media: Enabling direct rendering for VP9

media/filters/vpx_video_decoder.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 MEDIA_FILTERS_VPX_VIDEO_DECODER_H_
 #define MEDIA_FILTERS_VPX_VIDEO_DECODER_H_
 
 #include "base/callback.h"
 #include "base/memory/weak_ptr.h"
 #include "media/base/demuxer_stream.h"
 #include "media/base/video_decoder.h"
 #include "media/base/video_decoder_config.h"
 #include "media/base/video_frame.h"
 #include "media/base/video_frame_pool.h"
 
 struct vpx_codec_ctx;
+struct vpx_codec_frame_buffer;
 struct vpx_image;
 
 namespace base {
 class MessageLoopProxy;
 }
 
 namespace media {
 
 // Libvpx video decoder wrapper.
 // Note: VpxVideoDecoder accepts only YV12A VP8 content or VP9 content. This is
 // done to avoid usurping FFmpeg for all vp8 decoding, because the FFmpeg VP8
 // decoder is faster than the libvpx VP8 decoder.
 class MEDIA_EXPORT VpxVideoDecoder : public VideoDecoder {
  public:
   explicit VpxVideoDecoder(
       const scoped_refptr<base::MessageLoopProxy>& message_loop);
   virtual ~VpxVideoDecoder();
 
   // VideoDecoder implementation.
   virtual void Initialize(const VideoDecoderConfig& config,
                           const PipelineStatusCB& status_cb) OVERRIDE;
   virtual void Decode(const scoped_refptr<DecoderBuffer>& buffer,
                       const DecodeCB& decode_cb) OVERRIDE;
   virtual void Reset(const base::Closure& closure) OVERRIDE;
   virtual void Stop(const base::Closure& closure) OVERRIDE;
   virtual bool HasAlpha() const OVERRIDE;
 
+  // Callback that will be called by libvpx if the frame buffer size needs to
+  // increase. Parameters:
+  // user_priv  Data passed into libvpx (we pass NULL).
+  // new_size   Minimum size needed by libvpx to decompress the next frame.
+  // fb         Pointer to the frame buffer to update.
+  // Returns VPX_CODEC_OK on success. Returns < 0 on failure.
+  static int32 ReallocVP9FrameBuffer(void* user_priv, size_t new_size,

[fgalligan1, 2013/12/17 01:16:54]

nit: I think we use int other places.

[vignesh, 2013/12/17 18:24:25]

i tried int first. clang was not happy as libvpx expects a function with this
signature.

+                                     vpx_codec_frame_buffer* fb);
+
  private:
   enum DecoderState {
     kUninitialized,
     kNormal,
     kFlushCodec,
     kDecodeFinished,
     kError
   };
 
+  // Maximum number of frame buffers allowed to be used by libvpx for VP9
+  // decoding. 8 (libvpx reference buffers) + 4 (jitter buffers) + 1 (work
+  // buffer) = 13.

[fgalligan1, 2013/12/17 01:16:54]

These have to be static const int.

[vignesh, 2013/12/17 18:24:25]

Done.

+  const int kVP9MaxFrameBuffers = 13;

[fgalligan1, 2013/12/17 01:16:54]

I think you can move this to the .cc file. Or are you planning on accessing this
value somewhere else?

I think it would be good if you include media/base/limits.h, so this can be 9
(ref buffers + work buffer) + kMaxVideoFrames;

[vignesh, 2013/12/17 18:24:25]

Done.

+
+  // Minimum libvpx decoder ABI version required to support direct rendering.
+  const int kVP9MinABIVersion = 6;

[fgalligan1, 2013/12/17 01:16:54]

Move this to the .cc and I would change the name to something like
kLibvpxMinAbiExternalBuffers.

[vignesh, 2013/12/17 18:24:25]

Done.

+
   // Handles (re-)initializing the decoder with a (new) config.
   // Returns true when initialization was successful.
   bool ConfigureDecoder(const VideoDecoderConfig& config);
 
   void CloseDecoder();
 
   void DecodeBuffer(const scoped_refptr<DecoderBuffer>& buffer);
   bool VpxDecode(const scoped_refptr<DecoderBuffer>& buffer,
                  scoped_refptr<VideoFrame>* video_frame);
 
@@ skipping 13 matching lines @@
   DecodeCB decode_cb_;
   base::Closure reset_cb_;
 
   VideoDecoderConfig config_;
 
   vpx_codec_ctx* vpx_codec_;
   vpx_codec_ctx* vpx_codec_alpha_;
 
   VideoFramePool frame_pool_;
 
+  // Frame Buffers used for VP9 decoding.
+  vpx_codec_frame_buffer* frame_buffers_;
+
   DISALLOW_COPY_AND_ASSIGN(VpxVideoDecoder);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_VPX_VIDEO_DECODER_H_