Moved AudioUtil static functions to AudioManager interfaces

media/audio/android/audio_manager_android.cc

 // 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.
 
 #include "media/audio/android/audio_manager_android.h"
 
 #include "base/logging.h"
 #include "media/audio/android/opensles_input.h"
 #include "media/audio/android/opensles_output.h"
 #include "media/audio/audio_manager.h"
-#include "media/audio/audio_util.h"
+#include "media/audio/audio_parameters.h"
 #include "media/audio/fake_audio_input_stream.h"
+#include "media/base/channel_layout.h"
 
 namespace media {
 
 // Maximum number of output streams that can be open simultaneously.
 static const int kMaxOutputStreams = 10;
 
 AudioManager* CreateAudioManager() {
   return new AudioManagerAndroid();
 }
 
@@ skipping 13 matching lines @@
   return true;
 }
 
 void AudioManagerAndroid::GetAudioInputDeviceNames(
     media::AudioDeviceNames* device_names) {
   DCHECK(device_names->empty());
   device_names->push_front(
       media::AudioDeviceName(kDefaultDeviceName, kDefaultDeviceId));
 }
 
+AudioParameters AudioManagerAndroid::GetDefaultOutputStreamParameters() {
+  // TODO(xians): figure out the right output sample rate and sample rate to
+  // achieve the best audio performance for Android devices.
+  static const int kDefaultSampleRate = 16000;
+  static const int kDefaultBufferSize = 1024
+  return AudioParameters(
+      AudioParameters::AUDIO_PCM_LOW_LATENCY, CHANNEL_LAYOUT_STEREO,
+      kDefaultSampleRate, 16, kDefaultBufferSize);
+}
+
+AudioParameters AudioManagerAndroid::GetDefaultInputStreamParameters(
+    const std::string& device_id) {
+  // TODO(xians): figure out the right input sample rate and buffer size to
+  // achieve the best audio performance for Android devices.
+  // TODO(xians): query the native channel layout for the specific device.
+  static const int kDefaultSampleRate = 16000;
+  static const int kDefaultBufferSize = 1024

[Raymond Toy (Google), 2013/02/28 00:30:45]

Didn't this used to be 2048?  Is 1024 the desired value now?

[no longer working on chromium, 2013/03/01 16:44:33]

Yes, it used to be 2048, but I think 2048 to 16K is too much, it means 120.8ms
buffer, isn't fine to reduce it to half?

We can fall back to the old value if you think we should keep 2048.

+  return AudioParameters(
+      AudioParameters::AUDIO_PCM_LOW_LATENCY, CHANNEL_LAYOUT_STEREO,
+      kDefaultSampleRate, 16, kDefaultBufferSize);
+}
+
 AudioParameters
 AudioManagerAndroid::GetPreferredLowLatencyOutputStreamParameters(
     const AudioParameters& input_params) {
-  // TODO(leozwang): Android defines the minimal buffer size requirment
+  // TODO(leozwang): Android defines the minimal buffer size requirement
   // we should follow it. From Android 4.1, a new audio low latency api
   // set was introduced and is under development, we want to take advantage
   // of it.
-  int buffer_size = GetAudioHardwareBufferSize();
-  if (input_params.frames_per_buffer() < buffer_size)
-    buffer_size = input_params.frames_per_buffer();
+  AudioParameters default_params = GetDefaultOutputStreamParameters();
+  int buffer_size = std::min(input_params.frames_per_buffer(),
+                             default_params.frames_per_buffer())
 
   return AudioParameters(
       AudioParameters::AUDIO_PCM_LOW_LATENCY, input_params.channel_layout(),
       input_params.sample_rate(), 16, buffer_size);
 }
 
 AudioOutputStream* AudioManagerAndroid::MakeLinearOutputStream(
       const AudioParameters& params) {
   DCHECK_EQ(AudioParameters::AUDIO_PCM_LINEAR, params.format());
   return new OpenSLESOutputStream(this, params);
@@ skipping 11 matching lines @@
   return new OpenSLESInputStream(this, params);
 }
 
 AudioInputStream* AudioManagerAndroid::MakeLowLatencyInputStream(
     const AudioParameters& params, const std::string& device_id) {
   DCHECK_EQ(AudioParameters::AUDIO_PCM_LOW_LATENCY, params.format());
   return new OpenSLESInputStream(this, params);
 }
 
 }  // namespace media