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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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138
include/OnePole.h
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@@ -1,43 +1,40 @@
/***************************************************/
/*! \class OnePole
\brief STK one-pole filter class.
This protected Filter subclass implements
a one-pole digital filter. A method is
provided for setting the pole position along
the real axis of the z-plane while maintaining
a constant peak filter gain.
by Perry R. Cook and Gary P. Scavone, 1995 - 2007.
*/
/***************************************************/
#ifndef STK_ONEPOLE_H
#define STK_ONEPOLE_H
#include "Filter.h"
class OnePole : protected Filter
namespace stk {
/***************************************************/
/*! \class OnePole
\brief STK one-pole filter class.
This class implements a one-pole digital filter. A method is
provided for setting the pole position along the real axis of the
z-plane while maintaining a constant peak filter gain.
by Perry R. Cook and Gary P. Scavone, 1995 - 2009.
*/
/***************************************************/
class OnePole : public Filter
{
public:
//! Default constructor creates a first-order low-pass filter.
OnePole();
//! Overloaded constructor which sets the pole position during instantiation.
OnePole( StkFloat thePole );
//! The default constructor creates a low-pass filter (pole at z = 0.9).
OnePole( StkFloat thePole = 0.9 );
//! Class destructor.
~OnePole();
//! Clears the internal state 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 all filter coefficients.
void setCoefficients( StkFloat b0, StkFloat a1, bool clearState = false );
//! Set the pole position in the z-plane.
/*!
@@ -47,33 +44,90 @@ public:
pole value produces a high-pass filter. This method does not
affect the filter \e gain value.
*/
void setPole(StkFloat thePole);
//! 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;
void setPole( StkFloat thePole );
//! 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 );
};
inline StkFloat OnePole :: tick( StkFloat input )
{
inputs_[0] = gain_ * input;
lastFrame_[0] = b_[0] * inputs_[0] - a_[1] * outputs_[1];
outputs_[1] = lastFrame_[0];
return lastFrame_[0];
}
inline StkFrames& OnePole :: tick( StkFrames& frames, unsigned int channel )
{
#if defined(_STK_DEBUG_)
if ( channel >= frames.channels() ) {
errorString_ << "OnePole::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];
outputs_[1] = *samples;
}
lastFrame_[0] = outputs_[1];
return frames;
}
inline StkFrames& OnePole :: tick( StkFrames& iFrames, StkFrames& oFrames, unsigned int iChannel, unsigned int oChannel )
{
#if defined(_STK_DEBUG_)
if ( iChannel >= iFrames.channels() || oChannel >= oFrames.channels() ) {
errorString_ << "OnePole::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];
outputs_[1] = *oSamples;
}
lastFrame_[0] = outputs_[1];
return iFrames;
}
} // stk namespace
#endif