/* * File: PrimeFIR.cpp * * Version: 1.0 * * Created: 3/24/25 * * Copyright: Copyright © 2025 Airwindows, Airwindows uses the MIT license * * Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple Computer, Inc. ("Apple") in * consideration of your agreement to the following terms, and your use, installation, modification * or redistribution of this Apple software constitutes acceptance of these terms. 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APPLE MAKES NO WARRANTIES, EXPRESS OR * IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY * AND FITNESS FOR A PARTICULAR PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND OPERATION ALONE * OR IN COMBINATION WITH YOUR PRODUCTS. * * IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) ARISING IN ANY WAY OUT OF THE USE, * REPRODUCTION, MODIFICATION AND/OR DISTRIBUTION OF THE APPLE SOFTWARE, HOWEVER CAUSED AND WHETHER * UNDER THEORY OF CONTRACT, TORT (INCLUDING NEGLIGENCE), STRICT LIABILITY OR OTHERWISE, EVEN * IF APPLE HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */ /*============================================================================= PrimeFIR.cpp =============================================================================*/ #include "PrimeFIR.h" //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ AUDIOCOMPONENT_ENTRY(AUBaseFactory, PrimeFIR) //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ // PrimeFIR::PrimeFIR //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PrimeFIR::PrimeFIR(AudioUnit component) : AUEffectBase(component) { CreateElements(); Globals()->UseIndexedParameters(kNumberOfParameters); SetParameter(kParam_A, kDefaultValue_ParamA ); SetParameter(kParam_B, kDefaultValue_ParamB ); SetParameter(kParam_C, kDefaultValue_ParamC ); #if AU_DEBUG_DISPATCHER mDebugDispatcher = new AUDebugDispatcher (this); #endif } //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ // PrimeFIR::GetParameterValueStrings //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ComponentResult PrimeFIR::GetParameterValueStrings(AudioUnitScope inScope, AudioUnitParameterID inParameterID, CFArrayRef * outStrings) { return kAudioUnitErr_InvalidProperty; } //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ // PrimeFIR::GetParameterInfo //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ComponentResult PrimeFIR::GetParameterInfo(AudioUnitScope inScope, AudioUnitParameterID inParameterID, AudioUnitParameterInfo &outParameterInfo ) { ComponentResult result = noErr; outParameterInfo.flags = kAudioUnitParameterFlag_IsWritable | kAudioUnitParameterFlag_IsReadable; if (inScope == kAudioUnitScope_Global) { switch(inParameterID) { case kParam_A: AUBase::FillInParameterName (outParameterInfo, kParameterAName, false); outParameterInfo.unit = kAudioUnitParameterUnit_Generic; outParameterInfo.minValue = 0.0; outParameterInfo.maxValue = 1.0; outParameterInfo.defaultValue = kDefaultValue_ParamA; break; case kParam_B: AUBase::FillInParameterName (outParameterInfo, kParameterBName, false); outParameterInfo.unit = kAudioUnitParameterUnit_Generic; outParameterInfo.minValue = 0.0; outParameterInfo.maxValue = 1.0; outParameterInfo.defaultValue = kDefaultValue_ParamB; break; case kParam_C: AUBase::FillInParameterName (outParameterInfo, kParameterCName, false); outParameterInfo.unit = kAudioUnitParameterUnit_Generic; outParameterInfo.minValue = 0.0; outParameterInfo.maxValue = 1.0; outParameterInfo.defaultValue = kDefaultValue_ParamC; break; default: result = kAudioUnitErr_InvalidParameter; break; } } else { result = kAudioUnitErr_InvalidParameter; } return result; } //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ // PrimeFIR::GetPropertyInfo //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ComponentResult PrimeFIR::GetPropertyInfo (AudioUnitPropertyID inID, AudioUnitScope inScope, AudioUnitElement inElement, UInt32 & outDataSize, Boolean & outWritable) { return AUEffectBase::GetPropertyInfo (inID, inScope, inElement, outDataSize, outWritable); } //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ // PrimeFIR::GetProperty //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ComponentResult PrimeFIR::GetProperty( AudioUnitPropertyID inID, AudioUnitScope inScope, AudioUnitElement inElement, void * outData ) { return AUEffectBase::GetProperty (inID, inScope, inElement, outData); } // PrimeFIR::Initialize //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ComponentResult PrimeFIR::Initialize() { ComponentResult result = AUEffectBase::Initialize(); if (result == noErr) Reset(kAudioUnitScope_Global, 0); return result; } #pragma mark ____PrimeFIREffectKernel //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ // PrimeFIR::PrimeFIRKernel::Reset() //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ void PrimeFIR::PrimeFIRKernel::Reset() { for(int count = 0; count < 32767; count++) {firBuffer[count] = 0.0;} firPosition = 0; fpd = 1.0; while (fpd < 16386) fpd = rand()*UINT32_MAX; } //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ // PrimeFIR::PrimeFIRKernel::Process //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ void PrimeFIR::PrimeFIRKernel::Process( const Float32 *inSourceP, Float32 *inDestP, UInt32 inFramesToProcess, UInt32 inNumChannels, bool &ioSilence ) { UInt32 nSampleFrames = inFramesToProcess; const Float32 *sourceP = inSourceP; Float32 *destP = inDestP; double overallscale = 1.0; overallscale /= 44100.0; overallscale *= GetSampleRate(); double freq = pow(GetParameter( kParam_A ),2)*M_PI_2; if (freq < 0.0001) freq = 0.0001; double positionMiddle = sin(freq)*0.5; //shift relative to frequency, not sample-rate freq /= overallscale; //generating the FIR relative to sample rate int window = (int)(GetParameter( kParam_B )*256.0*overallscale); //so's the window size if (window < 2) window = 2; if (window > 998) window = 998; double fir[window+2]; int middle = (int)((double)window*positionMiddle); bool nonPrime = (GetParameter( kParam_C ) < 0.5); if (nonPrime) { for(int fip = 0; fip < middle; fip++) { fir[fip] = (fip-middle)*freq; fir[fip] = sin(fir[fip])/fir[fip]; //sinc function fir[fip] *= sin(((double)fip/(double)window)*M_PI); //windowed with sin() } fir[middle] = 1.0; for(int fip = middle+1; fip < window; fip++) { fir[fip] = (fip-middle)*freq; fir[fip] = sin(fir[fip])/fir[fip]; //sinc function fir[fip] *= sin(((double)fip/(double)window)*M_PI); //windowed with sin() } } else { for(int fip = 0; fip < middle; fip++) { fir[fip] = (prime[middle-fip])*freq; fir[fip] = sin(fir[fip])/fir[fip]; //sinc function fir[fip] *= sin(((double)fip/(double)window)*M_PI); //windowed with sin() } fir[middle] = 1.0; for(int fip = middle+1; fip < window; fip++) { fir[fip] = (prime[fip-middle])*freq; fir[fip] = sin(fir[fip])/fir[fip]; //sinc function fir[fip] *= sin(((double)fip/(double)window)*M_PI); //windowed with sin() } } while (nSampleFrames-- > 0) { double inputSample = *sourceP; if (fabs(inputSample)<1.18e-23) inputSample = fpd * 1.18e-17; if (firPosition < 0 || firPosition > 32767) firPosition = 32767; int firp = firPosition; firBuffer[firp] = inputSample; inputSample = 0.0; if (nonPrime) { if (firp + window < 32767) { for(int fip = 1; fip < window; fip++) { inputSample += firBuffer[firp+fip] * fir[fip]; } } else { for(int fip = 1; fip < window; fip++) { inputSample += firBuffer[firp+fip - ((firp+fip > 32767)?32768:0)] * fir[fip]; } } inputSample *= 0.25; } else { if (firp + prime[window] < 32767) { for(int fip = 1; fip < window; fip++) { inputSample += firBuffer[firp+prime[fip]] * fir[fip]; } } else { for(int fip = 1; fip < window; fip++) { inputSample += firBuffer[firp+prime[fip] - ((firp+prime[fip] > 32767)?32768:0)] * fir[fip]; } } inputSample *= 0.5; } inputSample *= sqrt(freq); //compensate for gain firPosition--; //begin 32 bit floating point dither int expon; frexpf((float)inputSample, &expon); fpd ^= fpd << 13; fpd ^= fpd >> 17; fpd ^= fpd << 5; inputSample += ((double(fpd)-uint32_t(0x7fffffff)) * 5.5e-36l * pow(2,expon+62)); //end 32 bit floating point dither *destP = inputSample; sourceP += inNumChannels; destP += inNumChannels; } }