telemetry and timing updates

apps/LoopThroughWithOpenGLCompositing/videoio/decklink/DeckLinkSession.cpp

@@ -532,17 +532,13 @@ bool DeckLinkSession::ScheduleFrame(IDeckLinkMutableVideoFrame* outputVideoFrame
 		return false;
 	}
 
-	BMDTimeValue streamTime = 0;
-	double playbackSpeed = 0.0;
-	if (output->GetScheduledStreamTime(mScheduler.TimeScale(), &streamTime, &playbackSpeed) == S_OK && playbackSpeed > 0.0)
+	if (mScheduleRealignmentPending)
 	{
-		RefreshBufferedVideoFrameCount();
-		const uint64_t leadFrames = mState.actualDeckLinkBufferedFramesAvailable
-			? static_cast<uint64_t>(mState.actualDeckLinkBufferedFrames) + 1
-			: static_cast<uint64_t>(mPlayoutPolicy.targetPrerollFrames);
-		mScheduler.AlignNextScheduleTimeToPlayback(streamTime, leadFrames);
+		RealignScheduleCursorToPlayback();
+		mScheduleRealignmentPending = false;
 	}
 
+	UpdateScheduleLeadTelemetry();
 	const VideoIOScheduleTime scheduleTime = mScheduler.NextScheduleTime();
 	const auto scheduleStart = std::chrono::steady_clock::now();
 	const HRESULT result = output->ScheduleVideoFrame(outputVideoFrame, scheduleTime.streamTime, scheduleTime.duration, scheduleTime.timeScale);
@@ -554,6 +550,49 @@ bool DeckLinkSession::ScheduleFrame(IDeckLinkMutableVideoFrame* outputVideoFrame
 	return result == S_OK;
 }
 
+void DeckLinkSession::UpdateScheduleLeadTelemetry()
+{
+	if (output == nullptr)
+	{
+		mState.deckLinkScheduleLeadAvailable = false;
+		return;
+	}
+
+	BMDTimeValue streamTime = 0;
+	double playbackSpeed = 0.0;
+	if (output->GetScheduledStreamTime(mScheduler.TimeScale(), &streamTime, &playbackSpeed) != S_OK || playbackSpeed <= 0.0)
+	{
+		mState.deckLinkScheduleLeadAvailable = false;
+		return;
+	}
+
+	const uint64_t playbackFrameIndex = streamTime >= 0 && mScheduler.FrameDuration() > 0
+		? static_cast<uint64_t>(streamTime / mScheduler.FrameDuration())
+		: 0;
+	const uint64_t nextScheduleFrameIndex = mScheduler.ScheduledFrameIndex();
+	mState.deckLinkScheduleLeadAvailable = true;
+	mState.deckLinkPlaybackStreamTime = streamTime;
+	mState.deckLinkPlaybackFrameIndex = playbackFrameIndex;
+	mState.deckLinkNextScheduleFrameIndex = nextScheduleFrameIndex;
+	mState.deckLinkScheduleLeadFrames = static_cast<int64_t>(nextScheduleFrameIndex) - static_cast<int64_t>(playbackFrameIndex);
+}
+
+void DeckLinkSession::RealignScheduleCursorToPlayback()
+{
+	if (output == nullptr)
+		return;
+
+	BMDTimeValue streamTime = 0;
+	double playbackSpeed = 0.0;
+	if (output->GetScheduledStreamTime(mScheduler.TimeScale(), &streamTime, &playbackSpeed) != S_OK || playbackSpeed <= 0.0)
+		return;
+
+	const VideoPlayoutPolicy policy = NormalizeVideoPlayoutPolicy(mPlayoutPolicy);
+	mScheduler.AlignNextScheduleTimeToPlayback(streamTime, policy.targetPrerollFrames);
+	++mState.deckLinkScheduleRealignmentCount;
+	UpdateScheduleLeadTelemetry();
+}
+
 bool DeckLinkSession::ScheduleSystemMemoryFrame(const VideoIOOutputFrame& frame)
 {
 	if (output == nullptr || frame.bytes == nullptr || frame.rowBytes <= 0 || frame.height == 0)
@@ -838,6 +877,18 @@ void DeckLinkSession::HandlePlayoutFrameCompleted(IDeckLinkVideoFrame* completed
 
 	VideoIOCompletion completion;
 	completion.result = TranslateCompletionResult(completionResult);
+	if (completion.result == VideoIOCompletionResult::DisplayedLate || completion.result == VideoIOCompletionResult::Dropped)
+	{
+		if (mScheduleRealignmentArmed)
+		{
+			mScheduleRealignmentPending = true;
+			mScheduleRealignmentArmed = false;
+		}
+	}
+	else if (completion.result == VideoIOCompletionResult::Completed)
+	{
+		mScheduleRealignmentArmed = true;
+	}
 	completion.outputFrameBuffer = completedSystemBuffer;
 	mOutputFrameCallback(completion);
 }

apps/LoopThroughWithOpenGLCompositing/videoio/decklink/DeckLinkSession.h

@@ -75,6 +75,8 @@ private:
 	bool AcquireNextOutputVideoFrame(CComPtr<IDeckLinkMutableVideoFrame>& outputVideoFrame);
 	bool PopulateOutputFrame(IDeckLinkMutableVideoFrame* outputVideoFrame, VideoIOOutputFrame& frame);
 	bool ScheduleFrame(IDeckLinkMutableVideoFrame* outputVideoFrame);
+	void UpdateScheduleLeadTelemetry();
+	void RealignScheduleCursorToPlayback();
 	bool ScheduleSystemMemoryFrame(const VideoIOOutputFrame& frame);
 	bool ScheduleBlackFrame(IDeckLinkMutableVideoFrame* outputVideoFrame);
 	void RefreshBufferedVideoFrameCount();
@@ -91,6 +93,8 @@ private:
 	VideoIOState							mState;
 	VideoPlayoutPolicy						mPlayoutPolicy;
 	VideoPlayoutScheduler					mScheduler;
+	bool									mScheduleRealignmentPending = false;
+	bool									mScheduleRealignmentArmed = true;
 	InputFrameCallback						mInputFrameCallback;
 	OutputFrameCallback						mOutputFrameCallback;
 };