godot/servers/audio/effects/audio_effect_compressor.cpp
Rémi Verschelde a7f49ac9a1 Update copyright statements to 2020
Happy new year to the wonderful Godot community!

We're starting a new decade with a well-established, non-profit, free
and open source game engine, and tons of further improvements in the
pipeline from hundreds of contributors.

Godot will keep getting better, and we're looking forward to all the
games that the community will keep developing and releasing with it.
2020-01-01 11:16:22 +01:00

250 lines
8.4 KiB
C++

/*************************************************************************/
/* audio_effect_compressor.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2020 Godot Engine contributors (cf. AUTHORS.md). */
/* */
/* 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::db2linear(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::db2linear(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::linear2db(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::db2linear(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::instance() {
Ref<AudioEffectCompressorInstance> ins;
ins.instance();
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 &property) const {
if (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);
}
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::REAL, "threshold", PROPERTY_HINT_RANGE, "-60,0,0.1"), "set_threshold", "get_threshold");
ADD_PROPERTY(PropertyInfo(Variant::REAL, "ratio", PROPERTY_HINT_RANGE, "1,48,0.1"), "set_ratio", "get_ratio");
ADD_PROPERTY(PropertyInfo(Variant::REAL, "gain", PROPERTY_HINT_RANGE, "-20,20,0.1"), "set_gain", "get_gain");
ADD_PROPERTY(PropertyInfo(Variant::REAL, "attack_us", PROPERTY_HINT_RANGE, "20,2000,1"), "set_attack_us", "get_attack_us");
ADD_PROPERTY(PropertyInfo(Variant::REAL, "release_ms", PROPERTY_HINT_RANGE, "20,2000,1"), "set_release_ms", "get_release_ms");
ADD_PROPERTY(PropertyInfo(Variant::REAL, "mix", PROPERTY_HINT_RANGE, "0,1,0.01"), "set_mix", "get_mix");
ADD_PROPERTY(PropertyInfo(Variant::STRING, "sidechain", PROPERTY_HINT_ENUM), "set_sidechain", "get_sidechain");
}
AudioEffectCompressor::AudioEffectCompressor() {
threshold = 0;
ratio = 4;
gain = 0;
attack_us = 20;
release_ms = 250;
mix = 1;
}