Revert 266822 "Remove dropped frame counting and task posting fr..."

trunk/src/content/renderer/media/video_frame_compositor.cc

 // 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.
 
 #include "content/renderer/media/video_frame_compositor.h"
 
+#include "base/bind.h"
+#include "base/location.h"
+#include "base/single_thread_task_runner.h"
+#include "cc/layers/video_frame_provider.h"
+#include "content/renderer/render_thread_impl.h"
 #include "media/base/video_frame.h"
 
 namespace content {
 
 static bool IsOpaque(const scoped_refptr<media::VideoFrame>& frame) {
   switch (frame->format()) {
     case media::VideoFrame::UNKNOWN:
     case media::VideoFrame::YV12:
     case media::VideoFrame::YV12J:
     case media::VideoFrame::YV16:
     case media::VideoFrame::I420:
       return true;
 
     case media::VideoFrame::YV12A:
 #if defined(VIDEO_HOLE)
     case media::VideoFrame::HOLE:
 #endif  // defined(VIDEO_HOLE)
     case media::VideoFrame::NATIVE_TEXTURE:
       break;
   }
   return false;
 }
 
+class VideoFrameCompositor::Internal : public cc::VideoFrameProvider {
+ public:
+  Internal(
+      const scoped_refptr<base::SingleThreadTaskRunner>& compositor_task_runner,
+      const base::Callback<void(gfx::Size)>& natural_size_changed_cb,
+      const base::Callback<void(bool)>& opacity_changed_cb)
+      : compositor_task_runner_(compositor_task_runner),
+        natural_size_changed_cb_(natural_size_changed_cb),
+        opacity_changed_cb_(opacity_changed_cb),
+        client_(NULL),
+        compositor_notification_pending_(false),
+        frames_dropped_before_compositor_was_notified_(0) {}
+
+  virtual ~Internal() {
+    if (client_)
+      client_->StopUsingProvider();
+  }
+
+  void DeleteSoon() {
+    compositor_task_runner_->DeleteSoon(FROM_HERE, this);
+  }
+
+  void UpdateCurrentFrame(const scoped_refptr<media::VideoFrame>& frame) {
+    base::AutoLock auto_lock(lock_);
+
+    if (current_frame_ &&
+        current_frame_->natural_size() != frame->natural_size()) {
+      natural_size_changed_cb_.Run(frame->natural_size());
+    }
+
+    if (!current_frame_ || IsOpaque(current_frame_) != IsOpaque(frame)) {
+      opacity_changed_cb_.Run(IsOpaque(frame));
+    }
+
+    current_frame_ = frame;
+
+    // Count frames as dropped if and only if we updated the frame but didn't
+    // finish notifying the compositor for the previous frame.
+    if (compositor_notification_pending_) {
+      if (frames_dropped_before_compositor_was_notified_ < kuint32max)
+        ++frames_dropped_before_compositor_was_notified_;
+      return;
+    }
+
+    compositor_notification_pending_ = true;
+    compositor_task_runner_->PostTask(
+        FROM_HERE,
+        base::Bind(&Internal::NotifyCompositorOfNewFrame,
+                   base::Unretained(this)));
+  }
+
+  uint32 GetFramesDroppedBeforeCompositorWasNotified() {
+    base::AutoLock auto_lock(lock_);
+    return frames_dropped_before_compositor_was_notified_;
+  }
+
+  void SetFramesDroppedBeforeCompositorWasNotifiedForTesting(
+      uint32 dropped_frames) {
+    base::AutoLock auto_lock(lock_);
+    frames_dropped_before_compositor_was_notified_ = dropped_frames;
+  }
+
+  // cc::VideoFrameProvider implementation.
+  virtual void SetVideoFrameProviderClient(
+      cc::VideoFrameProvider::Client* client) OVERRIDE {
+    if (client_)
+      client_->StopUsingProvider();
+    client_ = client;
+  }
+
+  virtual scoped_refptr<media::VideoFrame> GetCurrentFrame() OVERRIDE {
+    base::AutoLock auto_lock(lock_);
+    return current_frame_;
+  }
+
+  virtual void PutCurrentFrame(const scoped_refptr<media::VideoFrame>& frame)
+      OVERRIDE {}
+
+ private:
+  void NotifyCompositorOfNewFrame() {
+    base::AutoLock auto_lock(lock_);
+    compositor_notification_pending_ = false;
+    if (client_)
+      client_->DidReceiveFrame();
+  }
+
+  scoped_refptr<base::SingleThreadTaskRunner> compositor_task_runner_;
+  base::Callback<void(gfx::Size)> natural_size_changed_cb_;
+  base::Callback<void(bool)> opacity_changed_cb_;
+
+  cc::VideoFrameProvider::Client* client_;
+
+  base::Lock lock_;
+  scoped_refptr<media::VideoFrame> current_frame_;
+  bool compositor_notification_pending_;
+  uint32 frames_dropped_before_compositor_was_notified_;
+
+  DISALLOW_COPY_AND_ASSIGN(Internal);
+};
+
 VideoFrameCompositor::VideoFrameCompositor(
+    const scoped_refptr<base::SingleThreadTaskRunner>& compositor_task_runner,
     const base::Callback<void(gfx::Size)>& natural_size_changed_cb,
     const base::Callback<void(bool)>& opacity_changed_cb)
-    : natural_size_changed_cb_(natural_size_changed_cb),
-      opacity_changed_cb_(opacity_changed_cb),
-      client_(NULL) {
+    : internal_(new Internal(compositor_task_runner,
+                             natural_size_changed_cb,
+                             opacity_changed_cb)) {
 }
 
