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Version 4.4.0

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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
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136
include/TwoPole.h
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@@ -1,28 +1,28 @@
/***************************************************/
/*! \class TwoPole
\brief STK two-pole filter class.
This protected Filter subclass implements
a two-pole digital filter. A method is
provided for creating a resonance in the
frequency response while maintaining a nearly
constant filter gain.
by Perry R. Cook and Gary P. Scavone, 1995 - 2007.
*/
/***************************************************/
#ifndef STK_TWOPOLE_H
#define STK_TWOPOLE_H
#include "Filter.h"
class TwoPole : protected Filter
namespace stk {
/***************************************************/
/*! \class TwoPole
\brief STK two-pole filter class.
This class implements a two-pole digital filter. A method is
provided for creating a resonance in the frequency response while
maintaining a nearly constant filter gain.
by Perry R. Cook and Gary P. Scavone, 1995 - 2009.
*/
/***************************************************/
class TwoPole : public Filter
{
public:
//! Default constructor creates a second-order pass-through filter.
TwoPole();
TwoPole( void );
//! Class destructor.
~TwoPole();
@@ -30,17 +30,17 @@ class TwoPole : protected Filter
//! A function to enable/disable the automatic updating of class data when the STK sample rate changes.
void ignoreSampleRateChange( bool ignore = true ) { ignoreSampleRateChange_ = ignore; };
//! Clears the internal states of the filter.
void clear(void);
//! Set the b[0] coefficient value.
void setB0(StkFloat b0);
void setB0( StkFloat b0 ) { b_[0] = b0; };
//! Set the a[1] coefficient value.
void setA1(StkFloat a1);
void setA1( StkFloat a1 ) { a_[1] = a1; };
//! Set the a[2] coefficient value.
void setA2(StkFloat a2);
void setA2( StkFloat a2 ) { a_[2] = a2; };
//! Set all filter coefficients.
void setCoefficients( StkFloat b0, StkFloat a1, StkFloat a2, bool clearState = false );
//! Sets the filter coefficients for a resonance at \e frequency (in Hz).
/*!
@@ -58,34 +58,94 @@ class TwoPole : protected Filter
*/
void setResonance(StkFloat frequency, StkFloat radius, bool normalize = false);
//! Set the filter gain.
/*!
The gain is applied at the filter input and does not affect the
coefficient values. The default gain value is 1.0.
*/
void setGain(StkFloat gain);
//! Return the current filter gain.
StkFloat getGain(void) const;
//! Return the last computed output value.
StkFloat lastOut(void) const;
StkFloat lastOut( void ) const { return lastFrame_[0]; };
//! Input one sample to the filter and return one output.
StkFloat tick(StkFloat sample);
StkFloat tick( StkFloat input );
//! Take a channel of the StkFrames object as inputs to the filter and replace with corresponding outputs.
/*!
The \c channel argument should be zero or greater (the first
channel is specified by 0). An StkError will be thrown if the \c
channel argument is equal to or greater than the number of
channels in the StkFrames object.
The StkFrames argument reference is returned. The \c channel
argument must be less than the number of channels in the
StkFrames argument (the first channel is specified by 0).
However, range checking is only performed if _STK_DEBUG_ is
defined during compilation, in which case an out-of-range value
will trigger an StkError exception.
*/
StkFrames& tick( StkFrames& frames, unsigned int channel = 0 );
//! Take a channel of the \c iFrames object as inputs to the filter and write outputs to the \c oFrames object.
/*!
The \c iFrames object reference is returned. Each channel
argument must be less than the number of channels in the
corresponding StkFrames argument (the first channel is specified
by 0). However, range checking is only performed if _STK_DEBUG_
is defined during compilation, in which case an out-of-range value
will trigger an StkError exception.
*/
StkFrames& tick( StkFrames& iFrames, StkFrames &oFrames, unsigned int iChannel = 0, unsigned int oChannel = 0 );
protected:
virtual void sampleRateChanged( StkFloat newRate, StkFloat oldRate );
};
inline StkFloat TwoPole :: tick( StkFloat input )
{
inputs_[0] = gain_ * input;
lastFrame_[0] = b_[0] * inputs_[0] - a_[1] * outputs_[1] - a_[2] * outputs_[2];
outputs_[2] = outputs_[1];
outputs_[1] = lastFrame_[0];
return lastFrame_[0];
}
inline StkFrames& TwoPole :: tick( StkFrames& frames, unsigned int channel )
{
#if defined(_STK_DEBUG_)
if ( channel >= frames.channels() ) {
errorString_ << "TwoPole::tick(): channel and StkFrames arguments are incompatible!";
handleError( StkError::FUNCTION_ARGUMENT );
}
#endif
StkFloat *samples = &frames[channel];
unsigned int hop = frames.channels();
for ( unsigned int i=0; i<frames.frames(); i++, samples += hop ) {
inputs_[0] = gain_ * *samples;
*samples = b_[0] * inputs_[0] - a_[1] * outputs_[1] - a_[2] * outputs_[2];
outputs_[2] = outputs_[1];
outputs_[1] = *samples;
}
lastFrame_[0] = outputs_[1];
return frames;
}
inline StkFrames& TwoPole :: tick( StkFrames& iFrames, StkFrames& oFrames, unsigned int iChannel, unsigned int oChannel )
{
#if defined(_STK_DEBUG_)
if ( iChannel >= iFrames.channels() || oChannel >= oFrames.channels() ) {
errorString_ << "TwoPole::tick(): channel and StkFrames arguments are incompatible!";
handleError( StkError::FUNCTION_ARGUMENT );
}
#endif
StkFloat *iSamples = &iFrames[iChannel];
StkFloat *oSamples = &oFrames[oChannel];
unsigned int iHop = iFrames.channels(), oHop = oFrames.channels();
for ( unsigned int i=0; i<iFrames.frames(); i++, iSamples += iHop, oSamples += oHop ) {
inputs_[0] = gain_ * *iSamples;
*oSamples = b_[0] * inputs_[0] - a_[1] * outputs_[1] - a_[2] * outputs_[2];
outputs_[2] = outputs_[1];
outputs_[1] = *oSamples;
}
lastFrame_[0] = outputs_[1];
return iFrames;
}
} // stk namespace
#endif