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try a diffrent compressor

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kuba
2025-03-02 09:41:24 +01:00
parent 48be951566
commit 801b4a0e9a
2 changed files with 50 additions and 49 deletions
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lib/filters.c
+48 -47
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@@ -129,7 +129,7 @@ void init_compressor(Compressor *compressor, float threshold, float ratio, float
compressor->attack = attack; compressor->attack = attack;
compressor->release = release; compressor->release = release;
compressor->sample_rate = sample_rate; compressor->sample_rate = sample_rate;
compressor->gainReduction = 0.0f; // now this will become negative for boost compressor->gainReduction = 0.0f;
compressor->rmsEnv = 0.0f; compressor->rmsEnv = 0.0f;
compressor->rmsTime = rmsTime; compressor->rmsTime = rmsTime;
} }
@@ -142,31 +142,31 @@ float rms_compress(Compressor *compressor, float sample) {
float input_db = voltage_to_voltage_db(env); float input_db = voltage_to_voltage_db(env);
float targetGR = 0.0f; float targetBoost = 0.0f;
if(input_db < compressor->threshold) { if(input_db < compressor->threshold) {
if(compressor->knee > 0.0f) { if(compressor->knee > 0.0f) {
float delta = compressor->threshold - input_db; // positive difference float delta = compressor->threshold - input_db;
if(delta < compressor->knee / 2.0f) { if(delta < compressor->knee / 2.0f) {
targetGR = -(1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee; targetBoost = (1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee;
} else { } else {
targetGR = -(1.0f - 1.0f / compressor->ratio) * delta; targetBoost = (1.0f - 1.0f / compressor->ratio) * delta;
} }
} else { } else {
targetGR = -(1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db); targetBoost = (1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db);
} }
} else { } else {
targetGR = 0.0f; targetBoost = 0.0f;
} }
float coeff; float coeff;
if(targetGR < compressor->gainReduction) { if(targetBoost > compressor->gainReduction) {
coeff = expf(-1.0f / (compressor->attack * compressor->sample_rate)); coeff = expf(-1.0f / (compressor->attack * compressor->sample_rate));
} else { } else {
coeff = expf(-1.0f / (compressor->release * compressor->sample_rate)); coeff = expf(-1.0f / (compressor->release * compressor->sample_rate));
} }
compressor->gainReduction = coeff * compressor->gainReduction + (1.0f - coeff) * targetGR; compressor->gainReduction = coeff * compressor->gainReduction + (1.0f - coeff) * targetBoost;
float gain = voltage_db_to_voltage(compressor->makeup_gain - compressor->gainReduction); float gain = voltage_db_to_voltage(compressor->makeup_gain + compressor->gainReduction);
return sample * gain; return sample * gain;
} }
@@ -174,34 +174,35 @@ float peak_compress(Compressor *compressor, float sample) {
float env = fabsf(sample); float env = fabsf(sample);
float input_db = voltage_to_voltage_db(env); float input_db = voltage_to_voltage_db(env);
float targetGR = 0.0f; float targetBoost = 0.0f;
if(input_db < compressor->threshold) { if(input_db < compressor->threshold) {
if(compressor->knee > 0.0f) { if(compressor->knee > 0.0f) {
float delta = compressor->threshold - input_db; float delta = compressor->threshold - input_db;
if(delta < compressor->knee / 2.0f) { if(delta < compressor->knee / 2.0f) {
targetGR = -(1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee; targetBoost = (1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee;
} else { } else {
targetGR = -(1.0f - 1.0f / compressor->ratio) * delta; targetBoost = (1.0f - 1.0f / compressor->ratio) * delta;
} }
} else { } else {
targetGR = -(1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db); targetBoost = (1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db);
} }
} else { } else {
targetGR = 0.0f; targetBoost = 0.0f;
} }
float coeff; float coeff;
if(targetGR < compressor->gainReduction) { if(targetBoost > compressor->gainReduction) {
coeff = expf(-1.0f / (compressor->attack * compressor->sample_rate)); coeff = expf(-1.0f / (compressor->attack * compressor->sample_rate));
} else { } else {
coeff = expf(-1.0f / (compressor->release * compressor->sample_rate)); coeff = expf(-1.0f / (compressor->release * compressor->sample_rate));
} }
