the private options |
| and some others requiring special attention are documented here. For |
| the documentation of the undocumented generic options, see |
| <a class="ref" href="#codec_002doptions">the Codec Options chapter</a>. |
| </p></div> |
| <div class="info"> |
| <p>To get a more accurate and extensive documentation of the libxeve options, |
| invoke the command <code class="code">xeve_app --help</code> or consult the libxeve documentation. |
| </p></div> |
| <dl class="table"> |
| <dt><samp class="option">b (<em class="emph">bitrate</em>)</samp></dt> |
| <dd><p>Set target video bitrate in bits/s. |
| Note that FFmpeg’s b option is expressed in bits/s, while xeve’s bitrate is in kilobits/s. |
| </p> |
| </dd> |
| <dt><samp class="option">bf (<em class="emph">bframes</em>)</samp></dt> |
| <dd><p>Set the maximum number of B frames (1,3,7,15). |
| </p> |
| </dd> |
| <dt><samp class="option">g (<em class="emph">keyint</em>)</samp></dt> |
| <dd><p>Set the GOP size (I-picture period). |
| </p> |
| </dd> |
| <dt><samp class="option">preset (<em class="emph">preset</em>)</samp></dt> |
| <dd><p>Set the xeve preset. |
| Set the encoder preset value to determine encoding speed [fast, medium, slow, placebo] |
| </p> |
| </dd> |
| <dt><samp class="option">tune (<em class="emph">tune</em>)</samp></dt> |
| <dd><p>Set the encoder tune parameter [psnr, zerolatency] |
| </p> |
| </dd> |
| <dt><samp class="option">profile (<em class="emph">profile</em>)</samp></dt> |
| <dd><p>Set the encoder profile [0: baseline; 1: main] |
| </p> |
| </dd> |
| <dt><samp class="option">crf (<em class="emph">crf</em>)</samp></dt> |
| <dd><p>Set the quality for constant quality mode. |
| Constant rate factor <10..49> [default: 32] |
| </p> |
| </dd> |
| <dt><samp class="option">qp (<em class="emph">qp</em>)</samp></dt> |
| <dd><p>Set constant quantization rate control method parameter. |
| Quantization parameter qp <0..51> [default: 32] |
| </p> |
| </dd> |
| <dt><samp class="option">threads (<em class="emph">threads</em>)</samp></dt> |
| <dd><p>Force to use a specific number of threads |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="libxvid"></a> |
| <h3 class="section">9.23 libxvid<span class="pull-right"><a class="anchor hidden-xs" href="#libxvid" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-libxvid" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Xvid MPEG-4 Part 2 encoder wrapper. |
| </p> |
| <p>This encoder requires the presence of the libxvidcore headers and library |
| during configuration. You need to explicitly configure the build with |
| <code class="code">--enable-libxvid --enable-gpl</code>. |
| </p> |
| <p>The native <code class="code">mpeg4</code> encoder supports the MPEG-4 Part 2 format, so |
| users can encode to this format without this library. |
| </p> |
| <a name="Options-45"></a> |
| <h4 class="subsection">9.23.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-45" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-45" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>The following options are supported by the libxvid wrapper. Some of |
| the following options are listed but are not documented, and |
| correspond to shared codec options. See <a class="ref" href="#codec_002doptions">the Codec |
| Options chapter</a> for their documentation. The other shared options |
| which are not listed have no effect for the libxvid encoder. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">b</samp></dt> |
| <dt><samp class="option">g</samp></dt> |
| <dt><samp class="option">qmin</samp></dt> |
| <dt><samp class="option">qmax</samp></dt> |
| <dt><samp class="option">mpeg_quant</samp></dt> |
| <dt><samp class="option">threads</samp></dt> |
| <dt><samp class="option">bf</samp></dt> |
| <dt><samp class="option">b_qfactor</samp></dt> |
| <dt><samp class="option">b_qoffset</samp></dt> |
| <dt><samp class="option">flags</samp></dt> |
| <dd><p>Set specific encoding flags. Possible values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">mv4</samp>’</dt> |
| <dd><p>Use four motion vector by macroblock. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">aic</samp>’</dt> |
| <dd><p>Enable high quality AC prediction. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">gray</samp>’</dt> |
| <dd><p>Only encode grayscale. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">qpel</samp>’</dt> |
| <dd><p>Enable quarter-pixel motion compensation. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">cgop</samp>’</dt> |
| <dd><p>Enable closed GOP. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">global_header</samp>’</dt> |
| <dd><p>Place global headers in extradata instead of every keyframe. |
| </p> |
| </dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">gmc</samp></dt> |
| <dd><p>Enable the use of global motion compensation (GMC). Default is 0 |
| (disabled). |
| </p> |
| </dd> |
| <dt><samp class="option">me_quality</samp></dt> |
| <dd><p>Set motion estimation quality level. Possible values in decreasing order of |
| speed and increasing order of quality: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">0</samp>’</dt> |
| <dd><p>Use no motion estimation (default). |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">1, 2</samp>’</dt> |
| <dd><p>Enable advanced diamond zonal search for 16x16 blocks and half-pixel |
| refinement for 16x16 blocks. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">3, 4</samp>’</dt> |
| <dd><p>Enable all of the things described above, plus advanced diamond zonal |
| search for 8x8 blocks and half-pixel refinement for 8x8 blocks, also |
| enable motion estimation on chroma planes for P and B-frames. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">5, 6</samp>’</dt> |
| <dd><p>Enable all of the things described above, plus extended 16x16 and 8x8 |
| blocks search. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">mbd</samp></dt> |
| <dd><p>Set macroblock decision algorithm. Possible values in the increasing |
| order of quality: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">simple</samp>’</dt> |
| <dd><p>Use macroblock comparing function algorithm (default). |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">bits</samp>’</dt> |
| <dd><p>Enable rate distortion-based half pixel and quarter pixel refinement for |
| 16x16 blocks. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">rd</samp>’</dt> |
| <dd><p>Enable all of the things described above, plus rate distortion-based |
| half pixel and quarter pixel refinement for 8x8 blocks, and rate |
| distortion-based search using square pattern. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">lumi_aq</samp></dt> |
| <dd><p>Enable lumi masking adaptive quantization when set to 1. Default is 0 |
| (disabled). |
| </p> |
| </dd> |
| <dt><samp class="option">variance_aq</samp></dt> |
| <dd><p>Enable variance adaptive quantization when set to 1. Default is 0 |
| (disabled). |
| </p> |
| <p>When combined with <samp class="option">lumi_aq</samp>, the resulting quality will not |
| be better than any of the two specified individually. In other |
| words, the resulting quality will be the worse one of the two |
| effects. |
| </p> |
| </dd> |
| <dt><samp class="option">trellis</samp></dt> |
| <dd><p>Set rate-distortion optimal quantization. |
| </p> |
| </dd> |
| <dt><samp class="option">ssim</samp></dt> |
| <dd><p>Set structural similarity (SSIM) displaying method. Possible values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">off</samp>’</dt> |
| <dd><p>Disable displaying of SSIM information. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">avg</samp>’</dt> |
| <dd><p>Output average SSIM at the end of encoding to stdout. The format of |
| showing the average SSIM is: |
| </p> |
| <div class="example"> |
| <pre class="example-preformatted">Average SSIM: %f |
| </pre></div> |
|
|
| <p>For users who are not familiar with C, %f means a float number, or |
| a decimal (e.g. 0.939232). |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">frame</samp>’</dt> |
| <dd><p>Output both per-frame SSIM data during encoding and average SSIM at |
| the end of encoding to stdout. The format of per-frame information |
| is: |
| </p> |
| <div class="example"> |
| <pre class="example-preformatted"> SSIM: avg: %1.3f min: %1.3f max: %1.3f |
| </pre></div> |
|
|
| <p>For users who are not familiar with C, %1.3f means a float number |
| rounded to 3 digits after the dot (e.g. 0.932). |
| </p> |
| </dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">ssim_acc</samp></dt> |
| <dd><p>Set SSIM accuracy. Valid options are integers within the range of |
| 0-4, while 0 gives the most accurate result and 4 computes the |
| fastest. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="MediaCodec"></a> |
| <h3 class="section">9.24 MediaCodec<span class="pull-right"><a class="anchor hidden-xs" href="#MediaCodec" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-MediaCodec" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>MediaCodec encoder wrapper enables hardware-accelerated video encoding on |
| Android device. It supports H.264, H.265 (HEVC), VP8, VP9, MPEG-4, and AV1 |
| encoding (whether works or not is device dependent). |
| </p> |
| <p>Android provides two sets of APIs: Java MediaCodec and NDK MediaCodec. The |
| MediaCodec encoder wrapper supports both. Note that the NDK MediaCodec API |
| operates without requiring JVM, but may fail to function outside the JVM |
| environment due to dependencies on system framework services, particularly |
| after Android 15. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">ndk_codec <var class="var">boolean</var></samp></dt> |
| <dd><p>Use the NDK-based MediaCodec API instead of the Java API. Enabled by default |
| if <code class="code">av_jni_get_java_vm()</code> return NULL. |
| </p> |
| </dd> |
| <dt><samp class="option">ndk_async <var class="var">boolean</var></samp></dt> |
| <dd><p>Use NDK MediaCodec in async mode. Async mode has less overhead than poll in a |
| loop in sync mode. The drawback of async mode is AV_CODEC_FLAG_GLOBAL_HEADER |
| doesn’t work (use extract_extradata bsf when necessary). It doesn’t work and |
| will be disabled automatically on devices below Android 8.0. |
| </p> |
| </dd> |
| <dt><samp class="option">codec_name <var class="var">string</var></samp></dt> |
| <dd><p>A codec type can have multiple implementations on a single device, this option |
| specify which backend to use (via MediaCodec createCodecByName API). It’s NULL |
