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_FILTERS_CHUNK_DEMUXER_H_ 6 #define MEDIA_FILTERS_CHUNK_DEMUXER_H_ 7 8 #include <deque> 9 #include <map> 10 #include <string> 11 #include <utility> 12 #include <vector> 13 14 #include "base/synchronization/lock.h" 15 #include "media/base/byte_queue.h" 16 #include "media/base/demuxer.h" 17 #include "media/base/ranges.h" 18 #include "media/base/stream_parser.h" 19 #include "media/filters/source_buffer_stream.h" 20 21 namespace media { 22 23 class FFmpegURLProtocol; 24 class SourceState; 25 26 class MEDIA_EXPORT ChunkDemuxerStream : public DemuxerStream { 27 public: 28 typedef std::deque<scoped_refptr<StreamParserBuffer> > BufferQueue; 29 30 explicit ChunkDemuxerStream(Type type, bool splice_frames_enabled); 31 virtual ~ChunkDemuxerStream(); 32 33 // ChunkDemuxerStream control methods. 34 void StartReturningData(); 35 void AbortReads(); 36 void CompletePendingReadIfPossible(); 37 void Shutdown(); 38 39 // SourceBufferStream manipulation methods. 40 void Seek(base::TimeDelta time); 41 bool IsSeekWaitingForData() const; 42 43 // Add buffers to this stream. Buffers are stored in SourceBufferStreams, 44 // which handle ordering and overlap resolution. 45 // Returns true if buffers were successfully added. 46 bool Append(const StreamParser::BufferQueue& buffers); 47 48 // Removes buffers between |start| and |end| according to the steps 49 // in the "Coded Frame Removal Algorithm" in the Media Source 50 // Extensions Spec. 51 // https://dvcs.w3.org/hg/html-media/raw-file/default/media-source/media-source.html#sourcebuffer-coded-frame-removal 52 // 53 // |duration| is the current duration of the presentation. It is 54 // required by the computation outlined in the spec. 55 void Remove(base::TimeDelta start, base::TimeDelta end, 56 base::TimeDelta duration); 57 58 // Signal to the stream that duration has changed to |duration|. 59 void OnSetDuration(base::TimeDelta duration); 60 61 // Returns the range of buffered data in this stream, capped at |duration|. 62 Ranges<base::TimeDelta> GetBufferedRanges(base::TimeDelta duration) const; 63 64 // Returns the duration of the buffered data. 65 // Returns base::TimeDelta() if the stream has no buffered data. 66 base::TimeDelta GetBufferedDuration() const; 67 68 // Signal to the stream that buffers handed in through subsequent calls to 69 // Append() belong to a media segment that starts at |start_timestamp|. 70 void OnNewMediaSegment(base::TimeDelta start_timestamp); 71 72 // Called when midstream config updates occur. 73 // Returns true if the new config is accepted. 74 // Returns false if the new config should trigger an error. 75 bool UpdateAudioConfig(const AudioDecoderConfig& config, const LogCB& log_cb); 76 bool UpdateVideoConfig(const VideoDecoderConfig& config, const LogCB& log_cb); 77 void UpdateTextConfig(const TextTrackConfig& config, const LogCB& log_cb); 78 79 void MarkEndOfStream(); 80 void UnmarkEndOfStream(); 81 82 // DemuxerStream methods. 83 virtual void Read(const ReadCB& read_cb) OVERRIDE; 84 virtual Type type() OVERRIDE; 85 virtual void EnableBitstreamConverter() OVERRIDE; 86 virtual AudioDecoderConfig audio_decoder_config() OVERRIDE; 87 virtual VideoDecoderConfig video_decoder_config() OVERRIDE; 88 virtual bool SupportsConfigChanges() OVERRIDE; 89 90 // Returns the text track configuration. It is an error to call this method 91 // if type() != TEXT. 92 TextTrackConfig text_track_config(); 93 94 // Sets the memory limit, in bytes, on the SourceBufferStream. 95 void set_memory_limit_for_testing(int memory_limit) { 96 stream_->set_memory_limit_for_testing(memory_limit); 97 } 98 99 bool supports_partial_append_window_trimming() const { 100 return partial_append_window_trimming_enabled_; 101 } 102 103 private: 104 enum State { 105 UNINITIALIZED, 106 RETURNING_DATA_FOR_READS, 107 RETURNING_ABORT_FOR_READS, 108 SHUTDOWN, 109 }; 110 111 // Assigns |state_| to |state| 112 void ChangeState_Locked(State state); 113 114 void CompletePendingReadIfPossible_Locked(); 115 116 // Specifies the type of the stream. 