function openurl(url) {
    var topvar;
    var leftvar;
    topvar = (screen.height / 2) - (651 / 2);
    leftvar = (screen.width / 2) - (560 / 2);
    select_image_box = window.open(url,'openurl','width=560,height=651,top='+topvar+',left='+leftvar+',scrollbars,status,resizable');
    select_image_box.focus();
}