| // Copyright (c) 2012 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. |
| |
| // SourceBufferStream is a data structure that stores media Buffers in ranges. |
| // Buffers can be appended out of presentation order. Buffers are retrieved by |
| // seeking to the desired start point and calling GetNextBuffer(). Buffers are |
| // returned in sequential order to feed decoder, generally near presentation |
| // order though not necessarily the same as presentation order within GOPs of |
| // out-of-order codecs. |
| |
| #ifndef MEDIA_FILTERS_SOURCE_BUFFER_STREAM_H_ |
| #define MEDIA_FILTERS_SOURCE_BUFFER_STREAM_H_ |
| |
| #include <stddef.h> |
| |
| #include <list> |
| #include <memory> |
| #include <string> |
| #include <type_traits> |
| #include <utility> |
| #include <vector> |
| |
| #include "base/macros.h" |
| #include "base/memory/memory_pressure_listener.h" |
| #include "base/memory/ref_counted.h" |
| #include "media/base/audio_decoder_config.h" |
| #include "media/base/media_export.h" |
| #include "media/base/media_log.h" |
| #include "media/base/ranges.h" |
| #include "media/base/stream_parser_buffer.h" |
| #include "media/base/text_track_config.h" |
| #include "media/base/video_decoder_config.h" |
| #include "media/filters/source_buffer_range.h" |
| |
| namespace media { |
| |
| // Status returned by GetNextBuffer(). |
| // kSuccess: Indicates that the next buffer was returned. |
| // kNeedBuffer: Indicates that we need more data before a buffer can be |
| // returned. |
| // kConfigChange: Indicates that the next buffer requires a config change. |
| enum class SourceBufferStreamStatus { |
| kSuccess, |
| kNeedBuffer, |
| kConfigChange, |
| kEndOfStream |
| }; |
| |
| enum class SourceBufferStreamType { kAudio, kVideo, kText }; |
| |
| // See file-level comment for complete description. |
| class MEDIA_EXPORT SourceBufferStream { |
| public: |
| using BufferQueue = StreamParser::BufferQueue; |
| using RangeList = std::list<std::unique_ptr<SourceBufferRange>>; |
| |
| // Helper for PrepareRangesForNextAppend and BufferQueueToLogString that |
| // populates |start| and |end| with the presentation interval of |buffers|. |
| static void GetTimestampInterval(const BufferQueue& buffers, |
| base::TimeDelta* start, |
| base::TimeDelta* end); |
| |
| #if defined(STARBOARD) |
| SourceBufferStream(const std::string& mime_type, |
| const AudioDecoderConfig& audio_config, |
| MediaLog* media_log); |
| SourceBufferStream(const std::string& mime_type, |
| const VideoDecoderConfig& video_config, |
| MediaLog* media_log); |
| #else // defined (STARBOARD) |
| SourceBufferStream(const AudioDecoderConfig& audio_config, |
| MediaLog* media_log); |
| SourceBufferStream(const VideoDecoderConfig& video_config, |
| MediaLog* media_log); |
| #endif // defined (STARBOARD) |
| |
| SourceBufferStream(const TextTrackConfig& text_config, MediaLog* media_log); |
| |
| SourceBufferStream(const SourceBufferStream&) = delete; |
| SourceBufferStream& operator=(const SourceBufferStream&) = delete; |
| |
| ~SourceBufferStream(); |
| |
| // Signals that the next buffers appended are part of a new coded frame group |
| // starting at |coded_frame_group_start_pts|. |
| void OnStartOfCodedFrameGroup(base::TimeDelta coded_frame_group_start_pts); |
| |
| // Add the |buffers| to the SourceBufferStream. Buffers within the queue are |
| // expected to be in order, but multiple calls to Append() may add buffers out |
| // of order or overlapping. Assumes all buffers within |buffers| are in |
| // presentation order and are non-overlapping. |
| void Append(const BufferQueue& buffers); |
| |
| // Removes buffers between |start| and |end| according to the steps |
| // in the "Coded Frame Removal Algorithm" in the Media Source |
| // Extensions Spec. |
| // https://dvcs.w3.org/hg/html-media/raw-file/default/media-source/media-source.html#sourcebuffer-coded-frame-removal |
| // |
| // |duration| is the current duration of the presentation. It is |
| // required by the computation outlined in the spec. |
| void Remove(base::TimeDelta start, base::TimeDelta end, |
| base::TimeDelta duration); |
| |
| // Frees up space if the SourceBufferStream is taking up too much memory. |
