virtualx-engine/servers/audio/effects/audio_effect_compressor.cpp
2018-03-21 22:45:30 +01:00

249 lines
8.4 KiB
C++

/*************************************************************************/
/* audio_effect_compressor.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2018 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2018 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;
}