| by default, and encoder is created by createEncoderByType. |
| </p> |
| </dd> |
| <dt><samp class="option">bitrate_mode <var class="var">integer</var></samp></dt> |
| <dd> |
| <p>Possible values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">cq</samp>’</dt> |
| <dd><p>Constant quality mode |
| </p></dd> |
| <dt>‘<samp class="samp">vbr</samp>’</dt> |
| <dd><p>Variable bitrate mode |
| </p></dd> |
| <dt>‘<samp class="samp">cbr</samp>’</dt> |
| <dd><p>Constant bitrate mode |
| </p></dd> |
| <dt>‘<samp class="samp">cbr_fd</samp>’</dt> |
| <dd><p>Constant bitrate mode with frame drops |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">pts_as_dts <var class="var">boolean</var></samp></dt> |
| <dd><p>Use PTS as DTS. This is a workaround since MediaCodec API doesn’t provide |
| decoding timestamp. It is enabled automatically if B frame is 0. |
| </p> |
| </dd> |
| <dt><samp class="option">operating_rate <var class="var">integer</var></samp></dt> |
| <dd><p>The desired operating rate that the codec will need to operate at, zero for |
| unspecified. This is used for cases like high-speed/slow-motion video capture, |
| where the video encoder format contains the target playback rate (e.g. 30fps), |
| but the component must be able to handle the high operating capture rate (e.g. |
| 240fps). This rate will be used by codec for resource planning and setting the |
| operating points. |
| </p> |
| </dd> |
| <dt><samp class="option">qp_i_min <var class="var">integer</var></samp></dt> |
| <dd><p>Minimum quantization parameter for I frame. |
| </p></dd> |
| <dt><samp class="option">qp_p_min <var class="var">integer</var></samp></dt> |
| <dd><p>Minimum quantization parameter for P frame. |
| </p></dd> |
| <dt><samp class="option">qp_b_min <var class="var">integer</var></samp></dt> |
| <dd><p>Minimum quantization parameter for B frame. |
| </p></dd> |
| <dt><samp class="option">qp_i_max <var class="var">integer</var></samp></dt> |
| <dd><p>Maximum quantization parameter for I frame. |
| </p></dd> |
| <dt><samp class="option">qp_p_max <var class="var">integer</var></samp></dt> |
| <dd><p>Maximum quantization parameter for P frame. |
| </p></dd> |
| <dt><samp class="option">qp_b_max <var class="var">integer</var></samp></dt> |
| <dd><p>Maximum quantization parameter for B frame. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="MediaFoundation"></a> |
| <h3 class="section">9.25 MediaFoundation<span class="pull-right"><a class="anchor hidden-xs" href="#MediaFoundation" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-MediaFoundation" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>The following wrappers for encoders in the MediaFoundation framework are |
| available: |
| </p> |
| <ul class="itemize mark-bullet"> |
| <li>h264_mf |
| </li><li>hevc_mf |
| </li><li>av1_mf |
| </li></ul> |
|
|
| <p>These support both software and hardware encoding. |
| </p> |
| <p>Video encoders can take input in either of nv12 or yuv420p form |
| (some encoders support both, some support only either - in practice, |
| nv12 is the safer choice, especially among HW encoders). |
| </p> |
| <p>Hardware-accelerated encoding requires D3D11, including hardware |
| scaling capabilities through the scale_d3d11 filter. |
| </p> |
| <p>To list all available options for the MediaFoundation encoders, use: |
| <code class="command">ffmpeg -h encoder=<encoder></code> e.g. <code class="command">ffmpeg -h encoder=h264_mf</code> |
| </p> |
| <a name="Options-46"></a> |
| <h4 class="subsection">9.25.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-46" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-46" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">rate_control</samp></dt> |
| <dd><p>Select rate control mode. Available modes: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">default</samp>’</dt> |
| <dd><p>Default mode |
| </p></dd> |
| <dt>‘<samp class="samp">cbr</samp>’</dt> |
| <dd><p>CBR mode |
| </p></dd> |
| <dt>‘<samp class="samp">pc_vbr</samp>’</dt> |
| <dd><p>Peak constrained VBR mode |
| </p></dd> |
| <dt>‘<samp class="samp">u_vbr</samp>’</dt> |
| <dd><p>Unconstrained VBR mode |
| </p></dd> |
| <dt>‘<samp class="samp">quality</samp>’</dt> |
| <dd><p>Quality mode |
| </p></dd> |
| <dt>‘<samp class="samp">ld_vbr</samp>’</dt> |
| <dd><p>Low delay VBR mode (requires Windows 8+) |
| </p></dd> |
| <dt>‘<samp class="samp">g_vbr</samp>’</dt> |
| <dd><p>Global VBR mode (requires Windows 8+) |
| </p></dd> |
| <dt>‘<samp class="samp">gld_vbr</samp>’</dt> |
| <dd><p>Global low delay VBR mode (requires Windows 8+) |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">scenario</samp></dt> |
| <dd><p>Select usage scenario. Available scenarios: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">default</samp>’</dt> |
| <dd><p>Default scenario |
| </p></dd> |
| <dt>‘<samp class="samp">display_remoting</samp>’</dt> |
| <dd><p>Display remoting scenario |
| </p></dd> |
| <dt>‘<samp class="samp">video_conference</samp>’</dt> |
| <dd><p>Video conference scenario |
| </p></dd> |
| <dt>‘<samp class="samp">archive</samp>’</dt> |
| <dd><p>Archive scenario |
| </p></dd> |
| <dt>‘<samp class="samp">live_streaming</samp>’</dt> |
| <dd><p>Live streaming scenario |
| </p></dd> |
| <dt>‘<samp class="samp">camera_record</samp>’</dt> |
| <dd><p>Camera record scenario |
| </p></dd> |
| <dt>‘<samp class="samp">display_remoting_with_feature_map</samp>’</dt> |
| <dd><p>Display remoting with feature map scenario |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">quality</samp></dt> |
| <dd><p>Set encoding quality (0-100). -1 means default quality. |
| </p> |
| </dd> |
| <dt><samp class="option">hw_encoding</samp></dt> |
| <dd><p>Force hardware encoding (0-1). Default is 0 (disabled). |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="Examples-2"></a> |
| <h4 class="subsection">9.25.2 Examples<span class="pull-right"><a class="anchor hidden-xs" href="#Examples-2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Examples-2" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>Hardware encoding: |
| </p><div class="example"> |
| <pre class="example-preformatted">ffmpeg -i input.mp4 -c:v h264_mf -hw_encoding 1 output.mp4 |
| </pre></div> |
|
|
| <p>Hardware-accelerated decoding with hardware encoding: |
| </p><div class="example"> |
| <pre class="example-preformatted">ffmpeg -hwaccel d3d11va -i input.mp4 -c:v h264_mf -hw_encoding 1 output.mp4 |
| </pre></div> |
|
|
| <p>Hardware-accelerated decoding, HW scaling and encoding with quality setting: |
| </p><div class="example"> |
| <pre class="example-preformatted">ffmpeg -hwaccel d3d11va -hwaccel_output_format d3d11 -i input.mp4 -vf scale_d3d11=1920:1080 -c:v hevc_mf -hw_encoding 1 -quality 80 output.mp4 |
| </pre></div> |
|
|
| <a name="Microsoft-RLE"></a> |
| <h3 class="section">9.26 Microsoft RLE<span class="pull-right"><a class="anchor hidden-xs" href="#Microsoft-RLE" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Microsoft-RLE" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Microsoft RLE aka MSRLE encoder. |
| Only 8-bit palette mode supported. |
| Compatible with Windows 3.1 and Windows 95. |
| </p> |
| <a name="Options-47"></a> |
| <h4 class="subsection">9.26.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-47" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-47" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">g <var class="var">integer</var></samp></dt> |
| <dd><p>Keyframe interval. |
| A keyframe is inserted at least every <code class="code">-g</code> frames, sometimes sooner. |
| </p></dd> |
| </dl> |
|
|
| <a name="mpeg2"></a> |
| <h3 class="section">9.27 mpeg2<span class="pull-right"><a class="anchor hidden-xs" href="#mpeg2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-mpeg2" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>MPEG-2 video encoder. |
| </p> |
| <a name="Options-48"></a> |
| <h4 class="subsection">9.27.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-48" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-48" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">profile</samp></dt> |
| <dd><p>Select the mpeg2 profile to encode: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">422</samp>’</dt> |
| <dt>‘<samp class="samp">high</samp>’</dt> |
| <dt>‘<samp class="samp">ss</samp>’</dt> |
| <dd><p>Spatially Scalable |
| </p></dd> |
| <dt>‘<samp class="samp">snr</samp>’</dt> |
| <dd><p>SNR Scalable |
| </p></dd> |
| <dt>‘<samp class="samp">main</samp>’</dt> |
| <dt>‘<samp class="samp">simple</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">level</samp></dt> |
| <dd><p>Select the mpeg2 level to encode: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">high</samp>’</dt> |
| <dt>‘<samp class="samp">high1440</samp>’</dt> |
| <dt>‘<samp class="samp">main</samp>’</dt> |
| <dt>‘<samp class="samp">low</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">seq_disp_ext <var class="var">integer</var></samp></dt> |
| <dd><p>Specifies if the encoder should write a sequence_display_extension to the |
| output. |
| </p><dl class="table"> |
| <dt><samp class="option">-1</samp></dt> |
| <dt><samp class="option">auto</samp></dt> |
| <dd><p>Decide automatically to write it or not (this is the default) by checking if |
| the data to be written is different from the default or unspecified values. |
| </p></dd> |
| <dt><samp class="option">0</samp></dt> |
| <dt><samp class="option">never</samp></dt> |
| <dd><p>Never write it. |
| </p></dd> |
| <dt><samp class="option">1</samp></dt> |
| <dt><samp class="option">always</samp></dt> |
| <dd><p>Always write it. |
| </p></dd> |
| </dl> |
| </dd> |
| <dt><samp class="option">video_format <var class="var">integer</var></samp></dt> |
| <dd><p>Specifies the video_format written into the sequence display extension |
| indicating the source of the video pictures. The default is ‘<samp class="samp">unspecified</samp>’, |
| can be ‘<samp class="samp">component</samp>’, ‘<samp class="samp">pal</samp>’, ‘<samp class="samp">ntsc</samp>’, ‘<samp class="samp">secam</samp>’ or ‘<samp class="samp">mac</samp>’. |
| For maximum compatibility, use ‘<samp class="samp">component</samp>’. |
| </p></dd> |
| <dt><samp class="option">a53cc <var class="var">boolean</var></samp></dt> |
| <dd><p>Import closed captions (which must be ATSC compatible format) into output. |
| Default is 1 (on). |
| </p></dd> |
| </dl> |
|
|
| <a name="png"></a> |
