MediaCodecPlayer implementation (stage 5 - reconfiguration)

media/base/android/access_unit_queue.h

 // Copyright 2015 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_ANDROID_ACCESS_UNIT_QUEUE_H_
 #define MEDIA_BASE_ANDROID_ACCESS_UNIT_QUEUE_H_
 
 #include <list>
 
 #include "base/macros.h"
@@ skipping 52 matching lines @@
   // the look-back is inclusive of the current front position).
   // If the key frame exists, sets the current access unit to it and returns
   // true. Otherwise returns false.
   bool RewindToLastKeyFrame();
 
   // Returns the information about the queue.
   // The result is invalidated by the following Advance() or Flush call.
   // There must be only one |Info| consumer at a time.
   Info GetInfo() const;
 
+  // Request to emulate config changes for some key frames.

[qinmin, 2015/08/20 19:41:25]

I don't understand this. Why is this function needed? what is the usecase?

+  void EmulateConfigChanges(bool value);
+  void SetLastConfigs(const DemuxerConfigs& configs);
+
   // For unit tests only. These methods are not thread safe.
   size_t NumChunksForTesting() const { return chunks_.size(); }
   void SetHistorySizeForTesting(size_t number_of_history_chunks);
 
  private:
   // Returns the amount of access units between the current one and the end,
   // incuding current. Logically these are units that have not been consumed.
   int GetUnconsumedAccessUnitLength() const;
 
+  // Clone and possibly split (when we emulate configs) the incoming data chunk.
+  std::vector<DemuxerData*> CloneData(const DemuxerData& data);
+
   // The queue of data chunks. It owns the chunks.
   typedef std::list<DemuxerData*> DataChunkQueue;
   DataChunkQueue chunks_;
 
   // The chunk that contains the current access unit.
   DataChunkQueue::iterator current_chunk_;
 
   // Index of the current access unit within the current chunk.
   size_t index_in_chunk_;
 
   // Amount of chunks before the |current_chunk_| that's kept for history.
   size_t history_chunks_amount_;
 
   // Indicates that a unit with End Of Stream flag has been appended.
   bool has_eos_;
 
+  // Flag to generate artificial |kConfigChanged| for some key frames.
+  bool emulate_config_changes_;
+
+  // Last config change for emulation
+  DemuxerConfigs last_configs_;
+
   // The lock protects all fields together.
   mutable base::Lock lock_;
 
   DISALLOW_COPY_AND_ASSIGN(AccessUnitQueue);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_ANDROID_ACCESS_UNIT_QUEUE_H_