| // Copyright 2016 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_BASE_MEDIA_TRACK_H_ |
| #define MEDIA_BASE_MEDIA_TRACK_H_ |
| |
| #include <string> |
| |
| #include "media/base/media_export.h" |
| #include "media/base/stream_parser.h" |
| |
| namespace media { |
| |
| class MEDIA_EXPORT MediaTrack { |
| public: |
| enum Type { Text, Audio, Video }; |
| using Id = std::string; |
| MediaTrack(Type type, |
| StreamParser::TrackId bytestream_track_id, |
| const std::string& kind, |
| const std::string& label, |
| const std::string& lang); |
| ~MediaTrack(); |
| |
| Type type() const { return type_; } |
| |
| StreamParser::TrackId bytestream_track_id() const { |
| return bytestream_track_id_; |
| } |
| const std::string& kind() const { return kind_; } |
| const std::string& label() const { return label_; } |
| const std::string& language() const { return language_; } |
| |
| Id id() const { return id_; } |
| void set_id(Id id) { |
| DCHECK(id_.empty()); |
| DCHECK(!id.empty()); |
| id_ = id; |
| } |
| |
| private: |
| Type type_; |
| |
| // |bytestream_track_id_| is read from the bytestream and is guaranteed to be |
| // unique only within the scope of single bytestream's initialization segment. |
| // But we might have multiple bytestreams (MediaSource might have multiple |
| // SourceBuffers attached to it, which translates into ChunkDemuxer having |
| // multiple SourceBufferStates and multiple bytestreams) or subsequent init |
| // segments may redefine the bytestream ids. Thus bytestream track ids are not |
| // guaranteed to be unique at the Demuxer and HTMLMediaElement level. So we |
| // generate truly unique media track |id_| on the Demuxer level. |
| StreamParser::TrackId bytestream_track_id_; |
| Id id_; |
| |
| // These properties are read from input streams by stream parsers as specified |
| // in https://dev.w3.org/html5/html-sourcing-inband-tracks/. |
| std::string kind_; |
| std::string label_; |
| std::string language_; |
| }; |
| |
| // Helper for logging. |
| MEDIA_EXPORT const char* TrackTypeToStr(MediaTrack::Type type); |
| |
| } // namespace media |
| |
| #endif // MEDIA_BASE_MEDIA_TRACK_H_ |