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#include "media/base/video_rotation.h"
12
13namespace media {
14
15class AudioDecoderConfig;
16class DecoderBuffer;
17class VideoDecoderConfig;
18
19class MEDIA_EXPORT DemuxerStream {
20 public:
21  enum Type {
22    UNKNOWN,
23    AUDIO,
24    VIDEO,
25    TEXT,
26    NUM_TYPES,  // Always keep this entry as the last one!
27  };
28
29  // Status returned in the Read() callback.
30  //  kOk : Indicates the second parameter is Non-NULL and contains media data
31  //        or the end of the stream.
32  //  kAborted : Indicates an aborted Read(). This can happen if the
33  //             DemuxerStream gets flushed and doesn't have any more data to
34  //             return. The second parameter MUST be NULL when this status is
35  //             returned.
36  //  kConfigChange : Indicates that the AudioDecoderConfig or
37  //                  VideoDecoderConfig for the stream has changed.
38  //                  The DemuxerStream expects an audio_decoder_config() or
39  //                  video_decoder_config() call before Read() will start
40  //                  returning DecoderBuffers again. The decoder will need this
41  //                  new configuration to properly decode the buffers read
42  //                  from this point forward. The second parameter MUST be NULL
43  //                  when this status is returned.
44  //                  This will only be returned if SupportsConfigChanges()
45  //                  returns 'true' for this DemuxerStream.
46  enum Status {
47    kOk,
48    kAborted,
49    kConfigChanged,
50  };
51
52  // Request a buffer to returned via the provided callback.
53  //
54  // The first parameter indicates the status of the read.
55  // The second parameter is non-NULL and contains media data
56  // or the end of the stream if the first parameter is kOk. NULL otherwise.
57  typedef base::Callback<void(Status,
58                              const scoped_refptr<DecoderBuffer>&)>ReadCB;
59  virtual void Read(const ReadCB& read_cb) = 0;
60
61  // Returns the audio decoder configuration. It is an error to call this method
62  // if type() != AUDIO.
63  virtual AudioDecoderConfig audio_decoder_config() = 0;
64
65  // Returns the video decoder configuration. It is an error to call this method
66  // if type() != VIDEO.
67  virtual VideoDecoderConfig video_decoder_config() = 0;
68
69  // Returns the type of stream.
70  virtual Type type() = 0;
71
72  virtual void EnableBitstreamConverter();
73
74  // Whether or not this DemuxerStream allows midstream configuration changes.
75  //
76  // A DemuxerStream that returns 'true' to this may return the 'kConfigChange'
77  // status from a Read() call. In this case the client is expected to be
78  // capable of taking appropriate action to handle config changes. Otherwise
79  // audio_decoder_config() and video_decoder_config()'s return values are
80  // guaranteed to remain constant, and the client may make optimizations based
81  // on this.
82  virtual bool SupportsConfigChanges() = 0;
83
84  virtual VideoRotation video_rotation() = 0;
85
86 protected:
87  // Only allow concrete implementations to get deleted.
88  virtual ~DemuxerStream();
89};
90
91}  // namespace media
92
93#endif  // MEDIA_BASE_DEMUXER_STREAM_H_
94