Collapse AudioRendererMixer and OnMoreDataResampler into AudioTransform.

media/base/multi_channel_resampler.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.
 
 #ifndef MEDIA_BASE_MULTI_CHANNEL_RESAMPLER_H_
 #define MEDIA_BASE_MULTI_CHANNEL_RESAMPLER_H_
 
 #include <vector>
 
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "media/base/sinc_resampler.h"
 
 namespace media {
 class AudioBus;
 
 // MultiChannelResampler is a multi channel wrapper for SincResampler; allowing
 // high quality sample rate conversion of multiple channels at once.
 class MEDIA_EXPORT MultiChannelResampler {
  public:
   // Callback type for providing more data into the resampler.  Expects AudioBus
   // to be completely filled with data upon return; zero padded if not enough
-  // frames are available to satisfy the request.
-  typedef base::Callback<void(AudioBus* audio_bus)> ReadCB;
+  // frames are available to satisfy the request.  |frame_delay| is the number
+  // of output frames already processed and can be used to estimate delay.
+  typedef base::Callback<void(int frame_delay, AudioBus* audio_bus)> ReadCB;
 
   // Constructs a MultiChannelResampler with the specified |read_cb|, which is
   // used to acquire audio data for resampling.  |io_sample_rate_ratio| is the
   // ratio of input / output sample rates.
   MultiChannelResampler(int channels, double io_sample_rate_ratio,
                         const ReadCB& read_cb);
   virtual ~MultiChannelResampler();
 
   // Resamples |frames| of data from |read_cb_| into AudioBus.
   void Resample(AudioBus* audio_bus, int frames);
@@ skipping 13 matching lines @@
   // Source of data for resampling.
   ReadCB read_cb_;
 
   // Each channel has its own high quality resampler.
   ScopedVector<SincResampler> resamplers_;
 
   // Buffers for audio data going into SincResampler from ReadCB.
   scoped_ptr<AudioBus> resampler_audio_bus_;
   scoped_ptr<AudioBus> wrapped_resampler_audio_bus_;
   std::vector<float*> resampler_audio_data_;
+
+  // The number of output frames that have successfully been processed during
+  // the current Resample() call.
+  int output_frames_ready_;
+
+  DISALLOW_COPY_AND_ASSIGN(MultiChannelResampler);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_MULTI_CHANNEL_RESAMPLER_H_