| // |media_time| is current playback position. |
| bool GarbageCollectIfNeeded(base::TimeDelta media_time, size_t newDataSize); |
| |
| // Gets invoked when the system is experiencing memory pressure, i.e. there's |
| // not enough free memory. The |media_time| is the media playback position at |
| // the time of memory pressure notification (needed for accurate GC). The |
| // |memory_pressure_level| indicates memory pressure severity. The |
| // |force_instant_gc| is used to force the MSE garbage collection algorithm to |
| // be run right away, without waiting for the next append. |
| void OnMemoryPressure( |
| base::TimeDelta media_time, |
| base::MemoryPressureListener::MemoryPressureLevel memory_pressure_level, |
| bool force_instant_gc); |
| |
| // Changes the SourceBufferStream's state so that it will start returning |
| // buffers starting from the closest keyframe before |timestamp|. |
| void Seek(base::TimeDelta timestamp); |
| |
| // Returns true if the SourceBufferStream has seeked to a time without |
| // buffered data and is waiting for more data to be appended. |
| bool IsSeekPending() const; |
| |
| // Notifies the SourceBufferStream that the media duration has been changed to |
| // |duration| so it should drop any data past that point. |
| void OnSetDuration(base::TimeDelta duration); |
| |
| // Fills |out_buffer| with a new buffer. Buffers are presented in order from |
| // the last call to Seek(), or starting with the first buffer appended if |
| // Seek() has not been called yet. |
| // |out_buffer|'s timestamp may be earlier than the |timestamp| passed to |
| // the last Seek() call. |
| // Returns kSuccess if |out_buffer| is filled with a valid buffer, kNeedBuffer |
| // if there is not enough data buffered to fulfill the request, and |
| // kConfigChange if the next buffer requires a config change. |
| SourceBufferStreamStatus GetNextBuffer( |
| scoped_refptr<StreamParserBuffer>* out_buffer); |
| |
| // Returns a list of the buffered time ranges. |
| Ranges<base::TimeDelta> GetBufferedTime() const; |
| |
| // Returns the highest buffered PTS or base::TimeDelta() if nothing is |
| // buffered. |
| base::TimeDelta GetHighestPresentationTimestamp() const; |
| |
| // Returns the duration of the buffered ranges, which is equivalent |
| // to the end timestamp of the last buffered range. If no data is buffered |
| // then base::TimeDelta() is returned. |
| base::TimeDelta GetBufferedDuration() const; |
| |
| // Returns the size of the buffered data in bytes. |
| size_t GetBufferedSize() const; |
| |
| // Notifies this object that end of stream has been signalled. |
| void MarkEndOfStream(); |
| |
| // Clear the end of stream state set by MarkEndOfStream(). |
| void UnmarkEndOfStream(); |
| |
| const AudioDecoderConfig& GetCurrentAudioDecoderConfig(); |
| const VideoDecoderConfig& GetCurrentVideoDecoderConfig(); |
| const TextTrackConfig& GetCurrentTextTrackConfig(); |
| |
| // Notifies this object that the audio config has changed and buffers in |
| // future Append() calls should be associated with this new config. |
| // If the codec is allowed to change, the caller should set |
| // |allow_codec_change| to true. |
| bool UpdateAudioConfig(const AudioDecoderConfig& config, |
| bool allow_codec_change); |
| |
| // Notifies this object that the video config has changed and buffers in |
| // future Append() calls should be associated with this new config. |
| // If the codec is allowed to change, the caller should set |
| // |allow_codec_change| to true. |
| bool UpdateVideoConfig(const VideoDecoderConfig& config, |
| bool allow_codec_change); |
| |
| // Returns the largest distance between two adjacent buffers in this stream, |
| // or an estimate if no two adjacent buffers have been appended to the stream |
| // yet. |
| base::TimeDelta GetMaxInterbufferDistance() const; |
| |
| void set_memory_limit(size_t memory_limit) { |
| memory_limit_ = memory_limit; |
| } |
| |
| private: |
| friend class SourceBufferStreamTest; |
| |
| // Attempts to delete approximately |total_bytes_to_free| amount of data |
| // |ranges_|, starting at the front of |ranges_| and moving linearly forward |
