/*************************************************************************/ /* 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::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, "20,2000,1"), "set_attack_us", "get_attack_us"); ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "release_ms", PROPERTY_HINT_RANGE, "20,2000,1"), "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; }