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diffrent preemp gain

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KubaPro010
2025-03-26 19:28:38 +01:00
parent 2e36f34b4a
commit eca15c9544
1 changed files with 1 additions and 1 deletions
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2
lib/filters.c
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@@ -3,7 +3,7 @@
void init_preemphasis(ResistorCapacitor *filter, float tau, float sample_rate) { void init_preemphasis(ResistorCapacitor *filter, float tau, float sample_rate) {
filter->prev_sample = 0.0f; filter->prev_sample = 0.0f;
filter->alpha = expf(-1 / (tau*sample_rate)); filter->alpha = expf(-1 / (tau*sample_rate));
filter->gain = 1.0f / (1.0f - filter->alpha); filter->gain = 1.0f / sqrtf(1.0f + filter->alpha * filter->alpha);
} }
float apply_preemphasis(ResistorCapacitor *filter, float sample) { float apply_preemphasis(ResistorCapacitor *filter, float sample) {
float out = (sample - filter->alpha * filter->prev_sample) * filter->gain; float out = (sample - filter->alpha * filter->prev_sample) * filter->gain;