media/filters/vpx_video_decoder.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef MEDIA_FILTERS_VPX_VIDEO_DECODER_H_
   6 #define MEDIA_FILTERS_VPX_VIDEO_DECODER_H_
   7
   8 #include "base/callback.h"
   9 #include "base/memory/weak_ptr.h"
  10 #include "media/base/demuxer_stream.h"
  11 #include "media/base/video_decoder.h"
  12 #include "media/base/video_decoder_config.h"
  13 #include "media/base/video_frame.h"
  14
  15 struct vpx_codec_ctx;
  16 struct vpx_image;
  17
  18 namespace base {
  19 class MessageLoopProxy;
  20 }
  21
  22 namespace media {
  23
  24 // Libvpx video decoder wrapper.
  25 // Note: VpxVideoDecoder accepts only YV12A VP8 content or VP9 content. This is
  26 // done to avoid usurping FFmpeg for all vp8 decoding, because the FFmpeg VP8
  27 // decoder is faster than the libvpx VP8 decoder.
  28 class MEDIA_EXPORT VpxVideoDecoder : public VideoDecoder {
  29  public:
  30   explicit VpxVideoDecoder(
  31       const scoped_refptr<base::MessageLoopProxy>& message_loop);
  32   virtual ~VpxVideoDecoder();
  33
  34   // VideoDecoder implementation.
  35   virtual void Initialize(const VideoDecoderConfig& config,
  36                           const PipelineStatusCB& status_cb) OVERRIDE;
  37   virtual void Decode(const scoped_refptr<DecoderBuffer>& buffer,
  38                       const DecodeCB& decode_cb) OVERRIDE;
  39   virtual void Reset(const base::Closure& closure) OVERRIDE;
  40   virtual void Stop(const base::Closure& closure) OVERRIDE;
  41   virtual bool HasAlpha() const OVERRIDE;
  42
  43  private:
  44   enum DecoderState {
  45     kUninitialized,
  46     kNormal,
  47     kFlushCodec,
  48     kDecodeFinished,
  49     kError
  50   };
  51
  52   // Handles (re-)initializing the decoder with a (new) config.
  53   // Returns true when initialization was successful.
  54   bool ConfigureDecoder(const VideoDecoderConfig& config);
  55
  56   void CloseDecoder();
  57
  58   void DecodeBuffer(const scoped_refptr<DecoderBuffer>& buffer);
  59   bool VpxDecode(const scoped_refptr<DecoderBuffer>& buffer,
  60                  scoped_refptr<VideoFrame>* video_frame);
  61
  62   // Reset decoder and call |reset_cb_|.
  63   void DoReset();
  64
  65   void CopyVpxImageTo(const vpx_image* vpx_image,
  66                       const struct vpx_image* vpx_image_alpha,
  67                       scoped_refptr<VideoFrame>* video_frame);
  68
  69   scoped_refptr<base::MessageLoopProxy> message_loop_;
  70   base::WeakPtrFactory<VpxVideoDecoder> weak_factory_;
  71   base::WeakPtr<VpxVideoDecoder> weak_this_;
  72
  73   DecoderState state_;
  74
  75   DecodeCB decode_cb_;
  76   base::Closure reset_cb_;
  77
  78   VideoDecoderConfig config_;
  79
  80   vpx_codec_ctx* vpx_codec_;
  81   vpx_codec_ctx* vpx_codec_alpha_;
  82
  83   DISALLOW_COPY_AND_ASSIGN(VpxVideoDecoder);
  84 };
  85
  86 }  // namespace media
  87
  88 #endif  // MEDIA_FILTERS_VPX_VIDEO_DECODER_H_