bool TheoraDecoder::TheoraVideoTrack::decodePacket(ogg_packet &oggPacket) {
if (th_decode_packetin(_theoraDecode, &oggPacket, 0) == 0) {
_curFrame++;
// Convert YUV data to RGB data
th_ycbcr_buffer yuv;
th_decode_ycbcr_out(_theoraDecode, yuv);
translateYUVtoRGBA(yuv);
double time = th_granule_time(_theoraDecode, oggPacket.granulepos);
// We need to calculate when the next frame should be shown
// This is all in floating point because that's what the Ogg code gives us
// Ogg is a lossy container format, so it doesn't always list the time to the
// next frame. In such cases, we need to calculate it ourselves.
if (time == -1.0)
_nextFrameStartTime += _frameRate.getInverse().toDouble();
else
_nextFrameStartTime = time;
return true;
}
return false;
}
const Graphics::Surface *TheoraDecoder::decodeNextFrame() {
// First, let's get our frame
while (_theoraPacket) {
// theora is one in, one out...
if (ogg_stream_packetout(&_theoraOut, &_oggPacket) > 0) {
if (_ppInc) {
_ppLevel += _ppInc;
th_decode_ctl(_theoraDecode, TH_DECCTL_SET_PPLEVEL, &_ppLevel, sizeof(_ppLevel));
_ppInc = 0;
}
if (th_decode_packetin(_theoraDecode, &_oggPacket, NULL) == 0) {
_curFrame++;
// Convert YUV data to RGB data
th_ycbcr_buffer yuv;
th_decode_ycbcr_out(_theoraDecode, yuv);
translateYUVtoRGBA(yuv);
if (_curFrame == 0)
_startTime = g_system->getMillis();
double time = th_granule_time(_theoraDecode, _oggPacket.granulepos);
// We need to calculate when the next frame should be shown
// This is all in floating point because that's what the Ogg code gives us
// Ogg is a lossy container format, so it doesn't always list the time to the
// next frame. In such cases, we need to calculate it ourselves.
if (time == -1.0)
_nextFrameStartTime += _frameRate.getInverse().toDouble();
else
_nextFrameStartTime = time;
// break out
break;
}
} else {
// If we can't get any more frames, we're done.
if (_theoraOut.e_o_s || _fileStream->eos()) {
_endOfVideo = true;
break;
}
// Queue more data
bufferData();
while (ogg_sync_pageout(&_oggSync, &_oggPage) > 0)
queuePage(&_oggPage);
}
// Update audio if we can
queueAudio();
}
// Force at least some audio to be buffered
// TODO: 5 is very arbitrary. We probably should do something like QuickTime does.
while (!_endOfAudio && _audStream->numQueuedStreams() < 5) {
bufferData();
while (ogg_sync_pageout(&_oggSync, &_oggPage) > 0)
queuePage(&_oggPage);
bool queuedAudio = queueAudio();
if ((_vorbisOut.e_o_s || _fileStream->eos()) && !queuedAudio) {
_endOfAudio = true;
break;
}
}
return &_displaySurface;
}
