colorvert

This node module converts colors between CMYK, Lab, XYZ, RGB, HSL, HSV, and Hex colorspaces. Colorvert uses the transicc node module to provide ICC profile-based color conversions between several color spaces. If you only need conversions between ICC profiles (CMYK, Lab, XYZ, and RGB), look to that module.

For a JSON HTTP API: Check out the colorvert-api node module. It uses this module and express to serve HTTP endpoints that convert the input color to all other colorspaces. It's ideal for batch color conversions.

Installation Requirements

You must first install LittleCMS, an open source library written mostly in C for converting colors using ICC profiles. This shell script will get you there.

git clone https://github.com/mm2/Little-CMS.git
cd Little-CMS
./configure 
make 
make check 
sudo make install

Once you've installed that dependency, you're ready to install colorvert and get goin'!

npm install colorvert --save

Quick Examples

var cvert = require( "colorvert" );

// CMYK, XYZ, and Lab-based conversions require
// you to provide a callback function.
cvert.cmyk_to_rgb( 100, 0, 0, 0, function( err, rgb ){
	console.log( rgb );
});

// RGB, HSL, HSV, and hex conversions simply 
// return values.
var hex = cvert.rgb_to_hex( 0, 172, 236 );

Single Conversion

If you only need to convert from one color to another, just include that specific conversion module - it'll keep node from caching extra modules it won't need. Here's an example:

var cmyk_to_hex = require( "colorvert/cmyk/hex" );

cmyk_to_hex( 100, 0, 0, 0, function( err, hex ){
	console.log( hex );
});

CMYK, Lab & XYZ Conversions

These conversions require us to use the transicc node module that interacts with a command line utility. As a result, we have to wait for the response before doing anything with it, so you must provide a callback when converting to or from any of these formats. Here's an example:

cvert.cmyk_to_rgb( 100, 0, 0, 0, function( err, rgb ){
	console.log( rgb );
});

Math-only Conversions

If you're converting between RGB, HSL, HSV, or hex, the functions will simply return the value for you to use right away. Here's how that'll look.

var hex = cvert.rgb_to_hex( 0, 146, 210 );
console.log( hex );

Convert to ALL Other Colorspaces

Each of the colorspaces includes a module that converts to all other colorspaces. As a bonus, the output will also include the hex code of the inverted color, and will suggest the most readable text color to display over the input color. Use it like so:

cvert.cmyk_to_all( 100, 0, 0, 0, function( err, all ){
	console.log( all );
	/*
	Outputs:
	{
		"cmyk": {
			"c": "100",
			"m": "0",
			"y": "0",
			"k": "0"
		},
		"lab": {
			"l": 59,
			"a": -37,
			"b": -49
		},
		"hex": "#00a0e0",
		"hex_inverted": "#ff5f1f",
		"hex_readable": "#ffffff",
		"hsl": {
			"h": 197,
			"s": 100,
			"l": 43
		},
		"hsv": {
			"h": 197,
			"s": 100,
			"v": 87
		},
		"rgb": {
			"r": 0,
			"g": 160,
			"b": 224
		},
		"xyz": {
			"x": 52,
			"y": 71,
			"z": 197
		}
	}
	*/
});

Warning! :)

This module has been pretty reliable during all my tests and with everything I've thrown at it. That said, I haven't written tests for everything yet, so be sure to test it in your environment and with your input - if you find any issues, please post them on Github or submit a pull request!