function showImage(url,w,h){
   var imgWin = window.open('', 'url', "height="+h+",width="+w);
   imgWin.document.write(
      '<HTML><TITLE></TITLE><HEAD>'+
      '</HEAD><BODY  leftmargin="0" topmargin="0" marginwidth="0" marginheight="0">'+
      '<IMG src='+url+' width='+w+' height='+h+' onClick="javascript: window.close()">'+
      '</BODY></HTML>'
   );
}