Ideal Text Color

ideal_text_color.js

/*
* Finds the ideal text color for legibility on the background color provided
* Example i/o: idealTextColor('#000000') -> #ffffff
*/
function idealTextColor(background) {

        var r = background.substring(1, 3);
        var g = background.substring(3, 5);
        var b = background.substring(5, 7);        

        var components = {R: parseInt(r, 16),G: parseInt(g, 16),B: parseInt(b, 16)};
        var nThreshold = 105;

       var bgDelta = (components.R * 0.299) + (components.G * 0.587) + (components.B * 0.114);
       return ((255 - bgDelta) < nThreshold) ? "#000000" : "#ffffff";
}