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try diffrent compressor

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KubaPro010
2025-03-02 10:05:27 +01:00
parent 63651bf501
commit 896ec1c913
1 changed files with 110 additions and 181 deletions
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291
lib/filters.c
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@@ -121,7 +121,22 @@ float voltage_to_power_db(float linear) {
return 10.0f * log10f(fmaxf(linear, 1e-10f)); // Avoid log(0)
}
void init_compressor(Compressor *compressor, float threshold, float ratio, float knee, float makeup_gain, float attack, float release, float rmsTime, float sample_rate) {
static float compute_gain_reduction(float input_db, float threshold, float ratio, float knee) {
float gain_reduction = 0.0f;
if (knee > 0.0f && input_db > (threshold - knee / 2.0f) && input_db < (threshold + knee / 2.0f)) {
float knee_range = input_db - (threshold - knee / 2.0f);
float knee_factor = knee_range * knee_range / (2.0f * knee);
gain_reduction = (ratio - 1.0f) * knee_factor / ratio;
} else if (input_db > threshold) {
gain_reduction = (threshold - input_db) * (1.0f - 1.0f / ratio);
}
return gain_reduction;
}
void init_compressor(Compressor *compressor, float threshold, float ratio, float knee,
float makeup_gain, float attack, float release, float rmsTime, float sample_rate) {
compressor->threshold = threshold;
compressor->ratio = ratio;
compressor->knee = knee;
@@ -134,78 +149,54 @@ void init_compressor(Compressor *compressor, float threshold, float ratio, float
compressor->rmsTime = rmsTime;
}
float rms_compress(Compressor *compressor, float sample) {
sample *= voltage_db_to_voltage(compressor->makeup_gain);
float env;
float rmsAlpha = 1.0f - exp(-1.0f / (compressor->rmsTime * compressor->sample_rate));
compressor->rmsEnv = (1.0f - rmsAlpha) * compressor->rmsEnv + rmsAlpha * (sample * sample);
env = sqrtf(compressor->rmsEnv);
float input_db = voltage_to_voltage_db(env);
float targetBoost = 0.0f;
if(input_db < compressor->threshold) {
if(compressor->knee > 0.0f) {
float delta = compressor->threshold - input_db;
if(delta < compressor->knee / 2.0f) {
targetBoost = (1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee;
} else {
targetBoost = (1.0f - 1.0f / compressor->ratio) * delta;
}
} else {
targetBoost = (1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db);
}
} else {
targetBoost = 0.0f;
}
float coeff;
if(targetBoost > compressor->gainReduction) {
coeff = expf(-1.0f / (compressor->attack * compressor->sample_rate));
} else {
coeff = expf(-1.0f / (compressor->release * compressor->sample_rate));
}
compressor->gainReduction = coeff * compressor->gainReduction + (1.0f - coeff) * targetBoost;
float gain = voltage_db_to_voltage(compressor->gainReduction);
return (sample * gain);
}
float peak_compress(Compressor *compressor, float sample) {
float env = fabsf(sample*voltage_db_to_voltage(compressor->makeup_gain));
float input_db = voltage_to_voltage_db(env);
float targetBoost = 0.0f;
if(input_db < compressor->threshold) {
if(compressor->knee > 0.0f) {
float delta = compressor->threshold - input_db;
if(delta < compressor->knee / 2.0f) {
targetBoost = (1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee;
} else {
targetBoost = (1.0f - 1.0f / compressor->ratio) * delta;
}
} else {
targetBoost = (1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db);
}
} else {
targetBoost = 0.0f;
}
float coeff;
if(targetBoost > compressor->gainReduction) {
coeff = expf(-1.0f / (compressor->attack * compressor->sample_rate));
} else {
coeff = expf(-1.0f / (compressor->release * compressor->sample_rate));
}
compressor->gainReduction = coeff * compressor->gainReduction + (1.0f - coeff) * targetBoost;
float gain = voltage_db_to_voltage(compressor->gainReduction);
return (sample * gain);