| <h3 class="section">9.28 png<span class="pull-right"><a class="anchor hidden-xs" href="#png" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-png" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>PNG image encoder. |
| </p> |
| <a name="Options-49"></a> |
| <h4 class="subsection">9.28.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-49" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-49" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">compression_level</samp></dt> |
| <dd><p>Sets the compression level, from 0 to 9(default) |
| </p></dd> |
| </dl> |
|
|
| <a name="Private-options-1"></a> |
| <h4 class="subsection">9.28.2 Private options<span class="pull-right"><a class="anchor hidden-xs" href="#Private-options-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Private-options-1" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">dpi <var class="var">integer</var></samp></dt> |
| <dd><p>Set physical density of pixels, in dots per inch, unset by default |
| </p></dd> |
| <dt><samp class="option">dpm <var class="var">integer</var></samp></dt> |
| <dd><p>Set physical density of pixels, in dots per meter, unset by default |
| </p></dd> |
| <dt><samp class="option">pred <var class="var">method</var></samp></dt> |
| <dd><p>Set prediction method (none, sub, up, avg, paeth, mixed), default is paeth |
| </p></dd> |
| </dl> |
|
|
| <a name="ProRes"></a> |
| <h3 class="section">9.29 ProRes<span class="pull-right"><a class="anchor hidden-xs" href="#ProRes" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-ProRes" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Apple ProRes encoder. |
| </p> |
| <p>FFmpeg contains 2 ProRes encoders, the prores-aw and prores-ks encoder. |
| The used encoder can be chosen with the <code class="code">-vcodec</code> option. |
| </p> |
| <a name="Private-Options-for-prores_002dks"></a> |
| <h4 class="subsection">9.29.1 Private Options for prores-ks<span class="pull-right"><a class="anchor hidden-xs" href="#Private-Options-for-prores_002dks" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Private-Options-for-prores_002dks" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">profile <var class="var">integer</var></samp></dt> |
| <dd><p>Select the ProRes profile to encode |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">proxy</samp>’</dt> |
| <dt>‘<samp class="samp">lt</samp>’</dt> |
| <dt>‘<samp class="samp">standard</samp>’</dt> |
| <dt>‘<samp class="samp">hq</samp>’</dt> |
| <dt>‘<samp class="samp">4444</samp>’</dt> |
| <dt>‘<samp class="samp">4444xq</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">quant_mat <var class="var">integer</var></samp></dt> |
| <dd><p>Select quantization matrix. |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">auto</samp>’</dt> |
| <dt>‘<samp class="samp">default</samp>’</dt> |
| <dt>‘<samp class="samp">proxy</samp>’</dt> |
| <dt>‘<samp class="samp">lt</samp>’</dt> |
| <dt>‘<samp class="samp">standard</samp>’</dt> |
| <dt>‘<samp class="samp">hq</samp>’</dt> |
| </dl> |
| <p>If set to <var class="var">auto</var>, the matrix matching the profile will be picked. |
| If not set, the matrix providing the highest quality, <var class="var">default</var>, will be |
| picked. |
| </p> |
| </dd> |
| <dt><samp class="option">bits_per_mb <var class="var">integer</var></samp></dt> |
| <dd><p>How many bits to allot for coding one macroblock. Different profiles use |
| between 200 and 2400 bits per macroblock, the maximum is 8000. |
| </p> |
| </dd> |
| <dt><samp class="option">mbs_per_slice <var class="var">integer</var></samp></dt> |
| <dd><p>Number of macroblocks in each slice (1-8); the default value (8) |
| should be good in almost all situations. |
| </p> |
| </dd> |
| <dt><samp class="option">vendor <var class="var">string</var></samp></dt> |
| <dd><p>Override the 4-byte vendor ID. |
| A custom vendor ID like <var class="var">apl0</var> would claim the stream was produced by |
| the Apple encoder. |
| </p> |
| </dd> |
| <dt><samp class="option">alpha_bits <var class="var">integer</var></samp></dt> |
| <dd><p>Specify number of bits for alpha component. |
| Possible values are <var class="var">0</var>, <var class="var">8</var> and <var class="var">16</var>. |
| Use <var class="var">0</var> to disable alpha plane coding. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="Speed-considerations"></a> |
| <h4 class="subsection">9.29.2 Speed considerations<span class="pull-right"><a class="anchor hidden-xs" href="#Speed-considerations" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Speed-considerations" aria-hidden="true">TOC</a></span></h4> |
|
|
| <p>In the default mode of operation the encoder has to honor frame constraints |
| (i.e. not produce frames with size bigger than requested) while still making |
| output picture as good as possible. |
| A frame containing a lot of small details is harder to compress and the encoder |
| would spend more time searching for appropriate quantizers for each slice. |
| </p> |
| <p>Setting a higher <samp class="option">bits_per_mb</samp> limit will improve the speed. |
| </p> |
| <p>For the fastest encoding speed set the <samp class="option">qscale</samp> parameter (4 is the |
| recommended value) and do not set a size constraint. |
| </p> |
| <a name="QSV-Encoders"></a> |
| <h3 class="section">9.30 QSV Encoders<span class="pull-right"><a class="anchor hidden-xs" href="#QSV-Encoders" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-QSV-Encoders" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>The family of Intel QuickSync Video encoders (MPEG-2, H.264, HEVC, JPEG/MJPEG, |
| VP9, AV1) |
| </p> |
| <a name="Ratecontrol-Method"></a> |
| <h4 class="subsection">9.30.1 Ratecontrol Method<span class="pull-right"><a class="anchor hidden-xs" href="#Ratecontrol-Method" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Ratecontrol-Method" aria-hidden="true">TOC</a></span></h4> |
| <p>The ratecontrol method is selected as follows: |
| </p><ul class="itemize mark-bullet"> |
| <li>When <samp class="option">global_quality</samp> is specified, a quality-based mode is used. |
| Specifically this means either |
| <ul class="itemize mark-minus"> |
| <li><var class="var">CQP</var> - constant quantizer scale, when the <samp class="option">qscale</samp> codec flag is |
| also set (the <samp class="option">-qscale</samp> ffmpeg option). |
|
|
| </li><li><var class="var">LA_ICQ</var> - intelligent constant quality with lookahead, when the |
| <samp class="option">look_ahead</samp> option is also set. |
|
|
| </li><li><var class="var">ICQ</var> – intelligent constant quality otherwise. For the ICQ modes, global |
| quality range is 1 to 51, with 1 being the best quality. |
| </li></ul> |
|
|
| </li><li>Otherwise when the desired average bitrate is specified with the <samp class="option">b</samp> |
| option, a bitrate-based mode is used. |
| <ul class="itemize mark-minus"> |
| <li><var class="var">LA</var> - VBR with lookahead, when the <samp class="option">look_ahead</samp> option is specified. |
|
|
| </li><li><var class="var">VCM</var> - video conferencing mode, when the <samp class="option">vcm</samp> option is set. |
|
|
| </li><li><var class="var">CBR</var> - constant bitrate, when <samp class="option">maxrate</samp> is specified and equal to |
| the average bitrate. |
|
|
| </li><li><var class="var">VBR</var> - variable bitrate, when <samp class="option">maxrate</samp> is specified, but is higher |
| than the average bitrate. |
|
|
| </li><li><var class="var">AVBR</var> - average VBR mode, when <samp class="option">maxrate</samp> is not specified, both |
| <samp class="option">avbr_accuracy</samp> and <samp class="option">avbr_convergence</samp> are set to non-zero. This |
| mode is available for H264 and HEVC on Windows. |
| </li></ul> |
|
|
| </li><li>Otherwise the default ratecontrol method <var class="var">CQP</var> is used. |
| </li></ul> |
|
|
| <p>Note that depending on your system, a different mode than the one you specified |
| may be selected by the encoder. Set the verbosity level to <var class="var">verbose</var> or |
| higher to see the actual settings used by the QSV runtime. |
| </p> |
| <a name="Global-Options-_002d_003e-MSDK-Options"></a> |
| <h4 class="subsection">9.30.2 Global Options -> MSDK Options<span class="pull-right"><a class="anchor hidden-xs" href="#Global-Options-_002d_003e-MSDK-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Global-Options-_002d_003e-MSDK-Options" aria-hidden="true">TOC</a></span></h4> |
| <p>Additional libavcodec global options are mapped to MSDK options as follows: |
| </p> |
| <ul class="itemize mark-bullet"> |
| <li><samp class="option">g/gop_size</samp> -> <samp class="option">GopPicSize</samp> |
|
|
| </li><li><samp class="option">bf/max_b_frames</samp>+1 -> <samp class="option">GopRefDist</samp> |
|
|
| </li><li><samp class="option">rc_init_occupancy/rc_initial_buffer_occupancy</samp> -> |
| <samp class="option">InitialDelayInKB</samp> |
|
|
| </li><li><samp class="option">slices</samp> -> <samp class="option">NumSlice</samp> |
|
|
| </li><li><samp class="option">refs</samp> -> <samp class="option">NumRefFrame</samp> |
|
|
| </li><li><samp class="option">b_strategy/b_frame_strategy</samp> -> <samp class="option">BRefType</samp> |
|
|
| </li><li><samp class="option">cgop/CLOSED_GOP</samp> codec flag -> <samp class="option">GopOptFlag</samp> |
|
|
| </li><li>For the <var class="var">CQP</var> mode, the <samp class="option">i_qfactor/i_qoffset</samp> and |
| <samp class="option">b_qfactor/b_qoffset</samp> set the difference between <var class="var">QPP</var> and <var class="var">QPI</var>, |
| and <var class="var">QPP</var> and <var class="var">QPB</var> respectively. |
|
|
| </li><li>Setting the <samp class="option">coder</samp> option to the value <var class="var">vlc</var> will make the H.264 |
| encoder use CAVLC instead of CABAC. |
|
|
| </li></ul> |
|
|
| <a name="Common-Options-1"></a> |
| <h4 class="subsection">9.30.3 Common Options<span class="pull-right"><a class="anchor hidden-xs" href="#Common-Options-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Common-Options-1" aria-hidden="true">TOC</a></span></h4> |
| <p>Following options are used by all qsv encoders. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option"><var class="var">async_depth</var></samp></dt> |
| <dd><p>Specifies how many asynchronous operations an application performs |
| before the application explicitly synchronizes the result. If zero, |