117 Type type_; 118 119 scoped_ptr<SourceBufferStream> stream_; 120 121 mutable base::Lock lock_; 122 State state_; 123 ReadCB read_cb_; 124 bool splice_frames_enabled_; 125 bool partial_append_window_trimming_enabled_; 126 127 DISALLOW_IMPLICIT_CONSTRUCTORS(ChunkDemuxerStream); 128 }; 129 130 // Demuxer implementation that allows chunks of media data to be passed 131 // from JavaScript to the media stack. 132 class MEDIA_EXPORT ChunkDemuxer : public Demuxer { 133 public: 134 enum Status { 135 kOk, // ID added w/o error. 136 kNotSupported, // Type specified is not supported. 137 kReachedIdLimit, // Reached ID limit. We can't handle any more IDs. 138 }; 139 140 // |open_cb| Run when Initialize() is called to signal that the demuxer 141 // is ready to receive media data via AppenData(). 142 // |need_key_cb| Run when the demuxer determines that an encryption key is 143 // needed to decrypt the content. 144 // |enable_text| Process inband text tracks in the normal way when true, 145 // otherwise ignore them. 146 // |log_cb| Run when parsing error messages need to be logged to the error 147 // console. 148 // |splice_frames_enabled| Indicates that it's okay to generate splice frames 149 // per the MSE specification. Renderers must understand DecoderBuffer's 150 // splice_timestamp() field. 151 ChunkDemuxer(const base::Closure& open_cb, 152 const NeedKeyCB& need_key_cb, 153 const LogCB& log_cb, 154 bool splice_frames_enabled); 155 virtual ~ChunkDemuxer(); 156 157 // Demuxer implementation. 158 virtual void Initialize(DemuxerHost* host, 159 const PipelineStatusCB& cb, 160 bool enable_text_tracks) OVERRIDE; 161 virtual void Stop(const base::Closure& callback) OVERRIDE; 162 virtual void Seek(base::TimeDelta time, const PipelineStatusCB& cb) OVERRIDE; 163 virtual DemuxerStream* GetStream(DemuxerStream::Type type) OVERRIDE; 164 virtual base::TimeDelta GetStartTime() const OVERRIDE; 165 virtual base::Time GetTimelineOffset() const OVERRIDE; 166 virtual Liveness GetLiveness() const OVERRIDE; 167 168 // Methods used by an external object to control this demuxer. 169 // 170 // Indicates that a new Seek() call is on its way. Any pending Reads on the 171 // DemuxerStream objects should be aborted immediately inside this call and 172 // future Read calls should return kAborted until the Seek() call occurs. 173 // This method MUST ALWAYS be called before Seek() is called to signal that 174 // the next Seek() call represents the seek point we actually want to return 175 // data for. 176 // |seek_time| - The presentation timestamp for the seek that triggered this 177 // call. It represents the most recent position the caller is trying to seek 178 // to. 179 void StartWaitingForSeek(base::TimeDelta seek_time); 180 181 // Indicates that a Seek() call is on its way, but another seek has been 182 // requested that will override the impending Seek() call. Any pending Reads 183 // on the DemuxerStream objects should be aborted immediately inside this call 184 // and future Read calls should return kAborted until the next 185 // StartWaitingForSeek() call. This method also arranges for the next Seek() 186 // call received before a StartWaitingForSeek() call to immediately call its 187 // callback without waiting for any data. 188 // |seek_time| - The presentation timestamp for the seek request that 189 // triggered this call. It represents the most recent position the caller is 190 // trying to seek to. 191 void CancelPendingSeek(base::TimeDelta seek_time); 192 193 // Registers a new |id| to use for AppendData() calls. |type| indicates 194 // the MIME type for the data that we intend to append for this ID. 195 // kOk is returned if the demuxer has enough resources to support another ID 196 // and supports the format indicated by |type|. 