def _createStream(self):
"""Create the AVStream and open the codec.
"""
# Allocate a new stream
stream = avformat.av_new_stream(self._formatCtx, self._formatCtx.nb_streams)
# Initialize it as a video stream
avcodec.avcodec_get_context_defaults2(stream.codec.contents, decls.CODEC_TYPE_VIDEO)
outputFormat = self._formatCtx.oformat.contents
codecCtx = stream.codec.contents
if outputFormat.flags & decls.AVFMT_GLOBALHEADER:
stream.codec.contents.flags |= decls.CODEC_FLAG_GLOBAL_HEADER
# Prepare the codec...
codecId = avformat.av_guess_codec(outputFormat, decls.CODEC_TYPE_VIDEO, fileName=self._formatCtx.filename)
if codecId is None:
raise ValueError("Could not determine video codec to use for encoding the video.")
codec = avcodec.avcodec_find_encoder(codecId)
if codec is None:
raise ValueError("Could not find encoder.")
if codec.supported_framerates:
print "mediafile: supported framerates available"
else:
print "mediafile: supported framerates not available"
codecCtx.codec_id = codecId
num,den = self._frameRate
codecCtx.time_base.den = num
codecCtx.time_base.num = den
width,height = self._size
codecCtx.width = width
codecCtx.height = height
codecCtx.sample_aspect_ratio = avutil.av_d2q(self._pixelAspect, 255)
codecCtx.pix_fmt = decls.PIX_FMT_YUV420P
stream.sample_aspect_ratio = codecCtx.sample_aspect_ratio
# Check if the codec supports the pixel format (if not, switch the format)
if codec.pix_fmts:
i = 0
while codec.pix_fmts[i]!=-1:
if codecCtx.pix_fmt==codec.pix_fmts[i]:
break
i += 1
else:
codecCtx.pix_fmt = codec.pix_fmts[0]
# Open the codec
avcodec.avcodec_open(codecCtx, codec)
return stream
def __init__(self, stream):
"""Constructor.
stream is an AVStream object.
"""
object.__init__(self)
# Data callback
self._dataCallback = None
# AVStream object
self._stream = stream
# Get the codec context of the stream (AVCodecContext)
self._codecCtx = stream.codec.contents
# Obtain an appropriate decoder (AVCodec)...
self._codec = avcodec.avcodec_find_decoder(self._codecCtx.codec_id)
if self._codec is not None:
# Open the codec
avcodec.avcodec_open(self._codecCtx, self._codec)
