var preloadImgs = new Array();
var imageArray = new Array();

function preloadImages() {
    for (var i = 0; i < preloadImgs.length; i++) {
        var img = new Image();
        img.src = preloadImgs[i];
        imageArray.push(img);
    }
}

function highlite(img) {
    img.src = img.src.replace(/_low/, "_high");
}

function restore(img) {
    img.src = img.src.replace(/_high/, "_low");
}