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 34343d75337c6598126a3696f252690a9bdfdefb..c945aae4ad4adf1530d8978d8452eda6a59b352f 100644
--- a/media/audio/audio_output_resampler.cc
+++ b/media/audio/audio_output_resampler.cc
@@ -132,6 +132,16 @@ void AudioOutputResampler::Initialize() {
     io_ratio_ *= static_cast<double>(params_.channels()) /
         output_params_.channels();
 
+    // We allow the clients to set the buffer size for low latency path.
+    if (output_params_.format() == AudioParameters::AUDIO_PCM_LOW_LATENCY &&
+        params_.frames_per_buffer() != output_params_.frames_per_buffer()) {

[scherkus (not reviewing), 2012/09/17 16:27:23]

doesn't this essentially disable the FIFO when sample rates match?

[no longer working on chromium, 2012/09/17 21:56:28]

True, we should not do this.

+      output_params_.Reset(output_params_.format(),
+                           output_params_.channel_layout(),
+                           output_params_.sample_rate(),
+                           output_params_.bits_per_sample(),
+                           params_.frames_per_buffer());
+    }
+
     // Since the resampler / output device may want a different buffer size than
     // the caller asked for, we need to use a FIFO to ensure that both sides
     // read in chunk sizes they're configured for.