tone/Tone/component/analysis/Waveform.ts

A Web Audio framework for making interactive music in the browser.

import { PowerOfTwo } from "../../core/type/Units.js";
import { optionsFromArguments } from "../../core/util/Defaults.js";
import { MeterBase, MeterBaseOptions } from "./MeterBase.js";

export interface WaveformOptions extends MeterBaseOptions {
	/**
	 * The size of the Waveform. Value must be a power of two in the range 16 to 16384.
	 */
	size: PowerOfTwo;
}

/**
 * Get the current waveform data of the connected audio source.
 * @category Component
 */
export class Waveform extends MeterBase<WaveformOptions> {
	readonly name: string = "Waveform";

	/**
	 * @param size The size of the Waveform. Value must be a power of two in the range 16 to 16384.
	 */
	constructor(size?: PowerOfTwo);
	constructor(options?: Partial<WaveformOptions>);
	constructor() {
		const options = optionsFromArguments(
			Waveform.getDefaults(),
			arguments,
			["size"]
		);
		super(options);

		this._analyser.type = "waveform";
		this.size = options.size;
	}

	static getDefaults(): WaveformOptions {
		return Object.assign(MeterBase.getDefaults(), {
			size: 1024,
		});
	}

	/**
	 * Return the waveform for the current time as a Float32Array where each value in the array
	 * represents a sample in the waveform.
	 */
	getValue(): Float32Array {
		return this._analyser.getValue() as Float32Array;
	}

	/**
	 * The size of analysis. This must be a power of two in the range 16 to 16384.
	 * Determines the size of the array returned by {@link getValue}.
	 */
	get size(): PowerOfTwo {
		return this._analyser.size;
	}
	set size(size) {
		this._analyser.size = size;
	}
}