| the value is not specified. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">preset</var></samp></dt> |
| <dd><p>This option itemizes a range of choices from veryfast (best speed) to veryslow |
| (best quality). |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">veryfast</samp>’</dt> |
| <dt>‘<samp class="samp">faster</samp>’</dt> |
| <dt>‘<samp class="samp">fast</samp>’</dt> |
| <dt>‘<samp class="samp">medium</samp>’</dt> |
| <dt>‘<samp class="samp">slow</samp>’</dt> |
| <dt>‘<samp class="samp">slower</samp>’</dt> |
| <dt>‘<samp class="samp">veryslow</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option"><var class="var">forced_idr</var></samp></dt> |
| <dd><p>Forcing I frames as IDR frames. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">low_power</var></samp></dt> |
| <dd><p>For encoders set this flag to ON to reduce power consumption and GPU usage. |
| </p></dd> |
| </dl> |
|
|
| <a name="Runtime-Options"></a> |
| <h4 class="subsection">9.30.4 Runtime Options<span class="pull-right"><a class="anchor hidden-xs" href="#Runtime-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Runtime-Options" aria-hidden="true">TOC</a></span></h4> |
| <p>Following options can be used during qsv encoding. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option"><var class="var">global_quality</var></samp></dt> |
| <dt><samp class="option"><var class="var">i_quant_factor</var></samp></dt> |
| <dt><samp class="option"><var class="var">i_quant_offset</var></samp></dt> |
| <dt><samp class="option"><var class="var">b_quant_factor</var></samp></dt> |
| <dt><samp class="option"><var class="var">b_quant_offset</var></samp></dt> |
| <dd><p>Supported in h264_qsv and hevc_qsv. |
| Change these value to reset qsv codec’s qp configuration. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_frame_size</var></samp></dt> |
| <dd><p>Supported in h264_qsv and hevc_qsv. |
| Change this value to reset qsv codec’s MaxFrameSize configuration. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">gop_size</var></samp></dt> |
| <dd><p>Change this value to reset qsv codec’s gop configuration. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">int_ref_type</var></samp></dt> |
| <dt><samp class="option"><var class="var">int_ref_cycle_size</var></samp></dt> |
| <dt><samp class="option"><var class="var">int_ref_qp_delta</var></samp></dt> |
| <dt><samp class="option"><var class="var">int_ref_cycle_dist</var></samp></dt> |
| <dd><p>Supported in h264_qsv and hevc_qsv. |
| Change these value to reset qsv codec’s Intra Refresh configuration. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">qmax</var></samp></dt> |
| <dt><samp class="option"><var class="var">qmin</var></samp></dt> |
| <dt><samp class="option"><var class="var">max_qp_i</var></samp></dt> |
| <dt><samp class="option"><var class="var">min_qp_i</var></samp></dt> |
| <dt><samp class="option"><var class="var">max_qp_p</var></samp></dt> |
| <dt><samp class="option"><var class="var">min_qp_p</var></samp></dt> |
| <dt><samp class="option"><var class="var">max_qp_b</var></samp></dt> |
| <dt><samp class="option"><var class="var">min_qp_b</var></samp></dt> |
| <dd><p>Supported in h264_qsv. |
| Change these value to reset qsv codec’s max/min qp configuration. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">low_delay_brc</var></samp></dt> |
| <dd><p>Supported in h264_qsv, hevc_qsv and av1_qsv. |
| Change this value to reset qsv codec’s low_delay_brc configuration. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">framerate</var></samp></dt> |
| <dd><p>Change this value to reset qsv codec’s framerate configuration. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">bit_rate</var></samp></dt> |
| <dt><samp class="option"><var class="var">rc_buffer_size</var></samp></dt> |
| <dt><samp class="option"><var class="var">rc_initial_buffer_occupancy</var></samp></dt> |
| <dt><samp class="option"><var class="var">rc_max_rate</var></samp></dt> |
| <dd><p>Change these value to reset qsv codec’s bitrate control configuration. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">pic_timing_sei</var></samp></dt> |
| <dd><p>Supported in h264_qsv and hevc_qsv. |
| Change this value to reset qsv codec’s pic_timing_sei configuration. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">qsv_params</var></samp></dt> |
| <dd><p>Set QSV encoder parameters as a colon-separated list of key-value pairs. |
| </p> |
| <p>The <samp class="option">qsv_params</samp> should be formatted as <code class="code">key1=value1:key2=value2:...</code>. |
| </p> |
| <p>These parameters are passed directly to the underlying Intel Quick Sync Video (QSV) encoder using the MFXSetParameter function. |
| </p> |
| <p>Example: |
| </p><div class="example"> |
| <pre class="example-preformatted">ffmpeg -i input.mp4 -c:v h264_qsv -qsv_params "CodingOption1=1:CodingOption2=2" output.mp4 |
| </pre></div> |
|
|
| <p>This option allows fine-grained control over various encoder-specific settings provided by the QSV encoder. |
| </p></dd> |
| </dl> |
|
|
| <a name="H264-options"></a> |
| <h4 class="subsection">9.30.5 H264 options<span class="pull-right"><a class="anchor hidden-xs" href="#H264-options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-H264-options" aria-hidden="true">TOC</a></span></h4> |
| <p>These options are used by h264_qsv |
| </p> |
| <dl class="table"> |
| <dt><samp class="option"><var class="var">extbrc</var></samp></dt> |
| <dd><p>Extended bitrate control. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">recovery_point_sei</var></samp></dt> |
| <dd><p>Set this flag to insert the recovery point SEI message at the beginning of every |
| intra refresh cycle. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">rdo</var></samp></dt> |
| <dd><p>Enable rate distortion optimization. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_frame_size</var></samp></dt> |
| <dd><p>Maximum encoded frame size in bytes. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_frame_size_i</var></samp></dt> |
| <dd><p>Maximum encoded frame size for I frames in bytes. If this value is set as larger |
| than zero, then for I frames the value set by max_frame_size is ignored. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_frame_size_p</var></samp></dt> |
| <dd><p>Maximum encoded frame size for P frames in bytes. If this value is set as larger |
| than zero, then for P frames the value set by max_frame_size is ignored. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_slice_size</var></samp></dt> |
| <dd><p>Maximum encoded slice size in bytes. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">bitrate_limit</var></samp></dt> |
| <dd><p>Toggle bitrate limitations. |
| Modifies bitrate to be in the range imposed by the QSV encoder. Setting this |
| flag off may lead to violation of HRD conformance. Mind that specifying bitrate |
| below the QSV encoder range might significantly affect quality. If on this |
| option takes effect in non CQP modes: if bitrate is not in the range imposed |
| by the QSV encoder, it will be changed to be in the range. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">mbbrc</var></samp></dt> |
| <dd><p>Setting this flag enables macroblock level bitrate control that generally |
| improves subjective visual quality. Enabling this flag may have negative impact |
| on performance and objective visual quality metric. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">low_delay_brc</var></samp></dt> |
| <dd><p>Setting this flag turns on or off LowDelayBRC feature in qsv plugin, which provides |
| more accurate bitrate control to minimize the variance of bitstream size frame |
| by frame. Value: -1-default 0-off 1-on |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">adaptive_i</var></samp></dt> |
| <dd><p>This flag controls insertion of I frames by the QSV encoder. Turn ON this flag |
| to allow changing of frame type from P and B to I. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">adaptive_b</var></samp></dt> |
| <dd><p>This flag controls changing of frame type from B to P. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">p_strategy</var></samp></dt> |
| <dd><p>Enable P-pyramid: 0-default 1-simple 2-pyramid(bf need to be set to 0). |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">b_strategy</var></samp></dt> |
| <dd><p>This option controls usage of B frames as reference. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">dblk_idc</var></samp></dt> |
| <dd><p>This option disable deblocking. It has value in range 0~2. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">cavlc</var></samp></dt> |
| <dd><p>If set, CAVLC is used; if unset, CABAC is used for encoding. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">vcm</var></samp></dt> |
| <dd><p>Video conferencing mode, please see ratecontrol method. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">idr_interval</var></samp></dt> |
| <dd><p>Distance (in I-frames) between IDR frames. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">pic_timing_sei</var></samp></dt> |
| <dd><p>Insert picture timing SEI with pic_struct_syntax element. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">single_sei_nal_unit</var></samp></dt> |
| <dd><p>Put all the SEI messages into one NALU. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_dec_frame_buffering</var></samp></dt> |
| <dd><p>Maximum number of frames buffered in the DPB. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">look_ahead</var></samp></dt> |
| <dd><p>Use VBR algorithm with look ahead. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">look_ahead_depth</var></samp></dt> |
| <dd><p>Depth of look ahead in number frames. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">look_ahead_downsampling</var></samp></dt> |
| <dd><p>Downscaling factor for the frames saved for the lookahead analysis. |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">unknown</samp>’</dt> |
| <dt>‘<samp class="samp">auto</samp>’</dt> |
| <dt>‘<samp class="samp">off</samp>’</dt> |
| <dt>‘<samp class="samp">2x</samp>’</dt> |
| <dt>‘<samp class="samp">4x</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option"><var class="var">int_ref_type</var></samp></dt> |
| <dd><p>Specifies intra refresh type. The major goal of intra refresh is improvement of |
| error resilience without significant impact on encoded bitstream size caused by |
| I frames. The SDK encoder achieves this by encoding part of each frame in |
| refresh cycle using intra MBs. <var class="var">none</var> means no refresh. <var class="var">vertical</var> means |
