Need help to watermark my pictures on upload

what do i edit to add watermark on upload?

<?php
/* $Id: upload.php,v 1.2 2005-11-17 08:02:51-07 brian Exp brian $ */
// vim: expandtab sw=4 ts=4 sts=4:
########################################################################
## Built2Go PHP RateMyPhoto v1.0                                      ##
## ----------------------------------------------------------------   ##
## Copyright © Big Resources, Inc. All Rights Reserved.               ##
## This software must be used in accordance with its licensing        ##
## terms and conditions at: http://www.built2go.com/faq.php           ##
##                                                                    ##
## This file may not be redistributed in whole or significant part.   ##
## ---------------- BUILT2GO IS NOT FREE SOFTWARE -----------------   ##
########################################################################
session_start();
require("config.php");
include_once("$full_path_to_public_program/session.php");

include("templates/main.html.php");
include("templates/leftside.html.php");
include("templates/newimage_header.html");
if(($_SESSION['userid'] AND $_SESSION['pass']) AND ($_COOKIE['id'] AND $_COOKIE['username'])) {
   if($_SESSION['disabled']){
       echo "<td valign=\"top\"><div class=\"error\">$DisabledUser</div>";
       include("templates/newheader_end.html");
       include("templates/footer.html.php");
       exit;
    }
    if (isset($_POST['addpic'])){

        for ($i=0; $i<count($_FILES["Ifile"]["tmp_name"]); $i++){
            if (is_uploaded_file($_FILES["Ifile"]["tmp_name"][$i])){
                $ext = substr(strrchr($_FILES['Ifile']['name'][$i],"."),1);
                $size = @getimagesize($_FILES["Ifile"]["tmp_name"][$i]);
                if(!in_array($_FILES["Ifile"]["type"][$i],$ImageFormat) OR (strstr($_FILES["Ifile"]["name"][$i],"..")!="")){
                    $imageerror= "<div class=\"error\">$NotCorrectFormat</div>\n";
                }elseif ($_FILES["Ifile"]['size'][$i]==0){
                    $imageerror= "<div class=\"error\">$ToSmallUpload</div>\n";
                
                } elseif ($_FILES["Ifile"]["size"][$i]>MAXFILE_SIZE) {
                    $imageerror= "<div class=\"error\">$ToBigUpload[0]</div>\n";
                } else {
                    $fp = fopen($_FILES["Ifile"]["tmp_name"][$i], "rb");
                    $fcontents = fread ($fp, filesize ($_FILES["Ifile"]["tmp_name"][$i]));
                    $sec = date("s");
                    // add 1 to the seconds so the files will have different names.
                    $sec = $sec + $i;
                    $date=date("Y")."-".date("m")."-".date("d")."".date("H")."-".date("i")."-".$sec;
                    $newname= $_SESSION['id']."_".$date.".".$ext;
                    $file1=fopen($upload_dir."/".$newname,"w");
	                fputs($file1,$fcontents);
	                fclose($file1);
                     $local_pic = $newname;

                }

                if (empty($imageerror)){
                    // might have to check for multiple images that are the same.
                    // make sure they can't upload the exact same image and if the image is already there.
                    // see if admin disabled comments, if not get the user choice
                   $comment = ($AdminAllowComments)?valid_id($_POST['comment']):$AdminAllowComments;
                   $U = "INSERT into $pic_tbl (picid,pic_userid,picture,dateadded,ncat,status,comment)
                   VALUES ('','{$_SESSION['id']}','$local_pic','".time()."', '{$_SESSION['gender']}','$SetPending','$comment') ";
                   //echo $U;
                   mysql_query($U) or die(mysql_error());
                   
                   $ImageEmail = str_replace("{USER}", $get_email["userid"],$ImageSubmissionEmail);
                   
                   SendUserEmail($get_email["email"],$ImageSubmissionEmailSubject,$ImageEmail);
                   $success .= str_replace("{IMG_UPLOAD}" ,$local_pic ,$SuccessFile);
                } else {
                    $fail .= str_replace("{IMG_UPLOAD}" ,$_FILES["Ifile"]["name"][$i] ,$FailedFile);
                }

            }

        }
        echo "<div class=\"txt_dgreen_bold02\">$imageerror<br />$fail<br />$success<br />$upload_success</div>";

    } else {

                echo "<div class=\"error\">$NoPicture</div>\n";
                include("templates/newheader_end.html");
                include("templates/upld_form.html.php");
                include("templates/footer.html.php");
                exit;
    }

}

include("templates/newheader_end.html");
include("templates/footer.html.php");
?>

PHP:

 

there are a lot of classes to add watermarks ... look though google