function obal_dvd() {
     window.open("images/obal.jpg","obal_dvd","scrollbars=no,status=no,width=610,height=407,menubar=no,resizable=no,directories=no") ;
   };

function potisk_dvd() {
     window.open("images/potisk.jpg","potisk_dvd","scrollbars=no,status=no,width=621,height=626,menubar=no,resizable=no,directories=no") ;
   };