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// 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.
#ifndef MEDIA_AUDIO_MAC_AUDIO_UNIFIED_MAC_H_
#define MEDIA_AUDIO_MAC_AUDIO_UNIFIED_MAC_H_
#include <CoreAudio/CoreAudio.h>
#include "base/memory/scoped_ptr.h"
#include "media/audio/audio_io.h"
#include "media/audio/audio_parameters.h"
namespace media {
class AudioManagerMac;
// Implementation of AudioOutputStream for Mac OS X using the
// CoreAudio AudioHardware API suitable for low-latency unified audio I/O
// when using devices which support *both* input and output
// in the same driver. This is the case with professional
// USB and Firewire devices.
//
// Please note that it's required to first get the native sample-rate of the
// default output device and use that sample-rate when creating this object.
class AudioHardwareUnifiedStream : public AudioOutputStream {
public:
// The ctor takes all the usual parameters, plus |manager| which is the
// the audio manager who is creating this object.
AudioHardwareUnifiedStream(AudioManagerMac* manager,
const AudioParameters& params);
// The dtor is typically called by the AudioManager only and it is usually
// triggered by calling AudioOutputStream::Close().
virtual ~AudioHardwareUnifiedStream();
// Implementation of AudioOutputStream.
virtual bool Open() OVERRIDE;
virtual void Close() OVERRIDE;
virtual void Start(AudioSourceCallback* callback) OVERRIDE;
virtual void Stop() OVERRIDE;
virtual void SetVolume(double volume) OVERRIDE;
virtual void GetVolume(double* volume) OVERRIDE;
int input_channels() const { return input_channels_; }
int output_channels() const { return output_channels_; }
private:
OSStatus Render(AudioDeviceID device,
const AudioTimeStamp* now,
const AudioBufferList* input_data,
const AudioTimeStamp* input_time,
AudioBufferList* output_data,
const AudioTimeStamp* output_time);
static OSStatus RenderProc(AudioDeviceID device,
const AudioTimeStamp* now,
const AudioBufferList* input_data,
const AudioTimeStamp* input_time,
AudioBufferList* output_data,
const AudioTimeStamp* output_time,
void* user_data);
// Our creator, the audio manager needs to be notified when we close.
AudioManagerMac* manager_;
// Pointer to the object that will provide the audio samples.
AudioSourceCallback* source_;
// Structure that holds the stream format details such as bitrate.
AudioStreamBasicDescription format_;
// Hardware buffer size.
int number_of_frames_;
// Number of audio channels provided to the client via OnMoreIOData().
int client_input_channels_;
// Volume level from 0 to 1.
float volume_;
// Number of input and output channels queried from the hardware.
int input_channels_;
int output_channels_;
int input_channels_per_frame_;
int output_channels_per_frame_;
AudioDeviceIOProcID io_proc_id_;
AudioDeviceID device_;
bool is_playing_;
// Intermediate buffers used with call to OnMoreIOData().
scoped_ptr<AudioBus> input_bus_;
scoped_ptr<AudioBus> output_bus_;
DISALLOW_COPY_AND_ASSIGN(AudioHardwareUnifiedStream);
};
} // namespace media
#endif // MEDIA_AUDIO_MAC_AUDIO_UNIFIED_MAC_H_
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