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 #include "media/base/video_frame_pool.h"
  16
  17 struct AVCodecContext;
  18 struct AVFrame;
  19
  20 namespace base {
  21 class SingleThreadTaskRunner;
  22 }
  23
  24 namespace media {
  25
  26 class DecoderBuffer;
  27 class ScopedPtrAVFreeContext;
  28 class ScopedPtrAVFreeFrame;
  29
  30 class MEDIA_EXPORT FFmpegVideoDecoder : public VideoDecoder {
  31  public:
  32   explicit FFmpegVideoDecoder(
  33       const scoped_refptr<base::SingleThreadTaskRunner>& task_runner);
  34   virtual ~FFmpegVideoDecoder();
  35
  36   // VideoDecoder implementation.
  37   virtual void Initialize(const VideoDecoderConfig& config,
  38                           const PipelineStatusCB& status_cb) OVERRIDE;
  39   virtual void Decode(const scoped_refptr<DecoderBuffer>& buffer,
  40                       const DecodeCB& decode_cb) OVERRIDE;
  41   virtual void Reset(const base::Closure& closure) OVERRIDE;
  42   virtual void Stop(const base::Closure& closure) OVERRIDE;
  43
  44   // Callback called from within FFmpeg to allocate a buffer based on
  45   // the dimensions of |codec_context|. See AVCodecContext.get_buffer
  46   // documentation inside FFmpeg.
  47   int GetVideoBuffer(AVCodecContext *codec_context, AVFrame* frame);
  48
  49  private:
  50   enum DecoderState {
  51     kUninitialized,
  52     kNormal,
  53     kFlushCodec,
  54     kDecodeFinished,
  55     kError
  56   };
  57
  58   // Handles decoding an unencrypted encoded buffer.
  59   void DecodeBuffer(const scoped_refptr<DecoderBuffer>& buffer);
  60   bool FFmpegDecode(const scoped_refptr<DecoderBuffer>& buffer,
  61                     scoped_refptr<VideoFrame>* video_frame);
  62
  63   // Handles (re-)initializing the decoder with a (new) config.
  64   // Returns true if initialization was successful.
  65   bool ConfigureDecoder();
  66
  67   // Releases resources associated with |codec_context_| and |av_frame_|
  68   // and resets them to NULL.
  69   void ReleaseFFmpegResources();
  70
  71   // Reset decoder and call |reset_cb_|.
  72   void DoReset();
  73
  74   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
  75   base::WeakPtrFactory<FFmpegVideoDecoder> weak_factory_;
  76   base::WeakPtr<FFmpegVideoDecoder> weak_this_;
  77
  78   DecoderState state_;
  79
  80   DecodeCB decode_cb_;
  81   base::Closure reset_cb_;
  82
  83   // FFmpeg structures owned by this object.
  84   scoped_ptr_malloc<AVCodecContext, ScopedPtrAVFreeContext> codec_context_;
  85   scoped_ptr_malloc<AVFrame, ScopedPtrAVFreeFrame> av_frame_;
  86
  87   VideoDecoderConfig config_;
  88
  89   VideoFramePool frame_pool_;
  90
  91   DISALLOW_COPY_AND_ASSIGN(FFmpegVideoDecoder);
  92 };
  93
  94 }  // namespace media
  95
  96 #endif  // MEDIA_FILTERS_FFMPEG_VIDEO_DECODER_H_