Add MediaStreamSource frame rate calculation to the tracker.

content/renderer/media/video_track_adapter.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_RENDERER_MEDIA_VIDEO_TRACK_ADAPTER_H_
 #define CONTENT_RENDERER_MEDIA_VIDEO_TRACK_ADAPTER_H_
 
 #include <vector>
+#include <queue>
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/time/time.h"
 #include "content/renderer/media/media_stream_video_track.h"
 #include "media/base/video_frame.h"
 
 namespace content {
 
 // VideoTrackAdapter is a helper class used by MediaStreamVideoSource used for
 // adapting the video resolution from a source implementation to the resolution
 // a track requires. Different tracks can have different resolution constraints.
 // The constraints can be set as max width and height as well as max and min
 // aspect ratio.
 // Video frames are delivered to a track using a VideoCaptureDeliverFrameCB on
 // the IO-thread.
 // Adaptations is done by wrapping the original media::VideoFrame in a new
 // media::VideoFrame with a new visible_rect and natural_size.
 class VideoTrackAdapter
     : public base::RefCountedThreadSafe<VideoTrackAdapter> {
  public:
-  typedef base::Callback<void(bool mute_state)> OnMutedCallback;
+  typedef base::Callback<void(float framerate, int dropped_frames)> OnFrameRateCallback;
 
   explicit VideoTrackAdapter(
       const scoped_refptr<base::MessageLoopProxy>& io_message_loop);
 
   // Register |track| to receive video frames in |frame_callback| with
   // a resolution within the boundaries of the arguments.
   // Must be called on the main render thread. |frame_callback| is guaranteed to
   // be released on the main render thread.
   // |source_frame_rate| is used to calculate a prudent interval to check for
   // passing frames and inform of the result via |on_muted_state_callback|.
@@ skipping 14 matching lines @@
 
   const scoped_refptr<base::MessageLoopProxy>& io_message_loop() {
     DCHECK(thread_checker_.CalledOnValidThread());
     return io_message_loop_;
   }
 
   // Start monitor that frames are delivered to this object. I.E, that
   // |DeliverFrameOnIO| is called with a frame rate of |source_frame_rate|.
   // |on_muted_callback| is triggered on the main render thread.
   void StartFrameMonitoring(double source_frame_rate,
-                            const OnMutedCallback& on_muted_callback);
+                            const OnFrameRateCallback& on_muted_callback);
   void StopFrameMonitoring();
 
  private:
   virtual ~VideoTrackAdapter();
   friend class base::RefCountedThreadSafe<VideoTrackAdapter>;
 
+  typedef base::Callback<void(float framerate, int dropped_frames)>
+      FrameRateCallback;
+
   void AddTrackOnIO(
       const MediaStreamVideoTrack* track,
       VideoCaptureDeliverFrameCB frame_callback,
       const gfx::Size& max_frame_size,
       double min_aspect_ratio,
       double max_aspect_ratio,
       double max_frame_rate);
   void RemoveTrackOnIO(const MediaStreamVideoTrack* track);
 
   void StartFrameMonitoringOnIO(
-    const OnMutedCallback& on_muted_state_callback,
+    const OnFrameRateCallback& on_muted_state_callback,
     double source_frame_rate);
   void StopFrameMonitoringOnIO();
 
   // Compare |frame_counter_snapshot| with the current |frame_counter_|, and
   // inform of the situation (muted, not muted) via |set_muted_state_callback|.
-  void CheckFramesReceivedOnIO(const OnMutedCallback& set_muted_state_callback,
-                               uint64 old_frame_counter_snapshot);
+  void CheckFramesReceivedOnIO(const OnFrameRateCallback& set_muted_state_callback,
+                               uint64 old_frame_counter_snapshot,
+                               int old_dropped_frame_counter_snapshot);
+
+  void UpdateFrameRateOnIO(base::TimeDelta timestamp);
+  float GetFrameRateOnIO();
 
   // |thread_checker_| is bound to the main render thread.
   base::ThreadChecker thread_checker_;
 
   scoped_refptr<base::MessageLoopProxy> io_message_loop_;
 
   // |renderer_task_runner_| is used to ensure that
   // VideoCaptureDeliverFrameCB is released on the main render thread.
   scoped_refptr<base::SingleThreadTaskRunner> renderer_task_runner_;
 
@@ skipping 12 matching lines @@
   // Keeps track of it frames have been received. It is only accessed on the
   // IO-thread.
   bool muted_state_;
 
   // Running frame counter, accessed on the IO-thread.
   uint64 frame_counter_;
 
   // Frame rate configured on the video source, accessed on the IO-thread.
   float source_frame_rate_;
 
+  int dropped_frames_counter_;
+  std::queue<base::TimeDelta> frame_timestamps_;
+
   DISALLOW_COPY_AND_ASSIGN(VideoTrackAdapter);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_VIDEO_TRACK_ADAPTER_H_