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 "media/base/video_decoder.h"
  13 #include "media/base/video_decoder_config.h"
  14 #include "media/base/video_frame_pool.h"
  15 #include "media/ffmpeg/ffmpeg_deleters.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
  28 class MEDIA_EXPORT FFmpegVideoDecoder : public VideoDecoder {
  29  public:
  30   explicit FFmpegVideoDecoder(
  31       const scoped_refptr<base::SingleThreadTaskRunner>& task_runner);
  32   virtual ~FFmpegVideoDecoder();
  33
  34   // VideoDecoder implementation.
  35   virtual void Initialize(const VideoDecoderConfig& config,
  36                           bool low_delay,
  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() 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(bool low_delay);
  65
  66   // Releases resources associated with |codec_context_| and |av_frame_|
  67   // and resets them to NULL.
  68   void ReleaseFFmpegResources();
  69
  70   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
  71
  72   DecoderState state_;
  73
  74   // TODO(xhwang): Merge DecodeBuffer() into Decode() and remove this.
  75   DecodeCB decode_cb_;
  76
  77   // FFmpeg structures owned by this object.
  78   scoped_ptr<AVCodecContext, ScopedPtrAVFreeContext> codec_context_;
  79   scoped_ptr<AVFrame, ScopedPtrAVFreeFrame> av_frame_;
  80
  81   VideoDecoderConfig config_;
  82
  83   VideoFramePool frame_pool_;
  84
  85   DISALLOW_COPY_AND_ASSIGN(FFmpegVideoDecoder);
  86 };
  87
  88 }  // namespace media
  89
  90 #endif  // MEDIA_FILTERS_FFMPEG_VIDEO_DECODER_H_