godot/servers/audio/effects/audio_effect_compressor.cpp
Rémi Verschelde d95794ec8a
One Copyright Update to rule them all
As many open source projects have started doing it, we're removing the
current year from the copyright notice, so that we don't need to bump
it every year.

It seems like only the first year of publication is technically
relevant for copyright notices, and even that seems to be something
that many companies stopped listing altogether (in a version controlled
codebase, the commits are a much better source of date of publication
than a hardcoded copyright statement).

We also now list Godot Engine contributors first as we're collectively
the current maintainers of the project, and we clarify that the
"exclusive" copyright of the co-founders covers the timespan before
opensourcing (their further contributions are included as part of Godot
Engine contributors).

Also fixed "cf." Frenchism - it's meant as "refer to / see".
2023-01-05 13:25:55 +01:00

238 lines
8.5 KiB
C++

/**************************************************************************/
/* audio_effect_compressor.cpp */
/**************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/**************************************************************************/
#include "audio_effect_compressor.h"
#include "servers/audio_server.h"
void AudioEffectCompressorInstance::process(const AudioFrame *p_src_frames, AudioFrame *p_dst_frames, int p_frame_count) {
float threshold = Math::db_to_linear(base->threshold);
float sample_rate = AudioServer::get_singleton()->get_mix_rate();
float ratatcoef = exp(-1 / (0.00001f * sample_rate));
float ratrelcoef = exp(-1 / (0.5f * sample_rate));
float attime = base->attack_us / 1000000.0;
float reltime = base->release_ms / 1000.0;
float atcoef = exp(-1 / (attime * sample_rate));
float relcoef = exp(-1 / (reltime * sample_rate));
float makeup = Math::db_to_linear(base->gain);
float mix = base->mix;
float gr_meter_decay = exp(1 / (1 * sample_rate));
const AudioFrame *src = p_src_frames;
if (base->sidechain != StringName() && current_channel != -1) {
int bus = AudioServer::get_singleton()->thread_find_bus_index(base->sidechain);
if (bus >= 0) {
src = AudioServer::get_singleton()->thread_get_channel_mix_buffer(bus, current_channel);
}
}
for (int i = 0; i < p_frame_count; i++) {
AudioFrame s = src[i];
//convert to positive
s.l = Math::abs(s.l);
s.r = Math::abs(s.r);
float peak = MAX(s.l, s.r);
float overdb = 2.08136898f * Math::linear_to_db(peak / threshold);
if (overdb < 0.0) { //we only care about what goes over to compress
overdb = 0.0;
}
if (overdb - rundb > 5) { // diffeence is too large
averatio = 4;
}
if (overdb > rundb) {
rundb = overdb + atcoef * (rundb - overdb);
runratio = averatio + ratatcoef * (runratio - averatio);
} else {
rundb = overdb + relcoef * (rundb - overdb);
runratio = averatio + ratrelcoef * (runratio - averatio);
}
overdb = rundb;
averatio = runratio;
float cratio;
if (false) { //rato all-in
cratio = 12 + averatio;
} else {
cratio = base->ratio;
}
float gr = -overdb * (cratio - 1) / cratio;
float grv = Math::db_to_linear(gr);
runmax = maxover + relcoef * (runmax - maxover); // highest peak for setting att/rel decays in reltime
maxover = runmax;
if (grv < gr_meter) {
gr_meter = grv;
} else {
gr_meter *= gr_meter_decay;
if (gr_meter > 1) {
gr_meter = 1;
}
}
p_dst_frames[i] = p_src_frames[i] * grv * makeup * mix + p_src_frames[i] * (1.0 - mix);
}
}
Ref<AudioEffectInstance> AudioEffectCompressor::instantiate() {
Ref<AudioEffectCompressorInstance> ins;
ins.instantiate();
ins->base = Ref<AudioEffectCompressor>(this);
ins->rundb = 0;
ins->runratio = 0;
ins->averatio = 0;
ins->runmax = 0;
ins->maxover = 0;
ins->gr_meter = 1.0;
ins->current_channel = -1;
return ins;
}
void AudioEffectCompressor::set_threshold(float p_threshold) {
