Merge "Improve AudioTrack offload timestamp startup glitch detector" into mnc-dev (81c4d806) · Commits · e / os / android_frameworks_av

include/media/AudioTrack.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -894,6 +894,7 @@ protected:
		// only used for offloaded and direct tracks.

		bool mPreviousTimestampValid;// true if mPreviousTimestamp is valid
		bool mTimestampStartupGlitchReported; // reduce log spam
		bool mRetrogradeMotionReported; // reduce log spam
		AudioTimestamp mPreviousTimestamp; // used to detect retrograde motion

media/libmedia/AudioTrack.cpp

+26 −4

Original line number	Diff line number	Diff line
		@@ -492,6 +492,8 @@ status_t AudioTrack::set(
		mObservedSequence = mSequence;
		mInUnderrun = false;
		mPreviousTimestampValid = false;
		mTimestampStartupGlitchReported = false;
		mRetrogradeMotionReported = false;

		return NO_ERROR;
		}
		@@ -519,6 +521,8 @@ status_t AudioTrack::start()
		// reset current position as seen by client to 0
		mPosition = 0;
		mPreviousTimestampValid = false;
		mTimestampStartupGlitchReported = false;
		mRetrogradeMotionReported = false;

		// For offloaded tracks, we don't know if the hardware counters are really zero here,
		// since the flush is asynchronous and stop may not fully drain.
		@@ -2218,7 +2222,12 @@ status_t AudioTrack::getTimestamp(AudioTimestamp& timestamp)
		}

		// Check whether a pending flush or stop has completed, as those commands may
		// be asynchronous or return near finish.
		// be asynchronous or return near finish or exhibit glitchy behavior.
		//
		// Originally this showed up as the first timestamp being a continuation of
		// the previous song under gapless playback.
		// However, we sometimes see zero timestamps, then a glitch of
		// the previous song's position, and then correct timestamps afterwards.
		if (mStartUs != 0 && mSampleRate != 0) {
		static const int kTimeJitterUs = 100000; // 100 ms
		static const int k1SecUs = 1000000;
		@@ -2236,16 +2245,29 @@ status_t AudioTrack::getTimestamp(AudioTimestamp& timestamp)

		if (deltaPositionByUs > deltaTimeUs + kTimeJitterUs) {
		// Verify that the counter can't count faster than the sample rate
		// since the start time. If greater, then that means we have failed
		// since the start time. If greater, then that means we may have failed
		// to completely flush or stop the previous playing track.
		ALOGW("incomplete flush or stop:"
		ALOGW_IF(!mTimestampStartupGlitchReported,
		"getTimestamp startup glitch detected"
		" deltaTimeUs(%lld) deltaPositionUs(%lld) tsmPosition(%u)",
		(long long)deltaTimeUs, (long long)deltaPositionByUs,
		timestamp.mPosition);
		mTimestampStartupGlitchReported = true;
		if (previousTimestampValid
		&& mPreviousTimestamp.mPosition == 0 /* should be true if valid */) {
		timestamp = mPreviousTimestamp;
		mPreviousTimestampValid = true;
		return NO_ERROR;
		}
		return WOULD_BLOCK;
		}
		if (deltaPositionByUs != 0) {
		mStartUs = 0; // don't check again, we got valid nonzero position.
		}
		} else {
		mStartUs = 0; // don't check again, start time expired.
		}
		mStartUs = 0; // no need to check again, start timestamp has either expired or unneeded.
		mTimestampStartupGlitchReported = false;
		}
		} else {
		// Update the mapping between local consumed (mPosition) and server consumed (mServer)