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Code Issues Activity

actually fix bs412

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This commit is contained in:
KubaPro010
2025-07-09 08:35:36 +02:00
parent ec8c898e0c
commit f06f9056fa
1 changed files with 19 additions and 10 deletions
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29
filter/bs412.c
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@@ -27,15 +27,16 @@ void init_bs412(BS412Compressor* mpx, float mpx_deviation, float target_power, f
}
float bs412_compress(BS412Compressor* mpx, float sample) {
mpx->average += sample * sample * mpx->mpx_deviation * mpx->mpx_deviation; // rmS
mpx->average += sample * sample * mpx->mpx_deviation * mpx->mpx_deviation;
mpx->average_counter++;
float avg_deviation = sqrtf(mpx->average / mpx->average_counter); // RMs
float avg_power = mpx->average / mpx->average_counter;
float avg_deviation = sqrtf(avg_power);
float modulation_power = deviation_to_dbr(avg_deviation);
#ifdef BS412_DEBUG
if(mpx->sample_counter % mpx->sample_rate == 0) {
debug_printf("MPX power: %f dBr\n", modulation_power);
if(mpx->average_counter % mpx->sample_rate == 0) {
debug_printf("MPX power: %.2f dBr\n", modulation_power);
}
#endif
@@ -43,17 +44,25 @@ float bs412_compress(BS412Compressor* mpx, float sample) {
#ifdef BS412_DEBUG
debug_printf("Resetting MPX power measurement\n");
#endif
mpx->average = avg_deviation * avg_deviation;
mpx->average = avg_power;
mpx->average_counter = 1;
}
float gain_target = powf(10.0f, (mpx->target - modulation_power) / 20.0f); // dB to linear
if (gain_target > mpx->gain)
float gain_target = powf(10.0f, (mpx->target - modulation_power) / 20.0f);
if (gain_target > mpx->gain) {
mpx->gain = mpx->gain * mpx->attack + (1.0f - mpx->attack) * gain_target;
else
} else {
mpx->gain = mpx->gain * mpx->release + (1.0f - mpx->release) * gain_target;
}
mpx->gain = fminf(mpx->max, mpx->gain);
mpx->gain = fmaxf(0.0f, mpx->gain);
return fminf(fmaxf(sample*mpx->gain, -(dbr_to_deviation(mpx->target*1.1f)/mpx->mpx_deviation)), (dbr_to_deviation(mpx->target*1.1f)/mpx->mpx_deviation));
}
float output_sample = sample * mpx->gain;
float limit_dbr = mpx->target + 0.41f;
float limit_deviation_hz = dbr_to_deviation(limit_dbr);
float normalized_limit = limit_deviation_hz / mpx->mpx_deviation;
float final_limit = fminf(1.0f, normalized_limit);
return fmaxf(-final_limit, fminf(final_limit, output_sample));
}