| // through the buffers. Deletes starting from the back if |reverse_direction| |
| // is true. |media_time| is current playback position. |
| // Returns the number of bytes freed. |
| size_t FreeBuffers(size_t total_bytes_to_free, |
| base::TimeDelta media_time, |
| bool reverse_direction); |
| |
| // Attempts to delete approximately |total_bytes_to_free| amount of data from |
| // |ranges_|, starting after the last appended media |
| // (|highest_buffered_end_time_in_append_sequence_|) but before the current |
| // playback position |media_time|. |
| size_t FreeBuffersAfterLastAppended(size_t total_bytes_to_free, |
| base::TimeDelta media_time); |
| |
| // Gets the removal range to secure |total_bytes_to_free| from |
| // [|start_timestamp|, |end_timestamp|). |
| // Returns the size of buffers to secure if future |
| // Remove(|start_timestamp|, |removal_end_timestamp|, duration) is called. |
| // Will not update |removal_end_timestamp| if the returned size is 0. |
| size_t GetRemovalRange(base::TimeDelta start_timestamp, |
| base::TimeDelta end_timestamp, |
| size_t total_bytes_to_free, |
| base::TimeDelta* removal_end_timestamp); |
| |
| // Prepares |range_for_next_append_| so |new_buffers| can be appended. |
| // This involves removing buffers between the end of the previous append |
| // and any buffers covered by the time range in |new_buffers|. |
| // |deleted_buffers| is an output parameter containing candidates for |
| // |track_buffer_| if this method ends up removing the current playback |
| // position from the range. |
| void PrepareRangesForNextAppend(const BufferQueue& new_buffers, |
| BufferQueue* deleted_buffers); |
| |
| // Removes buffers, from the |track_buffer_|, that come after |timestamp|. |
| // Due to out-of-order decode versus presentation times for some kinds of |
| // media, |timestamp| should be the time of a keyframe known by the caller. |
| // |timestamp| must not be kNoTimestamp. |
| void PruneTrackBuffer(const base::TimeDelta timestamp); |
| |
| // Checks to see if |range_with_new_buffers_itr| can be merged with the range |
| // next to it, and merges them if so while preserving correctness of |
| // |range_for_next_append_| and |selected_range_|. |
| void MergeWithNextRangeIfNecessary( |
| const RangeList::iterator& range_with_new_buffers_itr); |
| |
| // Merges any adjacent ranges while preserving correctness of |
| // |range_for_next_append_| and |selected_range_|. |
| void MergeAllAdjacentRanges(); |
| |
| // Returns true if |next_gop_timestamp| follows |
| // |highest_timestamp_in_append_sequence_| within fudge room. |
| bool IsNextGopAdjacentToEndOfCurrentAppendSequence( |
| base::TimeDelta next_gop_timestamp) const; |
| |
| // Helper method that returns the timestamp for the next buffer that |
| // |selected_range_| will return from GetNextBuffer() call, or kNoTimestamp |
| // if in between seeking (i.e. |selected_range_| is null). |
| base::TimeDelta GetNextBufferTimestamp(); |
| |
| // Finds the range that should contain a coded frame group that begins with |
| // |start_timestamp| (presentation time) and returns the iterator pointing to |
| // it. Returns |ranges_.end()| if there's no such existing range. |
| RangeList::iterator FindExistingRangeFor(base::TimeDelta start_timestamp); |
| |
| // Inserts |new_range| into |ranges_| preserving sorted order. Returns an |
| // iterator in |ranges_| that points to |new_range|. |new_range| becomes owned |
| // by |ranges_|. |
| RangeList::iterator AddToRanges(std::unique_ptr<SourceBufferRange> new_range); |
| |
| // Sets the |selected_range_| to |range| and resets the next buffer position |
| // for the previous |selected_range_|. |
| void SetSelectedRange(SourceBufferRange* range); |
| |
| // Seeks |range| to |seek_timestamp| and then calls SetSelectedRange() with |
| // |range|. |
| void SeekAndSetSelectedRange(SourceBufferRange* range, |
| base::TimeDelta seek_timestamp); |
| |
| // Resets this stream back to an unseeked state. |
| void ResetSeekState(); |
| |
| // Reset state tracking various metadata about the last appended buffer. |
| void ResetLastAppendedState(); |
| |
