var WinOpen;

function show_url(src, itswidth, itsheight) {
 	height = parseInt(itsheight);
 	width = parseInt(itswidth);

	p_top=(screen.height-height)/2;
	p_left=(screen.width-width)/2;

    if(WinOpen != null){
     	  WinOpen.close();
          WinOpen  =  window.open(src, "Foto", "closed=yes, toolbar=no, location=no, top="+p_top+", left="+p_left+", directories=no, status=no, menubar=no, scrollbars=yes, resizable=no, width="+width+", height="+height+"");
    }else{
          WinOpen  =  window.open(src, "Foto", "closed=yes, toolbar=no, location=no, top="+p_top+", left="+p_left+", directories=no, status=no, menubar=no, scrollbars=yes, resizable=no, width="+width+", height="+height+"");
}

return WinOpen;

}