The Synthesis ToolKit in C++ (STK)

Home Information Classes Download Usage Mail List Requirements Links FAQ Tutorial

Fir.h
1#ifndef STK_FIR_H
2#define STK_FIR_H
3
4#include "Filter.h"
5
6namespace stk {
7
8/***************************************************/
28/***************************************************/
29
30 class Fir : public Filter
31{
32public:
34 Fir( void );
35
37
41 Fir( std::vector<StkFloat> &coefficients );
42
44 ~Fir( void );
45
47
52 void setCoefficients( std::vector<StkFloat> &coefficients, bool clearState = false );
53
55 StkFloat lastOut( void ) const { return lastFrame_[0]; };
56
58 StkFloat tick( StkFloat input );
59
61
69 StkFrames& tick( StkFrames& frames, unsigned int channel = 0 );
70
72
80 StkFrames& tick( StkFrames& iFrames, StkFrames &oFrames, unsigned int iChannel = 0, unsigned int oChannel = 0 );
81
82protected:
83
84};
85
86 inline StkFloat Fir :: tick( StkFloat input )
87{
88 lastFrame_[0] = 0.0;
89 inputs_[0] = gain_ * input;
90
91 for ( unsigned int i=(unsigned int)(b_.size())-1; i>0; i-- ) {
92 lastFrame_[0] += b_[i] * inputs_[i];
93 inputs_[i] = inputs_[i-1];
94 }
95 lastFrame_[0] += b_[0] * inputs_[0];
96
97 return lastFrame_[0];
98}
99
100 inline StkFrames& Fir :: tick( StkFrames& frames, unsigned int channel )
101{
102#if defined(_STK_DEBUG_)
103 if ( channel >= frames.channels() ) {
104 oStream_ << "Fir::tick(): channel and StkFrames arguments are incompatible!";
105 handleError( StkError::FUNCTION_ARGUMENT );
106 }
107#endif
108
109 StkFloat *samples = &frames[channel];
110 unsigned int i, hop = frames.channels();
111 for ( unsigned int j=0; j<frames.frames(); j++, samples += hop ) {
112 inputs_[0] = gain_ * *samples;
113 *samples = 0.0;
114
115 for ( i=(unsigned int)b_.size()-1; i>0; i-- ) {
116 *samples += b_[i] * inputs_[i];
117 inputs_[i] = inputs_[i-1];
118 }
119 *samples += b_[0] * inputs_[0];
120 }
121
122 lastFrame_[0] = *(samples-hop);
123 return frames;
124}
125
126 inline StkFrames& Fir :: tick( StkFrames& iFrames, StkFrames& oFrames, unsigned int iChannel, unsigned int oChannel )
127{
128#if defined(_STK_DEBUG_)
129 if ( iChannel >= iFrames.channels() || oChannel >= oFrames.channels() ) {
130 oStream_ << "Fir::tick(): channel and StkFrames arguments are incompatible!";
131 handleError( StkError::FUNCTION_ARGUMENT );
132 }
133#endif
134
135 StkFloat *iSamples = &iFrames[iChannel];
136 StkFloat *oSamples = &oFrames[oChannel];
137 unsigned int i, iHop = iFrames.channels(), oHop = oFrames.channels();
138 for ( unsigned int j=0; j<iFrames.frames(); j++, iSamples += iHop, oSamples += oHop ) {
139 inputs_[0] = gain_ * *iSamples;
140 *oSamples = 0.0;
141
142 for ( i=(unsigned int)b_.size()-1; i>0; i-- ) {
143 *oSamples += b_[i] * inputs_[i];
144 inputs_[i] = inputs_[i-1];
145 }
146 *oSamples += b_[0] * inputs_[0];
147 }
148
149 lastFrame_[0] = *(oSamples-oHop);
150 return iFrames;
151}
152
153} // stk namespace
154
155#endif
stk::Filter
STK abstract filter class.
Definition Filter.h:23
stk::Fir
STK general finite impulse response filter class.
Definition Fir.h:31
stk::Fir::lastOut
StkFloat lastOut(void) const
Return the last computed output value.
Definition Fir.h:55
stk::Fir::~Fir
~Fir(void)
Class destructor.
stk::Fir::Fir
Fir(void)
Default constructor creates a zero-order pass-through "filter".
stk::Fir::Fir
Fir(std::vector< StkFloat > &coefficients)
Overloaded constructor which takes filter coefficients.
stk::Fir::setCoefficients
void setCoefficients(std::vector< StkFloat > &coefficients, bool clearState=false)
Set filter coefficients.
stk::Fir::tick
StkFloat tick(StkFloat input)
Input one sample to the filter and return one output.
Definition Fir.h:86
stk::StkFrames
An STK class to handle vectorized audio data.
Definition Stk.h:279
stk::StkFrames::channels
unsigned int channels(void) const
Return the number of channels represented by the data.
Definition Stk.h:416
stk::StkFrames::frames
unsigned int frames(void) const
Return the number of sample frames represented by the data.
Definition Stk.h:419
stk
The STK namespace.
Definition ADSR.h:6

The Synthesis ToolKit in C++ (STK)
©1995--2023 Perry R. Cook and Gary P. Scavone. All Rights Reserved.