OSStatus CAPlayThrough::InputProc(void *inRefCon,
AudioUnitRenderActionFlags *ioActionFlags,
const AudioTimeStamp *inTimeStamp,
UInt32 inBusNumber,
UInt32 inNumberFrames,
AudioBufferList * ioData)
{
OSStatus err = noErr;
CAPlayThrough *This = (CAPlayThrough *)inRefCon;
This->mutex.lock();
if (This->mFirstInputTime < 0.)
This->mFirstInputTime = inTimeStamp->mSampleTime;
//Get the new audio data
err = AudioUnitRender(This->mInputUnit,
ioActionFlags,
inTimeStamp,
inBusNumber,
inNumberFrames, //# of frames requested
This->mInputBuffer);// Audio Buffer List to hold data
checkErr(err);
if(!err) {
AEFloatConverterToFloat(This->converter,
This->mInputBuffer,
This->floatBuffers,
inNumberFrames);
This->postNotification(This->floatBuffers, inNumberFrames);
err = This->mBuffer->Store(This->mInputBuffer, Float64(inNumberFrames), SInt64(inTimeStamp->mSampleTime));
}
This->mutex.unlock();
return err;
}
OSStatus CAPlayThrough::OutputProc(void *inRefCon,
AudioUnitRenderActionFlags *ioActionFlags,
const AudioTimeStamp *TimeStamp,
UInt32 inBusNumber,
UInt32 inNumberFrames,
AudioBufferList * ioData)
{
OSStatus err = noErr;
CAPlayThrough *This = (CAPlayThrough *)inRefCon;
Float64 rate = 0.0;
AudioTimeStamp inTS, outTS;
if (This->mFirstInputTime < 0.) {
// input hasn't run yet -> silence
MakeBufferSilent (ioData);
return noErr;
}
//use the varispeed playback rate to offset small discrepancies in sample rate
//first find the rate scalars of the input and output devices
err = AudioDeviceGetCurrentTime(This->mInputDevice.mID, &inTS);
// this callback may still be called a few times after the device has been stopped
if (err)
{
MakeBufferSilent (ioData);
return noErr;
}
err = AudioDeviceGetCurrentTime(This->mOutputDevice.mID, &outTS);
checkErr(err);
rate = inTS.mRateScalar / outTS.mRateScalar;
err = AudioUnitSetParameter(This->mVarispeedUnit,kVarispeedParam_PlaybackRate,kAudioUnitScope_Global,0, rate,0);
checkErr(err);
//get Delta between the devices and add it to the offset
if (This->mFirstOutputTime < 0.) {
This->mFirstOutputTime = TimeStamp->mSampleTime;
Float64 delta = (This->mFirstInputTime - This->mFirstOutputTime);
This->ComputeThruOffset();
//changed: 3865519 11/10/04
if (delta < 0.0)
This->mInToOutSampleOffset -= delta;
else
This->mInToOutSampleOffset = -delta + This->mInToOutSampleOffset;
MakeBufferSilent (ioData);
return noErr;
}
//copy the data from the buffers
err = This->mBuffer->Fetch(ioData, inNumberFrames, SInt64(TimeStamp->mSampleTime - This->mInToOutSampleOffset));
//old line of code different once ring buffer is replaced
//err = This->mBuffer->Fetch(ioData, inNumberFrames, SInt64(TimeStamp->mSampleTime - This->mInToOutSampleOffset), false);
if(err != kCARingBufferError_OK)
{
MakeBufferSilent (ioData);
SInt64 bufferStartTime, bufferEndTime;
This->mBuffer->GetTimeBounds(bufferStartTime, bufferEndTime);
This->mInToOutSampleOffset = TimeStamp->mSampleTime - bufferStartTime;
}
return noErr;
}
OSStatus CAPlayThrough::OutputProc(void *inRefCon,
AudioUnitRenderActionFlags *ioActionFlags,
const AudioTimeStamp *TimeStamp,
UInt32 inBusNumber,
UInt32 inNumberFrames,
AudioBufferList * ioData)
{
OSStatus err = noErr;
CAPlayThrough *This = (CAPlayThrough *)inRefCon;
Float64 rate = 0.0;
AudioTimeStamp inTS, outTS;
if (This->mFirstInputTime < 0.) {
// input hasn't run yet -> silence
MakeBufferSilent (ioData);
return noErr;
}
//use the varispeed playback rate to offset small discrepancies in sample rate
//first find the rate scalars of the input and output devices
err = AudioDeviceGetCurrentTime(This->mInputDevice.mID, &inTS);
// this callback may still be called a few times after the device has been stopped
if (err)
{
MakeBufferSilent (ioData);
return noErr;
}
err = AudioDeviceGetCurrentTime(This->mOutputDevice.mID, &outTS);
checkErr(err);
rate = inTS.mRateScalar / outTS.mRateScalar;
err = AudioUnitSetParameter(This->mVarispeedUnit,kVarispeedParam_PlaybackRate,kAudioUnitScope_Global,0, rate,0);
checkErr(err);
//get Delta between the devices and add it to the offset
if (This->mFirstOutputTime < 0.) {
This->mFirstOutputTime = TimeStamp->mSampleTime;
Float64 delta = (This->mFirstInputTime - This->mFirstOutputTime);
This->ComputeThruOffset();
//changed: 3865519 11/10/04
if (delta < 0.0)
This->mInToOutSampleOffset -= delta;
else
This->mInToOutSampleOffset = -delta + This->mInToOutSampleOffset;
CAPT_DEBUG( "Set initial IOOffset to %f.\n", This->mInToOutSampleOffset );
MakeBufferSilent (ioData);
return noErr;
}
//copy the data from the buffers
err = This->mBuffer->Fetch(ioData, inNumberFrames, SInt64(TimeStamp->mSampleTime - This->mInToOutSampleOffset));
if( err != kCARingBufferError_OK ) {
SInt64 bufferStartTime, bufferEndTime;
This->mBuffer->GetTimeBounds( bufferStartTime, bufferEndTime );
CAPT_DEBUG( "Oops. Adjusting IOOffset from %f, ", This->mInToOutSampleOffset );
if ( err < kCARingBufferError_OK ) {
CAPT_DEBUG( "ahead " );
if ( err == kCARingBufferError_WayBehind ) {
MakeBufferSilent( ioData );
}
This->mInToOutSampleOffset += std::max( ( TimeStamp->mSampleTime - This->mInToOutSampleOffset ) - bufferStartTime, kAdjustmentOffsetSamples );
}
else if ( err > kCARingBufferError_OK ) {
CAPT_DEBUG( "behind " );
if ( err == kCARingBufferError_WayAhead ) {
MakeBufferSilent( ioData );
}
// Adjust by the amount that we read past in the buffer
This->mInToOutSampleOffset += std::max( ( ( TimeStamp->mSampleTime - This->mInToOutSampleOffset ) + inNumberFrames ) - bufferEndTime, kAdjustmentOffsetSamples );
}
CAPT_DEBUG( "to %f.\n", This->mInToOutSampleOffset );
MakeBufferSilent ( ioData );
}
return noErr;
}
