Implemented a proper clock for audio/video synchronization.

media/base/pipeline_impl.h

 // Copyright (c) 2008-2009 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.
 
 // Implementation of Pipeline.
 
 #ifndef MEDIA_BASE_PIPELINE_IMPL_H_
 #define MEDIA_BASE_PIPELINE_IMPL_H_
 
 #include <string>
 #include <vector>
 #include <set>
 
 #include "base/message_loop.h"
 #include "base/ref_counted.h"
 #include "base/thread.h"
 #include "base/time.h"
+#include "media/base/clock_impl.h"
 #include "media/base/filter_host.h"
 #include "media/base/pipeline.h"
 
 namespace media {
 
 
 // PipelineImpl runs the media pipeline.  Filters are created and called on the
 // message loop injected into this object. PipelineImpl works like a state
 // machine to perform asynchronous initialization, pausing, seeking and playing.
 //
@@ skipping 241 matching lines @@
   // Current volume level (from 0.0f to 1.0f).  This value is set immediately
   // via SetVolume() and a task is dispatched on the message loop to notify the
   // filters.
   float volume_;
 
   // Current playback rate (>= 0.0f).  This value is set immediately via
   // SetPlaybackRate() and a task is dispatched on the message loop to notify
   // the filters.
   float playback_rate_;
 
-  // Current playback time.  Set by filters.
-  base::TimeDelta time_;
+  // Reference clock.  Keeps track of current playback time.  Uses system
+  // clock and linear interpolation, but can have its time manually set
+  // by filters.
+  ClockImpl clock_;
 
   // Status of the pipeline.  Initialized to PIPELINE_OK which indicates that
   // the pipeline is operating correctly. Any other value indicates that the
   // pipeline is stopped or is stopping.  Clients can call the Stop() method to
   // reset the pipeline state, and restore this to PIPELINE_OK.
   PipelineError error_;
 
   // Vector of major mime types that have been rendered by this pipeline.
   typedef std::set<std::string> RenderedMimeTypesSet;
   RenderedMimeTypesSet rendered_mime_types_;
@@ skipping 35 matching lines @@
   // Vector of threads owned by the pipeline and being used by filters.
   typedef std::vector<base::Thread*> FilterThreadVector;
   FilterThreadVector filter_threads_;
 
   DISALLOW_COPY_AND_ASSIGN(PipelineImpl);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_PIPELINE_IMPL_H_