197 // kNotSupported is returned if |type| is not a supported format. 198 // kReachedIdLimit is returned if the demuxer cannot handle another ID right 199 // now. 200 Status AddId(const std::string& id, const std::string& type, 201 std::vector<std::string>& codecs); 202 203 // Removed an ID & associated resources that were previously added with 204 // AddId(). 205 void RemoveId(const std::string& id); 206 207 // Gets the currently buffered ranges for the specified ID. 208 Ranges<base::TimeDelta> GetBufferedRanges(const std::string& id) const; 209 210 // Appends media data to the source buffer associated with |id|, applying 211 // and possibly updating |*timestamp_offset| during coded frame processing. 212 // |append_window_start| and |append_window_end| correspond to the MSE spec's 213 // similarly named source buffer attributes that are used in coded frame 214 // processing. 215 void AppendData(const std::string& id, const uint8* data, size_t length, 216 base::TimeDelta append_window_start, 217 base::TimeDelta append_window_end, 218 base::TimeDelta* timestamp_offset); 219 220 // Aborts parsing the current segment and reset the parser to a state where 221 // it can accept a new segment. 222 // Some pending frames can be emitted during that process. These frames are 223 // applied |timestamp_offset|. 224 void Abort(const std::string& id, 225 base::TimeDelta append_window_start, 226 base::TimeDelta append_window_end, 227 base::TimeDelta* timestamp_offset); 228 229 // Remove buffers between |start| and |end| for the source buffer 230 // associated with |id|. 231 void Remove(const std::string& id, base::TimeDelta start, 232 base::TimeDelta end); 233 234 // Returns the current presentation duration. 235 double GetDuration(); 236 double GetDuration_Locked(); 237 238 // Notifies the demuxer that the duration of the media has changed to 239 // |duration|. 240 void SetDuration(double duration); 241 242 // Returns true if the source buffer associated with |id| is currently parsing 243 // a media segment, or false otherwise. 244 bool IsParsingMediaSegment(const std::string& id); 245 246 // Set the append mode to be applied to subsequent buffers appended to the 247 // source buffer associated with |id|. If |sequence_mode| is true, caller 248 // is requesting "sequence" mode. Otherwise, caller is requesting "segments" 249 // mode. 250 void SetSequenceMode(const std::string& id, bool sequence_mode); 251 252 // Signals the coded frame processor for the source buffer associated with 253 // |id| to update its group start timestamp to be |timestamp_offset| if it is 254 // in sequence append mode. 255 void SetGroupStartTimestampIfInSequenceMode(const std::string& id, 256 base::TimeDelta timestamp_offset); 257 258 // Called to signal changes in the "end of stream" 259 // state. UnmarkEndOfStream() must not be called if a matching 260 // MarkEndOfStream() has not come before it. 261 void MarkEndOfStream(PipelineStatus status); 262 void UnmarkEndOfStream(); 263 264 void Shutdown(); 265 266 // Sets the memory limit on each stream. |memory_limit| is the 267 // maximum number of bytes each stream is allowed to hold in its buffer. 268 void SetMemoryLimitsForTesting(int memory_limit); 269 270 // Returns the ranges representing the buffered data in the demuxer. 271 // TODO(wolenetz): Remove this method once MediaSourceDelegate no longer 272 // requires it for doing hack browser seeks to I-frame on Android. See 273 // http://crbug.com/304234. 