View file click/pic.php

<?
session_start();
$_SESSION['pswd']=rand(10000,99999);
list(, , $type,)=@getimagesize("im.jpg");
if ($type==1) {$funci="imagecreatefromgif";} //$funco="imagegif";}
if ($type==2) {$funci="imagecreatefromjpeg";} //$funco="imagejpeg";}
$im1 = @$funci("im.jpg");
$black = ImagecolorAllocate($im1,255,255,255);
ImageString ($im1, 2, 1, -2,"".$_SESSION['pswd']."",$black);
@header("Content-type: image/png");
@imagepng($im1);
?>