MSE: Relax the 'media segment must begin with keyframe' requirement

media/filters/source_buffer_stream.h

 // 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 presentation order.
 
 #ifndef MEDIA_FILTERS_SOURCE_BUFFER_STREAM_H_
@@ skipping 50 matching lines @@
                      bool splice_frames_enabled);
   SourceBufferStream(const VideoDecoderConfig& video_config,
                      const scoped_refptr<MediaLog>& media_log,
                      bool splice_frames_enabled);
   SourceBufferStream(const TextTrackConfig& text_config,
                      const scoped_refptr<MediaLog>& media_log,
                      bool splice_frames_enabled);
 
   ~SourceBufferStream();
 
-  // Signals that the next buffers appended are part of a new media segment
-  // starting at |media_segment_start_time|.
+  // Signals that the next buffers appended are part of a new coded frame group
+  // starting at |coded_frame_group_start_time|.
   // TODO(acolwell/wolenetz): This should be changed to a presentation
   // timestamp. See http://crbug.com/402502
-  void OnNewMediaSegment(DecodeTimestamp media_segment_start_time);
+  void OnStartOfCodedFrameGroup(DecodeTimestamp coded_frame_group_start_time);
 
   // 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.
   // Returns true if Append() was successful, false if |buffers| are not added.
   // TODO(vrk): Implement garbage collection. (crbug.com/125070)
   bool Append(const BufferQueue& buffers);
 
   // Removes buffers between |start| and |end| according to the steps
@@ skipping 304 matching lines @@
   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 time of the current media segment being appended.
-  DecodeTimestamp media_segment_start_time_;
+  // The start time of the current coded frame group being appended.
+  DecodeTimestamp coded_frame_group_start_time_;
 
   // Points to the range containing the current media segment being appended.
   RangeList::iterator range_for_next_append_;
 
-  // True when the next call to Append() begins a new media segment.
-  bool new_media_segment_ = false;
+  // 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 media segment, set to
   // kNoDecodeTimestamp() if the beginning of the segment.
   DecodeTimestamp last_appended_buffer_timestamp_ = kNoDecodeTimestamp();
   base::TimeDelta last_appended_buffer_duration_ = kNoTimestamp();
   bool last_appended_buffer_is_keyframe_ = false;
 
   // The decode timestamp on the last buffer returned by the most recent
   // GetNextBuffer() call. Set to kNoDecodeTimestamp() if GetNextBuffer() hasn't
   // been called yet or a seek has happened since the last GetNextBuffer() call.
@@ skipping 31 matching lines @@
   int num_splice_generation_success_logs_ = 0;
   int num_track_buffer_gap_warning_logs_ = 0;
   int num_garbage_collect_algorithm_logs_ = 0;
 
   DISALLOW_COPY_AND_ASSIGN(SourceBufferStream);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_SOURCE_BUFFER_STREAM_H_