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28 lines
615 B
C
28 lines
615 B
C
#pragma once
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#include <string.h>
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#include <stdlib.h>
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#include <math.h>
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#include "constants.h"
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#include "oscillator.h"
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typedef struct
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{
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float alpha;
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float prev_sample;
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float gain;
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} ResistorCapacitor;
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void init_preemphasis(ResistorCapacitor *filter, float tau, float sample_rate);
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float apply_preemphasis(ResistorCapacitor *filter, float sample);
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float hard_clip(float sample, float threshold);
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typedef struct
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{
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float b0, b1, b2;
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float a1, a2;
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float x1, x2;
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float y1, y2;
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} Biquad;
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void init_butterworth_lpf(Biquad *filter, float cutoff_freq, float sample_rate);
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float biquad(Biquad *filter, float input); |