Merge "Improve AudioTrack EVENT_LOOP_END and EVENT_BUFFER_END accuracy" (bb67a2e8) · Commits · e / os / android_frameworks_av

include/media/AudioTrack.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -736,6 +736,10 @@ protected:
		int32_t mLoopCount; // last setLoop loopCount; zero means disabled
		uint32_t mLoopStart; // last setLoop loopStart
		uint32_t mLoopEnd; // last setLoop loopEnd
		int32_t mLoopCountNotified; // the last loopCount notified by callback.
		// mLoopCountNotified counts down, matching
		// the remaining loop count for static track
		// playback.

		// These are private to processAudioBuffer(), and are not protected by a lock
		uint32_t mRemainingFrames; // number of frames to request in obtainBuffer()

media/libmedia/AudioTrack.cpp

+40 −11

Original line number	Diff line number	Diff line
		@@ -33,7 +33,7 @@

		#define WAIT_PERIOD_MS 10
		#define WAIT_STREAM_END_TIMEOUT_SEC 120

		static const int kMaxLoopCountNotifications = 32;

		namespace android {
		// ---------------------------------------------------------------------------
		@@ -428,6 +428,7 @@ status_t AudioTrack::set(
		mLoopCount = 0;
		mLoopStart = 0;
		mLoopEnd = 0;
		mLoopCountNotified = 0;
		mMarkerPosition = 0;
		mMarkerReached = false;
		mNewPosition = 0;
		@@ -750,6 +751,7 @@ void AudioTrack::setLoop_l(uint32_t loopStart, uint32_t loopEnd, int loopCount)
		mLoopCount = loopCount;
		mLoopEnd = loopEnd;
		mLoopStart = loopStart;
		mLoopCountNotified = loopCount;
		mStaticProxy->setLoop(loopStart, loopEnd, loopCount);
		}

		@@ -899,10 +901,15 @@ status_t AudioTrack::reload()
		mNewPosition = mUpdatePeriod;
		(void) updateAndGetPosition_l();
		mPosition = 0;
		#if 0
		// The documentation is not clear on the behavior of reload() and the restoration
		// of loop count. Historically we have not restored loop count, start, end;
		// rather we just reset the buffer position. However, restoring the last setLoop
		// information makes sense if one desires to repeat playing a particular sound.
		// of loop count. Historically we have not restored loop count, start, end,
		// but it makes sense if one desires to repeat playing a particular sound.
		if (mLoopCount != 0) {
		mLoopCountNotified = mLoopCount;
		mStaticProxy->setLoop(mLoopStart, mLoopEnd, mLoopCount);
		}
		#endif
		mStaticProxy->setBufferPosition(0);
		return NO_ERROR;
		}
		@@ -1566,9 +1573,8 @@ nsecs_t AudioTrack::processAudioBuffer()
		// that the upper layers can recreate the track
		if (!isOffloadedOrDirect_l() \|\| (mSequence == mObservedSequence)) {
		status_t status = restoreTrack_l("processAudioBuffer");
		mLock.unlock();
		// Run again immediately, but with a new IAudioTrack
		return 0;
		// after restoration, continue below to make sure that the loop and buffer events
		// are notified because they have been cleared from mCblk->mFlags above.
		}
		}

		@@ -1617,7 +1623,6 @@ nsecs_t AudioTrack::processAudioBuffer()
		}

		// Cache other fields that will be needed soon
		uint32_t loopPeriod = mLoopCount != 0 ? mLoopEnd - mLoopStart : 0;
		uint32_t sampleRate = mSampleRate;
		uint32_t notificationFrames = mNotificationFramesAct;
		if (mRefreshRemaining) {
		@@ -1629,6 +1634,28 @@ nsecs_t AudioTrack::processAudioBuffer()
		uint32_t sequence = mSequence;
		sp<AudioTrackClientProxy> proxy = mProxy;

		// Determine the number of new loop callback(s) that will be needed, while locked.
		int loopCountNotifications = 0;
		uint32_t loopPeriod = 0; // time in frames for next EVENT_LOOP_END or EVENT_BUFFER_END

		if (mLoopCount > 0) {
		int loopCount;
		size_t bufferPosition;
		mStaticProxy->getBufferPositionAndLoopCount(&bufferPosition, &loopCount);
		loopPeriod = ((loopCount > 0) ? mLoopEnd : mFrameCount) - bufferPosition;
		loopCountNotifications = min(mLoopCountNotified - loopCount, kMaxLoopCountNotifications);
		mLoopCountNotified = loopCount; // discard any excess notifications
		} else if (mLoopCount < 0) {
		// FIXME: We're not accurate with notification count and position with infinite looping
		// since loopCount from server side will always return -1 (we could decrement it).
		size_t bufferPosition = mStaticProxy->getBufferPosition();
		loopCountNotifications = int((flags & (CBLK_LOOP_CYCLE \| CBLK_LOOP_FINAL)) != 0);
		loopPeriod = mLoopEnd - bufferPosition;
		} else if (/* mLoopCount == 0 && */ mSharedBuffer != 0) {
		size_t bufferPosition = mStaticProxy->getBufferPosition();
		loopPeriod = mFrameCount - bufferPosition;
		}

		// These fields don't need to be cached, because they are assigned only by set():
		// mTransfer, mCbf, mUserData, mFormat, mFrameSize, mFrameSizeAF, mFlags
		// mFlags is also assigned by createTrack_l(), but not the bit we care about.
		@@ -1669,10 +1696,9 @@ nsecs_t AudioTrack::processAudioBuffer()
		if (newUnderrun) {
		mCbf(EVENT_UNDERRUN, mUserData, NULL);
		}
		// FIXME we will miss loops if loop cycle was signaled several times since last call
		// to processAudioBuffer()
		if (flags & (CBLK_LOOP_CYCLE \| CBLK_LOOP_FINAL)) {
		while (loopCountNotifications > 0) {
		mCbf(EVENT_LOOP_END, mUserData, NULL);
		--loopCountNotifications;
		}
		if (flags & CBLK_BUFFER_END) {
		mCbf(EVENT_BUFFER_END, mUserData, NULL);
		@@ -1891,6 +1917,9 @@ status_t AudioTrack::restoreTrack_l(const char *from)
		mLoopStart, mLoopEnd, loopCount);
		} else {
		mStaticProxy->setBufferPosition(bufferPosition);
		if (bufferPosition == mFrameCount) {
		ALOGD("restoring track at end of static buffer");
		}
		}
		}
		if (mState == STATE_ACTIVE) {