Merge "Trust the Cues element" (8d0648ef) · Commits · e / os / android_frameworks_av

media/libstagefright/matroska/MatroskaExtractor.cpp

+22 −44

Original line number	Diff line number	Diff line
		@@ -95,7 +95,7 @@ struct BlockIterator {
		void reset();

		void seek(
		int64_t seekTimeUs, bool seekToKeyFrame,
		int64_t seekTimeUs, bool isAudio,
		int64_t *actualFrameTimeUs);

		const mkvparser::Block *block() const;
		@@ -307,7 +307,7 @@ void BlockIterator::reset() {
		}

		void BlockIterator::seek(
		int64_t seekTimeUs, bool seekToKeyFrame,
		int64_t seekTimeUs, bool isAudio,
		int64_t *actualFrameTimeUs) {
		Mutex::Autolock autoLock(mExtractor->mLock);

		@@ -372,9 +372,7 @@ void BlockIterator::seek(
		}
		}

		// Find the video track for seeking. It doesn't make sense to search the
		// audio track because we'd still want to make sure we're jumping to a
		// keyframe in the video track.
		// The Cue index is built around video keyframes
		mkvparser::Tracks const *pTracks = pSegment->GetTracks();
		const mkvparser::Track *pTrack = NULL;
		for (size_t index = 0; index < pTracks->GetTracksCount(); ++index) {
		@@ -385,57 +383,37 @@ void BlockIterator::seek(
		}
		}

		// Always search based on the video track, but finalize based on mTrackNum
		const mkvparser::CuePoint::TrackPosition* pTP;
		if (pTrack) {
		if (pTrack && pTrack->GetType() == 1) {
		pCues->Find(seekTimeNs, pTrack, pCP, pTP);
		} else {
		ALOGE("Did not locate a VIDEO_TRACK");
		ALOGE("Did not locate the video track for seeking");
		return;
		}

		mCluster = pSegment->FindOrPreloadCluster(pTP->m_pos);
		if (pTP->m_block > 0) {
		// m_block starts at 1, but mBlockEntryIndex is expected to start at 0
		mBlockEntryIndex = pTP->m_block - 1;
		} else {
		ALOGE("m_block must be > 0");
		return;
		}

		long prevKeyFrameBlockEntryIndex = -1;
		CHECK(mCluster);
		CHECK(!mCluster->EOS());

		// mBlockEntryIndex starts at 0 but m_block starts at 1
		CHECK_GT(pTP->m_block, 0);
		mBlockEntryIndex = pTP->m_block - 1;

		for (;;) {
		advance_l();

		if (eos()) {
		break;
		}

		if (block()->GetTrackNumber() != mTrackNum) {
		continue;
		}

		if (block()->IsKey()) {
		prevKeyFrameBlockEntryIndex = mBlockEntryIndex - 1;
		}
		if (eos()) break;

		int64_t timeNs = block()->GetTime(mCluster);

		if (timeNs >= seekTimeNs) {
		*actualFrameTimeUs = (timeNs + 500ll) / 1000ll;
		if (isAudio \|\| block()->IsKey()) {
		// Accept the first key frame
		*actualFrameTimeUs = (block()->GetTime(mCluster) + 500LL) / 1000LL;
		ALOGV("Requested seek point: %lld actual: %lld",
		seekTimeUs, actualFrameTimeUs);
		break;
		}
		}

		if (eos()) {
		return;
		}

		if (seekToKeyFrame && !block()->IsKey()) {
		CHECK_GE(prevKeyFrameBlockEntryIndex, 0);
		mBlockEntryIndex = prevKeyFrameBlockEntryIndex;
		advance_l();
		}
		}

		const mkvparser::Block *BlockIterator::block() const {
		@@ -521,11 +499,11 @@ status_t MatroskaSource::read(
		&& !mExtractor->isLiveStreaming()) {
		clearPendingFrames();

		// Apparently keyframe indication in audio tracks is unreliable,
		// fortunately in all our currently supported audio encodings every
		// frame is effectively a keyframe.
		// The audio we want is located by using the Cues to seek the video
		// stream to find the target Cluster then iterating to finalize for
		// audio.
		int64_t actualFrameTimeUs;
		mBlockIter.seek(seekTimeUs, !mIsAudio, &actualFrameTimeUs);
		mBlockIter.seek(seekTimeUs, mIsAudio, &actualFrameTimeUs);

		if (mode == ReadOptions::SEEK_CLOSEST) {
		targetSampleTimeUs = actualFrameTimeUs;