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start modularization

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This commit is contained in:
KubaPro010
2025-06-21 15:06:27 +02:00
parent 33ffcd9682
commit 16f0a53c05
18 changed files with 79 additions and 43 deletions
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37
filter/gain_control.c Normal file
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#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;
agc->rmsAlpha = expf(-1.0f / (sampleRate * 0.02f));
}
float process_agc(AGC* agc, float sidechain) {
float x2 = sidechain * sidechain;
agc->rms_buffer = agc->rmsAlpha * agc->rms_buffer + (1.0f - agc->rmsAlpha) * x2;
const float instantLevel = sqrtf(agc->rms_buffer);
const float levelAlpha = (instantLevel > agc->currentLevel) ? agc->attackCoef : agc->releaseCoef;
agc->currentLevel = levelAlpha * agc->currentLevel + (1.0f - levelAlpha) * instantLevel;
float desiredGain = agc->targetLevel / (agc->currentLevel + 1e-10f);
desiredGain = fminf(fmaxf(desiredGain, agc->minGain), agc->maxGain);
const float gainAlpha = (desiredGain > agc->currentGain) ? agc->attackCoef : agc->releaseCoef;
agc->currentGain = gainAlpha * agc->currentGain + (1.0f - gainAlpha) * desiredGain;
return agc->currentGain;
}