Fix frames dropped statistics

The |frames_dropped| statistics contain not only frames that are dropped
but also frames that are in internal queues. This CL changes that so
that |frames_dropped| only contains frames that are dropped.

Bug: chromium:990317
Change-Id: If222568501b277a75bc514661c4f8f861b56aaed
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/150111
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Reviewed-by: Niels Moller <nisse@webrtc.org>
Commit-Queue: Johannes Kron <kron@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#28968}

modules/video_coding/frame_buffer2.cc

@@ -286,6 +286,17 @@ EncodedFrame* FrameBuffer::GetNextFrame() {
     decoded_frames_history_.InsertDecoded(frame_it->first, frame->Timestamp());
 
     // Remove decoded frame and all undecoded frames before it.
+    if (stats_callback_) {
+      unsigned int dropped_frames = std::count_if(
+          frames_.begin(), frame_it,
+          [](const std::pair<const VideoLayerFrameId, FrameInfo>& frame) {
+            return frame.second.frame != nullptr;
+          });
+      if (dropped_frames > 0) {
+        stats_callback_->OnDroppedFrames(dropped_frames);
+      }
+    }
+
     frames_.erase(frames_.begin(), ++frame_it);
 
     frames_out.push_back(frame);
@@ -723,6 +734,16 @@ void FrameBuffer::UpdateTimingFrameInfo() {
 
 void FrameBuffer::ClearFramesAndHistory() {
   TRACE_EVENT0("webrtc", "FrameBuffer::ClearFramesAndHistory");
+  if (stats_callback_) {
+    unsigned int dropped_frames = std::count_if(
+        frames_.begin(), frames_.end(),
+        [](const std::pair<const VideoLayerFrameId, FrameInfo>& frame) {
+          return frame.second.frame != nullptr;
+        });
+    if (dropped_frames > 0) {
+      stats_callback_->OnDroppedFrames(dropped_frames);
+    }
+  }
   frames_.clear();
   last_continuous_frame_.reset();
   frames_to_decode_.clear();

modules/video_coding/frame_buffer2_unittest.cc

@@ -111,6 +111,7 @@ class VCMReceiveStatisticsCallbackMock : public VCMReceiveStatisticsCallback {
                void(bool is_keyframe,
                     size_t size_bytes,
                     VideoContentType content_type));
+  MOCK_METHOD1(OnDroppedFrames, void(uint32_t frames_dropped));
   MOCK_METHOD1(OnDiscardedPacketsUpdated, void(int discarded_packets));
   MOCK_METHOD1(OnFrameCountsUpdated, void(const FrameCounts& frame_counts));
   MOCK_METHOD6(OnFrameBufferTimingsUpdated,
@@ -406,6 +407,8 @@ TEST_F(TestFrameBuffer2, DropTemporalLayerSlowDecoder) {
                 pid + i, pid + i - 1);
   }
 
+  EXPECT_CALL(stats_callback_, OnDroppedFrames(1)).Times(3);
+
   for (int i = 0; i < 10; ++i) {
     ExtractFrame();
     clock_.AdvanceTimeMilliseconds(70);
@@ -423,6 +426,41 @@ TEST_F(TestFrameBuffer2, DropTemporalLayerSlowDecoder) {
   CheckNoFrame(9);
 }
 
+TEST_F(TestFrameBuffer2, DropFramesIfSystemIsStalled) {
+  uint16_t pid = Rand();
+  uint32_t ts = Rand();
+
+  InsertFrame(pid, 0, ts, false, true, kFrameSize);
+  InsertFrame(pid + 1, 0, ts + 1 * kFps10, false, true, kFrameSize, pid);
+  InsertFrame(pid + 2, 0, ts + 2 * kFps10, false, true, kFrameSize, pid + 1);
+  InsertFrame(pid + 3, 0, ts + 3 * kFps10, false, true, kFrameSize);
+
+  ExtractFrame();
+  // Jump forward in time, simulating the system being stalled for some reason.
+  clock_.AdvanceTimeMilliseconds(3 * kFps10);
+  // Extract one more frame, expect second and third frame to be dropped.
+  EXPECT_CALL(stats_callback_, OnDroppedFrames(2)).Times(1);
+  ExtractFrame();
+
+  CheckFrame(0, pid + 0, 0);
+  CheckFrame(1, pid + 3, 0);
+}
+
+TEST_F(TestFrameBuffer2, DroppedFramesCountedOnClear) {
+  uint16_t pid = Rand();
+  uint32_t ts = Rand();
+
+  InsertFrame(pid, 0, ts, false, true, kFrameSize);
+  for (int i = 1; i < 5; ++i) {
+    InsertFrame(pid + i, 0, ts + i * kFps10, false, true, kFrameSize,
+                pid + i - 1);
+  }
+
+  // All frames should be dropped when Clear is called.
+  EXPECT_CALL(stats_callback_, OnDroppedFrames(5)).Times(1);
+  buffer_->Clear();
+}
+
 TEST_F(TestFrameBuffer2, InsertLateFrame) {
   uint16_t pid = Rand();
   uint32_t ts = Rand();

modules/video_coding/generic_decoder.cc

@@ -78,6 +78,7 @@ void VCMDecodedFrameCallback::Decoded(VideoFrame& decodedImage,
   if (frameInfo == NULL) {
     RTC_LOG(LS_WARNING) << "Too many frames backed up in the decoder, dropping "
                            "this one.";
+    _receiveCallback->OnDroppedFrames(1);
     return;
   }
 
@@ -163,6 +164,7 @@ int32_t VCMDecodedFrameCallback::Pop(uint32_t timestamp) {
   if (_timestampMap.Pop(timestamp) == NULL) {
     return VCM_GENERAL_ERROR;
   }
+  _receiveCallback->OnDroppedFrames(1);
   return VCM_OK;
 }
 

modules/video_coding/include/video_coding_defines.h

@@ -67,6 +67,8 @@ class VCMReceiveCallback {
     return FrameToRender(videoFrame, qp, content_type);
   }
 
+  virtual void OnDroppedFrames(uint32_t frames_dropped);
+
   // Called when the current receive codec changes.
   virtual void OnIncomingPayloadType(int payload_type);
   virtual void OnDecoderImplementationName(const char* implementation_name);
@@ -83,6 +85,8 @@ class VCMReceiveStatisticsCallback {
                                size_t size_bytes,
                                VideoContentType content_type) = 0;
 
+  virtual void OnDroppedFrames(uint32_t frames_dropped) = 0;
+
   virtual void OnFrameBufferTimingsUpdated(int max_decode_ms,
                                            int current_delay_ms,
                                            int target_delay_ms,

modules/video_coding/video_coding_defines.cc

@@ -12,6 +12,7 @@
 
 namespace webrtc {
 
+void VCMReceiveCallback::OnDroppedFrames(uint32_t frames_dropped) {}
 void VCMReceiveCallback::OnIncomingPayloadType(int payload_type) {}
 void VCMReceiveCallback::OnDecoderImplementationName(
     const char* implementation_name) {}