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Biquad.cpp
/***************************************************/
/*! \class BiQuad
\brief STK biquad (two-pole, two-zero) filter class.
This class implements a two-pole, two-zero digital filter.
Methods are provided for creating a resonance or notch in the
frequency response while maintaining a constant filter gain.
by Perry R. Cook and Gary P. Scavone, 1995--2014.
*/
/***************************************************/
#include "C:\Users\Chris\Desktop\Source\BiQuad.h"
#include <cmath>
namespace stk {
BiQuad :: BiQuad() : Filter()
{
b_.resize( 3, 0.0 );
a_.resize( 3, 0.0 );
b_[0] = 1.0;
a_[0] = 1.0;
inputs_.resize( 3, 1, 0.0 );
outputs_.resize( 3, 1, 0.0 );
Stk::addSampleRateAlert( this );
}
BiQuad :: ~BiQuad()
{
Stk::removeSampleRateAlert( this );
}
void BiQuad :: setCoefficients( StkFloat b0, StkFloat b1, StkFloat b2, StkFloat a1, StkFloat a2, bool clearState )
{
b_[0] = b0;
b_[1] = b1;
b_[2] = b2;
a_[1] = a1;
a_[2] = a2;
if ( clearState ) this->clear();
}
void BiQuad :: sampleRateChanged( StkFloat newRate, StkFloat oldRate )
{
if ( !ignoreSampleRateChange_ ) {
oStream_ << "BiQuad::sampleRateChanged: you may need to recompute filter coefficients!";
handleError( StkError::WARNING );
}
}
void BiQuad :: setResonance( StkFloat frequency, StkFloat radius, bool normalize )
{
#if defined(_STK_DEBUG_)
if ( frequency < 0.0 || frequency > 0.5 * Stk::sampleRate() ) {
oStream_ << "BiQuad::setResonance: frequency argument (" << frequency << ") is out of range!";
handleError( StkError::WARNING ); return;
}
if ( radius < 0.0 || radius >= 1.0 ) {
oStream_ << "BiQuad::setResonance: radius argument (" << radius << ") is out of range!";
handleError( StkError::WARNING ); return;
}
#endif
a_[2] = radius * radius;
a_[1] = -2.0 * radius * cos( TWO_PI * frequency / Stk::sampleRate() );
if ( normalize ) {
// Use zeros at +- 1 and normalize the filter peak gain.
b_[0] = 0.5 - 0.5 * a_[2];
b_[1] = 0.0;
b_[2] = -b_[0];
}
}
void BiQuad :: setNotch( StkFloat frequency, StkFloat radius )
{
#if defined(_STK_DEBUG_)
if ( frequency < 0.0 || frequency > 0.5 * Stk::sampleRate() ) {
oStream_ << "BiQuad::setNotch: frequency argument (" << frequency << ") is out of range!";
handleError( StkError::WARNING ); return;
}
if ( radius < 0.0 ) {
oStream_ << "BiQuad::setNotch: radius argument (" << radius << ") is negative!";
handleError( StkError::WARNING ); return;
}
#endif
// This method does not attempt to normalize the filter gain.
b_[2] = radius * radius;
b_[1] = (StkFloat) -2.0 * radius * cos( TWO_PI * (double) frequency / Stk::sampleRate() );
}
void BiQuad :: setEqualGainZeroes( void )
{
b_[0] = 1.0;
b_[1] = 0.0;
b_[2] = -1.0;
}
} // stk namespace
Raw
Biquad.h
/***************************************************/
/*! \class BiQuad
\brief STK biquad (two-pole, two-zero) filter class.
This class implements a two-pole, two-zero digital filter.
Methods are provided for creating a resonance or notch in the
frequency response while maintaining a constant filter gain.
by Perry R. Cook and Gary P. Scavone, 1995--2014.
*/
/***************************************************/
#include "C:\Users\Chris\Desktop\Source\BiQuad.h"
#include <cmath>
namespace stk {
BiQuad :: BiQuad() : Filter()
{
b_.resize( 3, 0.0 );
a_.resize( 3, 0.0 );
b_[0] = 1.0;
a_[0] = 1.0;
inputs_.resize( 3, 1, 0.0 );
outputs_.resize( 3, 1, 0.0 );
Stk::addSampleRateAlert( this );
}
BiQuad :: ~BiQuad()
{
Stk::removeSampleRateAlert( this );
}
void BiQuad :: setCoefficients( StkFloat b0, StkFloat b1, StkFloat b2, StkFloat a1, StkFloat a2, bool clearState )
{
b_[0] = b0;
b_[1] = b1;
b_[2] = b2;
a_[1] = a1;
a_[2] = a2;
if ( clearState ) this->clear();
}
void BiQuad :: sampleRateChanged( StkFloat newRate, StkFloat oldRate )
{
if ( !ignoreSampleRateChange_ ) {
oStream_ << "BiQuad::sampleRateChanged: you may need to recompute filter coefficients!";
handleError( StkError::WARNING );
}
}
void BiQuad :: setResonance( StkFloat frequency, StkFloat radius, bool normalize )
{
#if defined(_STK_DEBUG_)
if ( frequency < 0.0 || frequency > 0.5 * Stk::sampleRate() ) {
oStream_ << "BiQuad::setResonance: frequency argument (" << frequency << ") is out of range!";
handleError( StkError::WARNING ); return;
}
if ( radius < 0.0 || radius >= 1.0 ) {
oStream_ << "BiQuad::setResonance: radius argument (" << radius << ") is out of range!";
handleError( StkError::WARNING ); return;
}
#endif
a_[2] = radius * radius;
a_[1] = -2.0 * radius * cos( TWO_PI * frequency / Stk::sampleRate() );
if ( normalize ) {
// Use zeros at +- 1 and normalize the filter peak gain.
