Add support for midstream audio configuration changes.

media/filters/audio_renderer_impl.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.
 
 // Audio rendering unit utilizing an AudioRendererSink to output data.
 //
 // This class lives inside three threads during it's lifetime, namely:
 // 1. Render thread
 //    Where the object is created.
 // 2. Media thread (provided via constructor)
@@ skipping 20 matching lines @@
 #include "media/filters/audio_renderer_algorithm.h"
 #include "media/filters/decoder_stream.h"
 
 namespace base {
 class SingleThreadTaskRunner;
 }
 
 namespace media {
 
 class AudioBus;
+class AudioBufferConverter;
 class AudioSplicer;
 class DecryptingDemuxerStream;
+class AudioHardwareConfig;
 
 class MEDIA_EXPORT AudioRendererImpl
     : public AudioRenderer,
       NON_EXPORTED_BASE(public AudioRendererSink::RenderCallback) {
  public:
   // |task_runner| is the thread on which AudioRendererImpl will execute.
   //
   // |sink| is used as the destination for the rendered audio.
   //
   // |decoders| contains the AudioDecoders to use when initializing.
   //
   // |set_decryptor_ready_cb| is fired when the audio decryptor is available
   // (only applicable if the stream is encrypted and we have a decryptor).
   AudioRendererImpl(
       const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
       AudioRendererSink* sink,
       ScopedVector<AudioDecoder> decoders,
-      const SetDecryptorReadyCB& set_decryptor_ready_cb);
+      const SetDecryptorReadyCB& set_decryptor_ready_cb,
+      const AudioHardwareConfig& hardware_params);
   virtual ~AudioRendererImpl();
 
   // AudioRenderer implementation.
   virtual void Initialize(DemuxerStream* stream,
                           const PipelineStatusCB& init_cb,
                           const StatisticsCB& statistics_cb,
                           const base::Closure& underflow_cb,
                           const TimeCB& time_cb,
                           const base::Closure& ended_cb,
                           const base::Closure& disabled_cb,
@@ skipping 104 matching lines @@
   // Calls |decoder_|.Reset() and arranges for ResetDecoderDone() to get
   // called when the reset completes.
   void ResetDecoder();
 
   // Called when the |decoder_|.Reset() has completed.
   void ResetDecoderDone();
 
   // Called by the AudioBufferStream when a splice buffer is demuxed.
   void OnNewSpliceBuffer(base::TimeDelta);
 
+  // Called by the AudioBufferStream when a config change occurs.
+  void OnConfigChange();
+
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
 
   scoped_ptr<AudioSplicer> splicer_;
+  scoped_ptr<AudioBufferConverter> buffer_converter_;
+
+  // Whether or not we expect to handle config changes.
+  bool expecting_config_changes_;
 
   // The sink (destination) for rendered audio. |sink_| must only be accessed
   // on |task_runner_|. |sink_| must never be called under |lock_| or else we
   // may deadlock between |task_runner_| and the audio callback thread.
   scoped_refptr<media::AudioRendererSink> sink_;
 
   AudioBufferStream audio_buffer_stream_;
 
-  // AudioParameters constructed during Initialize().
+  // Interface to the hardware audio params.
+  const AudioHardwareConfig& hardware_config_;

[DaleCurtis, 2014/03/27 06:00:45]

storing const& is unusual in CHrome land. I'd check the style guide :)

[rileya (GONE FROM CHROMIUM), 2014/03/27 17:51:40]

Changed to a pointer.

+
+  // Cached copy of hardware params from |hardware_config_|.
   AudioParameters audio_parameters_;
 
   // Callbacks provided during Initialize().
   PipelineStatusCB init_cb_;
   base::Closure underflow_cb_;
   TimeCB time_cb_;
   base::Closure ended_cb_;
   base::Closure disabled_cb_;
   PipelineStatusCB error_cb_;
 
@@ skipping 60 matching lines @@
 
   // NOTE: Weak pointers must be invalidated before all other member variables.
   base::WeakPtrFactory<AudioRendererImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioRendererImpl);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_AUDIO_RENDERER_IMPL_H_