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nug fixes and small tweaks

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kuba
2025-01-29 14:49:12 +01:00
parent 76580ac4d7
commit 09b30852ab
8 changed files with 53 additions and 55 deletions
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lib/filters.c
+7 -6
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@@ -25,11 +25,11 @@ void init_lpf(FrequencyFilter* filter, float cutoffFreq, float sampleRate) {
float m = n - (FILTER_TAPS - 1.0f) / 2.0f;
// Sinc function
float sinc = (m == 0) ? 1.0f : sinf(PI * m * fc) / (PI * m);
float sinc = (m == 0) ? 1.0f : sinf(M_PI * m * fc) / (M_PI * m);
// Blackman window
float window = 0.42f - 0.5f * cosf(2.0f * PI * n / (FILTER_TAPS - 1))
+ 0.08f * cosf(4.0f * PI * n / (FILTER_TAPS - 1));
float window = 0.42f - 0.5f * cosf(2.0f * M_PI * n / (FILTER_TAPS - 1))
+ 0.08f * cosf(4.0f * M_PI * n / (FILTER_TAPS - 1));
filter->coeffs[n] = sinc * window;
}
@@ -53,11 +53,11 @@ void init_hpf(FrequencyFilter* filter, float cutoffFreq, float sampleRate) {
float m = n - (FILTER_TAPS - 1.0f) / 2.0f;
// Sinc function
float sinc = (m == 0) ? -1.0f : sinf(PI * m * fc) / (PI * m);
float sinc = (m == 0) ? 1.0f : -sinf(M_PI * m * fc) / (M_PI * m);
// Blackman window
float window = 0.42f - 0.5f * cosf(2.0f * PI * n / (FILTER_TAPS - 1))
+ 0.08f * cosf(4.0f * PI * n / (FILTER_TAPS - 1));
float window = 0.42f - 0.5f * cosf(2.0f * M_PI * n / (FILTER_TAPS - 1))
+ 0.08f * cosf(4.0f * M_PI * n / (FILTER_TAPS - 1));
filter->coeffs[n] = sinc * window;
}
@@ -148,4 +148,5 @@ float delay_line(DelayLine *delay_line, float in) {
void exit_delay_line(DelayLine *delay_line) {
free(delay_line->buffer);
delay_line->buffer = NULL;
}