bool AVIDecoder::seekIntern(const Audio::Timestamp &time) {
// Can't seek beyond the end
if (time > getDuration())
return false;
// Track down our video track (optionally audio too).
// We only support seeking with one track right now.
AVIVideoTrack *videoTrack = 0;
AVIAudioTrack *audioTrack = 0;
int videoIndex = -1;
int audioIndex = -1;
uint trackID = 0;
for (TrackListIterator it = getTrackListBegin(); it != getTrackListEnd(); it++, trackID++) {
if ((*it)->getTrackType() == Track::kTrackTypeVideo) {
if (videoTrack) {
// Already have one
// -> Not supported
return false;
}
videoTrack = (AVIVideoTrack *)*it;
videoIndex = trackID;
} else if ((*it)->getTrackType() == Track::kTrackTypeAudio) {
if (audioTrack) {
// Already have one
// -> Not supported
return false;
}
audioTrack = (AVIAudioTrack *)*it;
audioIndex = trackID;
}
}
// Need a video track to go forwards
// If there isn't a video track, why would anyone be using AVI then?
if (!videoTrack)
return false;
// If we seek directly to the end, just mark the tracks as over
if (time == getDuration()) {
videoTrack->setCurFrame(videoTrack->getFrameCount() - 1);
if (audioTrack)
audioTrack->resetStream();
return true;
}
// Get the frame we should be on at this time
uint frame = videoTrack->getFrameAtTime(time);
// Reset any palette, if necessary
videoTrack->useInitialPalette();
int lastKeyFrame = -1;
int frameIndex = -1;
int lastRecord = -1;
uint curFrame = 0;
// Go through and figure out where we should be
// If there's a palette, we need to find the palette too
for (uint32 i = 0; i < _indexEntries.size(); i++) {
const OldIndex &index = _indexEntries[i];
if (index.id == ID_REC) {
// Keep track of any records we find
lastRecord = i;
} else {
if (getStreamIndex(index.id) != videoIndex)
continue;
uint16 streamType = getStreamType(index.id);
if (streamType == kStreamTypePaletteChange) {
// We need to handle any palette change we see since there's no
// flag to tell if this is a "key" palette.
// Decode the palette
_fileStream->seek(_indexEntries[i].offset + 8);
Common::SeekableReadStream *chunk = 0;
if (_indexEntries[i].size != 0)
chunk = _fileStream->readStream(_indexEntries[i].size);
videoTrack->loadPaletteFromChunk(chunk);
} else {
// Check to see if this is a keyframe
// The first frame has to be a keyframe
if ((_indexEntries[i].flags & AVIIF_INDEX) || curFrame == 0)
lastKeyFrame = i;
// Did we find the target frame?
if (frame == curFrame) {
frameIndex = i;
break;
}
curFrame++;
}
}
}
if (frameIndex < 0) // This shouldn't happen.
return false;
if (audioTrack) {
// We need to find where the start of audio should be.
// Which is exactly 'initialFrames' audio chunks back from where
// our found frame is.
// Recreate the audio stream
audioTrack->resetStream();
uint framesNeeded = _header.initialFrames;
uint startAudioChunk = 0;
int startAudioSearch = (lastRecord < 0) ? (frameIndex - 1) : (lastRecord - 1);
for (int i = startAudioSearch; i >= 0; i--) {
if (getStreamIndex(_indexEntries[i].id) != audioIndex)
continue;
assert(getStreamType(_indexEntries[i].id) == kStreamTypeAudio);
framesNeeded--;
if (framesNeeded == 0) {
startAudioChunk = i;
break;
}
}
// Now go forward and queue them all
for (int i = startAudioChunk; i <= startAudioSearch; i++) {
if (_indexEntries[i].id == ID_REC)
continue;
if (getStreamIndex(_indexEntries[i].id) != audioIndex)
continue;
assert(getStreamType(_indexEntries[i].id) == kStreamTypeAudio);
_fileStream->seek(_indexEntries[i].offset + 8);
Common::SeekableReadStream *chunk = _fileStream->readStream(_indexEntries[i].size);
audioTrack->queueSound(chunk);
}
// Skip any audio to bring us to the right time
audioTrack->skipAudio(time, videoTrack->getFrameTime(frame));
}
// Decode from keyFrame to curFrame - 1
for (int i = lastKeyFrame; i < frameIndex; i++) {
if (_indexEntries[i].id == ID_REC)
continue;
if (getStreamIndex(_indexEntries[i].id) != videoIndex)
continue;
uint16 streamType = getStreamType(_indexEntries[i].id);
// Ignore palettes, they were already handled
if (streamType == kStreamTypePaletteChange)
continue;
// Frame, hopefully
_fileStream->seek(_indexEntries[i].offset + 8);