compressor->gainReduction = coeff * compressor->gainReduction + (1.0f - coeff) * targetGR; compressor->gainReduction = coeff * compressor->gainReduction + (1.0f - coeff) * targetBoost;
float gain = voltage_db_to_voltage(compressor->makeup_gain - compressor->gainReduction); float gain = voltage_db_to_voltage(compressor->makeup_gain + compressor->gainReduction);
return sample * gain; return sample * gain;
} }
void init_compressor_stereo(StereoCompressor *compressor, float threshold, float ratio, float knee, float makeup_gain, float attack, float release, float rmsTime, float sample_rate) { void init_compressor_stereo(StereoCompressor *compressor, float threshold, float ratio, float knee, float makeup_gain, float attack, float release, float rmsTime, float sample_rate) {
compressor->threshold = threshold; compressor->threshold = threshold;
compressor->ratio = ratio; compressor->ratio = ratio;
@@ -219,7 +220,7 @@ void init_compressor_stereo(StereoCompressor *compressor, float threshold, float
float rms_compress_stereo(StereoCompressor *compressor, float l, float r, float *output_r) { float rms_compress_stereo(StereoCompressor *compressor, float l, float r, float *output_r) {
float env_l, env_r; float env_l, env_r;
float rmsAlpha = 1.0f - exp(-1.0f / (compressor->rmsTime * compressor->sample_rate)); float rmsAlpha = 1.0f - exp(-1.0f / (compressor->rmsTime * compressor->sample_rate));
compressor->rmsEnv = (1.0f - rmsAlpha) * compressor->rmsEnv + rmsAlpha * (l * l); compressor->rmsEnv = (1.0f - rmsAlpha) * compressor->rmsEnv + rmsAlpha * (l * l);
compressor->rmsEnv2 = (1.0f - rmsAlpha) * compressor->rmsEnv2 + rmsAlpha * (r * r); compressor->rmsEnv2 = (1.0f - rmsAlpha) * compressor->rmsEnv2 + rmsAlpha * (r * r);
env_l = sqrtf(compressor->rmsEnv); env_l = sqrtf(compressor->rmsEnv);
env_r = sqrtf(compressor->rmsEnv2); env_r = sqrtf(compressor->rmsEnv2);
@@ -227,49 +228,49 @@ float rms_compress_stereo(StereoCompressor *compressor, float l, float r, float
float input_db_l = voltage_to_voltage_db(env_l); float input_db_l = voltage_to_voltage_db(env_l);
float input_db_r = voltage_to_voltage_db(env_r); float input_db_r = voltage_to_voltage_db(env_r);
float targetGR_l = 0.0f; float targetBoost_l = 0.0f;
if(input_db_l < compressor->threshold) { if(input_db_l < compressor->threshold) {
if(compressor->knee > 0.0f) { if(compressor->knee > 0.0f) {
float delta = compressor->threshold - input_db_l; float delta = compressor->threshold - input_db_l;
if(delta < compressor->knee / 2.0f) { if(delta < compressor->knee / 2.0f) {
targetGR_l = -(1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee; targetBoost_l = (1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee;
} else { } else {
targetGR_l = -(1.0f - 1.0f / compressor->ratio) * delta; targetBoost_l = (1.0f - 1.0f / compressor->ratio) * delta;
} }
} else { } else {
targetGR_l = -(1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db_l); targetBoost_l = (1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db_l);
} }
} else { } else {
targetGR_l = 0.0f; targetBoost_l = 0.0f;
} }
float targetGR_r = 0.0f; float targetBoost_r = 0.0f;
if(input_db_r < compressor->threshold) { if(input_db_r < compressor->threshold) {
if(compressor->knee > 0.0f) { if(compressor->knee > 0.0f) {
float delta = compressor->threshold - input_db_r; float delta = compressor->threshold - input_db_r;
if(delta < compressor->knee / 2.0f) { if(delta < compressor->knee / 2.0f) {
targetGR_r = -(1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee; targetBoost_r = (1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee;
} else { } else {
targetGR_r = -(1.0f - 1.0f / compressor->ratio) * delta; targetBoost_r = (1.0f - 1.0f / compressor->ratio) * delta;
} }
} else { } else {
targetGR_r = -(1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db_r); targetBoost_r = (1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db_r);
} }
} else { } else {
targetGR_r = 0.0f; targetBoost_r = 0.0f;
} }
float shared_target_gr = (targetGR_l < targetGR_r) ? targetGR_l : targetGR_r; float shared_target_boost = (targetBoost_l > targetBoost_r) ? targetBoost_l : targetBoost_r;
float coeff; float coeff;
if(shared_target_gr < compressor->gainReduction) { if(shared_target_boost > compressor->gainReduction) {
