preLoad();

function preLoad() {
    if (document.images) {
        pic1 = loadImage(94, 94, "/images/btn-inhoud_on.jpg");
        pic2 = loadImage(94, 94, "/images/btn-locatie_on.jpg");
        pic3 = loadImage(94, 94, "/images/btn-cast_on.jpg");
        pic4 = loadImage(94, 94, "/images/btn-speeldata_on.jpg");
        pic5 = loadImage(94, 94, "/images/btn-pers_on.jpg");
    }
}

function loadImage(width, height, url) {
    pic = new Image(width, height);
    pic.src = url;

    return pic
}

function over(src) {
    if (src.indexOf("_on.jpg") > -1) {
        return src;
    } else {
        return src.replace(".jpg", "_on.jpg");
    }
}

function out(src) {
    return src.replace("_on.jpg", ".jpg");
}