Tab Capture: Backing store readbacks to YV12 VideoFrames.

content/browser/renderer_host/media/video_capture_controller.h

 // Copyright (c) 2012 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.
 
 // VideoCaptureController is the glue between VideoCaptureHost,
 // VideoCaptureManager and VideoCaptureDevice.
 // It provides functions for VideoCaptureHost to start a VideoCaptureDevice and
 // is responsible for keeping track of shared DIBs and filling them with I420
 // video frames for IPC communication between VideoCaptureHost and
 // VideoCaptureMessageFilter.
@@ skipping 50 matching lines @@
   // Return a buffer previously given in
   // VideoCaptureControllerEventHandler::OnBufferReady.
   void ReturnBuffer(const VideoCaptureControllerID& id,
                     VideoCaptureControllerEventHandler* event_handler,
                     int buffer_id);
 
   // Implement media::VideoCaptureDevice::EventHandler.
   virtual void OnIncomingCapturedFrame(const uint8* data,
                                        int length,
                                        base::Time timestamp) OVERRIDE;
+  virtual void OnIncomingCapturedVideoFrame(media::VideoFrame* frame,
+                                            base::Time timestamp) OVERRIDE;
   virtual void OnError() OVERRIDE;
   virtual void OnFrameInfo(
       const media::VideoCaptureCapability& info) OVERRIDE;
 
  protected:
   virtual ~VideoCaptureController();
 
  private:
   friend class base::RefCountedThreadSafe<VideoCaptureController>;
 
   struct ControllerClient;
   typedef std::list<ControllerClient*> ControllerClients;
 
   // Callback when manager has stopped device.
   void OnDeviceStopped();
 
   // Worker functions on IO thread.
   void DoIncomingCapturedFrameOnIOThread(int buffer_id, base::Time timestamp);
   void DoFrameInfoOnIOThread();
   void DoErrorOnIOThread();
   void DoDeviceStoppedOnIOThread();
 
   // Send frame info and init buffers to |client|.
   void SendFrameInfoAndBuffers(ControllerClient* client, int buffer_size);
 
-  // Helpers.
   // Find a client of |id| and |handler| in |clients|.
   ControllerClient* FindClient(
       const VideoCaptureControllerID& id,
       VideoCaptureControllerEventHandler* handler,
       const ControllerClients& clients);
+
   // Find a client of |session_id| in |clients|.
   ControllerClient* FindClient(
       int session_id,
       const ControllerClients& clients);
+
   // Decide what to do after kStopping state. Dependent on events, controller
   // can stay in kStopping state, or go to kStopped, or restart capture.
   void PostStopping();
+
   // Check if any DIB is used by client.
   bool ClientHasDIB();
 
+  // DIB reservation. Locate an available DIB object, reserve it, and provide
+  // the caller the reserved DIB's buffer_id as well as pointers to its color
+  // planes. Returns true if successful.
+  bool ReserveSharedMemory(int* buffer_id_out,
+                           uint8** yplane,
+                           uint8** uplane,
+                           uint8** vplane);
+
   // Lock to protect free_dibs_ and owned_dibs_.
   base::Lock lock_;
 
   struct SharedDIB;
   typedef std::map<int /*buffer_id*/, SharedDIB*> DIBMap;
   // All DIBs created by this object.
   // It's modified only on IO thread.
   DIBMap owned_dibs_;
 
   // All clients served by this controller.
@@ skipping 20 matching lines @@
 
   bool device_in_use_;
   VideoCaptureState state_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(VideoCaptureController);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_VIDEO_CAPTURE_CONTROLLER_H_