coeff = expf(-1.0f / (compressor->attack * compressor->sample_rate)); coeff = expf(-1.0f / (compressor->attack * compressor->sample_rate));
} else { } else {
coeff = expf(-1.0f / (compressor->release * compressor->sample_rate)); coeff = expf(-1.0f / (compressor->release * compressor->sample_rate));
} }
compressor->gainReduction = coeff * compressor->gainReduction + (1.0f - coeff) * shared_target_gr; compressor->gainReduction = coeff * compressor->gainReduction + (1.0f - coeff) * shared_target_boost;
float gain = voltage_db_to_voltage(compressor->makeup_gain - compressor->gainReduction); float gain = voltage_db_to_voltage(compressor->makeup_gain + compressor->gainReduction);
*output_r = r * gain; *output_r = r * gain;
return l * gain; return l * gain;
} }
@@ -281,49 +282,49 @@ float peak_compress_stereo(StereoCompressor *compressor, float l, float r, float
float input_db_l = voltage_to_voltage_db(env_l); float input_db_l = voltage_to_voltage_db(env_l);
float input_db_r = voltage_to_voltage_db(env_r); float input_db_r = voltage_to_voltage_db(env_r);
float targetGR_l = 0.0f; float targetBoost_l = 0.0f;
if(input_db_l < compressor->threshold) { if(input_db_l < compressor->threshold) {
if(compressor->knee > 0.0f) { if(compressor->knee > 0.0f) {
float delta = compressor->threshold - input_db_l; float delta = compressor->threshold - input_db_l;
if(delta < compressor->knee / 2.0f) { if(delta < compressor->knee / 2.0f) {
targetGR_l = -(1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee; targetBoost_l = (1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee;
} else { } else {
targetGR_l = -(1.0f - 1.0f / compressor->ratio) * delta; targetBoost_l = (1.0f - 1.0f / compressor->ratio) * delta;
} }
} else { } else {
targetGR_l = -(1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db_l); targetBoost_l = (1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db_l);
} }
} else { } else {
targetGR_l = 0.0f; targetBoost_l = 0.0f;
} }
float targetGR_r = 0.0f; float targetBoost_r = 0.0f;
if(input_db_r < compressor->threshold) { if(input_db_r < compressor->threshold) {
if(compressor->knee > 0.0f) { if(compressor->knee > 0.0f) {
float delta = compressor->threshold - input_db_r; float delta = compressor->threshold - input_db_r;
if(delta < compressor->knee / 2.0f) { if(delta < compressor->knee / 2.0f) {
targetGR_r = -(1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee; targetBoost_r = (1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee;
} else { } else {
targetGR_r = -(1.0f - 1.0f / compressor->ratio) * delta; targetBoost_r = (1.0f - 1.0f / compressor->ratio) * delta;
} }
} else { } else {
targetGR_r = -(1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db_r); targetBoost_r = (1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db_r);
} }
} else { } else {
targetGR_r = 0.0f; targetBoost_r = 0.0f;
} }
float shared_target_gr = (targetGR_l < targetGR_r) ? targetGR_l : targetGR_r; float shared_target_boost = (targetBoost_l > targetBoost_r) ? targetBoost_l : targetBoost_r;
float coeff; float coeff;
if(shared_target_gr < compressor->gainReduction) { if(shared_target_boost > compressor->gainReduction) {
coeff = expf(-1.0f / (compressor->attack * compressor->sample_rate)); coeff = expf(-1.0f / (compressor->attack * compressor->sample_rate));
} else { } else {
coeff = expf(-1.0f / (compressor->release * compressor->sample_rate)); coeff = expf(-1.0f / (compressor->release * compressor->sample_rate));
} }
compressor->gainReduction = coeff * compressor->gainReduction + (1.0f - coeff) * shared_target_gr; compressor->gainReduction = coeff * compressor->gainReduction + (1.0f - coeff) * shared_target_boost;
float gain = voltage_db_to_voltage(compressor->makeup_gain - compressor->gainReduction); float gain = voltage_db_to_voltage(compressor->makeup_gain + compressor->gainReduction);
*output_r = r * gain; *output_r = r * gain;
return l * gain; return l * gain;
} }
src/fm95.c
+1 -1
View File
@@ -377,7 +377,7 @@ int main(int argc, char **argv) {
StereoCompressor comp; StereoCompressor comp;
// THRESH RATIO KNE MAKE ATT REL RMS // THRESH RATIO KNE MAKE ATT REL RMS
init_compressor_stereo(&comp, -2.0f, 8.0f, 2.0f, 12.0f, 0.025f, 0.4f, 0.04f, SAMPLE_RATE); init_compressor_stereo(&comp, -2.0f, 8.0f, 2.0f, 3.0f, 0.025f, 0.4f, 0.04f, SAMPLE_RATE);
// #endregion // #endregion
signal(SIGINT, stop); signal(SIGINT, stop);