Add config change handling to SourceBufferStream & ChunkDemuxer

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.
 
 #ifndef MEDIA_FILTERS_SOURCE_BUFFER_STREAM_H_
 #define MEDIA_FILTERS_SOURCE_BUFFER_STREAM_H_
 
 #include <deque>
 #include <list>
 #include <utility>
+#include <vector>
 
 #include "base/memory/ref_counted.h"
 #include "media/base/audio_decoder_config.h"
 #include "media/base/media_export.h"
 #include "media/base/ranges.h"
 #include "media/base/stream_parser_buffer.h"
 #include "media/base/video_decoder_config.h"
 
 namespace media {
 
 class SourceBufferRange;
 
 // 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.
 class MEDIA_EXPORT SourceBufferStream {
  public:
   typedef std::deque<scoped_refptr<StreamParserBuffer> > BufferQueue;
 
+  // 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 Status {
+    kSuccess,
+    kNeedBuffer,
+    kConfigChange,
+  };
+
   explicit SourceBufferStream(const AudioDecoderConfig& audio_config);
   explicit SourceBufferStream(const VideoDecoderConfig& video_config);
 
   ~SourceBufferStream();
 
   // Signals that the next buffers appended are part of a new media segment
   // starting at |media_segment_start_time|.
   void OnNewMediaSegment(base::TimeDelta media_segment_start_time);
 
   // Add the |buffers| to the SourceBufferStream. Buffers within the queue are
@@ skipping 10 matching lines @@
 
   // 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;
 
   // 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 true if |out_buffer| is filled with a valid buffer, false if
-  // there is not enough data buffered to fulfill the request.
-  bool GetNextBuffer(scoped_refptr<StreamParserBuffer>* out_buffer);
+  // 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.
+  Status GetNextBuffer(scoped_refptr<StreamParserBuffer>* out_buffer);
 
   // Returns a list of the buffered time ranges.
   Ranges<base::TimeDelta> GetBufferedTime() const;
 
   // Notifies this SourceBufferStream that EndOfStream has been called and that
   // GetNextBuffer() should return EOS buffers after all other buffered data.
   // Returns false if called when there is a gap between the current position
   // and the end of the buffered data.
   void EndOfStream();
 
   // Returns true if this SourceBufferStream can successfully call EndOfStream()
   // (if there are no gaps between the current position and the remaining data).
   bool CanEndOfStream() const;
 
   const AudioDecoderConfig& GetCurrentAudioDecoderConfig() {
-    return audio_config_;
+    return *audio_configs_[current_config_index_];
   }
   const VideoDecoderConfig& GetCurrentVideoDecoderConfig() {
-    return video_config_;
+    return *video_configs_[current_config_index_];
   }
 
+  // Notifies this object that the audio config has changed and buffers in
+  // future Append() calls should be associated with this new config.
+  bool UpdateAudioConfig(const AudioDecoderConfig& config);
+
+  // Notifies this object that the video config has changed and buffers in
+  // future Append() calls should be associated with this new config.
+  bool UpdateVideoConfig(const VideoDecoderConfig& config);
+
+  // 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 UpdateCurrentConfigIndex();
+
   // 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;
 
  private:
   typedef std::list<SourceBufferRange*> RangeList;
 
   // Appends |new_buffers| into |range_for_new_buffers_itr|, handling start and
   // end overlaps if necessary.
@@ skipping 60 matching lines @@
   // |selected_range_| lives.
   RangeList::iterator GetSelectedRangeItr();
 
   // Returns true if the timestamps of |buffers| are monotonically increasing
   // since the previous append to the media segment, false otherwise.
   bool IsMonotonicallyIncreasing(const BufferQueue& buffers);
 
   // Measures the distances between buffer timestamps and tracks the max.
   void UpdateMaxInterbufferDistance(const BufferQueue& buffers);
 
+  // Calls set_config_id() on each buffer with |append_config_index_|.

[vrk (LEFT CHROMIUM), 2012/07/12 19:37:55]

nit: Since the "set_config_id()" method isn't in this class, maybe say something
more general like "Sets the config id for each buffer to
|append_config_index_|."

[acolwell GONE FROM CHROMIUM, 2012/07/12 23:07:58]

Done.

+  void SetConfigIDs(const BufferQueue& buffers);

[xhwang, 2012/07/12 18:09:12]

s/ID/Id?

[acolwell GONE FROM CHROMIUM, 2012/07/12 23:07:58]

Done.

+
   // List of disjoint buffered ranges, ordered by start time.
   RangeList ranges_;
 
-  AudioDecoderConfig audio_config_;
-  VideoDecoderConfig video_config_;
+  int current_config_index_;

[vrk (LEFT CHROMIUM), 2012/07/12 19:37:55]

nit: add comments for new fields

[acolwell GONE FROM CHROMIUM, 2012/07/12 23:07:58]

Done.

+  int append_config_index_;
+  std::vector<AudioDecoderConfig*> audio_configs_;
+  std::vector<VideoDecoderConfig*> video_configs_;
 
   // 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_;
 
   // 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
@@ skipping 23 matching lines @@
 
   // Stores the largest distance between two adjacent buffers in this stream.
   base::TimeDelta max_interbuffer_distance_;
 
   DISALLOW_COPY_AND_ASSIGN(SourceBufferStream);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_SOURCE_BUFFER_STREAM_H_