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   static bool IsCodecSupported(VideoCodec codec);
  31
  32   explicit FFmpegVideoDecoder(
  33       const scoped_refptr<base::SingleThreadTaskRunner>& task_runner);
  34   ~FFmpegVideoDecoder() override;
  35
  36   // Allow decoding of individual NALU. Entire frames are required by default.
  37   // Disables low-latency mode. Must be called before Initialize().
  38   void set_decode_nalus(bool decode_nalus) { decode_nalus_ = decode_nalus; }
  39
  40   // VideoDecoder implementation.
  41   std::string GetDisplayName() const override;
  42   void Initialize(const VideoDecoderConfig& config,
  43                   bool low_delay,
  44                   const InitCB& init_cb,
  45                   const OutputCB& output_cb) override;
  46   void Decode(const scoped_refptr<DecoderBuffer>& buffer,
  47               const DecodeCB& decode_cb) override;
  48   void Reset(const base::Closure& closure) override;
  49
  50   // Callback called from within FFmpeg to allocate a buffer based on
  51   // the dimensions of |codec_context|. See AVCodecContext.get_buffer2
  52   // documentation inside FFmpeg.
  53   int GetVideoBuffer(struct AVCodecContext* codec_context,
  54                      AVFrame* frame,
  55                      int flags);
  56
  57  private:
  58   enum DecoderState {
  59     kUninitialized,
  60     kNormal,
  61     kDecodeFinished,
  62     kError
  63   };
  64
  65   // Handles decoding an unencrypted encoded buffer.
  66   bool FFmpegDecode(const scoped_refptr<DecoderBuffer>& buffer,
  67                     bool* has_produced_frame);
  68
  69   // Handles (re-)initializing the decoder with a (new) config.
  70   // Returns true if initialization was successful.
  71   bool ConfigureDecoder(bool low_delay);
  72
  73   // Releases resources associated with |codec_context_| and |av_frame_|
  74   // and resets them to NULL.
  75   void ReleaseFFmpegResources();
  76
  77   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
  78
  79   DecoderState state_;
  80
  81   OutputCB output_cb_;
  82
  83   // FFmpeg structures owned by this object.
  84   scoped_ptr<AVCodecContext, ScopedPtrAVFreeContext> codec_context_;
  85   scoped_ptr<AVFrame, ScopedPtrAVFreeFrame> av_frame_;
  86
  87   VideoDecoderConfig config_;
  88
  89   VideoFramePool frame_pool_;
  90
  91   bool decode_nalus_;
  92
  93   DISALLOW_COPY_AND_ASSIGN(FFmpegVideoDecoder);
  94 };
  95
  96 }  // namespace media
  97
  98 #endif  // MEDIA_FILTERS_FFMPEG_VIDEO_DECODER_H_