Remove AudioDecoder from the Filter heirarchy.

media/base/filters.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.
 
 // Filters are connected in a strongly typed manner, with downstream filters
 // always reading data from upstream filters.  Upstream filters have no clue
 // who is actually reading from them, and return the results via callbacks.
 //
 //                         DemuxerStream(Video) <- VideoDecoder <- VideoRenderer
 // DataSource <- Demuxer <
@@ skipping 20 matching lines @@
 #include "base/memory/scoped_ptr.h"
 #include "base/time.h"
 #include "media/base/channel_layout.h"
 #include "media/base/media_export.h"
 #include "media/base/pipeline_status.h"
 #include "media/base/video_frame.h"
 #include "ui/gfx/size.h"
 
 namespace media {
 
+class AudioDecoder;
 class Buffer;
 class Decoder;
 class DemuxerStream;
 class Filter;
 class FilterHost;
 
 struct PipelineStatistics;
 
 // Used for completing asynchronous methods.
 typedef base::Callback<void(PipelineStatus)> FilterStatusCB;
 
 // These functions copy |*cb|, call Reset() on |*cb|, and then call Run()
 // on the copy.  This is used in the common case where you need to clear
 // a callback member variable before running the callback.
 MEDIA_EXPORT void ResetAndRunCB(FilterStatusCB* cb, PipelineStatus status);
 MEDIA_EXPORT void ResetAndRunCB(base::Closure* cb);
 
-// Used for updating pipeline statistics.
-typedef base::Callback<void(const PipelineStatistics&)> StatisticsCallback;
-
 class MEDIA_EXPORT Filter : public base::RefCountedThreadSafe<Filter> {
  public:
   Filter();
 
   // Sets the private member |host_|. This is the first method called by
   // the FilterHost after a filter is created.  The host holds a strong
   // reference to the filter.  The reference held by the host is guaranteed
   // to be released before the host object is destroyed by the pipeline.
   virtual void set_host(FilterHost* host);
 
@@ skipping 91 matching lines @@
   // the duration.  Default implementation does nothing; derived decoders may
   // override as needed.  http://crbug.com/110228 tracks removing this.
   virtual void PrepareForShutdownHack();
 
  protected:
   VideoDecoder();
   virtual ~VideoDecoder();
 };
 
 
-class MEDIA_EXPORT AudioDecoder : public Filter {
- public:
-  // Initialize a AudioDecoder with the given DemuxerStream, executing the
-  // callback upon completion.
-  // stats_callback is used to update global pipeline statistics.
-  virtual void Initialize(DemuxerStream* stream,
-                          const PipelineStatusCB& callback,
-                          const StatisticsCallback& stats_callback) = 0;
-
-  // Request samples to be decoded and returned via the provided callback.
-  // Only one read may be in flight at any given time.
-  //
-  // Implementations guarantee that the callback will not be called from within
-  // this method.
-  //
-  // Non-NULL sample buffer pointers will contain decoded audio data or may
-  // indicate the end of the stream. A NULL buffer pointer indicates an aborted
-  // Read(). This can happen if the DemuxerStream gets flushed and doesn't have
-  // any more data to return.
-  typedef base::Callback<void(scoped_refptr<Buffer>)> ReadCB;
-  virtual void Read(const ReadCB& callback) = 0;
-
-  // Returns various information about the decoded audio format.
-  virtual int bits_per_channel() = 0;
-  virtual ChannelLayout channel_layout() = 0;
-  virtual int samples_per_second() = 0;
-
- protected:
-  AudioDecoder();
-  virtual ~AudioDecoder();
-};
-
-
 class MEDIA_EXPORT VideoRenderer : public Filter {
  public:
   // Used to update the pipeline's clock time. The parameter is the time that
   // the clock should not exceed.
   typedef base::Callback<void(base::TimeDelta)> VideoTimeCB;
 
   // Initialize a VideoRenderer with the given VideoDecoder, executing the
   // callback upon completion.
   virtual void Initialize(VideoDecoder* decoder,
                           const PipelineStatusCB& callback,
@@ skipping 12 matching lines @@
   // current time, and the second parameter is the time that the clock must not
   // exceed.
   typedef base::Callback<void(base::TimeDelta, base::TimeDelta)> AudioTimeCB;
 
   // Initialize a AudioRenderer with the given AudioDecoder, executing the
   // |init_callback| upon completion. |underflow_callback| is called when the
   // renderer runs out of data to pass to the audio card during playback.
   // If the |underflow_callback| is called ResumeAfterUnderflow() must be called
   // to resume playback. Pause(), Seek(), or Stop() cancels the underflow
   // condition.
-  virtual void Initialize(AudioDecoder* decoder,
+  virtual void Initialize(const scoped_refptr<AudioDecoder> decoder,

[scherkus (not reviewing), 2012/02/06 21:04:04]

const-ref

[Ami GONE FROM CHROMIUM, 2012/02/06 21:38:48]

Done.

                           const PipelineStatusCB& init_callback,
                           const base::Closure& underflow_callback,
                           const AudioTimeCB& time_cb) = 0;
 
   // Returns true if this filter has received and processed an end-of-stream
   // buffer.
   virtual bool HasEnded() = 0;
 
   // Sets the output volume.
   virtual void SetVolume(float volume) = 0;
 
   // Resumes playback after underflow occurs.
   // |buffer_more_audio| is set to true if you want to increase the size of the
   // decoded audio buffer.
   virtual void ResumeAfterUnderflow(bool buffer_more_audio) = 0;
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_FILTERS_H_