Implemented way to share video frames between WebKit and Chromium

webkit/glue/media/web_video_renderer.h

 // Copyright (c) 2010 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 WEBKIT_GLUE_MEDIA_WEB_VIDEO_RENDERER_H_
 #define WEBKIT_GLUE_MEDIA_WEB_VIDEO_RENDERER_H_
 
+#include "media/base/video_frame.h"
 #include "media/filters/video_renderer_base.h"
 
 namespace webkit_glue {
 
 // A specialized version of a VideoRenderer designed to be used inside WebKit.
 class WebVideoRenderer : public media::VideoRendererBase {
  public:
   WebVideoRenderer() : media::VideoRendererBase() {}
   virtual ~WebVideoRenderer() {}
 
   // This method is called with the same rect as the Paint() method and could
   // be used by future implementations to implement an improved color space +
   // scale code on a separate thread.  Since we always do the stretch on the
   // same thread as the Paint method, we just ignore the call for now.
   //
   // Method called on the render thread.
   virtual void SetRect(const gfx::Rect& rect) = 0;
 
   // Paint the current front frame on the |canvas| stretching it to fit the
   // |dest_rect|.
   //
   // Method called on the render thread.
   virtual void Paint(skia::PlatformCanvas* canvas,
                      const gfx::Rect& dest_rect) = 0;
 
+  // Clients of this class (painter/compositor) should use GetCurrentFrame()
+  // obtain ownership of VideoFrame, it should always relinquish the ownership
+  // by use PutCurrentFrame(). Current frame is not guaranteed to be non-NULL.
+  // It expects clients to use color-fill the background if current frame
+  // is NULL. This could happen when before pipeline is pre-rolled or during
+  // pause/flush/seek.
+  virtual void GetCurrentFrame(scoped_refptr<media::VideoFrame>* frame_out) {}
+  virtual void PutCurrentFrame(scoped_refptr<media::VideoFrame> frame) {}
+
  private:
   DISALLOW_COPY_AND_ASSIGN(WebVideoRenderer);
 };
 
 }  // namespace webkit_glue
 
 #endif  // WEBKIT_GLUE_MEDIA_WEB_VIDEO_RENDERER_H_