Mpeg2 TS parser: Es parsing using an ES byte queue.

media/formats/mp2t/es_parser_h264.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_FORMATS_MP2T_ES_PARSER_H264_H_
 #define MEDIA_FORMATS_MP2T_ES_PARSER_H264_H_
 
 #include <list>
 #include <utility>
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/time/time.h"
 #include "media/base/media_export.h"
 #include "media/base/video_decoder_config.h"
 #include "media/formats/mp2t/es_adapter_video.h"
 #include "media/formats/mp2t/es_parser.h"
 
 namespace media {
 class H264Parser;
 struct H264SPS;
 class OffsetByteQueue;
 }
 
 namespace media {
 namespace mp2t {
 
-// Remark:
-// In this h264 parser, frame splitting is based on AUD nals.
+// A few remarks:
+// - In this h264 parser, frame splitting is based on AUD nals.
 // Mpeg2 TS spec: "2.14 Carriage of Rec. ITU-T H.264 | ISO/IEC 14496-10 video"
 // "Each AVC access unit shall contain an access unit delimiter NAL Unit;"
+// - PES packets do not necessarily map to an H264 access unit although the HLS
+// recommendation is to use one PES for each access unit. In this parser,
+// we handle the general case and do not make any assumption about the access
+// unit organization within PES packets.
 //
 class MEDIA_EXPORT EsParserH264 : public EsParser {
  public:
   typedef base::Callback<void(const VideoDecoderConfig&)> NewVideoConfigCB;
 
   EsParserH264(const NewVideoConfigCB& new_video_config_cb,
                const EmitBufferCB& emit_buffer_cb);
   virtual ~EsParserH264();
 
   // EsParser implementation.
-  virtual bool Parse(const uint8* buf, int size,
-                     base::TimeDelta pts,
-                     DecodeTimestamp dts) OVERRIDE;
   virtual void Flush() OVERRIDE;
-  virtual void Reset() OVERRIDE;
 
  private:
-  struct TimingDesc {
-    DecodeTimestamp dts;
-    base::TimeDelta pts;
-  };
+  // EsParser implementation.
+  virtual bool ParseFromEsQueue() OVERRIDE;
+  virtual void ResetInternal() OVERRIDE;
 
   // Find the AUD located at or after |*stream_pos|.
   // Return true if an AUD is found.
   // If found, |*stream_pos| corresponds to the position of the AUD start code
   // in the stream. Otherwise, |*stream_pos| corresponds to the last position
   // of the start code parser.
   bool FindAUD(int64* stream_pos);
 
-  // Resumes the H264 ES parsing.
-  // Return true if successful.
-  bool ParseInternal();
-
   // Emit a frame whose position in the ES queue starts at |access_unit_pos|.
   // Returns true if successful, false if no PTS is available for the frame.
   bool EmitFrame(int64 access_unit_pos, int access_unit_size,
                  bool is_key_frame, int pps_id);
 
   // Update the video decoder config based on an H264 SPS.
   // Return true if successful.
   bool UpdateVideoDecoderConfig(const H264SPS* sps);
 
   EsAdapterVideo es_adapter_;
 
-  // Bytes of the ES stream that have not been emitted yet.
-  scoped_ptr<media::OffsetByteQueue> es_queue_;
-  std::list<std::pair<int64, TimingDesc> > timing_desc_list_;
-
   // H264 parser state.
   // - |current_access_unit_pos_| is pointing to an annexB syncword
   // representing the first NALU of an H264 access unit.
   scoped_ptr<H264Parser> h264_parser_;
   int64 current_access_unit_pos_;
   int64 next_access_unit_pos_;
 
   // Last video decoder config.
   VideoDecoderConfig last_video_decoder_config_;
 
   DISALLOW_COPY_AND_ASSIGN(EsParserH264);
 };
 
 }  // namespace mp2t
 }  // namespace media
 
 #endif