ref: 19a991d12e072f63f39deaa24ae083d6ca417b71
dir: /LEAF/Inc/leaf-filters.h/
/*==============================================================================
leaf-filters.h
Created: 20 Jan 2017 12:01:10pm
Author: Michael R Mulshine
==============================================================================*/
#ifndef LEAF_FILTERS_H_INCLUDED
#define LEAF_FILTERS_H_INCLUDED
#ifdef __cplusplus
extern "C" {
#endif
//==============================================================================
#include "leaf-math.h"
#include "leaf-delay.h"
#include "leaf-tables.h"
//==============================================================================
/* tAllpass: Schroeder allpass. Comb-filter with feedforward and feedback. */
typedef struct _tAllpass
{
float gain;
tLinearDelay delay;
float lastOut;
} _tAllpass;
typedef _tAllpass* tAllpass;
void tAllpass_init (tAllpass* const, float initDelay, uint32_t maxDelay);
void tAllpass_free (tAllpass* const);
float tAllpass_tick (tAllpass* const, float input);
void tAllpass_setGain (tAllpass* const, float gain);
void tAllpass_setDelay (tAllpass* const f, float delay);
//==============================================================================
/* tOnePole: OnePole filter, reimplemented from STK (Cook and Scavone). */
typedef struct _tOnePole
{
float gain;
float a0,a1;
float b0,b1;
float lastIn, lastOut;
} _tOnePole;
typedef _tOnePole* tOnePole;
void tOnePole_init (tOnePole* const, float thePole);
void tOnePole_free (tOnePole* const);
float tOnePole_tick (tOnePole* const, float input);
void tOnePole_setB0 (tOnePole* const, float b0);
void tOnePole_setA1 (tOnePole* const, float a1);
void tOnePole_setPole (tOnePole* const, float thePole);
void tOnePole_setFreq (tOnePole* const, float freq);
void tOnePole_setCoefficients(tOnePole* const, float b0, float a1);
void tOnePole_setGain (tOnePole* const, float gain);
//==============================================================================
/* TwoPole filter, reimplemented from STK (Cook and Scavone). */
typedef struct _tTwoPole
{
float gain;
float a0, a1, a2;
float b0;
float radius, frequency;
oBool normalize;
float lastOut[2];
} _tTwoPole;
typedef _tTwoPole* tTwoPole;
void tTwoPole_init (tTwoPole* const);
void tTwoPole_free (tTwoPole* const);
float tTwoPole_tick (tTwoPole* const, float input);
void tTwoPole_setB0 (tTwoPole* const, float b0);
void tTwoPole_setA1 (tTwoPole* const, float a1);
void tTwoPole_setA2 (tTwoPole* const, float a2);
void tTwoPole_setResonance (tTwoPole* const, float freq, float radius, oBool normalize);
void tTwoPole_setCoefficients(tTwoPole* const, float b0, float a1, float a2);
void tTwoPole_setGain (tTwoPole* const, float gain);
//==============================================================================
/* OneZero filter, reimplemented from STK (Cook and Scavone). */
typedef struct _tOneZero
{
float gain;
float b0,b1;
float lastIn, lastOut, frequency;
} _tOneZero;
typedef _tOneZero* tOneZero;
void tOneZero_init (tOneZero* const, float theZero);
void tOneZero_free (tOneZero* const);
float tOneZero_tick (tOneZero* const, float input);
void tOneZero_setB0 (tOneZero* const, float b0);
void tOneZero_setB1 (tOneZero* const, float b1);
void tOneZero_setZero (tOneZero* const, float theZero);
void tOneZero_setCoefficients(tOneZero* const, float b0, float b1);
void tOneZero_setGain (tOneZero* const, float gain);
float tOneZero_getPhaseDelay(tOneZero *f, float frequency );
//==============================================================================
/* TwoZero filter, reimplemented from STK (Cook and Scavone). */
typedef struct _tTwoZero
{
float gain;
float b0, b1, b2;
float frequency, radius;
float lastIn[2];
} _tTwoZero;
typedef _tTwoZero* tTwoZero;
void tTwoZero_init (tTwoZero* const);
void tTwoZero_free (tTwoZero* const);
float tTwoZero_tick (tTwoZero* const, float input);
void tTwoZero_setB0 (tTwoZero* const, float b0);
void tTwoZero_setB1 (tTwoZero* const, float b1);
void tTwoZero_setB2 (tTwoZero* const, float b2);
void tTwoZero_setNotch (tTwoZero* const, float frequency, float radius);
void tTwoZero_setCoefficients(tTwoZero* const, float b0, float b1, float b2);
void tTwoZero_setGain (tTwoZero* const, float gain);
//==============================================================================
/* PoleZero filter, reimplemented from STK (Cook and Scavone). */
typedef struct _tPoleZero
{
float gain;
float a0,a1;
float b0,b1;
float lastIn, lastOut;
} _tPoleZero;
typedef _tPoleZero* tPoleZero;
