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remove limiter

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This commit is contained in:
KubaPro010
2025-12-31 10:52:19 +01:00
parent d3c39c4827
commit 48a30c89af
1 changed files with 3 additions and 15 deletions
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18
filter/bs412.c
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@@ -1,8 +1,8 @@
#include "bs412.h" #include "bs412.h"
inline float dbr_to_deviation(float dbr) { // inline float dbr_to_deviation(float dbr) {
return 19000.0f * sqrtf(pow(10.0, dbr / 10.0)); // return 19000.0f * sqrtf(pow(10.0, dbr / 10.0));
} // }
inline float deviation_to_dbr(float deviation) { inline float deviation_to_dbr(float deviation) {
if (deviation < 1e-6f) return -100.0f; if (deviation < 1e-6f) return -100.0f;
@@ -26,15 +26,6 @@ void init_bs412(BS412Compressor* mpx, uint32_t mpx_deviation, float target_power
#endif #endif
} }
static inline float soft_clip_tanh(float sample, float threshold) {
if (fabsf(sample) <= threshold) {
return sample; // Linear region
}
float sign = (sample >= 0) ? 1.0f : -1.0f;
float excess = fabsf(sample) - threshold;
return sign * (threshold + tanhf(excess) * (1.0f - threshold));
}
float bs412_compress(BS412Compressor* mpx, float sample) { float bs412_compress(BS412Compressor* mpx, float sample) {
mpx->avg_power += mpx->alpha * ((sample * sample * mpx->mpx_deviation * mpx->mpx_deviation) - mpx->avg_power); mpx->avg_power += mpx->alpha * ((sample * sample * mpx->mpx_deviation * mpx->mpx_deviation) - mpx->avg_power);
@@ -83,9 +74,6 @@ float bs412_compress(BS412Compressor* mpx, float sample) {
mpx->gain = fmaxf(0.0f, fminf(mpx->max, mpx->gain)); mpx->gain = fmaxf(0.0f, fminf(mpx->max, mpx->gain));
float output_sample = sample * mpx->gain; float output_sample = sample * mpx->gain;
float limit_threshold = dbr_to_deviation(mpx->target + 0.1f) / mpx->mpx_deviation;
output_sample = soft_clip_tanh(output_sample, limit_threshold);
if(deviation_to_dbr(avg_deviation * mpx->gain) > mpx->target && deviation_to_dbr(avg_deviation) < mpx->target) { if(deviation_to_dbr(avg_deviation * mpx->gain) > mpx->target && deviation_to_dbr(avg_deviation) < mpx->target) {
// Gain is too much, reduce // Gain is too much, reduce
float overshoot_dbr = deviation_to_dbr(avg_deviation * mpx->gain) - mpx->target; float overshoot_dbr = deviation_to_dbr(avg_deviation * mpx->gain) - mpx->target;