| vertical refresh, by column of MBs. <var class="var">horizontal</var> means horizontal refresh, |
| by rows of MBs. <var class="var">slice</var> means horizontal refresh by slices without |
| overlapping. In case of <var class="var">slice</var>, in_ref_cycle_size is ignored. To enable |
| intra refresh, B frame should be set to 0. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">int_ref_cycle_size</var></samp></dt> |
| <dd><p>Specifies number of pictures within refresh cycle starting from 2. 0 and 1 are |
| invalid values. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">int_ref_qp_delta</var></samp></dt> |
| <dd><p>Specifies QP difference for inserted intra MBs. This is signed value in |
| [-51, 51] range if target encoding bit-depth for luma samples is 8 and this |
| range is [-63, 63] for 10 bit-depth or [-75, 75] for 12 bit-depth respectively. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">int_ref_cycle_dist</var></samp></dt> |
| <dd><p>Distance between the beginnings of the intra-refresh cycles in frames. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">profile</var></samp></dt> |
| <dd><dl class="table"> |
| <dt>‘<samp class="samp">unknown</samp>’</dt> |
| <dt>‘<samp class="samp">baseline</samp>’</dt> |
| <dt>‘<samp class="samp">main</samp>’</dt> |
| <dt>‘<samp class="samp">high</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option"><var class="var">a53cc</var></samp></dt> |
| <dd><p>Use A53 Closed Captions (if available). |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">aud</var></samp></dt> |
| <dd><p>Insert the Access Unit Delimiter NAL. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">mfmode</var></samp></dt> |
| <dd><p>Multi-Frame Mode. |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">off</samp>’</dt> |
| <dt>‘<samp class="samp">auto</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option"><var class="var">repeat_pps</var></samp></dt> |
| <dd><p>Repeat pps for every frame. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_qp_i</var></samp></dt> |
| <dd><p>Maximum video quantizer scale for I frame. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">min_qp_i</var></samp></dt> |
| <dd><p>Minimum video quantizer scale for I frame. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_qp_p</var></samp></dt> |
| <dd><p>Maximum video quantizer scale for P frame. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">min_qp_p</var></samp></dt> |
| <dd><p>Minimum video quantizer scale for P frame. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_qp_b</var></samp></dt> |
| <dd><p>Maximum video quantizer scale for B frame. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">min_qp_b</var></samp></dt> |
| <dd><p>Minimum video quantizer scale for B frame. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">scenario</var></samp></dt> |
| <dd><p>Provides a hint to encoder about the scenario for the encoding session. |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">unknown</samp>’</dt> |
| <dt>‘<samp class="samp">displayremoting</samp>’</dt> |
| <dt>‘<samp class="samp">videoconference</samp>’</dt> |
| <dt>‘<samp class="samp">archive</samp>’</dt> |
| <dt>‘<samp class="samp">livestreaming</samp>’</dt> |
| <dt>‘<samp class="samp">cameracapture</samp>’</dt> |
| <dt>‘<samp class="samp">videosurveillance</samp>’</dt> |
| <dt>‘<samp class="samp">gamestreaming</samp>’</dt> |
| <dt>‘<samp class="samp">remotegaming</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option"><var class="var">avbr_accuracy</var></samp></dt> |
| <dd><p>Accuracy of the AVBR ratecontrol (unit of tenth of percent). |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">avbr_convergence</var></samp></dt> |
| <dd><p>Convergence of the AVBR ratecontrol (unit of 100 frames) |
| </p> |
| <p>The parameters <var class="var">avbr_accuracy</var> and <var class="var">avbr_convergence</var> are for the |
| average variable bitrate control (AVBR) algorithm. |
| The algorithm focuses on overall encoding quality while meeting the specified |
| bitrate, <var class="var">target_bitrate</var>, within the accuracy range <var class="var">avbr_accuracy</var>, |
| after a <var class="var">avbr_Convergence</var> period. This method does not follow HRD and the |
| instant bitrate is not capped or padded. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">skip_frame</var></samp></dt> |
| <dd><p>Use per-frame metadata "qsv_skip_frame" to skip frame when encoding. This option |
| defines the usage of this metadata. |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">no_skip</samp>’</dt> |
| <dd><p>Frame skipping is disabled. |
| </p></dd> |
| <dt>‘<samp class="samp">insert_dummy</samp>’</dt> |
| <dd><p>Encoder inserts into bitstream frame where all macroblocks are encoded as |
| skipped. |
| </p></dd> |
| <dt>‘<samp class="samp">insert_nothing</samp>’</dt> |
| <dd><p>Similar to insert_dummy, but encoder inserts nothing into bitstream. The skipped |
| frames are still used in brc. For example, gop still include skipped frames, and |
| the frames after skipped frames will be larger in size. |
| </p></dd> |
| <dt>‘<samp class="samp">brc_only</samp>’</dt> |
| <dd><p>skip_frame metadata indicates the number of missed frames before the current |
| frame. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
| <a name="HEVC-Options-1"></a> |
| <h4 class="subsection">9.30.6 HEVC Options<span class="pull-right"><a class="anchor hidden-xs" href="#HEVC-Options-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-HEVC-Options-1" aria-hidden="true">TOC</a></span></h4> |
| <p>These options are used by hevc_qsv |
| </p> |
| <dl class="table"> |
| <dt><samp class="option"><var class="var">extbrc</var></samp></dt> |
| <dd><p>Extended bitrate control. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">recovery_point_sei</var></samp></dt> |
| <dd><p>Set this flag to insert the recovery point SEI message at the beginning of every |
| intra refresh cycle. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">rdo</var></samp></dt> |
| <dd><p>Enable rate distortion optimization. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_frame_size</var></samp></dt> |
| <dd><p>Maximum encoded frame size in bytes. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_frame_size_i</var></samp></dt> |
| <dd><p>Maximum encoded frame size for I frames in bytes. If this value is set as larger |
| than zero, then for I frames the value set by max_frame_size is ignored. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_frame_size_p</var></samp></dt> |
| <dd><p>Maximum encoded frame size for P frames in bytes. If this value is set as larger |
| than zero, then for P frames the value set by max_frame_size is ignored. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_slice_size</var></samp></dt> |
| <dd><p>Maximum encoded slice size in bytes. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">mbbrc</var></samp></dt> |
| <dd><p>Setting this flag enables macroblock level bitrate control that generally |
| improves subjective visual quality. Enabling this flag may have negative impact |
| on performance and objective visual quality metric. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">low_delay_brc</var></samp></dt> |
| <dd><p>Setting this flag turns on or off LowDelayBRC feature in qsv plugin, which provides |
| more accurate bitrate control to minimize the variance of bitstream size frame |
| by frame. Value: -1-default 0-off 1-on |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">adaptive_i</var></samp></dt> |
| <dd><p>This flag controls insertion of I frames by the QSV encoder. Turn ON this flag |
| to allow changing of frame type from P and B to I. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">adaptive_b</var></samp></dt> |
| <dd><p>This flag controls changing of frame type from B to P. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">p_strategy</var></samp></dt> |
| <dd><p>Enable P-pyramid: 0-default 1-simple 2-pyramid(bf need to be set to 0). |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">b_strategy</var></samp></dt> |
| <dd><p>This option controls usage of B frames as reference. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">dblk_idc</var></samp></dt> |
| <dd><p>This option disable deblocking. It has value in range 0~2. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">idr_interval</var></samp></dt> |
| <dd><p>Distance (in I-frames) between IDR frames. |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">begin_only</samp>’</dt> |
| <dd><p>Output an IDR-frame only at the beginning of the stream. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option"><var class="var">load_plugin</var></samp></dt> |
| <dd><p>A user plugin to load in an internal session. |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">none</samp>’</dt> |
| <dt>‘<samp class="samp">hevc_sw</samp>’</dt> |
| <dt>‘<samp class="samp">hevc_hw</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option"><var class="var">load_plugins</var></samp></dt> |
| <dd><p>A :-separate list of hexadecimal plugin UIDs to load in |
| an internal session. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">look_ahead_depth</var></samp></dt> |
| <dd><p>Depth of look ahead in number frames, available when extbrc option is enabled. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">profile</var></samp></dt> |
| <dd><p>Set the encoding profile (scc requires libmfx >= 1.32). |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">unknown</samp>’</dt> |
| <dt>‘<samp class="samp">main</samp>’</dt> |
| <dt>‘<samp class="samp">main10</samp>’</dt> |
| <dt>‘<samp class="samp">mainsp</samp>’</dt> |
| <dt>‘<samp class="samp">rext</samp>’</dt> |
| <dt>‘<samp class="samp">scc</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option"><var class="var">tier</var></samp></dt> |
| <dd><p>Set the encoding tier (only level >= 4 can support high tier). |
| This option only takes effect when the level option is specified. |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">main</samp>’</dt> |
| <dt>‘<samp class="samp">high</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option"><var class="var">gpb</var></samp></dt> |
| <dd><p>1: GPB (generalized P/B frame) |
| </p> |
| <p>0: regular P frame. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">tile_cols</var></samp></dt> |
| <dd><p>Number of columns for tiled encoding. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">tile_rows</var></samp></dt> |
