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   // Allow decoding of individual NALU. Entire frames are required by default.
  35   // Disables low-latency mode. Must be called before Initialize().
  36   void set_decode_nalus(bool decode_nalus) { decode_nalus_ = decode_nalus; }
  37
  38   // VideoDecoder implementation.
  39   virtual void Initialize(const VideoDecoderConfig& config,
  40                           bool low_delay,
  41                           const PipelineStatusCB& status_cb,
  42                           const OutputCB& output_cb) OVERRIDE;
  43   virtual void Decode(const scoped_refptr<DecoderBuffer>& buffer,
  44                       const DecodeCB& decode_cb) OVERRIDE;
  45   virtual void Reset(const base::Closure& closure) OVERRIDE;
  46
  47   // Callback called from within FFmpeg to allocate a buffer based on
  48   // the dimensions of |codec_context|. See AVCodecContext.get_buffer2
  49   // documentation inside FFmpeg.
  50   int GetVideoBuffer(struct AVCodecContext* codec_context,
  51                      AVFrame* frame,
  52                      int flags);
  53
  54  private:
  55   enum DecoderState {
  56     kUninitialized,
  57     kNormal,
  58     kDecodeFinished,
  59     kError
  60   };
  61
  62   // Handles decoding an unencrypted encoded buffer.
  63   bool FFmpegDecode(const scoped_refptr<DecoderBuffer>& buffer,
  64                     bool* has_produced_frame);
  65
  66   // Handles (re-)initializing the decoder with a (new) config.
  67   // Returns true if initialization was successful.
  68   bool ConfigureDecoder(bool low_delay);
  69
  70   // Releases resources associated with |codec_context_| and |av_frame_|
  71   // and resets them to NULL.
  72   void ReleaseFFmpegResources();
  73
  74   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
  75
  76   DecoderState state_;
  77
  78   OutputCB output_cb_;
  79
  80   // FFmpeg structures owned by this object.
  81   scoped_ptr<AVCodecContext, ScopedPtrAVFreeContext> codec_context_;
  82   scoped_ptr<AVFrame, ScopedPtrAVFreeFrame> av_frame_;
  83
  84   VideoDecoderConfig config_;
  85
  86   VideoFramePool frame_pool_;
  87
  88   bool decode_nalus_;
  89
  90   DISALLOW_COPY_AND_ASSIGN(FFmpegVideoDecoder);
  91 };
  92
  93 }  // namespace media
  94
  95 #endif  // MEDIA_FILTERS_FFMPEG_VIDEO_DECODER_H_