void tPoleZero_init (tPoleZero* const);
void tPoleZero_free (tPoleZero* const);
float tPoleZero_tick (tPoleZero* const, float input);
void tPoleZero_setB0 (tPoleZero* const, float b0);
void tPoleZero_setB1 (tPoleZero* const, float b1);
void tPoleZero_setA1 (tPoleZero* const, float a1);
void tPoleZero_setCoefficients (tPoleZero* const, float b0, float b1, float a1);
void tPoleZero_setAllpass (tPoleZero* const, float coeff);
void tPoleZero_setBlockZero (tPoleZero* const, float thePole);
void tPoleZero_setGain (tPoleZero* const, float gain);
//==============================================================================
/* BiQuad filter, reimplemented from STK (Cook and Scavone). */
typedef struct _tBiQuad
{
float gain;
float a0, a1, a2;
float b0, b1, b2;
float lastIn[2];
float lastOut[2];
float frequency, radius;
oBool normalize;
} _tBiQuad;
typedef _tBiQuad* tBiQuad;
void tBiQuad_init (tBiQuad* const);
void tBiQuad_free (tBiQuad* const);
float tBiQuad_tick (tBiQuad* const, float input);
void tBiQuad_setB0 (tBiQuad* const, float b0);
void tBiQuad_setB1 (tBiQuad* const, float b1);
void tBiQuad_setB2 (tBiQuad* const, float b2);
void tBiQuad_setA1 (tBiQuad* const, float a1);
void tBiQuad_setA2 (tBiQuad* const, float a2);
void tBiQuad_setNotch (tBiQuad* const, float freq, float radius);
void tBiQuad_setResonance (tBiQuad* const, float freq, float radius, oBool normalize);
void tBiQuad_setCoefficients(tBiQuad* const, float b0, float b1, float b2, float a1, float a2);
void tBiQuad_setGain (tBiQuad* const, float gain);
//==============================================================================
/* State Variable Filter, algorithm from Andy Simper. */
typedef enum SVFType
{
SVFTypeHighpass = 0,
SVFTypeLowpass,
SVFTypeBandpass,
SVFTypeNotch,
SVFTypePeak,
} SVFType;
typedef struct _tSVF
{
SVFType type;
float cutoff, Q;
float ic1eq,ic2eq;
float g,k,a1,a2,a3;
} _tSVF;
typedef _tSVF* tSVF;
void tSVF_init (tSVF* const, SVFType type, float freq, float Q);
void tSVF_free (tSVF* const);
float tSVF_tick (tSVF* const, float v0);
void tSVF_setFreq (tSVF* const, float freq);
void tSVF_setQ (tSVF* const, float Q);
//==============================================================================
/* Efficient State Variable Filter for 14-bit control input, [0, 4096). */
typedef struct _tEfficientSVF
{
SVFType type;
float cutoff, Q;
float ic1eq,ic2eq;
float g,k,a1,a2,a3;
} _tEfficientSVF;
typedef _tEfficientSVF* tEfficientSVF;
void tEfficientSVF_init (tEfficientSVF* const, SVFType type, uint16_t controlFreq, float Q);
void tEfficientSVF_free (tEfficientSVF* const);
float tEfficientSVF_tick (tEfficientSVF* const, float v0);
void tEfficientSVF_setFreq (tEfficientSVF* const, uint16_t controlFreq);
void tEfficientSVF_setQ (tEfficientSVF* const, float Q);
//==============================================================================
/* Simple Highpass filter. */
typedef struct _tHighpass
{
float xs, ys, R;
float frequency;
} _tHighpass;
typedef _tHighpass* tHighpass;
void tHighpass_init (tHighpass* const, float freq);
void tHighpass_free (tHighpass* const);
float tHighpass_tick (tHighpass* const, float x);
void tHighpass_setFreq (tHighpass* const, float freq);
float tHighpass_getFreq (tHighpass* const);
//==============================================================================
// Butterworth Filter
#define NUM_SVF_BW 16
typedef struct _tButterworth
{
float gain;
int N;
tSVF low[NUM_SVF_BW];
tSVF high[NUM_SVF_BW];
float f1,f2;
} _tButterworth;
typedef _tButterworth* tButterworth;
void tButterworth_init (tButterworth* const, int N, float f1, float f2);
void tButterworth_free (tButterworth* const);
float tButterworth_tick (tButterworth* const, float input);
void tButterworth_setF1 (tButterworth* const, float in);
void tButterworth_setF2 (tButterworth* const, float in);
void tButterworth_setFreqs (tButterworth* const, float f1, float f2);
//==============================================================================
typedef struct _tFIR
{
float* past;
float* coeff;
int numTaps;
} _tFIR;
typedef _tFIR* tFIR;
void tFIR_init (tFIR* const, float* coeffs, int numTaps);
void tFIR_free (tFIR* const);
float tFIR_tick (tFIR* const, float input);
void tFIR_coeffs (tFIR* const, float in);
//==============================================================================
#ifdef __cplusplus
}
#endif
#endif // LEAF_FILTERS_H_INCLUDED
//==============================================================================