Common::SeekableReadStream *chunk = 0;
if (_indexEntries[i].size != 0)
chunk = _fileStream->readStream(_indexEntries[i].size);
videoTrack->decodeFrame(chunk);
}
// Seek to the right spot
// To the beginning of the last record, or frame if that doesn't exist
if (lastRecord >= 0)
_fileStream->seek(_indexEntries[lastRecord].offset);
else
_fileStream->seek(_indexEntries[frameIndex].offset);
videoTrack->setCurFrame((int)frame - 1);
return true;
}
bool AVIDecoder::seekIntern(const Audio::Timestamp &time) {
// Can't seek beyond the end
if (time > getDuration())
return false;
// Get our video
AVIVideoTrack *videoTrack = (AVIVideoTrack *)_videoTracks[0].track;
uint32 videoIndex = _videoTracks[0].index;
// If we seek directly to the end, just mark the tracks as over
if (time == getDuration()) {
videoTrack->setCurFrame(videoTrack->getFrameCount() - 1);
for (TrackListIterator it = getTrackListBegin(); it != getTrackListEnd(); it++)
if ((*it)->getTrackType() == Track::kTrackTypeAudio)
((AVIAudioTrack *)*it)->resetStream();
return true;
}
// Get the frame we should be on at this time
uint frame = videoTrack->getFrameAtTime(time);
// Reset any palette, if necessary
videoTrack->useInitialPalette();
int lastKeyFrame = -1;
int frameIndex = -1;
uint curFrame = 0;
// Go through and figure out where we should be
// If there's a palette, we need to find the palette too
for (uint32 i = 0; i < _indexEntries.size(); i++) {
const OldIndex &index = _indexEntries[i];
// We don't care about RECs
if (index.id == ID_REC)
continue;
// We're only looking at entries for this track
if (getStreamIndex(index.id) != videoIndex)
continue;
uint16 streamType = getStreamType(index.id);
if (streamType == kStreamTypePaletteChange) {
// We need to handle any palette change we see since there's no
// flag to tell if this is a "key" palette.
// Decode the palette
_fileStream->seek(_indexEntries[i].offset + 8);
Common::SeekableReadStream *chunk = 0;
if (_indexEntries[i].size != 0)
chunk = _fileStream->readStream(_indexEntries[i].size);
videoTrack->loadPaletteFromChunk(chunk);
} else {
// Check to see if this is a keyframe
// The first frame has to be a keyframe
if ((_indexEntries[i].flags & AVIIF_INDEX) || curFrame == 0)
lastKeyFrame = i;
// Did we find the target frame?
if (frame == curFrame) {
frameIndex = i;
break;
}
curFrame++;
}
}
if (frameIndex < 0) // This shouldn't happen.
return false;
// Update all the audio tracks
for (uint32 i = 0; i < _audioTracks.size(); i++) {
AVIAudioTrack *audioTrack = (AVIAudioTrack *)_audioTracks[i].track;
// Recreate the audio stream
audioTrack->resetStream();
// Set the chunk index for the track
audioTrack->setCurChunk(frame);
uint32 chunksFound = 0;
for (uint32 j = 0; j < _indexEntries.size(); j++) {
const OldIndex &index = _indexEntries[j];
// Continue ignoring RECs
if (index.id == ID_REC)
continue;
if (getStreamIndex(index.id) == _audioTracks[i].index) {
if (chunksFound == frame) {
_fileStream->seek(index.offset + 8);
Common::SeekableReadStream *audioChunk = _fileStream->readStream(index.size);
audioTrack->queueSound(audioChunk);
_audioTracks[i].chunkSearchOffset = (j == _indexEntries.size() - 1) ? _movieListEnd : _indexEntries[j + 1].offset;
break;
}
chunksFound++;
}
}
// Skip any audio to bring us to the right time
audioTrack->skipAudio(time, videoTrack->getFrameTime(frame));
}
// Decode from keyFrame to curFrame - 1
for (int i = lastKeyFrame; i < frameIndex; i++) {
if (_indexEntries[i].id == ID_REC)
continue;
if (getStreamIndex(_indexEntries[i].id) != videoIndex)
continue;
uint16 streamType = getStreamType(_indexEntries[i].id);
// Ignore palettes, they were already handled
if (streamType == kStreamTypePaletteChange)
continue;
// Frame, hopefully
_fileStream->seek(_indexEntries[i].offset + 8);
Common::SeekableReadStream *chunk = 0;
if (_indexEntries[i].size != 0)
chunk = _fileStream->readStream(_indexEntries[i].size);
videoTrack->decodeFrame(chunk);
}
// Set the video track's frame
videoTrack->setCurFrame((int)frame - 1);
// Set the video track's search offset to the right spot
_videoTracks[0].chunkSearchOffset = _indexEntries[frameIndex].offset;
return true;
}