colorimetry-ts

A type-safe color science library, written for Javascript.

Installation

npm install colorimetry-ts

Then import as an ES module:

import { color } from "colorimetry-ts";

Features

• Value conversions between most widely-used color spaces
  • Supports custom RGB (and non-RGB) color spaces
• Object definitions for common color gamut primaries and illuminants
• Function definitions for common tone response transfer functions
• Color differences
  • Includes CIE2000, ITP , CIE1976 (TODO), u′v′
  • Supports luminance component compensation
• Color gamut mapping
• Correlated color temperature
• Chromatic adaptation transforms
• ...and more

Examples

• Convert sRGB red primary to display-p3 RGB encoding (using 8 bits):

const srgbRed = color("srgb", [255, 0, 0], { bitDepth: 8 });
const srgbRedInP3 = srgbRed.toSpace("display-p3", { bitDepth: 8 });

console.log(srgbRedInP3.values);
// output: [ 234, 51, 35 ]

_{The input/output of RGB values are normalized between 0–1 if no bitDepth value is passed to the color's context object argument.}

• Create an XYZ color space converter to convert multiple colors:

const toXyz = color("xyz");

const color1 = color("srgb", [1, 1, 1]);
const color2 = color("display-p3", [1, 1, 1]);
const color3 = color("lab", [100, 0, 0]);

console.log(toXyz(color1).values, toXyz(color2).values, toXyz(color3).values);
// output: [ 76.036, 80.000, 87.125 ],
//         [ 76.036, 80.000, 87.125 ],
//         [ 95.046, 100.00, 108.91 ]

• Check if two colors are equal/indistinguishable from each other:

// srgb and p3 share the same blue primary
// ...but their luminance is not equal!
const colorA = color("srgb", [0, 0, 1]);
const colorB = color("display-p3", [0, 0, 1]);

console.log(colorA.equals(colorB));
// output: false

// conversions should always be equal
console.log(srgbRed.equals(srgbRedInP3));
// output: true

Note: Color value conversions using color() require absolute color spaces for both source and destination spaces, as Color object values are supposed to be non-ambiguous. For agnostic conversions, import the relevant function, e.g. ycbcrFromRgb().

Roadmap

• Possibly support BigInt to avoid floating-point errors, for use in reference conversion values