MediaStream Recorder: implement pause() and resume()

content/renderer/media/video_track_recorder.cc

Index: content/renderer/media/video_track_recorder.cc
diff --git a/content/renderer/media/video_track_recorder.cc b/content/renderer/media/video_track_recorder.cc
index a2755bddeb224fcbc0e1dc7cfb3a7a1c340ef79a..a33d44dee935bc53e452c9e91b4a1bc2f958d8a2 100644
--- a/content/renderer/media/video_track_recorder.cc
+++ b/content/renderer/media/video_track_recorder.cc
@@ -80,6 +80,8 @@ class VideoTrackRecorder::VpxEncoder final
   void StartFrameEncode(const scoped_refptr<VideoFrame>& frame,
                         base::TimeTicks capture_timestamp);
 
+  void set_paused(bool paused) { paused_ = paused; }
+
  private:
   friend class base::RefCountedThreadSafe<VpxEncoder>;
   ~VpxEncoder();
@@ -96,6 +98,9 @@ class VideoTrackRecorder::VpxEncoder final
   base::TimeDelta CalculateFrameDuration(
       const scoped_refptr<VideoFrame>& frame);
 
+  // While |paused_|, frames are not encoded.
+  bool paused_;
+
   // Force usage of VP9 for encoding, instead of VP8 which is the default.
   const bool use_vp9_;
 
@@ -136,7 +141,8 @@ void VideoTrackRecorder::VpxEncoder::ShutdownEncoder(
 VideoTrackRecorder::VpxEncoder::VpxEncoder(
     bool use_vp9,
     const OnEncodedVideoCB& on_encoded_video_callback)
-    : use_vp9_(use_vp9),
+    : paused_(false),
+      use_vp9_(use_vp9),
       main_task_runner_(base::MessageLoop::current()->task_runner()),
       on_encoded_video_callback_(on_encoded_video_callback),
       encoding_thread_(new base::Thread("EncodingThread")) {
@@ -162,7 +168,8 @@ void VideoTrackRecorder::VpxEncoder::StartFrameEncode(
   if (!origin_task_runner_.get())
     origin_task_runner_ = base::MessageLoop::current()->task_runner();
   DCHECK(origin_task_runner_->BelongsToCurrentThread());
-
+  if (paused_)
+    return;

[emircan, 2015/10/20 22:00:27]

Move to l.167?

   encoding_thread_->task_runner()->PostTask(
       FROM_HERE, base::Bind(&VpxEncoder::EncodeOnEncodingThread,
                             this, frame, capture_timestamp));
@@ -358,6 +365,18 @@ VideoTrackRecorder::~VideoTrackRecorder() {
   track_.reset();
 }
 
+void VideoTrackRecorder::Pause() {
+  DCHECK(main_render_thread_checker_.CalledOnValidThread());
+  DCHECK(encoder_);
+  encoder_->set_paused(true);
+}
+
+void VideoTrackRecorder::Resume() {
+  DCHECK(main_render_thread_checker_.CalledOnValidThread());
+  DCHECK(encoder_);
+  encoder_->set_paused(false);
+}
+
 void VideoTrackRecorder::OnVideoFrameForTesting(
     const scoped_refptr<media::VideoFrame>& frame,
     base::TimeTicks timestamp) {