| // Returns true if |seek_timestamp| refers to the beginning of the first range |
| // in |ranges_|, false otherwise or if |ranges_| is empty. |
| bool ShouldSeekToStartOfBuffered(base::TimeDelta seek_timestamp) const; |
| |
| // Returns true if the decode timestamps of |buffers| are monotonically |
| // increasing (within each GOP) since the previous append to the coded frame |
| // group, false otherwise. |
| bool IsDtsMonotonicallyIncreasing(const BufferQueue& buffers); |
| |
| // Returns true if |selected_range_| is the only range in |ranges_| that |
| // HasNextBufferPosition(). |
| bool OnlySelectedRangeIsSeeked() const; |
| |
| // Measures the distances between buffer decode timestamps and tracks the max. |
| // This enables a reasonable approximation of adjacency fudge room, even for |
| // out-of-order PTS vs DTS sequences. Returns true if |
| // |max_interbuffer_distance_| was changed. |
| bool UpdateMaxInterbufferDtsDistance(const BufferQueue& buffers); |
| |
| // Sets the config ID for each buffer to |append_config_index_|. |
| void SetConfigIds(const BufferQueue& buffers); |
| |
| // Called to complete a config change. Updates |current_config_index_| to |
| // match the index of the next buffer. Calling this method causes |
| // GetNextBuffer() to stop returning kConfigChange and start returning |
| // kSuccess. |
| void CompleteConfigChange(); |
| |
| // Sets |selected_range_| and seeks to the nearest keyframe after |
| // |timestamp| if necessary and possible. This method only attempts to |
| // set |selected_range_| if |seleted_range_| is null and |track_buffer_| |
| // is empty. |
| void SetSelectedRangeIfNeeded(const base::TimeDelta timestamp); |
| |
| // Find a keyframe timestamp that is >= |start_timestamp| and can be used to |
| // find a new selected range. |
| // Returns kNoTimestamp if an appropriate keyframe timestamp could not be |
| // found. |
| base::TimeDelta FindNewSelectedRangeSeekTimestamp( |
| const base::TimeDelta start_timestamp); |
| |
| // Searches |ranges_| for the first keyframe timestamp that is >= |timestamp|. |
| // If |ranges_| doesn't contain a GOP that covers |timestamp| or doesn't |
| // have a keyframe after |timestamp| then kNoTimestamp is returned. |
| base::TimeDelta FindKeyframeAfterTimestamp(const base::TimeDelta timestamp); |
| |
| // Returns "VIDEO" for a video SourceBufferStream, "AUDIO" for an audio |
| // stream, and "TEXT" for a text stream. |
| std::string GetStreamTypeName() const; |
| |
| // (Audio only) If |new_buffers| overlap existing buffers, trims end of |
| // existing buffers to remove overlap. |new_buffers| are not modified. |
| void TrimSpliceOverlap(const BufferQueue& new_buffers); |
| |
| // Returns true if end of stream has been reached, i.e. the |
| // following conditions are met: |
| // 1. end of stream is marked and there is nothing in the track_buffer. |
| // 2. We don't have any ranges, or the last or no range is selected, |
| // or there is a pending seek beyond any existing ranges. |
| bool IsEndOfStreamReached() const; |
| |
| // Deletes the range pointed to by |*itr| and removes it from |ranges_|. |
| // If |*itr| points to |selected_range_|, then |selected_range_| is set to |
| // NULL. After the range is removed, |*itr| is to the range after the one that |
| // was removed or to |ranges_.end()| if the last range was removed. |
| void DeleteAndRemoveRange(RangeList::iterator* itr); |
| |
| // Helper function used when updating |range_for_next_append_|. Returns a |
| // guess of what the next append timestamp will be based on |
| // |last_appended_buffer_timestamp_|, |new_coded_frame_group_| and |
| // |coded_frame_group_start_pts_|. Returns kNoTimestamp if unable to guess, |
| // which can occur prior to first OnStartOfCodedFrameGroup(), or when the most |
| // recent GOP appended to since the last OnStartOfCodedFrameGroup() is |
| // removed. |
| base::TimeDelta PotentialNextAppendTimestamp() const; |
| |
| // Helper function used by Remove() and PrepareRangesForNextAppend() to |
| // remove buffers and ranges between |start| and |end|. |
| // |exclude_start| - If set to true, buffers with timestamps that |
