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Code Issues Activity

agc?

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This commit is contained in:
KubaPro010
2025-04-19 13:04:07 +02:00
parent 702ee8922b
commit 4564bbf737
8 changed files with 107 additions and 45 deletions
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6
lib/bs412.h
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@@ -3,9 +3,9 @@
typedef struct
{
int i;
int sample_rate;
double sample;
int i;
int sample_rate;
double sample;
} MPXPowerMeasurement;
float dbr_to_deviation(float dbr);

2
lib/debug.h
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@@ -1,4 +1,4 @@
#pragma once
#include <stdio.h>
#define debug_printf(fmt, ...) \
printf("[%s:%d in %s] " fmt, __FILE__, __LINE__, __func__, ##__VA_ARGS__)
printf("[%s:%d in %s] " fmt, __FILE__, __LINE__, __func__, ##__VA_ARGS__)

6
lib/filters.h
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@@ -7,12 +7,6 @@
#include "optimization.h"
#include "oscillator.h"
#if USE_NEON
#define LPF_ORDER 20 // neon has to have divisable by 4
#else
#define LPF_ORDER 10
#endif
typedef struct
{
float alpha;

40
lib/gain_control.c Normal file
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@@ -0,0 +1,40 @@
#include "gain_control.h"
void initAGC(AGC* agc, int sampleRate, float targetLevel, float minGain, float maxGain, float attackTime, float releaseTime) {
agc->sampleRate = sampleRate;
agc->targetLevel = targetLevel;
agc->minGain = minGain;
agc->maxGain = maxGain;
agc->attackTime = attackTime;
agc->releaseTime = releaseTime;
agc->attackCoef = expf(-1.0f / (sampleRate * attackTime));
agc->releaseCoef = expf(-1.0f / (sampleRate * releaseTime));
agc->currentGain = 1.0f;
agc->currentLevel = 0.0f;
agc->rms_buffer = 0.0f;
}
float process_agc_stereo(AGC* agc, float left, float right, float *right_out) {
float sample = (left+right)/2;
float x2 = sample * sample;
float rmsAlpha = expf(-1.0f / (agc->sampleRate * 0.04));
agc->rms_buffer = rmsAlpha * agc->rms_buffer + (1.0f - rmsAlpha) * x2;
float instantLevel = sqrtf(agc->rms_buffer);
float alpha = (instantLevel > agc->currentLevel) ? agc->attackCoef : agc->releaseCoef;
agc->currentLevel = alpha * agc->currentLevel + (1.0f - alpha) * instantLevel;
float desiredGain = agc->targetLevel / fmaxf(agc->currentLevel, 1e-10f);
desiredGain = fminf(fmaxf(desiredGain, agc->minGain), agc->maxGain);
float gainAlpha = (desiredGain > agc->currentGain) ? agc->attackCoef : agc->releaseCoef;
agc->currentGain = gainAlpha * agc->currentGain + (1.0f - gainAlpha) * desiredGain;
*right_out = right * agc->currentGain;
return left * agc->currentGain;
}

22
lib/gain_control.h Normal file
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@@ -0,0 +1,22 @@
#pragma once
#include <math.h>
typedef struct {
float targetLevel;
float maxGain;
float minGain;
float attackTime;
float releaseTime;
float currentGain;
float currentLevel;
int sampleRate;
float attackCoef;
float releaseCoef;
float rms_buffer;
} AGC;
void initAGC(AGC* agc, int sampleRate, float targetLevel, float minGain, float maxGain, float attackTime, float releaseTime);
float process_agc_stereo(AGC* agc, float left, float right, float *right_out);

10
lib/oscillator.c
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@@ -23,15 +23,15 @@ float get_oscillator_cos_sample(Oscillator *osc) {
}
float get_oscillator_sin_multiplier_ni(Oscillator *osc, float multiplier) {
float new_phase = osc->phase * multiplier;
new_phase -= (new_phase >= M_2PI) ? M_2PI : 0.0f;
return sinf(new_phase);
float new_phase = osc->phase * multiplier;
new_phase -= (new_phase >= M_2PI) ? M_2PI : 0.0f;
return sinf(new_phase);
}
float get_oscillator_cos_multiplier_ni(Oscillator *osc, float multiplier) {
float new_phase = osc->phase * multiplier;
new_phase -= (new_phase >= M_2PI) ? M_2PI : 0.0f;
return cosf(new_phase);
new_phase -= (new_phase >= M_2PI) ? M_2PI : 0.0f;
return cosf(new_phase);
}
void advance_oscillator(Oscillator *osc) {