| <dd><p>Number of rows for tiled encoding. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">aud</var></samp></dt> |
| <dd><p>Insert the Access Unit Delimiter NAL. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">pic_timing_sei</var></samp></dt> |
| <dd><p>Insert picture timing SEI with pic_struct_syntax element. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">transform_skip</var></samp></dt> |
| <dd><p>Turn this option ON to enable transformskip. It is supported on platform equal |
| or newer than ICL. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">int_ref_type</var></samp></dt> |
| <dd><p>Specifies intra refresh type. The major goal of intra refresh is improvement of |
| error resilience without significant impact on encoded bitstream size caused by |
| I frames. The SDK encoder achieves this by encoding part of each frame in |
| refresh cycle using intra MBs. <var class="var">none</var> means no refresh. <var class="var">vertical</var> means |
| vertical refresh, by column of MBs. <var class="var">horizontal</var> means horizontal refresh, |
| by rows of MBs. <var class="var">slice</var> means horizontal refresh by slices without |
| overlapping. In case of <var class="var">slice</var>, in_ref_cycle_size is ignored. To enable |
| intra refresh, B frame should be set to 0. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">int_ref_cycle_size</var></samp></dt> |
| <dd><p>Specifies number of pictures within refresh cycle starting from 2. 0 and 1 are |
| invalid values. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">int_ref_qp_delta</var></samp></dt> |
| <dd><p>Specifies QP difference for inserted intra MBs. This is signed value in |
| [-51, 51] range if target encoding bit-depth for luma samples is 8 and this |
| range is [-63, 63] for 10 bit-depth or [-75, 75] for 12 bit-depth respectively. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">int_ref_cycle_dist</var></samp></dt> |
| <dd><p>Distance between the beginnings of the intra-refresh cycles in frames. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_qp_i</var></samp></dt> |
| <dd><p>Maximum video quantizer scale for I frame. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">min_qp_i</var></samp></dt> |
| <dd><p>Minimum video quantizer scale for I frame. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_qp_p</var></samp></dt> |
| <dd><p>Maximum video quantizer scale for P frame. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">min_qp_p</var></samp></dt> |
| <dd><p>Minimum video quantizer scale for P frame. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_qp_b</var></samp></dt> |
| <dd><p>Maximum video quantizer scale for B frame. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">min_qp_b</var></samp></dt> |
| <dd><p>Minimum video quantizer scale for B frame. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">scenario</var></samp></dt> |
| <dd><p>Provides a hint to encoder about the scenario for the encoding session. |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">unknown</samp>’</dt> |
| <dt>‘<samp class="samp">displayremoting</samp>’</dt> |
| <dt>‘<samp class="samp">videoconference</samp>’</dt> |
| <dt>‘<samp class="samp">archive</samp>’</dt> |
| <dt>‘<samp class="samp">livestreaming</samp>’</dt> |
| <dt>‘<samp class="samp">cameracapture</samp>’</dt> |
| <dt>‘<samp class="samp">videosurveillance</samp>’</dt> |
| <dt>‘<samp class="samp">gamestreaming</samp>’</dt> |
| <dt>‘<samp class="samp">remotegaming</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option"><var class="var">avbr_accuracy</var></samp></dt> |
| <dd><p>Accuracy of the AVBR ratecontrol (unit of tenth of percent). |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">avbr_convergence</var></samp></dt> |
| <dd><p>Convergence of the AVBR ratecontrol (unit of 100 frames) |
| </p> |
| <p>The parameters <var class="var">avbr_accuracy</var> and <var class="var">avbr_convergence</var> are for the |
| average variable bitrate control (AVBR) algorithm. |
| The algorithm focuses on overall encoding quality while meeting the specified |
| bitrate, <var class="var">target_bitrate</var>, within the accuracy range <var class="var">avbr_accuracy</var>, |
| after a <var class="var">avbr_Convergence</var> period. This method does not follow HRD and the |
| instant bitrate is not capped or padded. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">skip_frame</var></samp></dt> |
| <dd><p>Use per-frame metadata "qsv_skip_frame" to skip frame when encoding. This option |
| defines the usage of this metadata. |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">no_skip</samp>’</dt> |
| <dd><p>Frame skipping is disabled. |
| </p></dd> |
| <dt>‘<samp class="samp">insert_dummy</samp>’</dt> |
| <dd><p>Encoder inserts into bitstream frame where all macroblocks are encoded as |
| skipped. |
| </p></dd> |
| <dt>‘<samp class="samp">insert_nothing</samp>’</dt> |
| <dd><p>Similar to insert_dummy, but encoder inserts nothing into bitstream. The skipped |
| frames are still used in brc. For example, gop still include skipped frames, and |
| the frames after skipped frames will be larger in size. |
| </p></dd> |
| <dt>‘<samp class="samp">brc_only</samp>’</dt> |
| <dd><p>skip_frame metadata indicates the number of missed frames before the current |
| frame. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
| <a name="MPEG2-Options"></a> |
| <h4 class="subsection">9.30.7 MPEG2 Options<span class="pull-right"><a class="anchor hidden-xs" href="#MPEG2-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-MPEG2-Options" aria-hidden="true">TOC</a></span></h4> |
| <p>These options are used by mpeg2_qsv |
| </p><dl class="table"> |
| <dt><samp class="option"><var class="var">profile</var></samp></dt> |
| <dd><dl class="table"> |
| <dt>‘<samp class="samp">unknown</samp>’</dt> |
| <dt>‘<samp class="samp">simple</samp>’</dt> |
| <dt>‘<samp class="samp">main</samp>’</dt> |
| <dt>‘<samp class="samp">high</samp>’</dt> |
| </dl> |
| </dd> |
| </dl> |
|
|
| <a name="VP9-Options"></a> |
| <h4 class="subsection">9.30.8 VP9 Options<span class="pull-right"><a class="anchor hidden-xs" href="#VP9-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-VP9-Options" aria-hidden="true">TOC</a></span></h4> |
| <p>These options are used by vp9_qsv |
| </p><dl class="table"> |
| <dt><samp class="option"><var class="var">profile</var></samp></dt> |
| <dd><dl class="table"> |
| <dt>‘<samp class="samp">unknown</samp>’</dt> |
| <dt>‘<samp class="samp">profile0</samp>’</dt> |
| <dt>‘<samp class="samp">profile1</samp>’</dt> |
| <dt>‘<samp class="samp">profile2</samp>’</dt> |
| <dt>‘<samp class="samp">profile3</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option"><var class="var">tile_cols</var></samp></dt> |
| <dd><p>Number of columns for tiled encoding (requires libmfx >= 1.29). |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">tile_rows</var></samp></dt> |
| <dd><p>Number of rows for tiled encoding (requires libmfx >= 1.29). |
| </p></dd> |
| </dl> |
|
|
| <a name="AV1-Options"></a> |
| <h4 class="subsection">9.30.9 AV1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#AV1-Options" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-AV1-Options" aria-hidden="true">TOC</a></span></h4> |
| <p>These options are used by av1_qsv (requires libvpl). |
| </p><dl class="table"> |
| <dt><samp class="option"><var class="var">profile</var></samp></dt> |
| <dd><dl class="table"> |
| <dt>‘<samp class="samp">unknown</samp>’</dt> |
| <dt>‘<samp class="samp">main</samp>’</dt> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option"><var class="var">tile_cols</var></samp></dt> |
| <dd><p>Number of columns for tiled encoding. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">tile_rows</var></samp></dt> |
| <dd><p>Number of rows for tiled encoding. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">adaptive_i</var></samp></dt> |
| <dd><p>This flag controls insertion of I frames by the QSV encoder. Turn ON this flag |
| to allow changing of frame type from P and B to I. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">adaptive_b</var></samp></dt> |
| <dd><p>This flag controls changing of frame type from B to P. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">b_strategy</var></samp></dt> |
| <dd><p>This option controls usage of B frames as reference. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">extbrc</var></samp></dt> |
| <dd><p>Extended bitrate control. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">look_ahead_depth</var></samp></dt> |
| <dd><p>Depth of look ahead in number frames, available when extbrc option is enabled. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">low_delay_brc</var></samp></dt> |
| <dd><p>Setting this flag turns on or off LowDelayBRC feature in qsv plugin, which provides |
| more accurate bitrate control to minimize the variance of bitstream size frame |
| by frame. Value: -1-default 0-off 1-on |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_frame_size</var></samp></dt> |
| <dd><p>Set the allowed max size in bytes for each frame. If the frame size exceeds |
| the limitation, encoder will adjust the QP value to control the frame size. |
| Invalid in CQP rate control mode. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_frame_size_i</var></samp></dt> |
| <dd><p>Maximum encoded frame size for I frames in bytes. If this value is set as larger |
| than zero, then for I frames the value set by max_frame_size is ignored. |
| </p> |
| </dd> |
| <dt><samp class="option"><var class="var">max_frame_size_p</var></samp></dt> |
| <dd><p>Maximum encoded frame size for P frames in bytes. If this value is set as larger |
| than zero, then for P frames the value set by max_frame_size is ignored. |
| </p></dd> |
| </dl> |
|
|
| <a name="snow"></a> |
| <h3 class="section">9.31 snow<span class="pull-right"><a class="anchor hidden-xs" href="#snow" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-snow" aria-hidden="true">TOC</a></span></h3> |
|
|
| <a name="Options-50"></a> |
| <h4 class="subsection">9.31.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-50" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-50" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">iterative_dia_size</samp></dt> |
| <dd><p>dia size for the iterative motion estimation |
| </p></dd> |
| </dl> |
|
|
| <a name="VAAPI-encoders"></a> |
