Mpeg2 TS stream parser for media source.

media/mpeg2/es_parser_adts.h

+// Copyright (c) 2013 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_MPEG2_ES_PARSER_ADTS_H_
+#define MEDIA_MPEG2_ES_PARSER_ADTS_H_
+
+#include <list>
+#include <utility>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/callback.h"
+#include "base/compiler_specific.h"
+#include "base/memory/ref_counted.h"
+#include "base/time/time.h"
+#include "media/base/byte_queue.h"
+#include "media/mpeg2/es_parser.h"
+
+namespace media {
+class BitReader;
+class AudioDecoderConfig;
+class StreamParserBuffer;
+}
+
+namespace media {
+namespace mpeg2ts {
+
+class EsParserAdts : public EsParser {
+ public:
+  typedef base::Callback<void(const AudioDecoderConfig&)> NewAudioConfigCB;
+  typedef base::Callback<void(scoped_refptr<StreamParserBuffer>)> EmitBufferCB;
+
+  EsParserAdts(NewAudioConfigCB new_audio_config_cb,
+               EmitBufferCB emit_buffer_cb);
+  virtual ~EsParserAdts();
+
+  // EsParser implementation.
+  virtual void Parse(const uint8* buf, int size,
+                     base::TimeDelta pts,
+                     base::TimeDelta dts) OVERRIDE;
+  virtual void Flush() OVERRIDE;
+
+ private:
+  // Used to link a PTS with a byte position in the ES stream.
+  typedef std::pair<int, base::TimeDelta> EsPts;
+  typedef std::list<EsPts> EsPtsList;
+
+  // Signal any audio configuration change (if any).
+  void UpdateAudioConfiguration(const uint8* adts_header);
+
+  // Discard some bytes from the ES stream.
+  void DiscardEs(int nbytes);
+
+  // Callbacks:
+  // - to signal a new audio configuration,
+  // - to send ES buffers.
+  NewAudioConfigCB new_audio_config_cb_;
+  EmitBufferCB emit_buffer_cb_;
+
+  // Bytes of the ES stream that have not been emitted yet.
+  ByteQueue es_byte_queue_;
+
+  // List of PTS associated with a position in the ES stream.
+  EsPtsList pts_list_;
+
+  // Interpolated PTS for frames that don't have one.
+  base::TimeDelta estimated_pts_;
+
+  bool first_frame_;
+  base::TimeDelta last_frame_pts_;
+
+  // Last audio config.
+  bool is_audio_config_known_;
+  int sampling_frequency_;
+  int channel_configuration_;
+
+  DISALLOW_COPY_AND_ASSIGN(EsParserAdts);
+};
+
+}  // namespace mpeg2ts
+}  // namespace media
+
+#endif
+