Switch AudioRenderSink::Callback to use AudioBus.

media/base/audio_renderer_mixer.cc

Index: media/base/audio_renderer_mixer.cc
diff --git a/media/base/audio_renderer_mixer.cc b/media/base/audio_renderer_mixer.cc
index 1ca2f39f7f58d8cff456ba3c7623a974a8da870d..503f139fdc52f1fd1179db5972e6ae799922c27e 100644
--- a/media/base/audio_renderer_mixer.cc
+++ b/media/base/audio_renderer_mixer.cc
@@ -46,11 +46,6 @@ AudioRendererMixer::~AudioRendererMixer() {
   // AudioRendererSinks must be stopped before being destructed.
   audio_sink_->Stop();
 
-  // Clean up |mixer_input_audio_data_|.
-  for (size_t i = 0; i < mixer_input_audio_data_.size(); ++i)
-    base::AlignedFree(mixer_input_audio_data_[i]);
-  mixer_input_audio_data_.clear();
-
   // Ensures that all mixer inputs have stopped themselves prior to destruction
   // and have called RemoveMixerInput().
   DCHECK_EQ(mixer_inputs_.size(), 0U);
@@ -68,45 +63,40 @@ void AudioRendererMixer::RemoveMixerInput(
   mixer_inputs_.erase(input);
 }
 
-int AudioRendererMixer::Render(const std::vector<float*>& audio_data,
-                               int number_of_frames,
+int AudioRendererMixer::Render(AudioBus* audio_bus,
                                int audio_delay_milliseconds) {
   current_audio_delay_milliseconds_ = audio_delay_milliseconds;
 
   if (resampler_.get())
-    resampler_->Resample(audio_data, number_of_frames);
+    resampler_->Resample(audio_bus, audio_bus->frames());
   else
-    ProvideInput(audio_data, number_of_frames);
+    ProvideInput(audio_bus);
 
   // Always return the full number of frames requested, ProvideInput() will pad
   // with silence if it wasn't able to acquire enough data.
-  return number_of_frames;
+  return audio_bus->frames();
 }
 
-void AudioRendererMixer::ProvideInput(const std::vector<float*>& audio_data,
-                                      int number_of_frames) {
+void AudioRendererMixer::ProvideInput(AudioBus* audio_bus) {
   base::AutoLock auto_lock(mixer_inputs_lock_);
 
   // Allocate staging area for each mixer input's audio data on first call.  We
-  // won't know how much to allocate until here because of resampling.
-  if (mixer_input_audio_data_.size() == 0) {
-    mixer_input_audio_data_.reserve(audio_data.size());
-    for (size_t i = 0; i < audio_data.size(); ++i) {
-      // Allocate audio data with a 16-byte alignment for SSE optimizations.
-      mixer_input_audio_data_.push_back(static_cast<float*>(
-          base::AlignedAlloc(sizeof(float) * number_of_frames, 16)));
-    }
-    mixer_input_audio_data_size_ = number_of_frames;
+  // won't know how much to allocate until here because of resampling.  Ensure
+  // our intermediate AudioBus is sized exactly as the original.  Resize should
+  // only happen once due to the way the resampler works.
+  if (!mixer_input_audio_bus_.get() ||
+      mixer_input_audio_bus_->frames() != audio_bus->frames()) {
+    mixer_input_audio_bus_ =
+        AudioBus::Create(audio_bus->channels(), audio_bus->frames());
   }
 
   // Sanity check our inputs.
-  DCHECK_LE(number_of_frames, mixer_input_audio_data_size_);
-  DCHECK_EQ(audio_data.size(), mixer_input_audio_data_.size());
+  DCHECK_EQ(audio_bus->frames(), mixer_input_audio_bus_->frames());
+  DCHECK_EQ(audio_bus->channels(), mixer_input_audio_bus_->channels());
 
-  // Zero |audio_data| so we're mixing into a clean buffer and return silence if
+  // Zero |audio_bus| so we're mixing into a clean buffer and return silence if
   // we couldn't get enough data from our inputs.
-  for (size_t i = 0; i < audio_data.size(); ++i)
-    memset(audio_data[i], 0, number_of_frames * sizeof(*audio_data[i]));
+  audio_bus->Zero();
 
   // Have each mixer render its data into an output buffer then mix the result.
   for (AudioRendererMixerInputSet::iterator it = mixer_inputs_.begin();
@@ -121,15 +111,14 @@ void AudioRendererMixer::ProvideInput(const std::vector<float*>& audio_data,
       continue;
 
     int frames_filled = input->callback()->Render(
-        mixer_input_audio_data_, number_of_frames,
-        current_audio_delay_milliseconds_);
+        mixer_input_audio_bus_.get(), current_audio_delay_milliseconds_);
     if (frames_filled == 0)
       continue;
 
-    // Volume adjust and mix each mixer input into |audio_data| after rendering.
-    for (size_t j = 0; j < audio_data.size(); ++j) {
-       VectorFMAC(
-           mixer_input_audio_data_[j], volume, frames_filled, audio_data[j]);
+    // Volume adjust and mix each mixer input into |audio_bus| after rendering.
+    for (int i = 0; i < audio_bus->channels(); ++i) {
+       VectorFMAC(mixer_input_audio_bus_->channel(i), volume, frames_filled,
+                  audio_bus->channel(i));
     }
 
     // No need to clamp values as InterleaveFloatToInt() will take care of this