float input_level_db = linear_to_db(fabsf(sample));
float desired_gain_reduction = compute_gain_reduction(input_level_db,
compressor->threshold,
compressor->ratio,
compressor->knee);
float attack_coef = expf(-1.0f / (compressor->sample_rate * compressor->attack));
float release_coef = expf(-1.0f / (compressor->sample_rate * compressor->release));
float coef = (fabsf(desired_gain_reduction) > fabsf(compressor->gainReduction)) ? attack_coef : release_coef;
compressor->gainReduction = desired_gain_reduction + coef * (compressor->gainReduction - desired_gain_reduction);
float gain = db_to_linear(compressor->gainReduction + compressor->makeup_gain);
return sample * gain;
}
float rms_compress(Compressor *compressor, float sample) {
float rms_coef = expf(-1.0f / (compressor->sample_rate * compressor->rmsTime));
float squared_input = sample * sample;
compressor->rmsEnv = squared_input + rms_coef * (compressor->rmsEnv - squared_input);
float input_level_db = linear_to_db(sqrtf(fmaxf(compressor->rmsEnv, 1e-9f)));
float desired_gain_reduction = compute_gain_reduction(input_level_db,
compressor->threshold,
compressor->ratio,
compressor->knee);
float attack_coef = expf(-1.0f / (compressor->sample_rate * compressor->attack));
float release_coef = expf(-1.0f / (compressor->sample_rate * compressor->release));
float coef = (fabsf(desired_gain_reduction) > fabsf(compressor->gainReduction)) ? attack_coef : release_coef;
compressor->gainReduction = desired_gain_reduction + coef * (compressor->gainReduction - desired_gain_reduction);
float gain = db_to_linear(compressor->gainReduction + compressor->makeup_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->ratio = ratio;
compressor->knee = knee;
@@ -219,117 +210,55 @@ void init_compressor_stereo(StereoCompressor *compressor, float threshold, float
compressor->rmsTime = rmsTime;
}
float rms_compress_stereo(StereoCompressor *compressor, float l, float r, float *output_r) {
l *= voltage_db_to_voltage(compressor->makeup_gain);
r *= voltage_db_to_voltage(compressor->makeup_gain);
float env_l;
float env_r;
float rmsAlpha = 1.0f - exp(-1.0f / (compressor->rmsTime * compressor->sample_rate));
compressor->rmsEnv = (1.0f - rmsAlpha) * compressor->rmsEnv + rmsAlpha * (l * l);
compressor->rmsEnv2 = (1.0f - rmsAlpha) * compressor->rmsEnv2 + rmsAlpha * (r * r);
env_l = sqrtf(compressor->rmsEnv);
env_r = sqrtf(compressor->rmsEnv2);
float input_db_l = voltage_to_voltage_db(env_l);
float input_db_r = voltage_to_voltage_db(env_r);
float targetBoost_l = 0.0f;
if(input_db_l < compressor->threshold) {
if(compressor->knee > 0.0f) {
float delta = compressor->threshold - input_db_l;
if(delta < compressor->knee / 2.0f) {
targetBoost_l = (1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee;
} else {
targetBoost_l = (1.0f - 1.0f / compressor->ratio) * delta;
}
} else {
targetBoost_l = (1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db_l);
}
} else {
targetBoost_l = 0.0f;
}
float targetBoost_r = 0.0f;
if(input_db_r < compressor->threshold) {
if(compressor->knee > 0.0f) {
float delta = compressor->threshold - input_db_r;
if(delta < compressor->knee / 2.0f) {
targetBoost_r = (1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee;
} else {
targetBoost_r = (1.0f - 1.0f / compressor->ratio) * delta;
}
} else {
targetBoost_r = (1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db_r);
}
} else {
targetBoost_r = 0.0f;
}
float shared_target_boost = (targetBoost_l > targetBoost_r) ? targetBoost_l : targetBoost_r;
float coeff;
if(shared_target_boost > compressor->gainReduction) {
coeff = expf(-1.0f / (compressor->attack * compressor->sample_rate));
} else {
coeff = expf(-1.0f / (compressor->release * compressor->sample_rate));
}
compressor->gainReduction = coeff * compressor->gainReduction + (1.0f - coeff) * shared_target_boost;
