media/formats/mp2t/es_adapter_video.h

   1 // Copyright 2014 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_FORMATS_MP2T_ES_ADAPTER_VIDEO_H_
   6 #define MEDIA_FORMATS_MP2T_ES_ADAPTER_VIDEO_H_
   7
   8 #include <deque>
   9 #include <list>
  10 #include <utility>
  11
  12 #include "base/callback.h"
  13 #include "base/memory/ref_counted.h"
  14 #include "base/time/time.h"
  15 #include "media/base/media_export.h"
  16
  17 namespace media {
  18 class StreamParserBuffer;
  19 class VideoDecoderConfig;
  20
  21 namespace mp2t {
  22
  23 // Some constraints of the MSE spec are not necessarily met by video streams
  24 // inside an Mpeg2 TS stream.
  25 // The goal of the ES adapter is to modify the incoming buffers to meet these
  26 // constraints, e.g.
  27 // - get the frame duration,
  28 // - replace the leading non-key frames by the first key frame to avoid
  29 //   creating a hole in the video timeline.
  30 class MEDIA_EXPORT EsAdapterVideo {
  31  public:
  32   typedef base::Callback<void(const VideoDecoderConfig&)> NewVideoConfigCB;
  33   typedef base::Callback<void(scoped_refptr<StreamParserBuffer>)> EmitBufferCB;
  34
  35   EsAdapterVideo(
  36       const NewVideoConfigCB& new_video_config_cb,
  37       const EmitBufferCB& emit_buffer_cb);
  38   ~EsAdapterVideo();
  39
  40   // Force the emission of the pending video buffers.
  41   void Flush();
  42
  43   // Reset the ES adapter to its initial state.
  44   void Reset();
  45
  46   // Provide the configuration that applies to the upcoming video buffers.
  47   void OnConfigChanged(const VideoDecoderConfig& video_decoder_config);
  48
  49   // Provide a new video buffer.
  50   void OnNewBuffer(
  51       const scoped_refptr<StreamParserBuffer>& stream_parser_buffer);
  52
  53  private:
  54   typedef std::deque<scoped_refptr<StreamParserBuffer> > BufferQueue;
  55   typedef std::pair<int64, VideoDecoderConfig> ConfigEntry;
  56
  57   void ProcessPendingBuffers(bool flush);
  58
  59   // Return the PTS of the frame that comes just after |current_pts| in
  60   // presentation order. Return kNoTimestamp() if not found.
  61   base::TimeDelta GetNextFramePts(base::TimeDelta current_pts);
  62
  63   // Replace the leading non key frames by |stream_parser_buffer|
  64   // (this one must be a key frame).
  65   void ReplaceDiscardedFrames(
  66       const scoped_refptr<StreamParserBuffer>& stream_parser_buffer);
  67
  68   NewVideoConfigCB new_video_config_cb_;
  69   EmitBufferCB emit_buffer_cb_;
  70
  71   bool has_valid_config_;
  72   bool has_valid_frame_;
  73
  74   // Duration of the last video frame.
  75   base::TimeDelta last_frame_duration_;
  76
  77   // Association between a video config and a buffer index.
  78   std::list<ConfigEntry> config_list_;
  79
  80   // Global index of the first buffer in |buffer_list_|.
  81   int64 buffer_index_;
  82
  83   // List of buffer to be emitted and PTS of frames already emitted.
  84   BufferQueue buffer_list_;
  85   std::list<base::TimeDelta> emitted_pts_;
  86
  87   // - Minimum PTS of discarded frames.
  88   // - DTS of discarded frames.
  89   base::TimeDelta discarded_frames_min_pts_;
  90   std::list<base::TimeDelta> discarded_frames_dts_;
  91
  92   DISALLOW_COPY_AND_ASSIGN(EsAdapterVideo);
  93 };
  94
  95 }  // namespace mp2t
  96 }  // namespace media
  97
  98 #endif  // MEDIA_FORMATS_MP2T_ES_ADAPTER_VIDEO_H_