Support reading pixels from HW-decoded video textures into canvas/webgl.

content/renderer/media/renderer_gpu_video_decoder_factories.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.
 
 #ifndef CONTENT_RENDERER_MEDIA_RENDERER_GPU_VIDEO_DECODER_FACTORIES_H_
 #define CONTENT_RENDERER_MEDIA_RENDERER_GPU_VIDEO_DECODER_FACTORIES_H_
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
@@ skipping 31 matching lines @@
   virtual media::VideoDecodeAccelerator* CreateVideoDecodeAccelerator(
       media::VideoCodecProfile profile,
       media::VideoDecodeAccelerator::Client* client) OVERRIDE;
 
   virtual bool CreateTextures(int32 count, const gfx::Size& size,
                               std::vector<uint32>* texture_ids,
                               uint32 texture_target) OVERRIDE;
 
   virtual void DeleteTexture(uint32 texture_id) OVERRIDE;
 
+  virtual void ReadPixels(uint32 texture_id, uint32 texture_target,
+                          const gfx::Size& size, void* pixels) OVERRIDE;
+
   virtual base::SharedMemory* CreateSharedMemory(size_t size) OVERRIDE;
 
  protected:
   friend class base::RefCountedThreadSafe<RendererGpuVideoDecoderFactories>;
   virtual ~RendererGpuVideoDecoderFactories();
 
  private:
   // Helper for the constructor to acquire the ContentGLContext on the
   // compositor thread (when it is enabled).
   void AsyncGetContext(WebGraphicsContext3DCommandBufferImpl* context,
                        base::WaitableEvent* waiter);
 
   // Async versions of the public methods.  They use output parameters instead
   // of return values and each takes a WaitableEvent* param to signal completion
   // (except for DeleteTexture, which is fire-and-forget).
   // AsyncCreateSharedMemory runs on the renderer thread and the rest run on
   // |message_loop_|.
   void AsyncCreateVideoDecodeAccelerator(
       media::VideoCodecProfile profile,
       media::VideoDecodeAccelerator::Client* client,
       media::VideoDecodeAccelerator** vda,
       base::WaitableEvent* waiter);
   void AsyncCreateTextures(
       int32 count, const gfx::Size& size, std::vector<uint32>* texture_ids,
       uint32 texture_target, bool* success, base::WaitableEvent* waiter);
   void AsyncDeleteTexture(uint32 texture_id);
+  void AsyncReadPixels(uint32 texture_id, uint32 texture_target,
+                       const gfx::Size& size,
+                       void* pixels, base::WaitableEvent* waiter);
   void AsyncCreateSharedMemory(
       size_t size, base::SharedMemory** shm, base::WaitableEvent* waiter);
 
   scoped_refptr<base::MessageLoopProxy> message_loop_;
   scoped_refptr<GpuChannelHost> gpu_channel_host_;
   base::WeakPtr<WebGraphicsContext3DCommandBufferImpl> context_;
   DISALLOW_IMPLICIT_CONSTRUCTORS(RendererGpuVideoDecoderFactories);
 };
 
 #endif  // CONTENT_RENDERER_MEDIA_RENDERER_GPU_VIDEO_DECODER_FACTORIES_H_