avgRGB.js

function avgRGB() {
    var args = arguments;
    var total = [0,0,0];
    
    for (i=0; i<args.length; i++) {
        total[0] += args[i][0];
        total[1] += args[i][1];
        total[2] += args[i][2];
    }
    
    for (i=0; i<total.length; i++) {
        total[i] = Math.round(total[i] / args.length);
    }
    
    return total
}

// avgRGB([255,0,10],[0,0,255]) -> [128, 0, 133]