mirror of
https://github.com/thestk/stk
synced 2026-01-11 20:11:52 +00:00
86 lines
2.0 KiB
C++
86 lines
2.0 KiB
C++
/***************************************************/
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/*! \class PitShift
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\brief STK simple pitch shifter effect class.
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This class implements a simple pitch shifter
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using a delay line.
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by Perry R. Cook and Gary P. Scavone, 1995--2021.
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*/
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/***************************************************/
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#include "PitShift.h"
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#include <cmath>
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namespace stk {
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PitShift :: PitShift( void )
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{
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delayLength_ = maxDelay - 24;
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halfLength_ = delayLength_ / 2;
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delay_[0] = 12;
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delay_[1] = maxDelay / 2;
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delayLine_.setMaximumDelay( maxDelay );
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delayLine_.setDelay( delay_[0] );
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effectMix_ = 0.5;
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rate_ = 1.0;
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}
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void PitShift :: clear()
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{
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delayLine_.clear();
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lastFrame_[0] = 0.0;
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}
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void PitShift :: setShift( StkFloat shift )
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{
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if ( shift < 1.0 ) {
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rate_ = 1.0 - shift;
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}
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else if ( shift > 1.0 ) {
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rate_ = 1.0 - shift;
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}
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else {
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rate_ = 0.0;
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delay_[0] = halfLength_ + 12;
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}
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}
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StkFrames& PitShift :: tick( StkFrames& frames, unsigned int channel )
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{
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#if defined(_STK_DEBUG_)
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if ( channel >= frames.channels() ) {
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oStream_ << "PitShift::tick(): channel and StkFrames arguments are incompatible!";
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handleError( StkError::FUNCTION_ARGUMENT );
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}
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#endif
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StkFloat *samples = &frames[channel];
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unsigned int hop = frames.channels();
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for ( unsigned int i=0; i<frames.frames(); i++, samples += hop )
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*samples = tick( *samples );
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return frames;
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}
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StkFrames& PitShift :: tick( StkFrames& iFrames, StkFrames& oFrames, unsigned int iChannel, unsigned int oChannel )
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{
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#if defined(_STK_DEBUG_)
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if ( iChannel >= iFrames.channels() || oChannel >= oFrames.channels() ) {
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oStream_ << "PitShift::tick(): channel and StkFrames arguments are incompatible!";
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handleError( StkError::FUNCTION_ARGUMENT );
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}
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#endif
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StkFloat *iSamples = &iFrames[iChannel];
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StkFloat *oSamples = &oFrames[oChannel];
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unsigned int iHop = iFrames.channels(), oHop = oFrames.channels();
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for ( unsigned int i=0; i<iFrames.frames(); i++, iSamples += iHop, oSamples += oHop )
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*oSamples = tick( *iSamples );
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return iFrames;
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}
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} // stk namespace
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