stagefright: Fix seeking in MPEG4 container (599950ef) · Commits · e / os / android_frameworks_av

media/libstagefright/MPEG4Extractor.cpp

+1 −1

Original line number	Diff line number	Diff line
		@@ -3665,7 +3665,7 @@ status_t MPEG4Source::read(

		uint32_t sampleIndex;
		status_t err = mSampleTable->findSampleAtTime(
		seekTimeUs * mTimescale / 1000000,
		seekTimeUs, 1000000, mTimescale,
		&sampleIndex, findFlags);

		if (mode == ReadOptions::SEEK_CLOSEST) {

media/libstagefright/OggExtractor.cpp

+4 −4

Original line number	Diff line number	Diff line
		@@ -320,14 +320,14 @@ status_t MyVorbisExtractor::seekToTime(int64_t timeUs) {
		}

		size_t left = 0;
		size_t right = mTableOfContents.size();
		while (left < right) {
		size_t center = left / 2 + right / 2 + (left & right & 1);
		size_t right = mTableOfContents.size() - 1;
		while (left <= right) {
		size_t center = left + (right - left) / 2;

		const TOCEntry &entry = mTableOfContents.itemAt(center);

		if (timeUs < entry.mTimeUs) {
		right = center;
		right = center - 1;
		} else if (timeUs > entry.mTimeUs) {
		left = center + 1;
		} else {

media/libstagefright/SampleTable.cpp

+77 −112

Original line number	Diff line number	Diff line
		@@ -520,83 +520,72 @@ void SampleTable::buildSampleEntriesTable() {
		}

		status_t SampleTable::findSampleAtTime(
		uint32_t req_time, uint32_t *sample_index, uint32_t flags) {
		uint64_t req_time, uint64_t scale_num, uint64_t scale_den,
		uint32_t *sample_index, uint32_t flags) {
		buildSampleEntriesTable();

		uint32_t left = 0;
		uint32_t right = mNumSampleSizes;
		while (left < right) {
		uint32_t center = (left + right) / 2;
		uint32_t centerTime = mSampleTimeEntries[center].mCompositionTime;
		uint32_t right = mNumSampleSizes - 1;
		while (left <= right) {
		uint32_t center = left + (right - left) / 2;
		uint64_t centerTime =
		getSampleTime(center, scale_num, scale_den);

		if (req_time < centerTime) {
		right = center;
		right = center - 1;
		} else if (req_time > centerTime) {
		left = center + 1;
		} else {
		left = center;
		break;
		*sample_index = mSampleTimeEntries[center].mSampleIndex;
		return OK;
		}
		}

		if (left == mNumSampleSizes) {
		uint32_t closestIndex = left;

		if (closestIndex == mNumSampleSizes) {
		if (flags == kFlagAfter) {
		return ERROR_OUT_OF_RANGE;
		}

		--left;
		flags = kFlagBefore;
		} else if (closestIndex == 0) {
		if (flags == kFlagBefore) {
		// normally we should return out of range, but that is
		// treated as end-of-stream. instead return first sample
		//
		// return ERROR_OUT_OF_RANGE;
		}
		flags = kFlagAfter;
		}

		uint32_t closestIndex = left;

		switch (flags) {
		case kFlagBefore:
		{
		while (closestIndex > 0
		&& mSampleTimeEntries[closestIndex].mCompositionTime
		> req_time) {
		--closestIndex;
		}
		break;
		}

		case kFlagAfter:
		{
		while (closestIndex + 1 < mNumSampleSizes
		&& mSampleTimeEntries[closestIndex].mCompositionTime
		< req_time) {
		++closestIndex;
		}
		// nothing to do
		break;
		}

		default:
		{
		CHECK(flags == kFlagClosest);

		if (closestIndex > 0) {
		// Check left neighbour and pick closest.
		uint32_t absdiff1 =
		// pick closest based on timestamp. use abs_difference for safety
		if (abs_difference(
		getSampleTime(closestIndex, scale_num, scale_den), req_time) >
		abs_difference(
		mSampleTimeEntries[closestIndex].mCompositionTime,
		req_time);

		uint32_t absdiff2 =
		abs_difference(
		mSampleTimeEntries[closestIndex - 1].mCompositionTime,
		req_time);

		if (absdiff1 > absdiff2) {
		closestIndex = closestIndex - 1;
		}
		req_time, getSampleTime(closestIndex - 1, scale_num, scale_den))) {
		--closestIndex;
		}

		break;
		}
		}

		*sample_index = mSampleTimeEntries[closestIndex].mSampleIndex;