| <h3 class="section">9.32 VAAPI encoders<span class="pull-right"><a class="anchor hidden-xs" href="#VAAPI-encoders" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-VAAPI-encoders" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Wrappers for hardware encoders accessible via VAAPI. |
| </p> |
| <p>These encoders only accept input in VAAPI hardware surfaces. If you have input |
| in software frames, use the <samp class="option">hwupload</samp> filter to upload them to the GPU. |
| </p> |
| <p>The following standard libavcodec options are used: |
| </p><ul class="itemize mark-bullet"> |
| <li><samp class="option">g</samp> / <samp class="option">gop_size</samp> |
| </li><li><samp class="option">bf</samp> / <samp class="option">max_b_frames</samp> |
| </li><li><samp class="option">profile</samp> |
|
|
| <p>If not set, this will be determined automatically from the format of the input |
| frames and the profiles supported by the driver. |
| </p></li><li><samp class="option">level</samp> |
| </li><li><samp class="option">b</samp> / <samp class="option">bit_rate</samp> |
| </li><li><samp class="option">maxrate</samp> / <samp class="option">rc_max_rate</samp> |
| </li><li><samp class="option">bufsize</samp> / <samp class="option">rc_buffer_size</samp> |
| </li><li><samp class="option">rc_init_occupancy</samp> / <samp class="option">rc_initial_buffer_occupancy</samp> |
| </li><li><samp class="option">compression_level</samp> |
|
|
| <p>Speed / quality tradeoff: higher values are faster / worse quality. |
| </p></li><li><samp class="option">q</samp> / <samp class="option">global_quality</samp> |
|
|
| <p>Size / quality tradeoff: higher values are smaller / worse quality. |
| </p></li><li><samp class="option">qmin</samp> |
| </li><li><samp class="option">qmax</samp> |
| </li><li><samp class="option">i_qfactor</samp> / <samp class="option">i_quant_factor</samp> |
| </li><li><samp class="option">i_qoffset</samp> / <samp class="option">i_quant_offset</samp> |
| </li><li><samp class="option">b_qfactor</samp> / <samp class="option">b_quant_factor</samp> |
| </li><li><samp class="option">b_qoffset</samp> / <samp class="option">b_quant_offset</samp> |
| </li><li><samp class="option">slices</samp> |
| </li></ul> |
|
|
| <p>All encoders support the following options: |
| </p><dl class="table"> |
| <dt><samp class="option">low_power</samp></dt> |
| <dd><p>Some drivers/platforms offer a second encoder for some codecs intended to use |
| less power than the default encoder; setting this option will attempt to use |
| that encoder. Note that it may support a reduced feature set, so some other |
| options may not be available in this mode. |
| </p> |
| </dd> |
| <dt><samp class="option">idr_interval</samp></dt> |
| <dd><p>Set the number of normal intra frames between full-refresh (IDR) frames in |
| open-GOP mode. The intra frames are still IRAPs, but will not include global |
| headers and may have non-decodable leading pictures. |
| </p> |
| </dd> |
| <dt><samp class="option">b_depth</samp></dt> |
| <dd><p>Set the B-frame reference depth. When set to one (the default), all B-frames |
| will refer only to P- or I-frames. When set to greater values multiple layers |
| of B-frames will be present, frames in each layer only referring to frames in |
| higher layers. |
| </p> |
| </dd> |
| <dt><samp class="option">async_depth</samp></dt> |
| <dd><p>Maximum processing parallelism. Increase this to improve single channel |
| performance. This option doesn’t work if driver doesn’t implement vaSyncBuffer |
| function. Please make sure there are enough hw_frames allocated if a large |
| number of async_depth is used. |
| </p> |
| </dd> |
| <dt><samp class="option">max_frame_size</samp></dt> |
| <dd><p>Set the allowed max size in bytes for each frame. If the frame size exceeds |
| the limitation, encoder will adjust the QP value to control the frame size. |
| Invalid in CQP rate control mode. |
| </p> |
| </dd> |
| <dt><samp class="option">rc_mode</samp></dt> |
| <dd><p>Set the rate control mode to use. A given driver may only support a subset of |
| modes. |
| </p> |
| <p>Possible modes: |
| </p><dl class="table"> |
| <dt><samp class="option">auto</samp></dt> |
| <dd><p>Choose the mode automatically based on driver support and the other options. |
| This is the default. |
| </p></dd> |
| <dt><samp class="option">CQP</samp></dt> |
| <dd><p>Constant-quality. |
| </p></dd> |
| <dt><samp class="option">CBR</samp></dt> |
| <dd><p>Constant-bitrate. |
| </p></dd> |
| <dt><samp class="option">VBR</samp></dt> |
| <dd><p>Variable-bitrate. |
| </p></dd> |
| <dt><samp class="option">ICQ</samp></dt> |
| <dd><p>Intelligent constant-quality. |
| </p></dd> |
| <dt><samp class="option">QVBR</samp></dt> |
| <dd><p>Quality-defined variable-bitrate. |
| </p></dd> |
| <dt><samp class="option">AVBR</samp></dt> |
| <dd><p>Average variable bitrate. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">blbrc</samp></dt> |
| <dd><p>Enable block level rate control, which assigns different bitrate block by block. |
| Invalid for CQP mode. |
| </p> |
| </dd> |
| </dl> |
|
|
| <p>Each encoder also has its own specific options: |
| </p><dl class="table"> |
| <dt><samp class="option">av1_vaapi</samp></dt> |
| <dd><p><samp class="option">profile</samp> sets the value of <em class="emph">seq_profile</em>. |
| <samp class="option">tier</samp> sets the value of <em class="emph">seq_tier</em>. |
| <samp class="option">level</samp> sets the value of <em class="emph">seq_level_idx</em>. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">tiles</samp></dt> |
| <dd><p>Set the number of tiles to encode the input video with, as columns x rows. |
| (default is auto, which means use minimal tile column/row number). |
| </p></dd> |
| <dt><samp class="option">tile_groups</samp></dt> |
| <dd><p>Set tile groups number. All the tiles will be distributed as evenly as possible to |
| each tile group. (default is 1). |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">h264_vaapi</samp></dt> |
| <dd><p><samp class="option">profile</samp> sets the value of <em class="emph">profile_idc</em> and the <em class="emph">constraint_set*_flag</em>s. |
| <samp class="option">level</samp> sets the value of <em class="emph">level_idc</em>. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">coder</samp></dt> |
| <dd><p>Set entropy encoder (default is <em class="emph">cabac</em>). Possible values: |
| </p> |
| <dl class="table"> |
| <dt>‘<samp class="samp">ac</samp>’</dt> |
| <dt>‘<samp class="samp">cabac</samp>’</dt> |
| <dd><p>Use CABAC. |
| </p> |
| </dd> |
| <dt>‘<samp class="samp">vlc</samp>’</dt> |
| <dt>‘<samp class="samp">cavlc</samp>’</dt> |
| <dd><p>Use CAVLC. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">aud</samp></dt> |
| <dd><p>Include access unit delimiters in the stream (not included by default). |
| </p> |
| </dd> |
| <dt><samp class="option">sei</samp></dt> |
| <dd><p>Set SEI message types to include. |
| Some combination of the following values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">identifier</samp>’</dt> |
| <dd><p>Include a <em class="emph">user_data_unregistered</em> message containing information about |
| the encoder. |
| </p></dd> |
| <dt>‘<samp class="samp">timing</samp>’</dt> |
| <dd><p>Include picture timing parameters (<em class="emph">buffering_period</em> and |
| <em class="emph">pic_timing</em> messages). |
| </p></dd> |
| <dt>‘<samp class="samp">recovery_point</samp>’</dt> |
| <dd><p>Include recovery points where appropriate (<em class="emph">recovery_point</em> messages). |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">hevc_vaapi</samp></dt> |
| <dd><p><samp class="option">profile</samp> and <samp class="option">level</samp> set the values of |
| <em class="emph">general_profile_idc</em> and <em class="emph">general_level_idc</em> respectively. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">aud</samp></dt> |
| <dd><p>Include access unit delimiters in the stream (not included by default). |
| </p> |
| </dd> |
| <dt><samp class="option">tier</samp></dt> |
| <dd><p>Set <em class="emph">general_tier_flag</em>. This may affect the level chosen for the stream |
| if it is not explicitly specified. |
| </p> |
| </dd> |
| <dt><samp class="option">sei</samp></dt> |
| <dd><p>Set SEI message types to include. |
| Some combination of the following values: |
| </p><dl class="table"> |
| <dt>‘<samp class="samp">hdr</samp>’</dt> |
| <dd><p>Include HDR metadata if the input frames have it |
| (<em class="emph">mastering_display_colour_volume</em> and <em class="emph">content_light_level</em> |
| messages). |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">tiles</samp></dt> |
| <dd><p>Set the number of tiles to encode the input video with, as columns x rows. |
| Larger numbers allow greater parallelism in both encoding and decoding, but |
| may decrease coding efficiency. |
| </p> |
| </dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">mjpeg_vaapi</samp></dt> |
| <dd><p>Only baseline DCT encoding is supported. The encoder always uses the standard |
| quantisation and huffman tables - <samp class="option">global_quality</samp> scales the standard |
| quantisation table (range 1-100). |
| </p> |
| <p>For YUV, 4:2:0, 4:2:2 and 4:4:4 subsampling modes are supported. RGB is also |
| supported, and will create an RGB JPEG. |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">jfif</samp></dt> |
| <dd><p>Include JFIF header in each frame (not included by default). |
| </p></dd> |
| <dt><samp class="option">huffman</samp></dt> |
| <dd><p>Include standard huffman tables (on by default). Turning this off will save |
| a few hundred bytes in each output frame, but may lose compatibility with some |
| JPEG decoders which don’t fully handle MJPEG. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">mpeg2_vaapi</samp></dt> |
| <dd><p><samp class="option">profile</samp> and <samp class="option">level</samp> set the value of <em class="emph">profile_and_level_indication</em>. |
| </p> |
| </dd> |
| <dt><samp class="option">vp8_vaapi</samp></dt> |
| <dd><p>B-frames are not supported. |
| </p> |
| <p><samp class="option">global_quality</samp> sets the <em class="emph">q_idx</em> used for non-key frames (range 0-127). |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">loop_filter_level</samp></dt> |
| <dt><samp class="option">loop_filter_sharpness</samp></dt> |
| <dd><p>Manually set the loop filter parameters. |
| </p></dd> |
| </dl> |
|
|
| </dd> |
| <dt><samp class="option">vp9_vaapi</samp></dt> |
