three.js/examples/jsm/math/ColorConverter.d.ts

import {
	Color
} from '../../../src/Three';

export interface HSL {
	h: number;
	s: number;
	l: number;
}

export interface CMYK {
	c: number;
	m: number;
	y: number;
	k: number;
}

export namespace ColorConverter {

	export function setHSV( color: Color, h: number, s: number, v: number ): Color;
	export function getHSV( color: Color, target: HSL ): HSL;
	export function setCMYK( color: Color, c: number, m: number, y: number, k: number ): Color;
	export function getCMYK( color: Color, target: CMYK ): CMYK;

}