b_[0] = 0.5 - 0.5 * a_[2];
b_[1] = 0.0;
b_[2] = -b_[0];
}
}
void BiQuad :: setNotch( StkFloat frequency, StkFloat radius )
{
#if defined(_STK_DEBUG_)
if ( frequency < 0.0 || frequency > 0.5 * Stk::sampleRate() ) {
oStream_ << "BiQuad::setNotch: frequency argument (" << frequency << ") is out of range!";
handleError( StkError::WARNING ); return;
}
if ( radius < 0.0 ) {
oStream_ << "BiQuad::setNotch: radius argument (" << radius << ") is negative!";
handleError( StkError::WARNING ); return;
}
#endif
// This method does not attempt to normalize the filter gain.
b_[2] = radius * radius;
b_[1] = (StkFloat) -2.0 * radius * cos( TWO_PI * (double) frequency / Stk::sampleRate() );
}
void BiQuad :: setEqualGainZeroes( void )
{
b_[0] = 1.0;
b_[1] = 0.0;
b_[2] = -1.0;
}
} // stk namespace
Raw
Filter.h
/***************************************************/
/*! \class BiQuad
\brief STK biquad (two-pole, two-zero) filter class.
This class implements a two-pole, two-zero digital filter.
Methods are provided for creating a resonance or notch in the
frequency response while maintaining a constant filter gain.
by Perry R. Cook and Gary P. Scavone, 1995--2014.
*/
/***************************************************/
#include "C:\Users\Chris\Desktop\Source\BiQuad.h"
#include <cmath>
namespace stk {
BiQuad :: BiQuad() : Filter()
{
b_.resize( 3, 0.0 );
a_.resize( 3, 0.0 );
b_[0] = 1.0;
a_[0] = 1.0;
inputs_.resize( 3, 1, 0.0 );
outputs_.resize( 3, 1, 0.0 );
Stk::addSampleRateAlert( this );
}
BiQuad :: ~BiQuad()
{
Stk::removeSampleRateAlert( this );
}
void BiQuad :: setCoefficients( StkFloat b0, StkFloat b1, StkFloat b2, StkFloat a1, StkFloat a2, bool clearState )
{
b_[0] = b0;
b_[1] = b1;
b_[2] = b2;
a_[1] = a1;
a_[2] = a2;
if ( clearState ) this->clear();
}
void BiQuad :: sampleRateChanged( StkFloat newRate, StkFloat oldRate )
{
if ( !ignoreSampleRateChange_ ) {
oStream_ << "BiQuad::sampleRateChanged: you may need to recompute filter coefficients!";
handleError( StkError::WARNING );
}
}
void BiQuad :: setResonance( StkFloat frequency, StkFloat radius, bool normalize )
{
#if defined(_STK_DEBUG_)
if ( frequency < 0.0 || frequency > 0.5 * Stk::sampleRate() ) {
oStream_ << "BiQuad::setResonance: frequency argument (" << frequency << ") is out of range!";
handleError( StkError::WARNING ); return;
}
if ( radius < 0.0 || radius >= 1.0 ) {
oStream_ << "BiQuad::setResonance: radius argument (" << radius << ") is out of range!";
handleError( StkError::WARNING ); return;
}
#endif
a_[2] = radius * radius;
a_[1] = -2.0 * radius * cos( TWO_PI * frequency / Stk::sampleRate() );
if ( normalize ) {
// Use zeros at +- 1 and normalize the filter peak gain.
b_[0] = 0.5 - 0.5 * a_[2];
b_[1] = 0.0;
b_[2] = -b_[0];
}
}
void BiQuad :: setNotch( StkFloat frequency, StkFloat radius )
{
#if defined(_STK_DEBUG_)
if ( frequency < 0.0 || frequency > 0.5 * Stk::sampleRate() ) {
oStream_ << "BiQuad::setNotch: frequency argument (" << frequency << ") is out of range!";
handleError( StkError::WARNING ); return;
}
if ( radius < 0.0 ) {
oStream_ << "BiQuad::setNotch: radius argument (" << radius << ") is negative!";
handleError( StkError::WARNING ); return;
}
#endif
// This method does not attempt to normalize the filter gain.
b_[2] = radius * radius;
b_[1] = (StkFloat) -2.0 * radius * cos( TWO_PI * (double) frequency / Stk::sampleRate() );
}
void BiQuad :: setEqualGainZeroes( void )
{
b_[0] = 1.0;
b_[1] = 0.0;
b_[2] = -1.0;
}
} // stk namespace
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