次のコンテキストで、AudioUnitRender からエラー -50 (無効なパラメーター) が発生します。このPitch Detectorサンプル アプリを出発点として使用していますが、問題なく動作します。私のプロジェクトの唯一の大きな違いは、オーディオ出力にもリモート I/O ユニットを使用していることです。オーディオ出力は正常に機能します。入力コールバックと初期化コードを次に示します (簡潔にするためにエラー チェックを削除しています)。たくさんあることはわかっていますが、エラー -50 からは、問題がどこにあるのかについてほとんど情報が得られません。
入力コールバック:
OSStatus inputCallback( void* inRefCon,
AudioUnitRenderActionFlags *ioActionFlags,
const AudioTimeStamp *inTimeStamp,
UInt32 inBusNumber,
UInt32 inNumberFrames,
AudioBufferList *ioData) {
WBAudio* audioObject= (WBAudio*)inRefCon;
AudioUnit rioUnit = audioObject->m_audioUnit;
OSStatus renderErr;
UInt32 bus1 = 1;
renderErr = AudioUnitRender(rioUnit, ioActionFlags,
inTimeStamp, bus1, inNumberFrames, audioObject->m_inBufferList );
if (renderErr < 0) {
return renderErr; // breaks here
}
return noErr;
} // end inputCallback()
初期化:
- (id) init {
self= [super init];
if( !self ) return nil;
OSStatus result;
//! Initialize a buffer list for rendering input
size_t bytesPerSample;
bytesPerSample = sizeof(SInt16);
m_inBufferList = (AudioBufferList *)malloc(sizeof(AudioBuffer));
m_inBufferList->mNumberBuffers = 1;
m_inBufferList->mBuffers[0].mNumberChannels = 1;
m_inBufferList->mBuffers[0].mDataByteSize = 512*bytesPerSample;
m_inBufferList->mBuffers[0].mData = calloc(512, bytesPerSample);
//! Initialize an audio session to get buffer size
result = AudioSessionInitialize(NULL, NULL, NULL, NULL);
UInt32 audioCategory = kAudioSessionCategory_PlayAndRecord;
result = AudioSessionSetProperty(kAudioSessionProperty_AudioCategory, sizeof(audioCategory), &audioCategory);
// Set preferred buffer size
Float32 preferredBufferSize = static_cast<float>(m_pBoard->m_uBufferSize) / m_pBoard->m_fSampleRate;
result = AudioSessionSetProperty(kAudioSessionProperty_PreferredHardwareIOBufferDuration, sizeof(preferredBufferSize), &preferredBufferSize);
// Get actual buffer size
Float32 audioBufferSize;
UInt32 size = sizeof (audioBufferSize);
result = AudioSessionGetProperty(kAudioSessionProperty_CurrentHardwareIOBufferDuration, &size, &audioBufferSize);
result = AudioSessionSetActive(true);
//! Create our Remote I/O component description
AudioComponentDescription desc;
desc.componentType= kAudioUnitType_Output;
desc.componentSubType= kAudioUnitSubType_RemoteIO;
desc.componentFlags= 0;
desc.componentFlagsMask= 0;
desc.componentManufacturer= kAudioUnitManufacturer_Apple;
//! Find the corresponding component
AudioComponent outputComponent = AudioComponentFindNext(NULL, &desc);
//! Create the component instance
result = AudioComponentInstanceNew(outputComponent, &m_audioUnit);
//! Enable audio output
UInt32 flag = 1;
result = AudioUnitSetProperty( m_audioUnit, kAudioOutputUnitProperty_EnableIO, kAudioUnitScope_Output, kOutputBus, &flag, sizeof(flag));
//! Enable audio input
result= AudioUnitSetProperty( m_audioUnit, kAudioOutputUnitProperty_EnableIO, kAudioUnitScope_Input, kInputBus, &flag, sizeof(flag));
//! Create our audio stream description
m_audioFormat.mSampleRate= m_pBoard->m_fSampleRate;
m_audioFormat.mFormatID= kAudioFormatLinearPCM;
m_audioFormat.mFormatFlags= kAudioFormatFlagIsSignedInteger | kAudioFormatFlagIsPacked;
m_audioFormat.mFramesPerPacket= 1;
m_audioFormat.mChannelsPerFrame= 1;
m_audioFormat.mBitsPerChannel= 16;
m_audioFormat.mBytesPerPacket= 2;
m_audioFormat.mBytesPerFrame= 2;
//! Set the stream format
result = AudioUnitSetProperty( m_audioUnit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input, kOutputBus, &m_audioFormat, sizeof(m_audioFormat));
result = AudioUnitSetProperty(m_audioUnit, kAudioUnitProperty_StreamFormat,
kAudioUnitScope_Output,
kInputBus, &m_audioFormat, sizeof(m_audioFormat));
//! Set the render callback
AURenderCallbackStruct renderCallbackStruct= {0};
renderCallbackStruct.inputProc= renderCallback;
renderCallbackStruct.inputProcRefCon= m_pBoard;
result = AudioUnitSetProperty(m_audioUnit, kAudioUnitProperty_SetRenderCallback, kAudioUnitScope_Global, kOutputBus, &renderCallbackStruct, sizeof(renderCallbackStruct));
//! Set the input callback
AURenderCallbackStruct inputCallbackStruct = {0};
inputCallbackStruct.inputProc= inputCallback;
inputCallbackStruct.inputProcRefCon= self;
result= AudioUnitSetProperty( m_audioUnit, kAudioOutputUnitProperty_SetInputCallback, kAudioUnitScope_Input, kOutputBus, &inputCallbackStruct, sizeof( inputCallbackStruct ) );
//! Initialize the unit
result = AudioUnitInitialize( m_audioUnit );
return self;
}