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16 lines
521 B
C
16 lines
521 B
C
#include "filters.h"
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void init_preemphasis(ResistorCapacitor *filter, float tau, float sample_rate) {
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filter->prev_sample = 0.0f;
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filter->alpha = expf(-1 / (tau*sample_rate));
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filter->gain = 1.0f / (1.0f - filter->alpha);
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}
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float apply_preemphasis(ResistorCapacitor *filter, float sample) {
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float out = (sample - filter->alpha * filter->prev_sample) * filter->gain;
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filter->prev_sample = sample;
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return out;
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}
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float hard_clip(float sample, float threshold) {
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return fmaxf(-threshold, fminf(threshold, sample));
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} |