mirror of
https://github.com/Tonejs/Tone.js
synced 2024-12-30 13:33:10 +00:00
81 lines
2.4 KiB
TypeScript
81 lines
2.4 KiB
TypeScript
import { InputNode, OutputNode, ToneAudioNode, ToneAudioNodeOptions } from "../../core/context/ToneAudioNode";
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import { Decibels } from "../../core/type/Units";
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import { optionsFromArguments } from "../../core/util/Defaults";
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import { Compressor } from "./Compressor";
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import { Param } from "../../core/context/Param";
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import { readOnly } from "../../core/util/Interface";
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export interface LimiterOptions extends ToneAudioNodeOptions {
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threshold: Decibels;
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};
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/**
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* Limiter will limit the loudness of an incoming signal.
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* It is composed of a [[Compressor]] with a fast attack
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* and release and max ratio. Limiters are commonly used to safeguard against
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* signal clipping. Unlike a compressor, limiters do not provide
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* smooth gain reduction and almost completely prevent
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* additional gain above the threshold.
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*
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* @example
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* import { Limiter, Oscillator } from "tone";
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* const limiter = new Limiter(-20).toDestination();
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* const oscillator = new Oscillator().connect(limiter);
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* oscillator.start();
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*/
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export class Limiter extends ToneAudioNode<LimiterOptions> {
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readonly name: string = "Limiter";
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readonly input: InputNode;
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readonly output: OutputNode;
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/**
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* The compressor which does the limiting
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*/
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private _compressor: Compressor;
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readonly threshold: Param<"decibels">
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/**
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* @param threshold The threshold above which the gain reduction is applied.
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*/
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constructor(threshold?: Decibels);
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constructor(options?: Partial<LimiterOptions>);
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constructor() {
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super(Object.assign(optionsFromArguments(Limiter.getDefaults(), arguments, ["threshold"])));
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const options = optionsFromArguments(Limiter.getDefaults(), arguments, ["threshold"]);
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this._compressor = this.input = this.output = new Compressor({
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context: this.context,
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ratio: 20,
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attack: 0,
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release: 0,
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threshold: options.threshold
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});
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this.threshold = this._compressor.threshold;
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readOnly(this, "threshold");
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}
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static getDefaults(): LimiterOptions {
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return Object.assign(ToneAudioNode.getDefaults(), {
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threshold: -12
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});
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}
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/**
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* A read-only decibel value for metering purposes, representing the current amount of gain
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* reduction that the compressor is applying to the signal.
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*/
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get reduction(): Decibels {
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return this._compressor.reduction;
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}
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dispose(): this {
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super.dispose();
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this._compressor.dispose();
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this.threshold.dispose();
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return this;
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}
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}
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