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 13 namespace media { 14 15 class AudioDecoderConfig; 16 class DecoderBuffer; 17 class VideoDecoderConfig; 18 19 class 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