Helpers.java

    /**
     * Calculates if the given textColor is readable when laid ontop of the given backgroundColor.
     *
     * http://www.seas.upenn.edu/~cse400/CSE400_2012_2013/reports/01_report.pdf
     */
    public static boolean isTextReadable(int backgroundColor, int textColor) {
        double brightnessBackground = (299*Color.red(backgroundColor) + 587*Color.green(backgroundColor) + 114*Color.blue(backgroundColor)) / 1000.0;
        double brightnessText = (299*Color.red(textColor) + 587*Color.green(textColor) + 114*Color.blue(textColor)) / 1000.0;

        double brightnessDelta = Math.abs(brightnessBackground - brightnessText);
        double hueDelta = Math.abs(Color.red(backgroundColor) - Color.red(textColor)) +
                Math.abs(Color.green(backgroundColor) - Color.green(textColor)) + Math.abs(Color.blue(backgroundColor) - Color.blue(textColor));

        return brightnessDelta > 125 && hueDelta > 500;
    }