 VideoFrameCompositor::~VideoFrameCompositor() {
-  if (client_)
-    client_->StopUsingProvider();
+  internal_->DeleteSoon();
 }
 
-void VideoFrameCompositor::SetVideoFrameProviderClient(
-    cc::VideoFrameProvider::Client* client) {
-  if (client_)
-    client_->StopUsingProvider();
-  client_ = client;
-}
-
-scoped_refptr<media::VideoFrame> VideoFrameCompositor::GetCurrentFrame() {
-  base::AutoLock auto_lock(lock_);
-  return current_frame_;
-}
-
-void VideoFrameCompositor::PutCurrentFrame(
-    const scoped_refptr<media::VideoFrame>& frame) {
+cc::VideoFrameProvider* VideoFrameCompositor::GetVideoFrameProvider() {
+  return internal_;
 }
 
 void VideoFrameCompositor::UpdateCurrentFrame(
     const scoped_refptr<media::VideoFrame>& frame) {
-  base::AutoLock auto_lock(lock_);
+  internal_->UpdateCurrentFrame(frame);
+}
 
-  if (current_frame_ &&
-      current_frame_->natural_size() != frame->natural_size()) {
-    natural_size_changed_cb_.Run(frame->natural_size());
-  }
+scoped_refptr<media::VideoFrame> VideoFrameCompositor::GetCurrentFrame() {
+  return internal_->GetCurrentFrame();
+}
 
-  if (!current_frame_ || IsOpaque(current_frame_) != IsOpaque(frame)) {
-    opacity_changed_cb_.Run(IsOpaque(frame));
-  }
+uint32 VideoFrameCompositor::GetFramesDroppedBeforeCompositorWasNotified() {
+  return internal_->GetFramesDroppedBeforeCompositorWasNotified();
+}
 
-  current_frame_ = frame;
-
-  if (client_)
-    client_->DidReceiveFrame();
+void
+VideoFrameCompositor::SetFramesDroppedBeforeCompositorWasNotifiedForTesting(
+    uint32 dropped_frames) {
+  internal_->SetFramesDroppedBeforeCompositorWasNotifiedForTesting(
+      dropped_frames);
 }
 
 }  // namespace content