img_width = 10; 
img_height = 10;
timer = null;
 
function imageGrow() {
    growImg = document.getElementById('imageResize').style
 
    growImg.width= img_width;
    growImg.height= img_height;
 
    if(img_width != 500) {
        img_width += 10;
        img_height += 5;
        timer = setTimeout('imageGrow()', 3);
    } else {
        clearTimeout('timer');
    }
}