thirdparty/scummvm
2
0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

VIDEO: Simplify AVIDecoder reverse playback special handling

Browse source
This commit is contained in:
Paul Gilbert 2017-09-03 19:52:48 -04:00
parent 22e24d7c0b
commit e72a1d7c46
1 changed files with 21 additions and 6 deletions
Download patch file Download diff file Expand all files Collapse all files

27
video/avi_decoder.cpp
View file

@ -130,20 +130,35 @@ bool AVIDecoder::isSeekable() const {
}
const Graphics::Surface *AVIDecoder::decodeNextFrame() {
// When playing in reverse, we need to seek to the correct prior frame
AVIVideoTrack *track = nullptr;
bool isReversed = false;
int frameNum;
// Check whether the video is playing in revese
for (int idx = _videoTracks.size() - 1; idx >= 0; --idx) {
track = static_cast<AVIVideoTrack *>(_videoTracks[idx].track);
isReversed |= track->isReversed();
}
if (isReversed) {
Audio::Timestamp time = track->getFrameTime(getCurFrame());
seekIntern(time);
// For reverse mode we need to keep seeking to just before the
// desired frame prior to actually decoding a frame
frameNum = getCurFrame();
seekIntern(track->getFrameTime(frameNum));
}
return VideoDecoder::decodeNextFrame();
// Decode the next frame
const Graphics::Surface *frame = VideoDecoder::decodeNextFrame();
if (isReversed) {
// In reverse mode, set next frame to be the prior frame number
for (int idx = _videoTracks.size() - 1; idx >= 0; --idx) {
track = static_cast<AVIVideoTrack *>(_videoTracks[idx].track);
track->setCurFrame(frameNum - 1);
}
}
return frame;
}
const Graphics::Surface *AVIDecoder::decodeNextTransparency() {
@ -746,7 +761,7 @@ bool AVIDecoder::seekIntern(const Audio::Timestamp &time) {
seekTransparencyFrame(frame);
// Set the video track's frame
videoTrack->setCurFrame(videoTrack->isReversed() ? frame : frame - 1);
videoTrack->setCurFrame(frame - 1);
// Set the video track's search offset to the right spot
_videoTracks[0].chunkSearchOffset = _indexEntries[frameIndex].offset;
@ -788,7 +803,7 @@ void AVIDecoder::seekTransparencyFrame(int frame) {
}
}
transTrack->setCurFrame((int)frame - 1);
transTrack->setCurFrame(frame - 1);
}
byte AVIDecoder::getStreamIndex(uint32 tag) {