e1lama/stk
1
0
Fork 0
mirror of https://github.com/thestk/stk synced 2026-01-16 14:21:53 +00:00
Code Issues Packages Projects Releases Wiki Activity

Version 4.4.0

Browse Source
This commit is contained in:
Gary Scavone
2013-09-29 23:11:39 +02:00
committed by Stephen Sinclair
parent d199342e86
commit eccd8c9981
287 changed files with 11712 additions and 7676 deletions
Download Patch File Download Diff File Expand all files Collapse all files

84
src/BiQuad.cpp
View File

@@ -2,26 +2,28 @@
/*! \class BiQuad
\brief STK biquad (two-pole, two-zero) filter class.
This protected Filter subclass implements a
two-pole, two-zero digital filter. A method
is provided for creating a resonance in the
frequency response while maintaining a constant
filter gain.
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 - 2007.
by Perry R. Cook and Gary P. Scavone, 1995 - 2009.
*/
/***************************************************/
#include "BiQuad.h"
#include <cmath>
namespace stk {
BiQuad :: BiQuad() : Filter()
{
std::vector<StkFloat> b(3, 0.0);
std::vector<StkFloat> a(3, 0.0);
b[0] = 1.0;
a[0] = 1.0;
Filter::setCoefficients( b, a );
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 );
}
@@ -30,6 +32,17 @@ 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_ ) {
@@ -38,40 +51,10 @@ void BiQuad :: sampleRateChanged( StkFloat newRate, StkFloat oldRate )
}
}
void BiQuad :: clear(void)
{
Filter::clear();
}
void BiQuad :: setB0(StkFloat b0)
{
b_[0] = b0;
}
void BiQuad :: setB1(StkFloat b1)
{
b_[1] = b1;
}
void BiQuad :: setB2(StkFloat b2)
{
b_[2] = b2;
}
void BiQuad :: setA1(StkFloat a1)
{
a_[1] = a1;
}
void BiQuad :: setA2(StkFloat a2)
{
a_[2] = a2;
}
void BiQuad :: setResonance(StkFloat frequency, StkFloat radius, bool normalize)
{
a_[2] = radius * radius;
a_[1] = -2.0 * radius * cos(TWO_PI * frequency / Stk::sampleRate());
a_[1] = -2.0 * radius * cos( TWO_PI * frequency / Stk::sampleRate() );
if ( normalize ) {
// Use zeros at +- 1 and normalize the filter peak gain.
@@ -85,7 +68,7 @@ void BiQuad :: setNotch(StkFloat frequency, StkFloat radius)
{
// 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());
b_[1] = (StkFloat) -2.0 * radius * cos( TWO_PI * (double) frequency / Stk::sampleRate() );
}
void BiQuad :: setEqualGainZeroes()
@@ -95,17 +78,4 @@ void BiQuad :: setEqualGainZeroes()
b_[2] = -1.0;
}
void BiQuad :: setGain(StkFloat gain)
{
Filter::setGain(gain);
}
StkFloat BiQuad :: getGain(void) const
{
return Filter::getGain();
}
StkFloat BiQuad :: lastOut(void) const
{
return Filter::lastOut();
}
} // stk namespace