threshold = p_threshold;
}
float AudioEffectCompressor::get_threshold() const {
return threshold;
}
void AudioEffectCompressor::set_ratio(float p_ratio) {
ratio = p_ratio;
}
float AudioEffectCompressor::get_ratio() const {
return ratio;
}
void AudioEffectCompressor::set_gain(float p_gain) {
gain = p_gain;
}
float AudioEffectCompressor::get_gain() const {
return gain;
}
void AudioEffectCompressor::set_attack_us(float p_attack_us) {
attack_us = p_attack_us;
}
float AudioEffectCompressor::get_attack_us() const {
return attack_us;
}
void AudioEffectCompressor::set_release_ms(float p_release_ms) {
release_ms = p_release_ms;
}
float AudioEffectCompressor::get_release_ms() const {
return release_ms;
}
void AudioEffectCompressor::set_mix(float p_mix) {
mix = p_mix;
}
float AudioEffectCompressor::get_mix() const {
return mix;
}
void AudioEffectCompressor::set_sidechain(const StringName &p_sidechain) {
AudioServer::get_singleton()->lock();
sidechain = p_sidechain;
AudioServer::get_singleton()->unlock();
}
StringName AudioEffectCompressor::get_sidechain() const {
return sidechain;
}
void AudioEffectCompressor::_validate_property(PropertyInfo &p_property) const {
if (p_property.name == "sidechain") {
String buses = "";
for (int i = 0; i < AudioServer::get_singleton()->get_bus_count(); i++) {
buses += ",";
buses += AudioServer::get_singleton()->get_bus_name(i);
}
p_property.hint_string = buses;
}
}
void AudioEffectCompressor::_bind_methods() {
ClassDB::bind_method(D_METHOD("set_threshold", "threshold"), &AudioEffectCompressor::set_threshold);
ClassDB::bind_method(D_METHOD("get_threshold"), &AudioEffectCompressor::get_threshold);
ClassDB::bind_method(D_METHOD("set_ratio", "ratio"), &AudioEffectCompressor::set_ratio);
ClassDB::bind_method(D_METHOD("get_ratio"), &AudioEffectCompressor::get_ratio);
ClassDB::bind_method(D_METHOD("set_gain", "gain"), &AudioEffectCompressor::set_gain);
ClassDB::bind_method(D_METHOD("get_gain"), &AudioEffectCompressor::get_gain);
ClassDB::bind_method(D_METHOD("set_attack_us", "attack_us"), &AudioEffectCompressor::set_attack_us);
ClassDB::bind_method(D_METHOD("get_attack_us"), &AudioEffectCompressor::get_attack_us);
ClassDB::bind_method(D_METHOD("set_release_ms", "release_ms"), &AudioEffectCompressor::set_release_ms);
ClassDB::bind_method(D_METHOD("get_release_ms"), &AudioEffectCompressor::get_release_ms);
ClassDB::bind_method(D_METHOD("set_mix", "mix"), &AudioEffectCompressor::set_mix);
ClassDB::bind_method(D_METHOD("get_mix"), &AudioEffectCompressor::get_mix);
ClassDB::bind_method(D_METHOD("set_sidechain", "sidechain"), &AudioEffectCompressor::set_sidechain);
ClassDB::bind_method(D_METHOD("get_sidechain"), &AudioEffectCompressor::get_sidechain);
ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "threshold", PROPERTY_HINT_RANGE, "-60,0,0.1"), "set_threshold", "get_threshold");
ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "ratio", PROPERTY_HINT_RANGE, "1,48,0.1"), "set_ratio", "get_ratio");
ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "gain", PROPERTY_HINT_RANGE, "-20,20,0.1"), "set_gain", "get_gain");
ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "attack_us", PROPERTY_HINT_RANGE, U"20,2000,1,suffix:\u00B5s"), "set_attack_us", "get_attack_us");
ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "release_ms", PROPERTY_HINT_RANGE, "20,2000,1,suffix:ms"), "set_release_ms", "get_release_ms");
ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "mix", PROPERTY_HINT_RANGE, "0,1,0.01"), "set_mix", "get_mix");
ADD_PROPERTY(PropertyInfo(Variant::STRING_NAME, "sidechain", PROPERTY_HINT_ENUM), "set_sidechain", "get_sidechain");
}
AudioEffectCompressor::AudioEffectCompressor() {
threshold = 0;
ratio = 4;
gain = 0;
attack_us = 20;
release_ms = 250;
mix = 1;
}