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23 lines
582 B
C
23 lines
582 B
C
#include "math.h"
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#include <string.h>
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#include "constants.h"
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#define FIR_PHASES 32
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#define FIR_TAPS 32
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typedef struct {
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float alpha;
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float prev_sample;
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} Emphasis;
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void init_emphasis(Emphasis *pe, float tau, float sample_rate);
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float apply_pre_emphasis(Emphasis *pe, float sample);
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typedef struct {
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float low_pass_fir[FIR_PHASES][FIR_TAPS];
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float sample_buffer[FIR_TAPS];
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int buffer_index;
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} LowPassFilter;
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void init_low_pass_filter(LowPassFilter *lp, float cutoff_frequency, float sample_rate);
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float apply_low_pass_filter(LowPassFilter *lp, float sample); |