media/base/demuxer_stream.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_DEMUXER_STREAM_H_
   6 #define MEDIA_BASE_DEMUXER_STREAM_H_
   7
   8 #include "base/callback.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "media/base/media_export.h"
  11
  12 namespace media {
  13
  14 class AudioDecoderConfig;
  15 class DecoderBuffer;
  16 class VideoDecoderConfig;
  17
  18 class MEDIA_EXPORT DemuxerStream {
  19  public:
  20   enum Type {
  21     UNKNOWN,
  22     AUDIO,
  23     VIDEO,
  24     NUM_TYPES,  // Always keep this entry as the last one!
  25   };
  26
  27   // Status returned in the Read() callback.
  28   //  kOk : Indicates the second parameter is Non-NULL and contains media data
  29   //        or the end of the stream.
  30   //  kAborted : Indicates an aborted Read(). This can happen if the
  31   //             DemuxerStream gets flushed and doesn't have any more data to
  32   //             return. The second parameter MUST be NULL when this status is
  33   //             returned.
  34   //  kConfigChange : Indicates that the AudioDecoderConfig or
  35   //                  VideoDecoderConfig for the stream has changed.
  36   //                  The DemuxerStream expects an audio_decoder_config() or
  37   //                  video_decoder_config() call before Read() will start
  38   //                  returning DecoderBuffers again. The decoder will need this
  39   //                  new configuration to properly decode the buffers read
  40   //                  from this point forward. The second parameter MUST be NULL
  41   //                  when this status is returned.
  42   enum Status {
  43     kOk,
  44     kAborted,
  45     kConfigChanged,
  46   };
  47
  48   // Request a buffer to returned via the provided callback.
  49   //
  50   // The first parameter indicates the status of the read.
  51   // The second parameter is non-NULL and contains media data
  52   // or the end of the stream if the first parameter is kOk. NULL otherwise.
  53   typedef base::Callback<void(Status,
  54                               const scoped_refptr<DecoderBuffer>&)>ReadCB;
  55   virtual void Read(const ReadCB& read_cb) = 0;
  56
  57   // Returns the audio decoder configuration. It is an error to call this method
  58   // if type() != AUDIO.
  59   virtual AudioDecoderConfig audio_decoder_config() = 0;
  60
  61   // Returns the video decoder configuration. It is an error to call this method
  62   // if type() != VIDEO.
  63   virtual VideoDecoderConfig video_decoder_config() = 0;
  64
  65   // Returns the type of stream.
  66   virtual Type type() = 0;
  67
  68   virtual void EnableBitstreamConverter() = 0;
  69
  70  protected:
  71   // Only allow concrete implementations to get deleted.
  72   virtual ~DemuxerStream();
  73 };
  74
  75 }  // namespace media
  76
  77 #endif  // MEDIA_BASE_DEMUXER_STREAM_H_