| <dd><p><samp class="option">global_quality</samp> sets the <em class="emph">q_idx</em> used for P-frames (range 0-255). |
| </p> |
| <dl class="table"> |
| <dt><samp class="option">loop_filter_level</samp></dt> |
| <dt><samp class="option">loop_filter_sharpness</samp></dt> |
| <dd><p>Manually set the loop filter parameters. |
| </p></dd> |
| </dl> |
|
|
| <p>B-frames are supported, but the output stream is always in encode order rather than display |
| order. If B-frames are enabled, it may be necessary to use the <samp class="option">vp9_raw_reorder</samp> |
| bitstream filter to modify the output stream to display frames in the correct order. |
| </p> |
| <p>Only normal frames are produced - the <samp class="option">vp9_superframe</samp> bitstream filter may be |
| required to produce a stream usable with all decoders. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="vbn"></a> |
| <h3 class="section">9.33 vbn<span class="pull-right"><a class="anchor hidden-xs" href="#vbn" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-vbn" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>Vizrt Binary Image encoder. |
| </p> |
| <p>This format is used by the broadcast vendor Vizrt for quick texture streaming. |
| Advanced features of the format such as LZW compression of texture data or |
| generation of mipmaps are not supported. |
| </p> |
| <a name="Options-51"></a> |
| <h4 class="subsection">9.33.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-51" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-51" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">format <var class="var">string</var></samp></dt> |
| <dd><p>Sets the texture compression used by the VBN file. Can be <var class="var">dxt1</var>, |
| <var class="var">dxt5</var> or <var class="var">raw</var>. Default is <var class="var">dxt5</var>. |
| </p></dd> |
| </dl> |
|
|
| <a name="vc2"></a> |
| <h3 class="section">9.34 vc2<span class="pull-right"><a class="anchor hidden-xs" href="#vc2" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-vc2" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>SMPTE VC-2 (previously BBC Dirac Pro). This codec was primarily aimed at |
| professional broadcasting but since it supports yuv420, yuv422 and yuv444 at |
| 8 (limited range or full range), 10 or 12 bits, this makes it suitable for |
| other tasks which require low overhead and low compression (like screen |
| recording). |
| </p> |
| <a name="Options-52"></a> |
| <h4 class="subsection">9.34.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-52" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-52" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">b</samp></dt> |
| <dd><p>Sets target video bitrate. Usually that’s around 1:6 of the uncompressed |
| video bitrate (e.g. for 1920x1080 50fps yuv422p10 that’s around 400Mbps). Higher |
| values (close to the uncompressed bitrate) turn on lossless compression mode. |
| </p> |
| </dd> |
| <dt><samp class="option">field_order</samp></dt> |
| <dd><p>Enables field coding when set (e.g. to tt - top field first) for interlaced |
| inputs. Should increase compression with interlaced content as it splits the |
| fields and encodes each separately. |
| </p> |
| </dd> |
| <dt><samp class="option">wavelet_depth</samp></dt> |
| <dd><p>Sets the total amount of wavelet transforms to apply, between 1 and 5 (default). |
| Lower values reduce compression and quality. Less capable decoders may not be |
| able to handle values of <samp class="option">wavelet_depth</samp> over 3. |
| </p> |
| </dd> |
| <dt><samp class="option">wavelet_type</samp></dt> |
| <dd><p>Sets the transform type. Currently only <var class="var">5_3</var> (LeGall) and <var class="var">9_7</var> |
| (Deslauriers-Dubuc) |
| are implemented, with 9_7 being the one with better compression and thus |
| is the default. |
| </p> |
| </dd> |
| <dt><samp class="option">slice_width</samp></dt> |
| <dt><samp class="option">slice_height</samp></dt> |
| <dd><p>Sets the slice size for each slice. Larger values result in better compression. |
| For compatibility with other more limited decoders use <samp class="option">slice_width</samp> of |
| 32 and <samp class="option">slice_height</samp> of 8. |
| </p> |
| </dd> |
| <dt><samp class="option">tolerance</samp></dt> |
| <dd><p>Sets the undershoot tolerance of the rate control system in percent. This is |
| to prevent an expensive search from being run. |
| </p> |
| </dd> |
| <dt><samp class="option">qm</samp></dt> |
| <dd><p>Sets the quantization matrix preset to use by default or when <samp class="option">wavelet_depth</samp> |
| is set to 5 |
| </p><ul class="itemize mark-minus"> |
| <li><var class="var">default</var> |
| Uses the default quantization matrix from the specifications, extended with |
| values for the fifth level. This provides a good balance between keeping detail |
| and omitting artifacts. |
|
|
| </li><li><var class="var">flat</var> |
| Use a completely zeroed out quantization matrix. This increases PSNR but might |
| reduce perception. Use in bogus benchmarks. |
|
|
| </li><li><var class="var">color</var> |
| Reduces detail but attempts to preserve color at extremely low bitrates. |
| </li></ul> |
|
|
| </dd> |
| </dl> |
|
|
|
|
| <a name="Subtitles-Encoders"></a> |
| <h2 class="chapter">10 Subtitles Encoders<span class="pull-right"><a class="anchor hidden-xs" href="#Subtitles-Encoders" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Subtitles-Encoders" aria-hidden="true">TOC</a></span></h2> |
|
|
| <a name="dvbsub-1"></a> |
| <h3 class="section">10.1 dvbsub<span class="pull-right"><a class="anchor hidden-xs" href="#dvbsub-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-dvbsub-1" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>This codec encodes the bitmap subtitle format that is used in DVB |
| broadcasts and recordings. The bitmaps are typically embedded in a |
| container such as MPEG-TS as a separate stream. |
| </p> |
| <a name="Options-53"></a> |
| <h4 class="subsection">10.1.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-53" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-53" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">min_bpp <var class="var">integer (2, 4, or 8)</var></samp></dt> |
| <dd><p>Set a minimum bits-per-pixel value for the subtitle color lookup tables. |
| </p> |
| <p>DVB supports 2, 4, and 8 bits-per-pixel color lookup tables. This |
| option enables forcing a particular bits-per-pixel value regardless of |
| the number of colors. Since not all players support or properly |
| support 2 bits-per-pixel, this value defaults to 4. |
| </p> |
| </dd> |
| </dl> |
|
|
| <a name="dvdsub-1"></a> |
| <h3 class="section">10.2 dvdsub<span class="pull-right"><a class="anchor hidden-xs" href="#dvdsub-1" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-dvdsub-1" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>This codec encodes the bitmap subtitle format that is used in DVDs. |
| Typically they are stored in VOBSUB file pairs (*.idx + *.sub), |
| and they can also be used in Matroska files. |
| </p> |
| <a name="Options-54"></a> |
| <h4 class="subsection">10.2.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-54" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-54" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">palette</samp></dt> |
| <dd><p>Specify the global palette used by the bitmaps. |
| </p> |
| <p>The format for this option is a string containing 16 24-bits hexadecimal |
| numbers (without 0x prefix) separated by commas, for example <code class="code">0d00ee, |
| ee450d, 101010, eaeaea, 0ce60b, ec14ed, ebff0b, 0d617a, 7b7b7b, d1d1d1, |
| 7b2a0e, 0d950c, 0f007b, cf0dec, cfa80c, 7c127b</code>. |
| </p> |
| </dd> |
| <dt><samp class="option">even_rows_fix</samp></dt> |
| <dd><p>When set to 1, enable a work-around that makes the number of pixel rows |
| even in all subtitles. This fixes a problem with some players that |
| cut off the bottom row if the number is odd. The work-around just adds |
| a fully transparent row if needed. The overhead is low, typically |
| one byte per subtitle on average. |
| </p> |
| <p>By default, this work-around is disabled. |
| </p></dd> |
| </dl> |
|
|
| <a name="lrc"></a> |
| <h3 class="section">10.3 lrc<span class="pull-right"><a class="anchor hidden-xs" href="#lrc" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-lrc" aria-hidden="true">TOC</a></span></h3> |
|
|
| <p>This codec encodes the LRC lyrics format. |
| </p> |
| <a name="Options-55"></a> |
| <h4 class="subsection">10.3.1 Options<span class="pull-right"><a class="anchor hidden-xs" href="#Options-55" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Options-55" aria-hidden="true">TOC</a></span></h4> |
|
|
| <dl class="table"> |
| <dt><samp class="option">precision</samp></dt> |
| <dd><p>Specify the precision of the fractional part of the timestamp. Time base is |
| determined based on this value. |
| </p> |
| <p>Defaults to 2 for centiseconds. |
| </p></dd> |
| </dl> |
|
|
|
|
| <a name="See-Also"></a> |
| <h2 class="chapter">11 See Also<span class="pull-right"><a class="anchor hidden-xs" href="#See-Also" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-See-Also" aria-hidden="true">TOC</a></span></h2> |
|
|
| <p><a class="url" href="ffmpeg.html">ffmpeg</a>, <a class="url" href="ffplay.html">ffplay</a>, <a class="url" href="ffprobe.html">ffprobe</a>, |
| <a class="url" href="libavcodec.html">libavcodec</a> |
| </p> |
|
|
| <a name="Authors"></a> |
| <h2 class="chapter">12 Authors<span class="pull-right"><a class="anchor hidden-xs" href="#Authors" aria-hidden="true">#</a> <a class="anchor hidden-xs"href="#toc-Authors" aria-hidden="true">TOC</a></span></h2> |
|
|
| <p>The FFmpeg developers. |
| </p> |
| <p>For details about the authorship, see the Git history of the project |
| (https://git.ffmpeg.org/ffmpeg), e.g. by typing the command |
| <code class="command">git log</code> in the FFmpeg source directory, or browsing the |
| online repository at <a class="url" href="https://git.ffmpeg.org/ffmpeg">https://git.ffmpeg.org/ffmpeg</a>. |
| </p> |
| <p>Maintainers for the specific components are listed in the file |
| <samp class="file">MAINTAINERS</samp> in the source code tree. |
| </p> |
|
|
| <p style="font-size: small;"> |
| This document was generated using <a class="uref" href="https://www.gnu.org/software/texinfo/"><em class="emph">makeinfo</em></a>. |
| </p> |
| </div> |
| </body> |
| </html> |
|
|
