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