Almost complete implementation of the Chrome video renderer. Still needs to ...

media/base/pipeline.h

 // Copyright (c) 2006-2009 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.
 
 // The pipeline is the public API clients use for playing back media.  Clients
 // provide a filter factory containing the filters they want the pipeline to
 // use to render media.
 
 #ifndef MEDIA_BASE_PIPELINE_H_
 #define MEDIA_BASE_PIPELINE_H_
@@ skipping 52 matching lines @@
   // the pipeline is started, this value will be 1.0f.  Valid values range
   // from 0.0f to 1.0f.
   virtual float GetVolume() const = 0;
 
   // Gets the current playback rate of the pipeline.  When the pipeline is
   // started, the playback rate will be 0.0f.  A rate of 1.0f indicates
   // that the pipeline is rendering the media at the standard rate.  Valid
   // values for playback rate are >= 0.0f.
   virtual float GetPlaybackRate() const = 0;
 
-  // Gets the current pipeline time in microseconds.  For a pipeline "time"
-  // progresses from 0 to the end of the media.
+  // Gets the current pipeline time in microseconds. For a pipeline "time"
+  // progresses from 0 to the end of the media. This time base is updated
+  // by the audio renderer to allow for synchronization of audio and video.
+  // Note that a more accurate time may be obtained by calling the
+  // GetInterpolatedTime method which estimates the position of the audio
+  // device based on a combination of the last time the audio device reported
+  // it's position and the current system time.
   virtual base::TimeDelta GetTime() const = 0;
 
+  // Gets the current pipeline time in microseconds. For a pipeline "time"
+  // progresses from 0 to the end of the media. Becuase this method provides
+  // an estimated time, it is possible that subsequent calls to this method will
+  // actually progress backwards slightly, so callers must not assume that this
+  // method will always return times larger than the last one.
+  virtual base::TimeDelta GetInterpolatedTime() const = 0;
+
   // Gets the current error status for the pipeline.  If the pipeline is
   // operating correctly, this will return OK.
   virtual PipelineError GetError() const = 0;
 
  protected:
   virtual ~PipelineStatus() {}
 };
 
 
 class Pipeline : public PipelineStatus {
@@ skipping 54 matching lines @@
   // This method must be called only after initialization has completed.
   virtual void SetVolume(float volume) = 0;
 
  protected:
   virtual ~Pipeline() {}
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_PIPELINE_H_