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Code Issues Activity

try another bs412 compressor implementation

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This commit is contained in:
KubaPro010
2025-07-08 22:56:44 +02:00
parent 52f2f61a9a
commit 69494eaac4
3 changed files with 24 additions and 27 deletions
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17
filter/bs412.c
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@@ -11,16 +11,20 @@ inline float deviation_to_dbr(float deviation) {
return 10.0f * (log2f(deviation) - LOG2_19000) * 0.30103f;
}
void init_modulation_power_measure(MPXPowerMeasurement* mpx, int sample_rate) {
void init_bs412(BS412Compressor* mpx, float target_power, float attack, float release, int sample_rate) {
mpx->sample_counter = 0;
mpx->sample = 0;
mpx->sample_rate = sample_rate;
mpx->attack = expf(-1.0f / (attack * sample_rate));
mpx->release = expf(-1.0f / (release * sample_rate));
mpx->target = target_power;
mpx->gain = 1.0f;
#ifdef BS412_DEBUG
debug_printf("Initialized MPX power measurement with sample rate: %d\n", sample_rate);
#endif
}
float measure_mpx(MPXPowerMeasurement* mpx, float deviation) {
float bs412_compress(BS412Compressor* mpx, float deviation) {
mpx->sample += deviation * deviation; // rmS
mpx->sample_counter++;
@@ -42,5 +46,12 @@ float measure_mpx(MPXPowerMeasurement* mpx, float deviation) {
mpx->sample_counter = 1;
}
return modulation_power;
float gain_target = powf(10.0f, (mpx->target - modulation_power) / 20.0f); // dB to linear
if (gain_target > mpx->gain)
mpx->gain = mpx->gain * mpx->attack + (1.0f - mpx->attack) * gain_target;
else
mpx->gain = mpx->gain * mpx->release + (1.0f - mpx->release) * gain_target;
return deviation*mpx->gain;
}