Merge "Another attempt for fixing AAC+/eAAC+ related issue" into gingerbread (e5206694) · Commits · e / os / android_frameworks_base

media/libstagefright/codecs/aacdec/AACDecoder.cpp

+57 −12

Original line number	Diff line number	Diff line
		@@ -123,6 +123,8 @@ status_t AACDecoder::start(MetaData *params) {
		mAnchorTimeUs = 0;
		mNumSamplesOutput = 0;
		mStarted = true;
		mNumDecodedBuffers = 0;
		mUpsamplingFactor = 2;

		return OK;
		}
		@@ -207,22 +209,65 @@ status_t AACDecoder::read(

		Int decoderErr = PVMP4AudioDecodeFrame(mConfig, mDecoderBuf);

		/*
		* AAC+/eAAC+ streams can be signalled in two ways: either explicitly
		* or implicitly, according to MPEG4 spec. AAC+/eAAC+ is a dual
		* rate system and the sampling rate in the final output is actually
		* doubled compared with the core AAC decoder sampling rate.
		*
		* Explicit signalling is done by explicitly defining SBR audio object
		* type in the bitstream. Implicit signalling is done by embedding
		* SBR content in AAC extension payload specific to SBR, and hence
		* requires an AAC decoder to perform pre-checks on actual audio frames.
		*
		* Thus, we could not say for sure whether a stream is
		* AAC+/eAAC+ until the first data frame is decoded.
		*/
		if (++mNumDecodedBuffers <= 2) {
		LOGV("audio/extended audio object type: %d + %d",
		mConfig->audioObjectType, mConfig->extendedAudioObjectType);
		LOGV("aac+ upsampling factor: %d desired channels: %d",
		mConfig->aacPlusUpsamplingFactor, mConfig->desiredChannels);

		CHECK(mNumDecodedBuffers > 0);
		if (mNumDecodedBuffers == 1) {
		mUpsamplingFactor = mConfig->aacPlusUpsamplingFactor;
		// Check on the sampling rate to see whether it is changed.
		int32_t sampleRate;
		CHECK(mMeta->findInt32(kKeySampleRate, &sampleRate));
		if (mConfig->samplingRate != sampleRate) {
		mMeta->setInt32(kKeySampleRate, mConfig->samplingRate);
		LOGW("Sample rate was %d, but now is %d",
		LOGW("Sample rate was %d Hz, but now is %d Hz",
		sampleRate, mConfig->samplingRate);
		buffer->release();
		mInputBuffer->release();
		mInputBuffer = NULL;
		return INFO_FORMAT_CHANGED;
		}
		} else { // mNumDecodedBuffers == 2
		if (mConfig->extendedAudioObjectType == MP4AUDIO_AAC_LC \|\|
		mConfig->extendedAudioObjectType == MP4AUDIO_LTP) {
		if (mUpsamplingFactor == 2) {
		// The stream turns out to be not aacPlus mode anyway
		LOGW("Disable AAC+/eAAC+ since extended audio object type is %d",
		mConfig->extendedAudioObjectType);
		mConfig->aacPlusEnabled = 0;
		}
		} else {
		if (mUpsamplingFactor == 1) {
		// aacPlus mode does not buy us anything, but to cause
		// 1. CPU load to increase, and
		// 2. a half speed of decoding
		LOGW("Disable AAC+/eAAC+ since upsampling factor is 1");
		mConfig->aacPlusEnabled = 0;
		}
		}
		}
		}

		size_t numOutBytes =
		mConfig->frameLength * sizeof(int16_t) * mConfig->desiredChannels;
		if (mConfig->aacPlusUpsamplingFactor == 2) {
		if (mUpsamplingFactor == 2) {
		if (mConfig->desiredChannels == 1) {
		memcpy(&mConfig->pOutputBuffer[1024], &mConfig->pOutputBuffer[2048], numOutBytes * 2);
		}

media/libstagefright/include/AACDecoder.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -53,6 +53,8 @@ private:
		int64_t mAnchorTimeUs;
		int64_t mNumSamplesOutput;
		status_t mInitCheck;
		int64_t mNumDecodedBuffers;
		int32_t mUpsamplingFactor;

		MediaBuffer *mInputBuffer;