@4bitlabs/color-space

Utility functions for parsing, converting and mixing colors in sRGB, CIE-XYZ, CIE-L*a*b*, and okLab color spaces

Installing

$ npm install --save @4bitlabs/color-space

Quick-start

import { sRGB, XYZ, Lab, okLab, linearRGB } from '@4bitlabs/color-space';

const srgbColor = sRGB.create(255, 128, 0);
const xyzColor = XYZ.create(50.39, 57.009, 86.941);
const labColor = Lab.create(50.593, -49.586, 45.015);
const oklabColor = okLab.create(0.8, 0.144, 0.083);
const linearRGBColor = linearRGB.create(0.5, 0.5, 0.5);

You can also import only the specific color-spaces you intend to work by using package exports:

import * as sRGB from '@4bitlabs/color-spaces/srgb';
import * as XYZ from '@4bitlabs/color-spaces/xyz';

const tomato = sRGB.fromHex('#ff6347');
const xyzTomato = sRGB.toXYZ(tomato);
const xyzString = XYZ.toString(xyzTomato);

The following package exports are available:

| Color-Space | Import | | ----------------------------------------------------------------- | --------------------------------------------------------------- | | sRGB | import * as sRGB from "@4bitlabs/color-space/srgb" | | CIE-XYZ | import * as XYZ from "@4bitlabs/color-space/xyz" | | CIE-L*a*b* | import * as CIELab from "@4bitlabs/color-space/lab" | | OKlab | import * as okLab from "@4bitlabs/color-space/oklab" | | linear RGB | import * as linearRGB from "@4bitlabs/color-space/linear-rgb" |

sRGB colors

import {
  fromHex,
  fromUint24,
  mix,
  toHex,
  toString,
  type sRGBTuple,
} from '@4bitlabs/color-space/srgb';

// Parse from hex code
const color1: sRGBTuple = fromHex('#ff6347');

// Parse from a uint24 in 0xBBGGRR byte order.
const color2: sRGBTuple = fromUint24(0xed9564);

// Mix color 1 and color 2 at 50% in sRGB color-space.
const color3: sRGBTuple = mix(color1, color2, 0.5);

console.log(toHex(color3)); // "#b17c9a"
console.log(toString(color3)); // "rgb(177 124 154)"

CIE-XYZ colors

import {
  create,
  mix,
  toString,
  type XYZTuple,
} from '@4bitlabs/color-space/xyz';

const cornflowerBlue: XYZTuple = create(50.39, 57.009, 86.941);
const black: XYZTuple = create(0, 0, 0);

// Mix cornflowerBlue and black at 50% in XYZ color-space.
const mixed = mix(cornflowerBlue, black, 0.5);

console.log(toString(mixed)); // color(xyz 0.251 0.285 0.434)

CIE-LAB colors

import {
  create,
  mix,
  toString,
  type LabTuple,
} from '@4bitlabs/color-space/lab';

const forestGreen: LabTuple = create(50.593, -49.586, 45.015);
const white: LabTuple = create(100, -0, -0.009);

// Mix forestGreen and white at 50% in CIE-Lab color-space.
const mixed = mix(forestGreen, white, 0.5);

console.log(toString(mixed)); // lab(75.297 -24.793 22.503)

Oklab colors

import { create, mix, type okLabTuple } from '@4bitlabs/color-space/oklab';

const salmon: okLabTuple = create(0.8, 0.144, 0.083);
const cyan: okLabTuple = create(0.8, -0.125, -0.217);

// Mix salmon and cyan at 50% in okLab color-space.
const mixed = mix(salmon, cyan, 0.5);

console.log(mixed); // oklab(0.8 0.009 -0.067)

Conversions

sRGB ➡️ XYZ

import { sRGB } from '@4bitlabs/color-space';
const xyz = sRGB.toXYZ(color);

XYZ ➡️ Lab:

import { XYZ } from '@4bitlabs/color-space';
const lab = XYZ.toLab(color);

XYZ ➡️ okLab:

import { XYZ } from '@4bitlabs/color-space';
const oklab = XYZ.toOkLab(color);

okLab ➡️ XYZ:

import { okLab } from '@4bitlabs/color-space';
const xyz = okLab.toXYZ(color);

Lab ➡️ XYZ:

import { Lab } from '@4bitlabs/color-space';
const xyz = Lab.toXYZ(color);

XYZ ➡️ sRGB:

import { XYZ } from '@4bitlabs/color-space';
const xyz = XYZ.toSRGB(color);

sRGB ➡️ linear-RGB:

import { sRGB } from '@4bitlabs/color-space';
const linearRGB = sRGB.toLinearRGB(color);

linear-RGB ➡️ sRGB:

import { linearRGB } from '@4bitlabs/color-space';
const sRBG = linearRGB.toSRGB(color);

Serialization & Storage

The color objects are backed by a simple-array that are easy and safe to serialize and deserialize, however you like. They also do not require any special parsing phase after deserialization, you can just use them like you normally would use them.

import { fromHex, toString } from '@4bitlabs/srgb';

const themeColor = fromHex('#ff6347');

const payload = { theme: { primaryColor: themeColor } };
const json = JSON.stringify(payload);

/* { "theme": { "primaryColor": ["sRGB", 255, 99, 71] } } */

const {
  theme: { primaryColor },
} = JSON.parse(json);

console.log(toString(primaryColor)); // rgb(255 99 71);

If you are parsing from a untrusted or unverifed source, then you can use the included type-predicates to enforce proper structure:

import { toString, isSRGBTuple } from '@4bitlabs/srgb';

const {
  theme: { primaryColor },
} = JSON.parse(json);

if (isSRGBTuple(primaryColor)) {
  // primaryColor is definitely a sRGB color
  console.log(toString(primaryColor)); // rgb(255 99 71);
}