eccola!!
JavaScript:
codice:
 function Popup(foto) {    var w = 450;    var h = 250;    var l = Math.floor((screen.width-w)/2);    var t = Math.floor((screen.height-h)/2);    file=foto+"?hidden="+document.inserisci.foto.value;       window.open(file,"","width=" + w + ",height=" + h + ",top=" + t + ",left=" + l);  }
file che aprirà il popup:
codice:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>Inserisci foto</title> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> </head> <body> <div align='center'> <?php if($_GET['hidden']!=''){?> [img]<?php echo"$_GET[hidden]";?>[/img] <?php } ?> <table align="center"> 	<tr><td>     <form enctype="multipart/form-data" method="post" action="" name="uploadform">       Select the foto:        
       <input type="file" name="file1" size="50">       
 	  <input type="hidden" value="<?php echo"$_GET[hidden]";?>" name='fileold' id='fileold'>       <input type="submit" value="invia immagine" name="invio"> 	  <input type="button" value="chiudi" name="chiudi" onclick="self.close()">     </form> 	</td></tr> 	</table> 	</div> </body> </html>