Phase 7

apps/LoopThroughWithOpenGLCompositing/videoio/VideoPlayoutScheduler.cpp

@@ -16,6 +16,9 @@ void VideoPlayoutScheduler::Configure(int64_t frameDuration, int64_t timeScale,
 void VideoPlayoutScheduler::Reset()
 {
 	mScheduledFrameIndex = 0;
+	mCompletedFrameIndex = 0;
+	mLateStreak = 0;
+	mDropStreak = 0;
 }
 
 VideoIOScheduleTime VideoPlayoutScheduler::NextScheduleTime()
@@ -29,10 +32,38 @@ VideoIOScheduleTime VideoPlayoutScheduler::NextScheduleTime()
 	return time;
 }
 
-void VideoPlayoutScheduler::AccountForCompletionResult(VideoIOCompletionResult result)
+VideoPlayoutRecoveryDecision VideoPlayoutScheduler::AccountForCompletionResult(VideoIOCompletionResult result, uint64_t readyQueueDepth)
 {
-	if (result == VideoIOCompletionResult::DisplayedLate || result == VideoIOCompletionResult::Dropped)
-		mScheduledFrameIndex += mPolicy.lateOrDropCatchUpFrames;
+	++mCompletedFrameIndex;
+	if (result == VideoIOCompletionResult::DisplayedLate)
+		++mLateStreak;
+	else
+		mLateStreak = 0;
+	if (result == VideoIOCompletionResult::Dropped)
+		++mDropStreak;
+	else
+		mDropStreak = 0;
+
+	const uint64_t measuredLagFrames = MeasureLag(result, readyQueueDepth);
+	const uint64_t catchUpFrames = measuredLagFrames < mPolicy.lateOrDropCatchUpFrames
+		? measuredLagFrames
+		: mPolicy.lateOrDropCatchUpFrames;
+	if (catchUpFrames > 0)
+		mScheduledFrameIndex += catchUpFrames;
+
+	VideoPlayoutRecoveryDecision decision;
+	decision.result = result;
+	decision.completedFrameIndex = mCompletedFrameIndex;
+	decision.scheduledFrameIndex = mScheduledFrameIndex;
+	decision.readyQueueDepth = readyQueueDepth;
+	decision.scheduledLeadFrames = mScheduledFrameIndex > mCompletedFrameIndex
+		? mScheduledFrameIndex - mCompletedFrameIndex
+		: 0;
+	decision.measuredLagFrames = measuredLagFrames;
+	decision.catchUpFrames = catchUpFrames;
+	decision.lateStreak = mLateStreak;
+	decision.dropStreak = mDropStreak;
+	return decision;
 }
 
 double VideoPlayoutScheduler::FrameBudgetMilliseconds() const
@@ -41,3 +72,26 @@ double VideoPlayoutScheduler::FrameBudgetMilliseconds() const
 		? (static_cast<double>(mFrameDuration) * 1000.0) / static_cast<double>(mTimeScale)
 		: 0.0;
 }
+
+uint64_t VideoPlayoutScheduler::MeasureLag(VideoIOCompletionResult result, uint64_t readyQueueDepth) const
+{
+	if (result != VideoIOCompletionResult::DisplayedLate && result != VideoIOCompletionResult::Dropped)
+		return 0;
+
+	uint64_t lagFrames = 1;
+	if (result == VideoIOCompletionResult::DisplayedLate && mLateStreak > lagFrames)
+		lagFrames = mLateStreak;
+	if (result == VideoIOCompletionResult::Dropped && mDropStreak * 2 > lagFrames)
+		lagFrames = mDropStreak * 2;
+
+	if (mCompletedFrameIndex >= mScheduledFrameIndex)
+	{
+		const uint64_t scheduleLagFrames = mCompletedFrameIndex - mScheduledFrameIndex + 1;
+		if (scheduleLagFrames > lagFrames)
+			lagFrames = scheduleLagFrames;
+	}
+	if (readyQueueDepth < mPolicy.targetReadyFrames && mPolicy.targetReadyFrames - readyQueueDepth > lagFrames)
+		lagFrames = mPolicy.targetReadyFrames - readyQueueDepth;
+
+	return lagFrames;
+}