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