| import cython |
| from cython.cimports import libav as lib |
| from cython.cimports.av.buffer import ByteSource, bytesource |
| from cython.cimports.av.codec.context import CodecContext |
| from cython.cimports.av.error import err_check |
| from cython.cimports.av.packet import Packet |
| from cython.cimports.av.subtitles.subtitle import SubtitleProxy, SubtitleSet |
| from cython.cimports.cpython.bytes import PyBytes_FromStringAndSize |
| from cython.cimports.libc.string import memcpy |
|
|
|
|
| @cython.final |
| @cython.cclass |
| class SubtitleCodecContext(CodecContext): |
| @property |
| def subtitle_header(self) -> bytes | None: |
| """Get the subtitle header data (ASS/SSA format for text subtitles).""" |
| if ( |
| self.ptr.subtitle_header == cython.NULL |
| or self.ptr.subtitle_header_size <= 0 |
| ): |
| return None |
| return PyBytes_FromStringAndSize( |
| cython.cast(cython.p_char, self.ptr.subtitle_header), |
| self.ptr.subtitle_header_size, |
| ) |
|
|
| @subtitle_header.setter |
| def subtitle_header(self, data: bytes | None) -> None: |
| """Set the subtitle header data.""" |
| source: ByteSource |
| if data is None: |
| lib.av_freep(cython.address(self.ptr.subtitle_header)) |
| self.ptr.subtitle_header_size = 0 |
| else: |
| source = bytesource(data) |
| self.ptr.subtitle_header = cython.cast( |
| cython.p_uchar, |
| lib.av_realloc( |
| self.ptr.subtitle_header, |
| source.length + lib.AV_INPUT_BUFFER_PADDING_SIZE, |
| ), |
| ) |
| if not self.ptr.subtitle_header: |
| raise MemoryError("Cannot allocate subtitle_header") |
| memcpy(self.ptr.subtitle_header, source.ptr, source.length) |
| self.ptr.subtitle_header_size = cython.cast(cython.int, source.length) |
| self.subtitle_header_set = True |
|
|
| def __dealloc__(self) -> None: |
| if self.ptr and self.subtitle_header_set: |
| lib.av_freep(cython.address(self.ptr.subtitle_header)) |
|
|
| def encode_subtitle(self, subtitle: SubtitleSet) -> Packet: |
| """ |
| Encode a SubtitleSet into a Packet. |
| |
| Args: |
| subtitle: The SubtitleSet to encode |
| |
| Returns: |
| A Packet containing the encoded subtitle data |
| """ |
| if not self.codec.ptr: |
| raise ValueError("Cannot encode with unknown codec") |
|
|
| self.open(strict=False) |
|
|
| buf: cython.p_uchar = cython.cast(cython.p_uchar, lib.av_malloc(1024 * 1024)) |
| if buf == cython.NULL: |
| raise MemoryError() |
|
|
| ret: cython.int = lib.avcodec_encode_subtitle( |
| self.ptr, |
| buf, |
| 1024 * 1024, |
| cython.address(subtitle.proxy.struct), |
| ) |
| if ret < 0: |
| lib.av_free(buf) |
| err_check(ret, "avcodec_encode_subtitle()") |
|
|
| packet: Packet = Packet(ret) |
| memcpy(packet.ptr.data, buf, ret) |
| lib.av_free(buf) |
| packet.ptr.pts = subtitle.proxy.struct.pts |
| packet.ptr.dts = subtitle.proxy.struct.pts |
| packet.ptr.duration = ( |
| subtitle.proxy.struct.end_display_time |
| - subtitle.proxy.struct.start_display_time |
| ) |
|
|
| return packet |
|
|
| @cython.cfunc |
| def _decode(self, packet: Packet | None): |
| """Decode a subtitle packet, returning a list of :class:`.Subtitle` objects |
| if a subtitle was decoded, or an empty list otherwise.""" |
| if not self.codec.ptr: |
| raise ValueError("cannot decode unknown codec") |
|
|
| if packet is None: |
| raise RuntimeError("packet cannot be None") |
|
|
| self.open(strict=False) |
| proxy: SubtitleProxy = SubtitleProxy() |
| got_frame: cython.int = 0 |
|
|
| err_check( |
| lib.avcodec_decode_subtitle2( |
| self.ptr, |
| cython.address(proxy.struct), |
| cython.address(got_frame), |
| packet.ptr, |
| ) |
| ) |
|
|
| if got_frame: |
| return list(SubtitleSet(proxy)) |
| return [] |
|
|
| @cython.ccall |
| def decode2(self, packet: Packet): |
| """ |
| Returns SubtitleSet if you really need it. |
| """ |
| if not self.codec.ptr: |
| raise ValueError("cannot decode unknown codec") |
|
|
| self.open(strict=False) |
|
|
| proxy: SubtitleProxy = SubtitleProxy() |
| got_frame: cython.int = 0 |
|
|
| err_check( |
| lib.avcodec_decode_subtitle2( |
| self.ptr, |
| cython.address(proxy.struct), |
| cython.address(got_frame), |
| packet.ptr, |
| ) |
| ) |
|
|
| if got_frame: |
| return SubtitleSet(proxy) |
| return None |
|
|
