Merge "Offset direct/offload timestamps by downstream latency" (2d8a0e22) · Commits · e / os / android_frameworks_av

services/audioflinger/Threads.cpp

+14 −6

Original line number	Diff line number	Diff line
		@@ -3185,7 +3185,6 @@ bool AudioFlinger::PlaybackThread::threadLoop()
		if (mType == OFFLOAD \|\| mType == DIRECT) {
		mTimestampVerifier.setDiscontinuityMode(mTimestampVerifier.DISCONTINUITY_MODE_ZERO);
		}
		audio_utils::Statistics<double> downstreamLatencyStatMs(0.999 /* alpha */);
		audio_patch_handle_t lastDownstreamPatchHandle = AUDIO_PATCH_HANDLE_NONE;

		while (!exitPending())
		@@ -3215,7 +3214,7 @@ bool AudioFlinger::PlaybackThread::threadLoop()
		downstreamPatchHandle = swPatches[0].getPatchHandle();
		}
		if (downstreamPatchHandle != lastDownstreamPatchHandle) {
		downstreamLatencyStatMs.reset();
		mDownstreamLatencyStatMs.reset();
		lastDownstreamPatchHandle = downstreamPatchHandle;
		}
		if (status == OK) {
		@@ -3229,14 +3228,14 @@ bool AudioFlinger::PlaybackThread::threadLoop()
		if (latencyMs < minLatency) latencyMs = minLatency;
		else if (latencyMs > maxLatency) latencyMs = maxLatency;
		}
		downstreamLatencyStatMs.add(latencyMs);
		mDownstreamLatencyStatMs.add(latencyMs);
		}
		mAudioFlinger->mLock.unlock();
		}
		} else {
		if (lastDownstreamPatchHandle != AUDIO_PATCH_HANDLE_NONE) {
		// our device is no longer AUDIO_DEVICE_OUT_BUS, reset patch handle and stats.
		downstreamLatencyStatMs.reset();
		mDownstreamLatencyStatMs.reset();
		lastDownstreamPatchHandle = AUDIO_PATCH_HANDLE_NONE;
		}
		}
		@@ -3285,10 +3284,10 @@ bool AudioFlinger::PlaybackThread::threadLoop()
		(long long)timestamp.mPosition[ExtendedTimestamp::LOCATION_KERNEL]);

		// Note: Downstream latency only added if timestamp correction enabled.
		if (downstreamLatencyStatMs.getN() > 0) { // we have latency info.
		if (mDownstreamLatencyStatMs.getN() > 0) { // we have latency info.
		const int64_t newPosition =
		timestamp.mPosition[ExtendedTimestamp::LOCATION_KERNEL]
		- int64_t(downstreamLatencyStatMs.getMean() * mSampleRate * 1e-3);
		- int64_t(mDownstreamLatencyStatMs.getMean() * mSampleRate * 1e-3);
		// prevent retrograde
		timestamp.mPosition[ExtendedTimestamp::LOCATION_KERNEL] = max(
		newPosition,
		@@ -3747,6 +3746,15 @@ status_t AudioFlinger::PlaybackThread::getTimestamp_l(AudioTimestamp& timestamp)
		uint64_t position64;
		if (mOutput->getPresentationPosition(&position64, &timestamp.mTime) == OK) {
		timestamp.mPosition = (uint32_t)position64;
		if (mDownstreamLatencyStatMs.getN() > 0) {
		const uint32_t positionOffset =
		(uint32_t)(mDownstreamLatencyStatMs.getMean() * mSampleRate * 1e-3);
		if (positionOffset > timestamp.mPosition) {
		timestamp.mPosition = 0;
		} else {
		timestamp.mPosition -= positionOffset;
		}
		}
		return NO_ERROR;
		}
		}

services/audioflinger/Threads.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -1082,6 +1082,8 @@ private:
		static const size_t kFastMixerLogSize = 8 * 1024;
		sp<NBLog::Writer> mFastMixerNBLogWriter;

		// Downstream patch latency, available if mDownstreamLatencyStatMs.getN() > 0.
		audio_utils::Statistics<double> mDownstreamLatencyStatMs{0.999};

		public:
		virtual bool hasFastMixer() const = 0;