colorjs.io/src/spaces/prophoto-linear.js

Let’s get serious about color

import RGBColorSpace from "../rgbspace.js";
import XYZ_D50 from "./xyz-d50.js";

// convert an array of  prophoto-rgb values to CIE XYZ
// using  D50 (so no chromatic adaptation needed afterwards)
// matrix cannot be expressed in rational form, but is calculated to 64 bit accuracy
// see https://github.com/w3c/csswg-drafts/issues/7675
const toXYZ_M = [
	[ 0.79776664490064230,  0.13518129740053308,  0.03134773412839220 ],
	[ 0.28807482881940130,  0.71183523424187300,  0.00008993693872564 ],
	[ 0.00000000000000000,  0.00000000000000000,  0.82510460251046020 ],
];

const fromXYZ_M = [
	[  1.34578688164715830, -0.25557208737979464, -0.05110186497554526 ],
	[ -0.54463070512490190,  1.50824774284514680,  0.02052744743642139 ],
	[  0.00000000000000000,  0.00000000000000000,  1.21196754563894520 ],
];

export default new RGBColorSpace({
	id: "prophoto-linear",
	cssId: "--prophoto-rgb-linear",
	name: "Linear ProPhoto",
	white: "D50",
	base: XYZ_D50,
	toXYZ_M,
	fromXYZ_M,
});