media/base/stream_parser.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_BASE_STREAM_PARSER_H_
   6 #define MEDIA_BASE_STREAM_PARSER_H_
   7
   8 #include <deque>
   9 #include <string>
  10
  11 #include "base/callback_forward.h"
  12 #include "base/memory/ref_counted.h"
  13 #include "base/memory/scoped_ptr.h"
  14 #include "base/time.h"
  15 #include "media/base/media_export.h"
  16
  17 namespace media {
  18
  19 class AudioDecoderConfig;
  20 class StreamParserBuffer;
  21 class VideoDecoderConfig;
  22
  23 // Abstract interface for parsing media byte streams.
  24 class MEDIA_EXPORT StreamParser {
  25  public:
  26   typedef std::deque<scoped_refptr<StreamParserBuffer> > BufferQueue;
  27
  28   StreamParser();
  29   virtual ~StreamParser();
  30
  31   // Indicates completion of parser initialization.
  32   // First parameter - Indicates initialization success. Set to true if
  33   //                   initialization was successful. False if an error
  34   //                   occurred.
  35   // Second parameter -  Indicates the stream duration. Only contains a valid
  36   //                     value if the first parameter is true.
  37   typedef base::Callback<void(bool, base::TimeDelta)> InitCB;
  38
  39   // Indicates when new stream configurations have been parsed.
  40   // First parameter - The new audio configuration. If the config is not valid
  41   //                   then it means that there isn't an audio stream.
  42   // Second parameter - The new video configuration. If the config is not valid
  43   //                    then it means that there isn't an audio stream.
  44   // Return value - True if the new configurations are accepted.
  45   //                False if the new configurations are not supported
  46   //                and indicates that a parsing error should be signalled.
  47   typedef base::Callback<bool(const AudioDecoderConfig&,
  48                               const VideoDecoderConfig&)> NewConfigCB;
  49
  50   // New stream buffers have been parsed.
  51   // First parameter - A queue of newly parsed buffers.
  52   // Return value - True indicates that the buffers are accepted.
  53   //                False if something was wrong with the buffers and a parsing
  54   //                error should be signalled.
  55   typedef base::Callback<bool(const BufferQueue&)> NewBuffersCB;
  56
  57   // Signals the beginning of a new media segment.
  58   // First parameter - The earliest timestamp of all the streams in the segment.
  59   typedef base::Callback<void(base::TimeDelta)> NewMediaSegmentCB;
  60
  61   // A new potentially encrypted stream has been parsed.
  62   // First parameter - The type of the initialization data associated with the
  63   //                   stream.
  64   // Second parameter - The initialization data associated with the stream.
  65   // Third parameter - Number of bytes of the initialization data.
  66   // Return value - True indicates that the initialization data is accepted.
  67   //                False if something was wrong with the initialization data
  68   //                and a parsing error should be signalled.
  69   typedef base::Callback<bool(const std::string&,
  70                               scoped_array<uint8>, int)> NeedKeyCB;
  71
  72   // Initialize the parser with necessary callbacks. Must be called before any
  73   // data is passed to Parse(). |init_cb| will be called once enough data has
  74   // been parsed to determine the initial stream configurations, presentation
  75   // start time, and duration.
  76   virtual void Init(const InitCB& init_cb,
  77                     const NewConfigCB& config_cb,
  78                     const NewBuffersCB& audio_cb,
  79                     const NewBuffersCB& video_cb,
  80                     const NeedKeyCB& need_key_cb,
  81                     const NewMediaSegmentCB& new_segment_cb,
  82                     const base::Closure& end_of_segment_cb) = 0;
  83
  84   // Called when a seek occurs. This flushes the current parser state
  85   // and puts the parser in a state where it can receive data for the new seek
  86   // point.
  87   virtual void Flush() = 0;
  88
  89   // Called when there is new data to parse.
  90   //
  91   // Returns true if the parse succeeds.
  92   virtual bool Parse(const uint8* buf, int size) = 0;
  93
  94  private:
  95   DISALLOW_COPY_AND_ASSIGN(StreamParser);
  96 };
  97
  98 }  // namespace media
  99
 100 #endif  // MEDIA_BASE_STREAM_PARSER_H_