File size: 2,994 Bytes
d604241 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 |
cimport libav as lib
from av.audio.format cimport AudioFormat, get_audio_format
from av.audio.frame cimport AudioFrame, alloc_audio_frame
from av.audio.layout cimport AudioLayout, get_audio_layout
from av.codec.hwaccel cimport HWAccel
from av.frame cimport Frame
from av.packet cimport Packet
cdef class AudioCodecContext(CodecContext):
cdef _init(self, lib.AVCodecContext *ptr, const lib.AVCodec *codec, HWAccel hwaccel):
CodecContext._init(self, ptr, codec, hwaccel)
cdef _prepare_frames_for_encode(self, Frame input_frame):
cdef AudioFrame frame = input_frame
cdef bint allow_var_frame_size = self.ptr.codec.capabilities & lib.AV_CODEC_CAP_VARIABLE_FRAME_SIZE
# Note that the resampler will simply return an input frame if there is
# no resampling to be done. The control flow was just a little easier this way.
if not self.resampler:
self.resampler = AudioResampler(
format=self.format,
layout=self.layout,
rate=self.ptr.sample_rate,
frame_size=None if allow_var_frame_size else self.ptr.frame_size
)
frames = self.resampler.resample(frame)
# flush if input frame is None
if input_frame is None:
frames.append(None)
return frames
cdef Frame _alloc_next_frame(self):
return alloc_audio_frame()
cdef _setup_decoded_frame(self, Frame frame, Packet packet):
CodecContext._setup_decoded_frame(self, frame, packet)
cdef AudioFrame aframe = frame
aframe._init_user_attributes()
@property
def frame_size(self):
"""
Number of samples per channel in an audio frame.
:type: int
"""
return self.ptr.frame_size
@property
def sample_rate(self):
"""
Sample rate of the audio data, in samples per second.
:type: int
"""
return self.ptr.sample_rate
@sample_rate.setter
def sample_rate(self, int value):
self.ptr.sample_rate = value
@property
def rate(self):
"""Another name for :attr:`sample_rate`."""
return self.sample_rate
@rate.setter
def rate(self, value):
self.sample_rate = value
@property
def channels(self):
return self.layout.nb_channels
@property
def layout(self):
"""
The audio channel layout.
:type: AudioLayout
"""
return get_audio_layout(self.ptr.ch_layout)
@layout.setter
def layout(self, value):
cdef AudioLayout layout = AudioLayout(value)
self.ptr.ch_layout = layout.layout
@property
def format(self):
"""
The audio sample format.
:type: AudioFormat
"""
return get_audio_format(self.ptr.sample_fmt)
@format.setter
def format(self, value):
cdef AudioFormat format = AudioFormat(value)
self.ptr.sample_fmt = format.sample_fmt
|