274 Ranges<base::TimeDelta> GetBufferedRanges() const; 275 276 private: 277 enum State { 278 WAITING_FOR_INIT, 279 INITIALIZING, 280 INITIALIZED, 281 ENDED, 282 PARSE_ERROR, 283 SHUTDOWN, 284 }; 285 286 void ChangeState_Locked(State new_state); 287 288 // Reports an error and puts the demuxer in a state where it won't accept more 289 // data. 290 void ReportError_Locked(PipelineStatus error); 291 292 // Returns true if any stream has seeked to a time without buffered data. 293 bool IsSeekWaitingForData_Locked() const; 294 295 // Returns true if all streams can successfully call EndOfStream, 296 // false if any can not. 297 bool CanEndOfStream_Locked() const; 298 299 // SourceState callbacks. 300 void OnSourceInitDone(bool success, 301 const StreamParser::InitParameters& params); 302 303 // Creates a DemuxerStream for the specified |type|. 304 // Returns a new ChunkDemuxerStream instance if a stream of this type 305 // has not been created before. Returns NULL otherwise. 306 ChunkDemuxerStream* CreateDemuxerStream(DemuxerStream::Type type); 307 308 void OnNewTextTrack(ChunkDemuxerStream* text_stream, 309 const TextTrackConfig& config); 310 311 // Returns true if |source_id| is valid, false otherwise. 312 bool IsValidId(const std::string& source_id) const; 313 314 // Increases |duration_| to |new_duration|, if |new_duration| is higher. 315 void IncreaseDurationIfNecessary(base::TimeDelta new_duration); 316 317 // Decreases |duration_| if the buffered region is less than |duration_| when 318 // EndOfStream() is called. 319 void DecreaseDurationIfNecessary(); 320 321 // Sets |duration_| to |new_duration|, sets |user_specified_duration_| to -1 322 // and notifies |host_|. 323 void UpdateDuration(base::TimeDelta new_duration); 324 325 // Returns the ranges representing the buffered data in the demuxer. 326 Ranges<base::TimeDelta> GetBufferedRanges_Locked() const; 327 328 // Start returning data on all DemuxerStreams. 329 void StartReturningData(); 330 331 // Aborts pending reads on all DemuxerStreams. 332 void AbortPendingReads(); 333 334 // Completes any pending reads if it is possible to do so. 335 void CompletePendingReadsIfPossible(); 336 337 // Seeks all SourceBufferStreams to |seek_time|. 338 void SeekAllSources(base::TimeDelta seek_time); 339 340 // Shuts down all DemuxerStreams by calling Shutdown() on 341 // all objects in |source_state_map_|. 342 void ShutdownAllStreams(); 343 344 mutable base::Lock lock_; 345 State state_; 346 bool cancel_next_seek_; 347 348 DemuxerHost* host_; 349 base::Closure open_cb_; 350 NeedKeyCB need_key_cb_; 351 bool enable_text_; 352 // Callback used to report error strings that can help the web developer 353 // figure out what is wrong with the content. 354 LogCB log_cb_; 355 356 PipelineStatusCB init_cb_; 357 // Callback to execute upon seek completion. 358 // TODO(wolenetz/acolwell): Protect against possible double-locking by first 359 // releasing |lock_| before executing this callback. See 360 // http://crbug.com/308226 361 PipelineStatusCB seek_cb_; 362 363 scoped_ptr<ChunkDemuxerStream> audio_; 364 scoped_ptr<ChunkDemuxerStream> video_; 365 366 base::TimeDelta duration_; 367 368 // The duration passed to the last SetDuration(). If 369 // SetDuration() is never called or an AppendData() call or 370 // a EndOfStream() call changes |duration_|, then this 371 // variable is set to < 0 to indicate that the |duration_| represents 372 // the actual duration instead of a user specified value. 373 double user_specified_duration_; 374 375 base::Time timeline_offset_; 376 Liveness liveness_; 377 378 typedef std::map<std::string, SourceState*> SourceStateMap; 379 SourceStateMap source_state_map_; 380 381 // Used to ensure that (1) config data matches the type and codec provided in 382 // AddId(), (2) only 1 audio and 1 video sources are added, and (3) ids may be 383 // removed with RemoveID() but can not be re-added (yet). 384 std::string source_id_audio_; 385 std::string source_id_video_; 386 387 // Indicates that splice frame generation is enabled. 388 const bool splice_frames_enabled_; 389 390 DISALLOW_COPY_AND_ASSIGN(ChunkDemuxer); 391 }; 392 393 } // namespace media 394 395 #endif // MEDIA_FILTERS_CHUNK_DEMUXER_H_ 396