| // match |start| are not removed. If set to false, buffers with |
| // timestamps that match |start| will be removed. |
| // |*deleted_buffers| - Filled with buffers for the current playback position |
| // if the removal range included the current playback position. These buffers |
| // can be used as candidates for placing in the |track_buffer_|. |
| void RemoveInternal(base::TimeDelta start, |
| base::TimeDelta end, |
| bool exclude_start, |
| BufferQueue* deleted_buffers); |
| |
| // Helper function used by RemoveInternal() to evaluate whether remove will |
| // disrupt the last appended GOP. If disruption is expected, reset state |
| // tracking the last append. This will trigger frame filtering in Append() |
| // until a new key frame is provided. |
| void UpdateLastAppendStateForRemove(base::TimeDelta remove_start, |
| base::TimeDelta remove_end, |
| bool exclude_start); |
| |
| SourceBufferStreamType GetType() const; |
| |
| // See GetNextBuffer() for additional details. This method handles preroll |
| // frame processing. |
| SourceBufferStreamStatus HandleNextBufferWithPreroll( |
| scoped_refptr<StreamParserBuffer>* out_buffer); |
| |
| // See GetNextBuffer() for additional details. The internal method hands out |
| // single buffers from the |track_buffer_| and |selected_range_| without |
| // additional processing for preroll buffers. |
| SourceBufferStreamStatus GetNextBufferInternal( |
| scoped_refptr<StreamParserBuffer>* out_buffer); |
| |
| // If the next buffer's timestamp is significantly beyond the last output |
| // buffer, and if we just exhausted |track_buffer_| on the previous read, this |
| // method logs a warning to |media_log_| that there could be perceivable |
| // delay. Apps can avoid this behavior by not overlap-appending buffers near |
| // current playback position. |
| void WarnIfTrackBufferExhaustionSkipsForward( |
| scoped_refptr<StreamParserBuffer> next_buffer); |
| |
| // If |out_buffer| has preroll, sets |pending_buffer_| to feed out preroll and |
| // returns true. Otherwise returns false. |
| bool SetPendingBuffer(scoped_refptr<StreamParserBuffer>* out_buffer); |
| |
| #if defined(STARBOARD) |
| // Returns the accumulated duration of all ranges. This is solely used by |
| // duration base garbage collection. |
| base::TimeDelta GetBufferedDurationForGarbageCollection() const; |
| |
| const std::string mime_type_; |
| #endif // defined (STARBOARD) |
| |
| // Used to report log messages that can help the web developer figure out what |
| // is wrong with the content. |
| MediaLog* media_log_; |
| |
| // List of disjoint buffered ranges, ordered by start time. |
| RangeList ranges_; |
| |
| // Indicates which decoder config is being used by the decoder. |
| // GetNextBuffer() is only allows to return buffers that have a |
| // config ID that matches this index. If there is a mismatch then |
| // it must signal that a config change is needed. |
| int current_config_index_ = 0; |
| |
| // Indicates which decoder config to associate with new buffers |
| // being appended. Each new buffer appended has its config ID set |
| // to the value of this field. |
| int append_config_index_ = 0; |
| |
| // Holds the audio/video configs for this stream. |current_config_index_| |
| // and |append_config_index_| represent indexes into one of these vectors. |
| std::vector<AudioDecoderConfig> audio_configs_; |
| std::vector<VideoDecoderConfig> video_configs_; |
| |
| // Holds the text config for this stream. |
| TextTrackConfig text_track_config_; |
| |
| // True if more data needs to be appended before the Seek() can complete, |
| // false if no Seek() has been requested or the Seek() is completed. |
| bool seek_pending_ = false; |
| |
| // True if the end of the stream has been signalled. |
| bool end_of_stream_ = false; |
| |
| // Timestamp of the last request to Seek(). |
| base::TimeDelta seek_buffer_timestamp_; |
| |
| // Pointer to the seeked-to Range. This is the range from which |
| // GetNextBuffer() calls are fulfilled after the |track_buffer_| has been |
| // emptied. |
| SourceBufferRange* selected_range_ = nullptr; |
| |
| // Queue of the next buffers to be returned from calls to GetNextBuffer(). If |
