media/filters/ffmpeg_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_FFMPEG_VIDEO_DECODER_H_
   6 #define MEDIA_FILTERS_FFMPEG_VIDEO_DECODER_H_
   7
   8 #include <list>
   9
  10 #include "base/callback.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/memory/weak_ptr.h"
  13 #include "media/base/video_decoder.h"
  14 #include "media/base/video_decoder_config.h"
  15
  16 struct AVCodecContext;
  17 struct AVFrame;
  18
  19 namespace base {
  20 class MessageLoopProxy;
  21 }
  22
  23 namespace media {
  24
  25 class DecoderBuffer;
  26 class ScopedPtrAVFreeContext;
  27 class ScopedPtrAVFreeFrame;
  28
  29 class MEDIA_EXPORT FFmpegVideoDecoder : public VideoDecoder {
  30  public:
  31   explicit FFmpegVideoDecoder(
  32       const scoped_refptr<base::MessageLoopProxy>& message_loop);
  33   virtual ~FFmpegVideoDecoder();
  34
  35   // VideoDecoder implementation.
  36   virtual void Initialize(const VideoDecoderConfig& config,
  37                           const PipelineStatusCB& status_cb) OVERRIDE;
  38   virtual void Decode(const scoped_refptr<DecoderBuffer>& buffer,
  39                       const DecodeCB& decode_cb) OVERRIDE;
  40   virtual void Reset(const base::Closure& closure) OVERRIDE;
  41   virtual void Stop(const base::Closure& closure) OVERRIDE;
  42
  43   // Callback called from within FFmpeg to allocate a buffer based on
  44   // the dimensions of |codec_context|. See AVCodecContext.get_buffer
  45   // documentation inside FFmpeg.
  46   int GetVideoBuffer(AVCodecContext *codec_context, AVFrame* frame);
  47
  48  private:
  49   enum DecoderState {
  50     kUninitialized,
  51     kNormal,
  52     kFlushCodec,
  53     kDecodeFinished,
  54     kError
  55   };
  56
  57   // Handles decoding an unencrypted encoded buffer.
  58   void DecodeBuffer(const scoped_refptr<DecoderBuffer>& buffer);
  59   bool FFmpegDecode(const scoped_refptr<DecoderBuffer>& buffer,
  60                     scoped_refptr<VideoFrame>* video_frame);
  61
  62   // Handles (re-)initializing the decoder with a (new) config.
  63   // Returns true if initialization was successful.
  64   bool ConfigureDecoder();
  65
  66   // Releases resources associated with |codec_context_| and |av_frame_|
  67   // and resets them to NULL.
  68   void ReleaseFFmpegResources();
  69
  70   // Reset decoder and call |reset_cb_|.
  71   void DoReset();
  72
  73   scoped_refptr<base::MessageLoopProxy> message_loop_;
  74   base::WeakPtrFactory<FFmpegVideoDecoder> weak_factory_;
  75   base::WeakPtr<FFmpegVideoDecoder> weak_this_;
  76
  77   DecoderState state_;
  78
  79   DecodeCB decode_cb_;
  80   base::Closure reset_cb_;
  81
  82   // FFmpeg structures owned by this object.
  83   scoped_ptr_malloc<AVCodecContext, ScopedPtrAVFreeContext> codec_context_;
  84   scoped_ptr_malloc<AVFrame, ScopedPtrAVFreeFrame> av_frame_;
  85
  86   VideoDecoderConfig config_;
  87
  88   DISALLOW_COPY_AND_ASSIGN(FFmpegVideoDecoder);
  89 };
  90
  91 }  // namespace media
  92
  93 #endif  // MEDIA_FILTERS_FFMPEG_VIDEO_DECODER_H_