		return OK;
		}

		@@ -618,109 +607,85 @@ status_t SampleTable::findSyncSampleNear(
		}

		uint32_t left = 0;
		uint32_t right = mNumSyncSamples;
		while (left < right) {
		uint32_t right = mNumSyncSamples - 1;
		while (left <= right) {
		uint32_t center = left + (right - left) / 2;
		uint32_t x = mSyncSamples[center];

		if (start_sample_index < x) {
		right = center;
		right = center - 1;
		} else if (start_sample_index > x) {
		left = center + 1;
		} else {
		left = center;
		break;
		*sample_index = x;
		return OK;
		}
		}

		if (left == mNumSyncSamples) {
		if (flags == kFlagAfter) {
		ALOGE("tried to find a sync frame after the last one: %d", left);
		return ERROR_OUT_OF_RANGE;
		}
		left = left - 1;
		flags = kFlagBefore;
		}
		else if (left == 0) {
		if (flags == kFlagBefore) {
		ALOGE("tried to find a sync frame before the first one: %d", left);

		// Now ssi[left] is the sync sample index just before (or at)
		// start_sample_index.
		// Also start_sample_index < ssi[left + 1], if left + 1 < mNumSyncSamples.

		uint32_t x = mSyncSamples[left];

		if (left + 1 < mNumSyncSamples) {
		uint32_t y = mSyncSamples[left + 1];
		// normally we should return out of range, but that is
		// treated as end-of-stream. instead seek to first sync
		//
		// return ERROR_OUT_OF_RANGE;
		}
		flags = kFlagAfter;
		}

		// our sample lies between sync samples x and y.
		// Now ssi[left - 1] <(=) start_sample_index <= ssi[left]
		switch (flags) {
		case kFlagBefore:
		{
		--left;
		break;
		}
		case kFlagAfter:
		{
		// nothing to do
		break;
		}
		default:
		{
		// this route is not used, but implement it nonetheless
		CHECK(flags == kFlagClosest);

		status_t err = mSampleIterator->seekTo(start_sample_index);
		if (err != OK) {
		return err;
		}

		uint32_t sample_time = mSampleIterator->getSampleTime();

		err = mSampleIterator->seekTo(x);
		err = mSampleIterator->seekTo(mSyncSamples[left]);
		if (err != OK) {
		return err;
		}
		uint32_t x_time = mSampleIterator->getSampleTime();
		uint32_t upper_time = mSampleIterator->getSampleTime();

		err = mSampleIterator->seekTo(y);
		err = mSampleIterator->seekTo(mSyncSamples[left - 1]);
		if (err != OK) {
		return err;
		}
		uint32_t lower_time = mSampleIterator->getSampleTime();

		uint32_t y_time = mSampleIterator->getSampleTime();

		if (abs_difference(x_time, sample_time)
		> abs_difference(y_time, sample_time)) {
		// Pick the sync sample closest (timewise) to the start-sample.
		x = y;
		++left;
		}
		}

		switch (flags) {
		case kFlagBefore:
		{
		if (x > start_sample_index) {
		CHECK(left > 0);

		x = mSyncSamples[left - 1];

		if (x > start_sample_index) {
		// The table of sync sample indices was not sorted
		// properly.
		return ERROR_MALFORMED;
		}
		}
		break;
		}

		case kFlagAfter:
		{
		if (x < start_sample_index) {
		if (left + 1 >= mNumSyncSamples) {
		return ERROR_OUT_OF_RANGE;
		}

		x = mSyncSamples[left + 1];

		if (x < start_sample_index) {
		// The table of sync sample indices was not sorted
		// properly.
		return ERROR_MALFORMED;
		}
		// use abs_difference for safety
		if (abs_difference(upper_time, sample_time) >
		abs_difference(sample_time, lower_time)) {
		--left;
		}

		break;
		}

		default:
		break;
		}

		*sample_index = x;

		*sample_index = mSyncSamples[left];
		return OK;
		}

media/libstagefright/include/SampleTable.h

+9 −1

Original line number	Diff line number	Diff line
		@@ -75,7 +75,8 @@ public:
		kFlagClosest
		};
		status_t findSampleAtTime(
		uint32_t req_time, uint32_t *sample_index, uint32_t flags);
		uint64_t req_time, uint64_t scale_num, uint64_t scale_den,
		uint32_t *sample_index, uint32_t flags);

		status_t findSyncSampleNear(
		uint32_t start_sample_index, uint32_t *sample_index,
		@@ -138,6 +139,13 @@ private:

		friend struct SampleIterator;

		// normally we don't round
		inline uint64_t getSampleTime(
		size_t sample_index, uint64_t scale_num, uint64_t scale_den) const {
		return (mSampleTimeEntries[sample_index].mCompositionTime
		* scale_num) / scale_den;
		}

		status_t getSampleSize_l(uint32_t sample_index, size_t *sample_size);
		uint32_t getCompositionTimeOffset(uint32_t sampleIndex);