Reland 10952007: Pass through small buffer sizes without FIFO on Linux

media/audio/audio_output_resampler.cc

Index: media/audio/audio_output_resampler.cc
diff --git a/media/audio/audio_output_resampler.cc b/media/audio/audio_output_resampler.cc
index 73765cdf6ec821bb5ffc79a0b8fe33777d056485..496fe4f4d17c28f8233dcd1eac7142f9bf2b9831 100644
--- a/media/audio/audio_output_resampler.cc
+++ b/media/audio/audio_output_resampler.cc
@@ -199,6 +199,20 @@ AudioOutputResampler::~AudioOutputResampler() {}
 void AudioOutputResampler::Initialize() {
   io_ratio_ = 1;
 
+  double in_buffer_s = static_cast<double>(params_.frames_per_buffer()) /
+      static_cast<double>(params_.sample_rate());
+  double out_buffer_s =
+      static_cast<double>(output_params_.frames_per_buffer()) /
+          static_cast<double>(output_params_.sample_rate());
+  if (in_buffer_s != out_buffer_s) {
+    int out_buffer_size = static_cast<int>(
+        in_buffer_s * output_params_.sample_rate() + 0.5);
+    output_params_.Reset(output_params_.format(),
+                           output_params_.channel_layout(),
+                           output_params_.sample_rate(),
+                           output_params_.bits_per_sample(),
+                           out_buffer_size);
+  }

[Chris Rogers, 2012/09/18 17:36:29]

Why do we need special logic here when we have
AudioManagerBase::GetPreferredLowLatencyOutputStreamParameters().  Can't this
method be made to do the right thing for all platforms?

   // TODO(dalecurtis): Add channel remixing.  http://crbug.com/138762
   DCHECK_EQ(params_.channels(), output_params_.channels());
   // Only resample or rebuffer if the input parameters don't match the output