Modifies AudioInputCallback::OnData and use media::AudioBus instead of plain byte vector (Relanding)

media/audio/mac/audio_low_latency_input_mac.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/mac/audio_low_latency_input_mac.h"
 
 #include <CoreServices/CoreServices.h>
 
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/mac/mac_logging.h"
 #include "media/audio/mac/audio_manager_mac.h"
+#include "media/base/audio_bus.h"
 #include "media/base/data_buffer.h"
 
 namespace media {
 
 static std::ostream& operator<<(std::ostream& os,
                                 const AudioStreamBasicDescription& format) {
   os << "sample rate       : " << format.mSampleRate << std::endl
      << "format ID         : " << format.mFormatID << std::endl
      << "format flags      : " << format.mFormatFlags << std::endl
      << "bytes per packet  : " << format.mBytesPerPacket << std::endl
      << "frames per packet : " << format.mFramesPerPacket << std::endl
      << "bytes per frame   : " << format.mBytesPerFrame << std::endl
      << "channels per frame: " << format.mChannelsPerFrame << std::endl
      << "bits per channel  : " << format.mBitsPerChannel;
   return os;
 }
 
 // See "Technical Note TN2091 - Device input using the HAL Output Audio Unit"
 // http://developer.apple.com/library/mac/#technotes/tn2091/_index.html
 // for more details and background regarding this implementation.
 
-AUAudioInputStream::AUAudioInputStream(
-    AudioManagerMac* manager,
-    const AudioParameters& input_params,
-    const AudioParameters& output_params,
-    AudioDeviceID audio_device_id)
+AUAudioInputStream::AUAudioInputStream(AudioManagerMac* manager,
+                                       const AudioParameters& input_params,
+                                       const AudioParameters& output_params,
+                                       AudioDeviceID audio_device_id)
     : manager_(manager),
       sink_(NULL),
       audio_unit_(0),
       input_device_id_(audio_device_id),
       started_(false),
       hardware_latency_frames_(0),
       fifo_delay_bytes_(0),
-      number_of_channels_in_frame_(0) {
+      number_of_channels_in_frame_(0),
+      audio_bus_(media::AudioBus::Create(input_params)) {
   DCHECK(manager_);
 
   // Set up the desired (output) format specified by the client.
   format_.mSampleRate = input_params.sample_rate();
   format_.mFormatID = kAudioFormatLinearPCM;
   format_.mFormatFlags = kLinearPCMFormatFlagIsPacked |
                          kLinearPCMFormatFlagIsSignedInteger;
   format_.mBitsPerChannel = input_params.bits_per_sample();
   format_.mChannelsPerFrame = input_params.channels();
   format_.mFramesPerPacket = 1;  // uncompressed audio
@@ skipping 478 matching lines @@
   // Accumulate captured audio in FIFO until we can match the output size
   // requested by the client.
   fifo_->Append(audio_data, buffer.mDataByteSize);
 
   // Deliver recorded data to the client as soon as the FIFO contains a
   // sufficient amount.
   if (fifo_->forward_bytes() >= requested_size_bytes_) {
     // Read from FIFO into temporary data buffer.
     fifo_->Read(data_->writable_data(), requested_size_bytes_);
 
+    // Copy captured (and interleaved) data into deinterleaved audio bus.
+    audio_bus_->FromInterleaved(
+        data_->data(), audio_bus_->frames(), format_.mBitsPerChannel / 8);
+
     // Deliver data packet, delay estimation and volume level to the user.
-    sink_->OnData(this,
-                  data_->data(),
-                  requested_size_bytes_,
-                  capture_delay_bytes,
-                  normalized_volume);
+    sink_->OnData(
+        this, audio_bus_.get(), capture_delay_bytes, normalized_volume);
   }
 
   return noErr;
 }
 
 int AUAudioInputStream::HardwareSampleRate() {
   // Determine the default input device's sample-rate.
   AudioDeviceID device_id = kAudioObjectUnknown;
   UInt32 info_size = sizeof(device_id);
 
@@ skipping 121 matching lines @@
     kAudioDevicePropertyScopeInput,
     static_cast<UInt32>(channel)
   };
   OSStatus result = AudioObjectIsPropertySettable(input_device_id_,
                                                   &property_address,
                                                   &is_settable);
   return (result == noErr) ? is_settable : false;
 }
 
 }  // namespace media