Merge "Allow edit list atom to appear earlier in the file" (f64fa712) · Commits · e / os / android_frameworks_av

media/libstagefright/MPEG4Extractor.cpp

+71 −27

Original line number	Diff line number	Diff line
		@@ -463,6 +463,66 @@ sp<MetaData> MPEG4Extractor::getTrackMetaData(
		return NULL;
		}

		int64_t duration;
		int32_t samplerate;
		if (track->has_elst && mHeaderTimescale != 0 &&
		track->meta->findInt64(kKeyDuration, &duration) &&
		track->meta->findInt32(kKeySampleRate, &samplerate)) {

		track->has_elst = false;

		if (track->elst_segment_duration > INT64_MAX) {
		goto editlistoverflow;
		}
		int64_t segment_duration = track->elst_segment_duration;
		int64_t media_time = track->elst_media_time;
		int64_t halfscale = mHeaderTimescale / 2;

		int64_t delay;
		// delay = ((media_time * samplerate) + halfscale) / mHeaderTimescale;
		if (__builtin_mul_overflow(media_time, samplerate, &delay) \|\|
		__builtin_add_overflow(delay, halfscale, &delay) \|\|
		(delay /= mHeaderTimescale, false) \|\|
		delay > INT32_MAX \|\|
		delay < INT32_MIN) {
		goto editlistoverflow;
		}
		track->meta->setInt32(kKeyEncoderDelay, delay);

		int64_t scaled_duration;
		// scaled_duration = ((duration * mHeaderTimescale) + 500000) / 1000000;
		if (__builtin_mul_overflow(duration, mHeaderTimescale, &scaled_duration) \|\|
		__builtin_add_overflow(scaled_duration, 500000, &scaled_duration)) {
		goto editlistoverflow;
		}
		scaled_duration /= 1000000;

		int64_t segment_end;
		int64_t padding;
		if (__builtin_add_overflow(segment_duration, media_time, &segment_end) \|\|
		__builtin_sub_overflow(scaled_duration, segment_end, &padding)) {
		goto editlistoverflow;
		}

		if (padding < 0) {
		// track duration from media header (which is what kKeyDuration is) might
		// be slightly shorter than the segment duration, which would make the
		// padding negative. Clamp to zero.
		padding = 0;
		}

		int64_t paddingsamples;
		// paddingsamples = ((padding * samplerate) + halfscale) / mHeaderTimescale;
		if (__builtin_mul_overflow(padding, samplerate, &paddingsamples) \|\|
		__builtin_add_overflow(paddingsamples, halfscale, &paddingsamples) \|\|
		(paddingsamples /= mHeaderTimescale, false) \|\|
		paddingsamples > INT32_MAX) {
		goto editlistoverflow;
		}
		track->meta->setInt32(kKeyEncoderPadding, paddingsamples);
		}
		editlistoverflow:

		if ((flags & kIncludeExtensiveMetaData)
		&& !track->includes_expensive_metadata) {
		track->includes_expensive_metadata = true;
		@@ -995,6 +1055,7 @@ status_t MPEG4Extractor::parseChunk(off64_t *offset, int depth) {
		track->skipTrack = false;
		track->timescale = 0;
		track->meta->setCString(kKeyMIMEType, "application/octet-stream");
		track->has_elst = false;
		}

		off64_t stop_offset = *offset + chunk_size;
		@@ -1061,6 +1122,10 @@ status_t MPEG4Extractor::parseChunk(off64_t *offset, int depth) {
		{
		*offset += chunk_size;

		if (!mLastTrack) {
		return ERROR_MALFORMED;
		}

		// See 14496-12 8.6.6
		uint8_t version;
		if (mDataSource->readAt(data_offset, &version, 1) < 1) {
		@@ -1075,8 +1140,6 @@ status_t MPEG4Extractor::parseChunk(off64_t *offset, int depth) {
		if (entry_count != 1) {
		// we only support a single entry at the moment, for gapless playback
		ALOGW("ignoring edit list with %d entries", entry_count);
		} else if (mHeaderTimescale == 0) {
		ALOGW("ignoring edit list because timescale is 0");
		} else {
		off64_t entriesoffset = data_offset + 8;
		uint64_t segment_duration;
		@@ -1100,31 +1163,12 @@ status_t MPEG4Extractor::parseChunk(off64_t *offset, int depth) {
		return ERROR_IO;
		}

		uint64_t halfscale = mHeaderTimescale / 2;
		segment_duration = (segment_duration * 1000000 + halfscale)/ mHeaderTimescale;
		media_time = (media_time * 1000000 + halfscale) / mHeaderTimescale;

		int64_t duration;
		int32_t samplerate;
		if (!mLastTrack) {
		return ERROR_MALFORMED;
		}
		if (mLastTrack->meta->findInt64(kKeyDuration, &duration) &&
		mLastTrack->meta->findInt32(kKeySampleRate, &samplerate)) {

		int64_t delay = (media_time * samplerate + 500000) / 1000000;
		mLastTrack->meta->setInt32(kKeyEncoderDelay, delay);

		int64_t paddingus = duration - (int64_t)(segment_duration + media_time);
		if (paddingus < 0) {
		// track duration from media header (which is what kKeyDuration is) might
		// be slightly shorter than the segment duration, which would make the
		// padding negative. Clamp to zero.
		paddingus = 0;
		}
		int64_t paddingsamples = (paddingus * samplerate + 500000) / 1000000;
		mLastTrack->meta->setInt32(kKeyEncoderPadding, paddingsamples);
		}
		// save these for later, because the elst atom might precede
		// the atoms that actually gives us the duration and sample rate
		// needed to calculate the padding and delay values
		mLastTrack->has_elst = true;
		mLastTrack->elst_media_time = media_time;
		mLastTrack->elst_segment_duration = segment_duration;
		}
		break;
		}

media/libstagefright/include/MPEG4Extractor.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -82,6 +82,9 @@ private:
		sp<SampleTable> sampleTable;
		bool includes_expensive_metadata;
		bool skipTrack;
		bool has_elst;
		int64_t elst_media_time;
		uint64_t elst_segment_duration;
		};

		Vector<SidxEntry> mSidxEntries;