| // |track_buffer_| is empty, return buffers from |selected_range_|. |
| BufferQueue track_buffer_; |
| |
| // If there has been no intervening Seek, this will be true if the last |
| // emitted buffer emptied |track_buffer_|. |
| bool just_exhausted_track_buffer_ = false; |
| |
| // The start presentation time of the current coded frame group being |
| // appended. |
| base::TimeDelta coded_frame_group_start_pts_; |
| |
| // Points to the range containing the current coded frame group being |
| // appended. |
| RangeList::iterator range_for_next_append_; |
| |
| // True when the next call to Append() begins a new coded frame group. |
| // TODO(wolenetz): Simplify by passing this flag into Append(). |
| bool new_coded_frame_group_ = false; |
| |
| // The timestamp of the last buffer appended to the coded frame group, set to |
| // kNoTimestamp if the beginning of the group. |
| base::TimeDelta last_appended_buffer_timestamp_ = kNoTimestamp; |
| base::TimeDelta last_appended_buffer_duration_ = kNoTimestamp; |
| bool last_appended_buffer_is_keyframe_ = false; |
| |
| // When buffering GOPs by keyframe PTS and intra-gop by nonkeyframe DTS, to |
| // verify monotonically increasing intra-GOP DTS sequence and to update max |
| // interbuffer distance also by DTS deltas within a coded frame group, the |
| // following is needed. |
| DecodeTimestamp last_appended_buffer_decode_timestamp_ = kNoDecodeTimestamp(); |
| |
| // The following is the highest presentation timestamp appended so far in this |
| // coded frame group. Due to potentially out-of-order decode versus |
| // presentation time sequence, this isn't necessarily the most recently |
| // appended frame. This is used as the lower bound of removing previously |
| // buffered media when processing new appends. |
| base::TimeDelta highest_timestamp_in_append_sequence_ = kNoTimestamp; |
| |
| // The following is used in determining if FreeBuffersAfterLastAppended() is |
| // allowed during garbage collection. Due to out-of-order decode versus |
| // presentation sequence, this isn't necessarily the end time of the most |
| // recently appended frame. |
| base::TimeDelta highest_buffered_end_time_in_append_sequence_ = kNoTimestamp; |
| |
| // The highest presentation timestamp for buffers returned by recent |
| // GetNextBuffer() calls. Set to kNoTimestamp if GetNextBuffer() hasn't been |
| // called yet or a seek has happened since the last GetNextBuffer() call. |
| base::TimeDelta highest_output_buffer_timestamp_; |
| |
| // Stores the largest distance between two adjacent buffers in this stream. |
| base::TimeDelta max_interbuffer_distance_; |
| |
| base::MemoryPressureListener::MemoryPressureLevel memory_pressure_level_ = |
| base::MemoryPressureListener::MEMORY_PRESSURE_LEVEL_NONE; |
| |
| // The maximum amount of data in bytes the stream will keep in memory. |
| // |memory_limit_| is initialized based on the audio/video configuration in |
| // the constructor, but either user-setting of |memory_limit_| or |
| // memory-pressure-based adjustment to determine effective limit in the |
| // eviction heuristic can cause the result to vary from the value set in |
| // constructor. |
| size_t memory_limit_; |
| |
| // Indicates that a kConfigChanged status has been reported by GetNextBuffer() |
| // and GetCurrentXXXDecoderConfig() must be called to update the current |
| // config. GetNextBuffer() must not be called again until |
| // GetCurrentXXXDecoderConfig() has been called. |
| bool config_change_pending_ = false; |
| |
| // Used by HandleNextBufferWithPreroll() when a buffer with preroll is |
| // returned from GetNextBufferInternal(). |
| scoped_refptr<StreamParserBuffer> pending_buffer_; |
| |
| // Indicates that all buffers before |pending_buffer_| have been handed out. |
| bool pending_buffers_complete_ = false; |
| |
| // To prevent log spam, count the number of logs for different log scenarios. |
| int num_splice_logs_ = 0; |
| int num_track_buffer_gap_warning_logs_ = 0; |
| int num_garbage_collect_algorithm_logs_ = 0; |
| }; |
| |
| } // namespace media |
| |
| #endif // MEDIA_FILTERS_SOURCE_BUFFER_STREAM_H_ |