From 6ef854d2676b3c57d5e528483a8ca30f3bee5344 Mon Sep 17 00:00:00 2001
From: Matt Woodrow <mwoodrow@mozilla.com>
Date: Fri, 4 Dec 2015 13:33:21 +1300
Subject: [PATCH] Bug 1230338 - Record video frames dropped by the compositor,
 or while flushing during skip-to-keyframe. r=jya

---
 dom/media/MediaFormatReader.cpp   | 8 ++++++++
 dom/media/VideoFrameContainer.h   | 2 ++
 dom/media/mediasink/VideoSink.cpp | 5 +++++
 dom/media/mediasink/VideoSink.h   | 2 ++
 4 files changed, 17 insertions(+)

diff --git a/dom/media/MediaFormatReader.cpp b/dom/media/MediaFormatReader.cpp
index 6271c2d28674..82b8a334335e 100644
--- a/dom/media/MediaFormatReader.cpp
+++ b/dom/media/MediaFormatReader.cpp
@@ -510,6 +510,14 @@ MediaFormatReader::RequestVideoData(bool aSkipToNextKeyframe,
   if (ShouldSkip(aSkipToNextKeyframe, timeThreshold)) {
     // Cancel any pending demux request.
     mVideo.mDemuxRequest.DisconnectIfExists();
+
+    // I think it's still possible for an output to have been sent from the decoder
+    // and is currently sitting in our event queue waiting to be processed. The following
+    // flush won't clear it, and when we return to the event loop it'll be added to our
+    // output queue and be used.
+    // This code will count that as dropped, which was the intent, but not quite true.
+    mDecoder->NotifyDecodedFrames(0, 0, SizeOfVideoQueueInFrames());
+
     Flush(TrackInfo::kVideoTrack);
     RefPtr<VideoDataPromise> p = mVideo.mPromise.Ensure(__func__);
     SkipVideoDemuxToNextKeyFrame(timeThreshold);
diff --git a/dom/media/VideoFrameContainer.h b/dom/media/VideoFrameContainer.h
index 40bacec38e0f..7c07299b0315 100644
--- a/dom/media/VideoFrameContainer.h
+++ b/dom/media/VideoFrameContainer.h
@@ -78,6 +78,8 @@ public:
   B2G_ACL_EXPORT ImageContainer* GetImageContainer();
   void ForgetElement() { mElement = nullptr; }
 
+  uint32_t GetDroppedImageCount() { return mImageContainer->GetDroppedImageCount(); }
+
 protected:
   void SetCurrentFramesLocked(const gfx::IntSize& aIntrinsicSize,
                               const nsTArray<ImageContainer::NonOwningImage>& aImages);
diff --git a/dom/media/mediasink/VideoSink.cpp b/dom/media/mediasink/VideoSink.cpp
index 5f39decb875e..112686ee5cf9 100644
--- a/dom/media/mediasink/VideoSink.cpp
+++ b/dom/media/mediasink/VideoSink.cpp
@@ -35,6 +35,7 @@ VideoSink::VideoSink(AbstractThread* aThread,
   , mRealTime(aRealTime)
   , mFrameStats(aFrameStats)
   , mVideoFrameEndTime(-1)
+  , mOldDroppedCount(0)
   , mHasVideo(false)
   , mUpdateScheduler(aThread)
   , mVideoQueueSendToCompositorSize(aVQueueSentToCompositerSize)
@@ -327,6 +328,10 @@ VideoSink::RenderVideoFrames(int32_t aMaxFrames,
                 frame->mTime, frame->mFrameID, VideoQueue().GetSize());
   }
   mContainer->SetCurrentFrames(frames[0]->As<VideoData>()->mDisplay, images);
+
+  uint32_t dropped = mContainer->GetDroppedImageCount();
+  mFrameStats.NotifyDecodedFrames(0, 0, dropped - mOldDroppedCount);
+  mOldDroppedCount = dropped;
 }
 
 void
diff --git a/dom/media/mediasink/VideoSink.h b/dom/media/mediasink/VideoSink.h
index 0052c8da8627..c7c405d0c9b4 100644
--- a/dom/media/mediasink/VideoSink.h
+++ b/dom/media/mediasink/VideoSink.h
@@ -129,6 +129,8 @@ private:
   // in microseconds.
   int64_t mVideoFrameEndTime;
 
+  uint32_t mOldDroppedCount;
+
   // Event listeners for VideoQueue
   MediaEventListener mPushListener;