Add libvpx wrapper to media to support VP9 video decoding.

media/filters/vpx_video_decoder.h

Index: media/filters/vpx_video_decoder.h
diff --git a/media/filters/ffmpeg_video_decoder.h b/media/filters/vpx_video_decoder.h
similarity index 59%
copy from media/filters/ffmpeg_video_decoder.h
copy to media/filters/vpx_video_decoder.h
index e26a1943d7aa0859a533f1e45621c73ec1aa9a02..77578fdc90f7e6c82de90090cadff43857e1a886 100644
--- a/media/filters/ffmpeg_video_decoder.h
+++ b/media/filters/vpx_video_decoder.h
@@ -2,16 +2,16 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef MEDIA_FILTERS_FFMPEG_VIDEO_DECODER_H_
-#define MEDIA_FILTERS_FFMPEG_VIDEO_DECODER_H_
+#ifndef MEDIA_FILTERS_VPX_VIDEO_DECODER_H_
+#define MEDIA_FILTERS_VPX_VIDEO_DECODER_H_
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "media/base/demuxer_stream.h"
 #include "media/base/video_decoder.h"
 
-struct AVCodecContext;
-struct AVFrame;
+struct vpx_codec_ctx;
+struct vpx_image;
 
 namespace base {
 class MessageLoopProxy;
@@ -19,11 +19,9 @@ class MessageLoopProxy;
 
 namespace media {
 
-class DecoderBuffer;
-
-class MEDIA_EXPORT FFmpegVideoDecoder : public VideoDecoder {
+class MEDIA_EXPORT VpxVideoDecoder : public VideoDecoder {
  public:
-  explicit FFmpegVideoDecoder(
+  explicit VpxVideoDecoder(
       const scoped_refptr<base::MessageLoopProxy>& message_loop);
 
   // VideoDecoder implementation.
@@ -34,13 +32,8 @@ class MEDIA_EXPORT FFmpegVideoDecoder : public VideoDecoder {
   virtual void Reset(const base::Closure& closure) OVERRIDE;
   virtual void Stop(const base::Closure& closure) OVERRIDE;
 
-  // Callback called from within FFmpeg to allocate a buffer based on
-  // the dimensions of |codec_context|. See AVCodecContext.get_buffer
-  // documentation inside FFmpeg.
-  int GetVideoBuffer(AVCodecContext *codec_context, AVFrame* frame);
-
  protected:
-  virtual ~FFmpegVideoDecoder();
+  virtual ~VpxVideoDecoder();
 
  private:
   enum DecoderState {
@@ -50,46 +43,44 @@ class MEDIA_EXPORT FFmpegVideoDecoder : public VideoDecoder {
     kDecodeFinished
   };
 
-  // Reads from the demuxer stream and corresponding read callback.
+  // Handles (re-)initializing the decoder with a (new) config.
+  // Returns true when initialization was successful.
+  bool ConfigureDecoder();
+
+  void CloseDecoder();
   void ReadFromDemuxerStream();
-  void BufferReady(DemuxerStream::Status status,
-                   const scoped_refptr<DecoderBuffer>& buffer);
 
-  // Handles decoding an unencrypted encoded buffer.
+  // Carries out the buffer processing operation scheduled by
+  // DecryptOrDecodeBuffer().
+  void DoDecryptOrDecodeBuffer(DemuxerStream::Status status,
+                               const scoped_refptr<DecoderBuffer>& buffer);
+
   void DecodeBuffer(const scoped_refptr<DecoderBuffer>& buffer);
   bool Decode(const scoped_refptr<DecoderBuffer>& buffer,
               scoped_refptr<VideoFrame>* video_frame);
 
-  // Handles (re-)initializing the decoder with a (new) config.
-  // Returns true if initialization was successful.
-  bool ConfigureDecoder();
-
-  // Releases resources associated with |codec_context_| and |av_frame_|
-  // and resets them to NULL.
-  void ReleaseFFmpegResources();
-
   // Reset decoder and call |reset_cb_|.
   void DoReset();
 
+  void CopyVpxImageTo(const vpx_image* vpx_image,
+                      scoped_refptr<VideoFrame>* video_frame);
+
   scoped_refptr<base::MessageLoopProxy> message_loop_;
 
   DecoderState state_;
 
   StatisticsCB statistics_cb_;
-
   ReadCB read_cb_;
   base::Closure reset_cb_;
 
-  // FFmpeg structures owned by this object.
-  AVCodecContext* codec_context_;
-  AVFrame* av_frame_;
-
   // Pointer to the demuxer stream that will feed us compressed buffers.
   scoped_refptr<DemuxerStream> demuxer_stream_;
 
-  DISALLOW_COPY_AND_ASSIGN(FFmpegVideoDecoder);
+  vpx_codec_ctx* vpx_codec_;
+
+  DISALLOW_COPY_AND_ASSIGN(VpxVideoDecoder);
 };
 
 }  // namespace media
 
-#endif  // MEDIA_FILTERS_FFMPEG_VIDEO_DECODER_H_
+#endif  // MEDIA_FILTERS_VPX_VIDEO_DECODER_H_