cie.js

  !npm type definitions  
 
   
Node.js wrapper around CIE.sh.

📕 TOC

- 📃 About
- 📦 Dependencies
- 🛠 Usage
- 🖥 CLI
- 🐳 CLI by Docker
- 📄 Javascript
- 🔗 API
- 1976 Formula
- 1994 Formula
- 2000 Formula
- 🎉 Acknowledgements
- 🥝 Lisence

📃 About

This package calculates the color difference between two colors using the color difference formula in LAB Delta E established by the Commission internationale de l'éclairage (CIE).
It also uses Bash Script for the main logic, so the following is required to run it.

$3

- bash >= 5.0
- grep
- awk
- sed
- cat
- bc

🛠 Usage

$3

``console
$ yarn global add cie.js # npm install -g cie.js

$ cie-js -h
Usage: cie-js [options] [command]

Derives the color difference using the method defined by LAB Delta E (CIE76, CIE94, CIEDE2000).

Options:
-v, --version Output the version number
-h, --help display help for command

Commands:
dE76 Use the CIE 1976 color difference formula.
dE94 Use the CIE 1994 color difference formula.
dE00 Use the CIEDE2000 color difference formula.
help [command] display help for command

TL;DR
$ cie-js dE76 50.0000 2.6772 \ -79.7751 50.0000 0.0000 \ -82.7485
$ cie-js dE94 -g 50.0000 2.6772 \ -79.7751 50.0000 0.0000 \ -82.7485
$ cie-js dE00 50.0000 2.6772 \ -79.7751 50.0000 0.0000 \ -82.7485
$ echo 50.0000,2.6772,-79.7751,50.0000,0.0000,-82.7485 | cie-js dE94 -t

$ cie-js dE76 50.0000 2.6772 \ -79.7751 50.0000 0.0000 \ -82.7485
4.0011
$ cie-js dE94 -g 50.0000 2.6772 \ -79.7751 50.0000 0.0000 \ -82.7485
1.3950
`
`bash


Read from file

$ cat example.txt
50.0000 2.6772 -79.7751 50.0000 0.0000 -82.7485
50.0000 3.1571 -77.2803 50.0000 0.0000 -82.7485
50.0000 2.8361 -74.0200 50.0000 0.0000 -82.7485
50.0000 -1.3802 -84.2814 50.0000 0.0000 -82.7485
50.0000 -1.1848 -84.8006 50.0000 0.0000 -82.7485
50.0000 -0.9009 -85.5211 50.0000 0.0000 -82.7485

$ cat example.txt | cie-js dE76
4.0011
6.3142
9.1777
2.0627
2.3696
2.9153
`

$3


`bash

Install

$ docker pull ghcr.io/redpeacock78/cie.js

Write the following function in .bashrc etc.

cie-js() {
[[ -t 0 ]] && T="t" || T=""
docker run -i"${T}" --rm ghcr.io/redpeacock78/cie.js:latest "${@}"
}

Run!

$ source ~/.bashrc
$ cie-js dE76 50.0000 2.6772 \ -79.7751 50.0000 0.0000 \ -82.7485
4.0011

Update

$ docker pull ghcr.io/redpeacock78/cie.js && docker rmi -f $(docker images | grep ghcr.io/redpeacock78/cie.js | grep none | awk '{print $3}')

Uninstall

$ docker rmi -f $(docker images | grep ghcr.io/redpeacock78/cie.js | grep latest | awk '{print $3}')
`

$3

`javascript
import * as lab from 'cie.js'; // const lab = require('cie.js');

const color_1 = { L: 50.0000, a: 50.0000, b: 0.0000 };
const color_2 = { L: 40.0000, a: 50.0000, b: 0.0000 };
(async () => {
await lab.dE76(color_1, color_2).then((result) => {
console.log(result);
})
})();
// => 10.0000
`




🔗 API

$3


The CIE 1976 color difference formula is the first color difference formula defined, and is calculated as the Euclidean distance in CIELAB coordinates.
- lab.dE76(color_1: {[key: string]: number}, color_2: {[key: string]: number}): Promise
`javascript
const color_1 = { L: 50.0000, a: 2.6772, b: -79.7751 };
const color_2 = { L: 50.0000, a: 0.0000, b: -82.7485 };
(async () => {
console.log(await lab.dE76(color_1, color_2));
})();
// => 4.0011
`

$3

ΔE(1994) is calculated from the difference in brightness, saturation, and hue in the L\C\h\ color space, which is calculated from the L\a\b\ color space. It also introduces a weighting factor for specific applications, derived from the allowable values for automotive paints.
- lab.dE94.textile(color_1: {[key: string]: number}, color_2: {[key: string]: number}): Promise
![](https://render.githubusercontent.com/render/math?math=Weighting\%20Factor\%20(k_L=1,%20K_1=0.045,%20K_2=0.015))
`javascript
const color_1 = { L: 50.0000, a: 2.6772, b: -79.7751 };
const color_2 = { L: 50.0000, a: 0.0000, b: -82.7485 };
(async () => {
console.log(await lab.dE94.textile(color_1, color_2));
})();
// => 1.4230
`
- lab.dE94.graphicArts(color_1: {[key: string]: number}, color_2: {[key: string]: number}): Promise
![](https://render.githubusercontent.com/render/math?math=Weighting\%20Factor\%20(k_L=2,%20K_1=0.048,%20K_2=0.014))
`javascript
const color_1 = { L: 50.0000, a: 2.6772, b: -79.7751 };
const color_2 = { L: 50.0000, a: 0.0000, b: -82.7485 };
(async () => {
console.log(await lab.dE94.graphicArts(color_1, color_2));
})();
// => 1.3950
`

$3

Since the CIE 1994 definition did not sufficiently ensure perceived uniformity, the CIE revised the definition and established the standard.
- lab.dE00(color_1: {[key: string]: number}, color_2: {[key: string]: number}): Promise
`javascript
const color_1 = { L: 50.0000, a: 2.6772, b: -79.7751 };
const color_2 = { L: 50.0000, a: 0.0000, b: -82.7485 };
(async () => {
console.log(await lab.dE00(color_1, color_2));
})();
// => 2.0425
``

🎉 Acknowledgements

- JavaScriptでCIE94色差計算 - Qiita
- JavaScriptでCIEDE2000色差計算 - Qiita
- 色の距離(色差)の計算方法 ‒ Qiita
- 色差 - Wikipedia
- Color Difference Calculator
- Gaurav Sharma
- 色差計算器 (CIE76, CIE2000) ‒ でじたる小屋

🥝 Lisence

MIT