float gain = voltage_db_to_voltage(compressor->gainReduction);
*output_r = (r * gain);
return (l * gain);
}
float peak_compress_stereo(StereoCompressor *compressor, float l, float r, float *output_r) {
float env_l = fabsf(l*voltage_db_to_voltage(compressor->makeup_gain));
float env_r = fabsf(r*voltage_db_to_voltage(compressor->makeup_gain));
float input_db_l = voltage_to_voltage_db(env_l);
float input_db_r = voltage_to_voltage_db(env_r);
float targetBoost_l = 0.0f;
if(input_db_l < compressor->threshold) {
if(compressor->knee > 0.0f) {
float delta = compressor->threshold - input_db_l;
if(delta < compressor->knee / 2.0f) {
targetBoost_l = (1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee;
} else {
targetBoost_l = (1.0f - 1.0f / compressor->ratio) * delta;
}
} else {
targetBoost_l = (1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db_l);
}
} else {
targetBoost_l = 0.0f;
}
float targetBoost_r = 0.0f;
if(input_db_r < compressor->threshold) {
if(compressor->knee > 0.0f) {
float delta = compressor->threshold - input_db_r;
if(delta < compressor->knee / 2.0f) {
targetBoost_r = (1.0f - 1.0f / compressor->ratio) * (delta * delta) / compressor->knee;
} else {
targetBoost_r = (1.0f - 1.0f / compressor->ratio) * delta;
}
} else {
targetBoost_r = (1.0f - 1.0f / compressor->ratio) * (compressor->threshold - input_db_r);
}
} else {
targetBoost_r = 0.0f;
}
float shared_target_boost = (targetBoost_l > targetBoost_r) ? targetBoost_l : targetBoost_r;
float coeff;
if(shared_target_boost > compressor->gainReduction) {
coeff = expf(-1.0f / (compressor->attack * compressor->sample_rate));
} else {
coeff = expf(-1.0f / (compressor->release * compressor->sample_rate));
}
compressor->gainReduction = coeff * compressor->gainReduction + (1.0f - coeff) * shared_target_boost;
float gain = voltage_db_to_voltage(compressor->gainReduction);
*output_r = (r * gain);
return (l*gain);
float max_level = fmaxf(fabsf(l), fabsf(r));
float input_level_db = linear_to_db(max_level);
float desired_gain_reduction = compute_gain_reduction(input_level_db,
compressor->threshold,
compressor->ratio,
compressor->knee);
float attack_coef = expf(-1.0f / (compressor->sample_rate * compressor->attack));
float release_coef = expf(-1.0f / (compressor->sample_rate * compressor->release));
float coef = (fabsf(desired_gain_reduction) > fabsf(compressor->gainReduction)) ? attack_coef : release_coef;
compressor->gainReduction = desired_gain_reduction + coef * (compressor->gainReduction - desired_gain_reduction);
float gain = db_to_linear(compressor->gainReduction + compressor->makeup_gain);
*output_r = r * gain;
return l * gain;
}
float rms_compress_stereo(StereoCompressor *compressor, float l, float r, float *output_r) {
float rms_coef = expf(-1.0f / (compressor->sample_rate * compressor->rmsTime));
float squared_input1 = l * l;
float squared_input2 = r * r;
compressor->rmsEnv = squared_input1 + rms_coef * (compressor->rmsEnv - squared_input1);
compressor->rmsEnv2 = squared_input2 + rms_coef * (compressor->rmsEnv2 - squared_input2);
float max_rms = fmaxf(compressor->rmsEnv, compressor->rmsEnv2);
float input_level_db = linear_to_db(sqrtf(fmaxf(max_rms, 1e-9f)));
float desired_gain_reduction = compute_gain_reduction(input_level_db,
compressor->threshold,
compressor->ratio,
compressor->knee);
float attack_coef = expf(-1.0f / (compressor->sample_rate * compressor->attack));
float release_coef = expf(-1.0f / (compressor->sample_rate * compressor->release));
float coef = (fabsf(desired_gain_reduction) > fabsf(compressor->gainReduction)) ? attack_coef : release_coef;
compressor->gainReduction = desired_gain_reduction + coef * (compressor->gainReduction - desired_gain_reduction);
float gain = db_to_linear(compressor->gainReduction + compressor->makeup_gain);
*output_r = r * gain;
return l * gain;
}