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nug fixes and small tweaks

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KubaPro010
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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6
lib/constants.h
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@@ -1,6 +1,6 @@
#ifndef PI
#define PI 3.14159265358979323846
#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif
#ifndef M_2PI
#define M_2PI (3.14159265358979323846 * 2.0)
#define M_2PI (M_PI * 2.0)
#endif

13
lib/filters.c
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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;
}

1
lib/fm_modulator.c
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@@ -8,6 +8,7 @@ void init_fm_modulator(FMModulator *fm, float frequency, float deviation, float
float modulate_fm(FMModulator *fm, float sample) {
float inst_freq = fm->frequency+(sample*fm->deviation);
if (inst_freq < 0.0f) inst_freq = 0.0f;
change_oscillator_frequency(&fm->osc, inst_freq);
return get_oscillator_sin_sample(&fm->osc);
}

2
lib/hilbert.c
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@@ -6,7 +6,7 @@ void compute_hilbert_coeffs(float* coeffs, int taps) {
if ((i - mid) % 2 == 0) {
coeffs[i] = 0.0f;
} else {
coeffs[i] = 2.0f / (PI * (i - mid));
coeffs[i] = 2.0f / (M_PI * (i - mid));
}
}
}

16
lib/oscillator.c
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@@ -12,25 +12,23 @@ void change_oscillator_frequency(Oscillator *osc, float frequency) {
float get_oscillator_sin_sample(Oscillator *osc) {
float sample = sinf(osc->phase);
osc->phase += osc->phase_increment;
if (osc->phase >= M_2PI) {
osc->phase -= M_2PI;
}
advance_oscillator(osc);
return sample;
}
float get_oscillator_cos_sample(Oscillator *osc) {
float sample = cosf(osc->phase);
osc->phase += osc->phase_increment;
if (osc->phase >= M_2PI) {
osc->phase -= M_2PI;
}
advance_oscillator(osc);
return sample;
}
float get_oscillator_sin_multiplier_ni(Oscillator *osc, float multiplier) {
float get_oscillator_sin_multiplier_ni(Oscillator *osc, float multiplier) { // ni = No Increment
return sinf(osc->phase*multiplier);
}
float get_oscillator_cos_multiplier_ni(Oscillator *osc, float multiplier) {
return cosf(osc->phase*multiplier);
}
void advance_oscillator(Oscillator *osc) {
osc->phase = fmodf(osc->phase + osc->phase_increment, M_2PI);
}

3
lib/oscillator.h
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@@ -14,4 +14,5 @@ void change_oscillator_frequency(Oscillator *osc, float frequency);
float get_oscillator_sin_sample(Oscillator *osc);
float get_oscillator_cos_sample(Oscillator *osc);
float get_oscillator_sin_multiplier_ni(Oscillator *osc, float multiplier);
float get_oscillator_cos_multiplier_ni(Oscillator *osc, float multiplier);
float get_oscillator_cos_multiplier_ni(Oscillator *osc, float multiplier);
void advance_oscillator(Oscillator *osc);