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Version 4.4.0

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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
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104
include/PoleZero.h
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@@ -1,23 +1,24 @@
/***************************************************/
/*! \class PoleZero
\brief STK one-pole, one-zero filter class.
This protected Filter subclass implements
a one-pole, one-zero digital filter. A
method is provided for creating an allpass
filter with a given coefficient. Another
method is provided to create a DC blocking filter.
by Perry R. Cook and Gary P. Scavone, 1995 - 2007.
*/
/***************************************************/
#ifndef STK_POLEZERO_H
#define STK_POLEZERO_H
#include "Filter.h"
class PoleZero : protected Filter
namespace stk {
/***************************************************/
/*! \class PoleZero
\brief STK one-pole, one-zero filter class.
This class implements a one-pole, one-zero digital filter. A
method is provided for creating an allpass filter with a given
coefficient. Another method is provided to create a DC blocking
filter.
by Perry R. Cook and Gary P. Scavone, 1995 - 2009.
*/
/***************************************************/
class PoleZero : public Filter
{
public:
@@ -27,17 +28,17 @@ class PoleZero : protected Filter
//! Class destructor.
~PoleZero();
//! 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 b[1] coefficient value.
void setB1(StkFloat b1);
void setB1( StkFloat b1 ) { b_[1] = b1; };
//! 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 b1, StkFloat a1, bool clearState = false );
//! Set the filter for allpass behavior using \e coefficient.
/*!
@@ -45,7 +46,7 @@ class PoleZero : protected Filter
which has unity gain at all frequencies. Note that the \e
coefficient magnitude must be less than one to maintain stability.
*/
void setAllpass(StkFloat coefficient);
void setAllpass( StkFloat coefficient );
//! Create a DC blocking filter with the given pole position in the z-plane.
/*!
@@ -54,33 +55,58 @@ class PoleZero : protected Filter
close to one to minimize low-frequency attenuation.
*/
void setBlockZero(StkFloat thePole = 0.99);
//! 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 setBlockZero( StkFloat thePole = 0.99 );
//! 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 \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 );
};
inline StkFloat PoleZero :: tick( StkFloat input )
{
inputs_[0] = gain_ * input;
lastFrame_[0] = b_[0] * inputs_[0] + b_[1] * inputs_[1] - a_[1] * outputs_[1];
inputs_[1] = inputs_[0];
outputs_[1] = lastFrame_[0];
return lastFrame_[0];
}
inline StkFrames& PoleZero :: tick( StkFrames& frames, unsigned int channel )
{
#if defined(_STK_DEBUG_)
if ( channel >= frames.channels() ) {
errorString_ << "PoleZero::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] + b_[1] * inputs_[1] - a_[1] * outputs_[1];
inputs_[1] = inputs_[0];
outputs_[1] = *samples;
}
lastFrame_[0] = outputs_[1];
return frames;
}
} // stk namespace
#endif