Support multiple video decoders and encoders

content/common/gpu/media/gpu_video_decode_accelerator.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_COMMON_GPU_MEDIA_GPU_VIDEO_DECODE_ACCELERATOR_H_
 #define CONTENT_COMMON_GPU_MEDIA_GPU_VIDEO_DECODE_ACCELERATOR_H_
 
 #include <map>
 #include <vector>
 
@@ skipping 13 matching lines @@
 }
 
 namespace content {
 
 class GpuVideoDecodeAccelerator
     : public IPC::Listener,
       public IPC::Sender,
       public media::VideoDecodeAccelerator::Client,
       public GpuCommandBufferStub::DestructionObserver {
  public:
+  typedef base::Callback<scoped_ptr<media::VideoDecodeAccelerator>(void)>

[Pawel Osciak, 2014/12/31 07:55:59]

This could be private?

[henryhsu, 2014/12/31 08:47:53]

Done.

+      CreateVDACb;
+
   // Each of the arguments to the constructor must outlive this object.
   // |stub->decoder()| will be made current around any operation that touches
   // the underlying VDA so that it can make GL calls safely.
   GpuVideoDecodeAccelerator(
       int32 host_route_id,
       GpuCommandBufferStub* stub,
       const scoped_refptr<base::MessageLoopProxy>& io_message_loop);
 
   // IPC::Listener implementation.
   bool OnMessageReceived(const IPC::Message& message) override;
 
   // media::VideoDecodeAccelerator::Client implementation.
   void ProvidePictureBuffers(uint32 requested_num_of_buffers,
                              const gfx::Size& dimensions,
                              uint32 texture_target) override;
   void DismissPictureBuffer(int32 picture_buffer_id) override;
   void PictureReady(const media::Picture& picture) override;
   void NotifyError(media::VideoDecodeAccelerator::Error error) override;
   void NotifyEndOfBitstreamBuffer(int32 bitstream_buffer_id) override;
   void NotifyFlushDone() override;
   void NotifyResetDone() override;
 
   // GpuCommandBufferStub::DestructionObserver implementation.
   void OnWillDestroyStub() override;
 
   // Function to delegate sending to actual sender.
   bool Send(IPC::Message* message) override;
 
-  // Initialize the accelerator with the given profile and send the
-  // |init_done_msg| when done.
+  // Prepare all appropriate platform-specific VDAs and initialize VDAs with

[Pawel Osciak, 2014/12/31 07:55:59]

The final effect is only one initialized VDA, perhaps:

"Initialize VDAs from the set of VDAs supported for current platform until one
of them succeeds for given |profile|."

[henryhsu, 2014/12/31 08:47:53]

Done.

+  // |profile|. Send the |init_done_msg| when done. filter_ is passed to
+  // GpuCommandBufferStube channel only if we can decode on IO thread.
   void Initialize(const media::VideoCodecProfile profile,
                   IPC::Message* init_done_msg);
 
  private:
   class MessageFilter;
 
+  // Create the appropriate platform-specific VDA callback functions.

[Pawel Osciak, 2014/12/31 07:55:59]

Return a set of VDA Create callback functions applicable to the current
platform.

[henryhsu, 2014/12/31 08:47:53]

Done.

+  std::vector<CreateVDACb> CreateDecoderCbs();
+  // Create DXVA VDA.

[Pawel Osciak, 2014/12/31 07:55:59]

These comments are probably unnecessary, method names are self-explanatory.

[henryhsu, 2014/12/31 08:47:53]

Done.

+  scoped_ptr<media::VideoDecodeAccelerator> CreateDXVADecoder();

[Pawel Osciak, 2014/12/31 07:55:59]

Could we please s/Decoder/VDA/ everywhere?

[henryhsu, 2014/12/31 08:47:53]

Done.

+  // Create V4L2 VDA.
+  scoped_ptr<media::VideoDecodeAccelerator> CreateV4L2Decoder();
+  // Create Vaapi VDA.
+  scoped_ptr<media::VideoDecodeAccelerator> CreateVaapiDecoder();
+  // Create VT VDA.
+  scoped_ptr<media::VideoDecodeAccelerator> CreateVTDecoder();
+  // Create Android VDA.
+  scoped_ptr<media::VideoDecodeAccelerator> CreateAndroidDecoder();
+  // Create Ozone VDA.
+  scoped_ptr<media::VideoDecodeAccelerator> CreateOzoneDecoder();
+
   // We only allow self-delete, from OnWillDestroyStub(), after cleanup there.
   ~GpuVideoDecodeAccelerator() override;
 
   // Handlers for IPC messages.
   void OnDecode(base::SharedMemoryHandle handle, int32 id, uint32 size);
   void OnAssignPictureBuffers(const std::vector<int32>& buffer_ids,
                               const std::vector<uint32>& texture_ids);
   void OnReusePictureBuffer(int32 picture_buffer_id);
   void OnFlush();
   void OnReset();
@@ skipping 52 matching lines @@
 
   // A map from picture buffer ID to TextureRef that have not been cleared.
   std::map<int32, scoped_refptr<gpu::gles2::TextureRef> > uncleared_textures_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(GpuVideoDecodeAccelerator);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_MEDIA_GPU_VIDEO_DECODE_ACCELERATOR_H_