godot/servers/audio/effects/audio_effect_limiter.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

143 lines
5.7 KiB
C++

/*************************************************************************/
/* audio_effect_limiter.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_limiter.h"
void AudioEffectLimiterInstance::process(const AudioFrame *p_src_frames, AudioFrame *p_dst_frames, int p_frame_count) {
float threshdb = base->threshold;
float ceiling = Math::db2linear(base->ceiling);
float ceildb = base->ceiling;
float makeup = Math::db2linear(ceildb - threshdb);
float sc = -base->soft_clip;
float scv = Math::db2linear(sc);
float peakdb = ceildb + 25;
float scmult = Math::abs((ceildb - sc) / (peakdb - sc));
for (int i = 0; i < p_frame_count; i++) {
float spl0 = p_src_frames[i].l;
float spl1 = p_src_frames[i].r;
spl0 = spl0 * makeup;
spl1 = spl1 * makeup;
float sign0 = (spl0 < 0.0 ? -1.0 : 1.0);
float sign1 = (spl1 < 0.0 ? -1.0 : 1.0);
float abs0 = Math::abs(spl0);
float abs1 = Math::abs(spl1);
float overdb0 = Math::linear2db(abs0) - ceildb;
float overdb1 = Math::linear2db(abs1) - ceildb;
if (abs0 > scv) {
spl0 = sign0 * (scv + Math::db2linear(overdb0 * scmult));
}
if (abs1 > scv) {
spl1 = sign1 * (scv + Math::db2linear(overdb1 * scmult));
}
spl0 = MIN(ceiling, Math::abs(spl0)) * (spl0 < 0.0 ? -1.0 : 1.0);
spl1 = MIN(ceiling, Math::abs(spl1)) * (spl1 < 0.0 ? -1.0 : 1.0);
p_dst_frames[i].l = spl0;
p_dst_frames[i].r = spl1;
}
}
Ref<AudioEffectInstance> AudioEffectLimiter::instance() {
Ref<AudioEffectLimiterInstance> ins;
ins.instance();
ins->base = Ref<AudioEffectLimiter>(this);
return ins;
}
void AudioEffectLimiter::set_threshold_db(float p_threshold) {
threshold = p_threshold;
}
float AudioEffectLimiter::get_threshold_db() const {
return threshold;
}
void AudioEffectLimiter::set_ceiling_db(float p_ceiling) {
ceiling = p_ceiling;
}
float AudioEffectLimiter::get_ceiling_db() const {
return ceiling;
}
void AudioEffectLimiter::set_soft_clip_db(float p_soft_clip) {
soft_clip = p_soft_clip;
}
float AudioEffectLimiter::get_soft_clip_db() const {
return soft_clip;
}
void AudioEffectLimiter::set_soft_clip_ratio(float p_soft_clip) {
soft_clip_ratio = p_soft_clip;
}
float AudioEffectLimiter::get_soft_clip_ratio() const {
return soft_clip_ratio;
}
void AudioEffectLimiter::_bind_methods() {
ClassDB::bind_method(D_METHOD("set_ceiling_db", "ceiling"), &AudioEffectLimiter::set_ceiling_db);
ClassDB::bind_method(D_METHOD("get_ceiling_db"), &AudioEffectLimiter::get_ceiling_db);
ClassDB::bind_method(D_METHOD("set_threshold_db", "threshold"), &AudioEffectLimiter::set_threshold_db);
ClassDB::bind_method(D_METHOD("get_threshold_db"), &AudioEffectLimiter::get_threshold_db);
ClassDB::bind_method(D_METHOD("set_soft_clip_db", "soft_clip"), &AudioEffectLimiter::set_soft_clip_db);
ClassDB::bind_method(D_METHOD("get_soft_clip_db"), &AudioEffectLimiter::get_soft_clip_db);
ClassDB::bind_method(D_METHOD("set_soft_clip_ratio", "soft_clip"), &AudioEffectLimiter::set_soft_clip_ratio);
ClassDB::bind_method(D_METHOD("get_soft_clip_ratio"), &AudioEffectLimiter::get_soft_clip_ratio);
ADD_PROPERTY(PropertyInfo(Variant::REAL, "ceiling_db", PROPERTY_HINT_RANGE, "-20,-0.1,0.1"), "set_ceiling_db", "get_ceiling_db");
ADD_PROPERTY(PropertyInfo(Variant::REAL, "threshold_db", PROPERTY_HINT_RANGE, "-30,0,0.1"), "set_threshold_db", "get_threshold_db");
ADD_PROPERTY(PropertyInfo(Variant::REAL, "soft_clip_db", PROPERTY_HINT_RANGE, "0,6,0.1"), "set_soft_clip_db", "get_soft_clip_db");
ADD_PROPERTY(PropertyInfo(Variant::REAL, "soft_clip_ratio", PROPERTY_HINT_RANGE, "3,20,0.1"), "set_soft_clip_ratio", "get_soft_clip_ratio");
}
AudioEffectLimiter::AudioEffectLimiter() {
threshold = 0;
ceiling = -0.1;
soft_clip = 2;
soft_clip_ratio = 10;
}