CoreAudioOutput::~CoreAudioOutput()
{
OSSpinLockLock(_spinlockAU);
if(_au != NULL)
{
AudioOutputUnitStop(_au);
AudioUnitUninitialize(_au);
#if defined(MAC_OS_X_VERSION_10_6) && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_6
if (IsOSXVersionSupported(10, 6, 0))
{
AudioComponentInstanceDispose(_au);
}
else
{
CloseComponent(_au);
}
#else
CloseComponent(_au);
#endif
_au = NULL;
}
OSSpinLockUnlock(_spinlockAU);
delete _buffer;
_buffer = NULL;
free(_spinlockAU);
_spinlockAU = NULL;
}
uint8_t WhiteNoiseGenerator::generateSample()
{
#ifdef __APPLE__
#ifdef MAC_OS_X_VERSION_10_7
if (IsOSXVersionSupported(10, 7, 0))
{
return (uint8_t)(arc4random_uniform(0x00000080) & 0x7F);
}
return (uint8_t)((arc4random() % 0x00000080) & 0x7F);
#else
return (uint8_t)((arc4random() % 0x00000080) & 0x7F);
#endif
#else
return (uint8_t)(rand() & 0x7F);
#endif
}
CoreAudioOutput::CoreAudioOutput(size_t bufferSamples, size_t sampleSize)
{
OSStatus error = noErr;
_spinlockAU = (OSSpinLock *)malloc(sizeof(OSSpinLock));
*_spinlockAU = OS_SPINLOCK_INIT;
_buffer = new RingBuffer(bufferSamples, sampleSize);
_volume = 1.0f;
// Create a new audio unit
#if defined(MAC_OS_X_VERSION_10_6) && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_6
if (IsOSXVersionSupported(10, 6, 0))
{
AudioComponentDescription audioDesc;
audioDesc.componentType = kAudioUnitType_Output;
audioDesc.componentSubType = kAudioUnitSubType_DefaultOutput;
audioDesc.componentManufacturer = kAudioUnitManufacturer_Apple;
audioDesc.componentFlags = 0;
audioDesc.componentFlagsMask = 0;
AudioComponent audioComponent = AudioComponentFindNext(NULL, &audioDesc);
if (audioComponent == NULL)
{
return;
}
error = AudioComponentInstanceNew(audioComponent, &_au);
if (error != noErr)
{
return;
}
}
else
{
ComponentDescription audioDesc;
audioDesc.componentType = kAudioUnitType_Output;
audioDesc.componentSubType = kAudioUnitSubType_DefaultOutput;
audioDesc.componentManufacturer = kAudioUnitManufacturer_Apple;
audioDesc.componentFlags = 0;
audioDesc.componentFlagsMask = 0;
Component audioComponent = FindNextComponent(NULL, &audioDesc);
if (audioComponent == NULL)
{
return;
}
error = OpenAComponent(audioComponent, &_au);
if (error != noErr)
{
return;
}
}
#else
ComponentDescription audioDesc;
audioDesc.componentType = kAudioUnitType_Output;
audioDesc.componentSubType = kAudioUnitSubType_DefaultOutput;
audioDesc.componentManufacturer = kAudioUnitManufacturer_Apple;
audioDesc.componentFlags = 0;
audioDesc.componentFlagsMask = 0;
Component audioComponent = FindNextComponent(NULL, &audioDesc);
if (audioComponent == NULL)
{
return;
}
error = OpenAComponent(audioComponent, &_au);
if (error != noErr)
{
return;
}
#endif
// Set the render callback
AURenderCallbackStruct callback;
callback.inputProc = &CoreAudioOutputRenderCallback;
callback.inputProcRefCon = _buffer;
error = AudioUnitSetProperty(_au,
kAudioUnitProperty_SetRenderCallback,
kAudioUnitScope_Input,
0,
&callback,
sizeof(callback) );
if(error != noErr)
{
return;
}
// Set up the audio unit for audio streaming
AudioStreamBasicDescription outputFormat;
outputFormat.mSampleRate = SPU_SAMPLE_RATE;
outputFormat.mFormatID = kAudioFormatLinearPCM;
outputFormat.mFormatFlags = kAudioFormatFlagIsSignedInteger | kAudioFormatFlagsNativeEndian | kLinearPCMFormatFlagIsPacked;
outputFormat.mBytesPerPacket = SPU_SAMPLE_SIZE;
outputFormat.mFramesPerPacket = 1;
outputFormat.mBytesPerFrame = SPU_SAMPLE_SIZE;
outputFormat.mChannelsPerFrame = SPU_NUMBER_CHANNELS;
outputFormat.mBitsPerChannel = SPU_SAMPLE_RESOLUTION;
error = AudioUnitSetProperty(_au,
kAudioUnitProperty_StreamFormat,
kAudioUnitScope_Input,
0,
&outputFormat,
sizeof(outputFormat) );
if(error != noErr)
{
return;
}
// Initialize our new audio unit
error = AudioUnitInitialize(_au);
if(error != noErr)
{
return;
}
}
