Merge \"stagefright: prefer B frames for high frame-rate recording\" into nyc-mr1-dev (78ef3296) · Commits · e / os / android_frameworks_av

media/libmediaplayerservice/StagefrightRecorder.cpp

+7 −0

Original line number	Diff line number	Diff line
		@@ -1573,6 +1573,7 @@ status_t StagefrightRecorder::setupVideoEncoder(
		}

		uint32_t tsLayers = 1;
		bool preferBFrames = true; // we like B-frames as it produces better quality per bitrate
		format->setInt32("priority", 0 /* realtime */);
		float maxPlaybackFps = mFrameRate; // assume video is only played back at normal speed

		@@ -1581,9 +1582,11 @@ status_t StagefrightRecorder::setupVideoEncoder(

		// enable layering for all time lapse and high frame rate recordings
		if (mFrameRate / mCaptureFps >= 1.9) { // time lapse
		preferBFrames = false;
		tsLayers = 2; // use at least two layers as resulting video will likely be sped up
		} else if (mCaptureFps > maxPlaybackFps) { // slow-mo
		maxPlaybackFps = mCaptureFps; // assume video will be played back at full capture speed
		preferBFrames = false;
		}
		}

		@@ -1603,6 +1606,10 @@ status_t StagefrightRecorder::setupVideoEncoder(
		uint32_t pLayers = tsLayers - bLayers;
		format->setString(
		"ts-schema", AStringPrintf("android.generic.%u+%u", pLayers, bLayers));

		// TODO: some encoders do not support B-frames with temporal layering, and we have a
		// different preference based on use-case. We could move this into camera profiles.
		format->setInt32("android._prefer-b-frames", preferBFrames);
		}

		if (mMetaDataStoredInVideoBuffers != kMetadataBufferTypeInvalid) {

+28 −0

Original line number	Diff line number	Diff line
		@@ -4343,6 +4343,34 @@ status_t ACodec::setupAVCEncoderParameters(const sp<AMessage> &msg) {
		return err;
		}

		// TRICKY: if we are enabling temporal layering as well, some codecs may not support layering
		// when B-frames are enabled. Detect this now so we can disable B frames if temporal layering
		// is preferred.
		AString tsSchema;
		int32_t preferBFrames = (int32_t)false;
		if (msg->findString("ts-schema", &tsSchema)
		&& (!msg->findInt32("android._prefer-b-frames", &preferBFrames) \|\| !preferBFrames)) {
		OMX_VIDEO_PARAM_ANDROID_TEMPORALLAYERINGTYPE layering;
		InitOMXParams(&layering);
		layering.nPortIndex = kPortIndexOutput;
		if (mOMX->getParameter(
		mNode, (OMX_INDEXTYPE)OMX_IndexParamAndroidVideoTemporalLayering,
		&layering, sizeof(layering)) == OK
		&& layering.eSupportedPatterns
		&& layering.nBLayerCountMax == 0) {
		h264type.nBFrames = 0;
		h264type.nPFrames = setPFramesSpacing(iFrameInterval, frameRate, h264type.nBFrames);
		h264type.nAllowedPictureTypes &= ~OMX_VIDEO_PictureTypeB;
		ALOGI("disabling B-frames");
		err = mOMX->setParameter(
		mNode, OMX_IndexParamVideoAvc, &h264type, sizeof(h264type));

		if (err != OK) {
		return err;
		}
		}
		}

		return configureBitrate(bitrate, bitrateMode);
		}