This is my upload.php im unsure what variable im looking for

PHP Code: 
<?php


    
require_once('./inc/config.php');

    if(
$settings['SET_DIS_UPLOAD'] && !checklogin()){
        
header('Location: index.php');
        exit();
    }

// set time out timer to 10mins
    
ini_set("max_execution_time""600");
    
ini_set("max_input_time""600");

//unset session
    
unset($_SESSION['upload']);
    unset(
$_SESSION['err']);

////////////////////////////////////////////////////////////////////////////////////
// UPLOAD CODE START

// see if user is banned
    
if (db_isBanned()){
        
sendError($LANGUAGE_PACK["site_upload_banned"]);
    }

// see if a image url has been posted
    
if((isset($_POST['imgUrl']) && !empty($_POST['imgUrl'])) || isset($imgApiUrl)){
        
$image['URL'] = input(isset($_POST['imgUrl'])?$_POST['imgUrl']:$imgApiUrl);
        require_once(
"lib/remoteImage.class.php");
        
$remoteImage = new remoteImages($DIR_TEMP,$settings,$LANGUAGE_PACK);
        
$remoteImage->validExtensions    $imgFormats;
        
$remoteImage->validType            $acceptedFormats;
        
$remoteImage->minDimensions        $IMG_MIN_SIZE;
        
$remoteImage->maxDimensions        $IMG_MAX_SIZE;

        if(
$remoteImage->getImage($image['URL'])){
        
//check that a file has been found and copyed to the temp dir
            
if(!is_null($remoteImage->file)){
                
$_FILES $remoteImage->file;
            }
        }else{
            
sendError($remoteImage->error);
        }
    }

    if(    (
$_SERVER['REQUEST_METHOD'] == 'POST' ||
        isset(
$api)) &&
        
$_FILES['file']['name'][0] !='' && 
        !isset(
$_SESSION['err'])){

        require_once(
"./lib/resize.class.php");
        require_once(
"./lib/phpDupeImage.php");

        
$imgCount 0;

        for(
$i=0$i count($_FILES['file']['name']);++$i){
        
        
// setup image var
            
$pieces        explode("?"$_FILES['file']['name'][$i]);
            
$pathInfo    pathinfo($_FILES['file']['name'][$i]);
            
$imgSize     = @getimagesize($_FILES['file']['tmp_name'][$i]);

            
$image['name']    = $pieces[0];
            
$image['alt']    = removeSymbols(input(!empty($_POST["alt"][$i])?$_POST["alt"][$i]:$pathInfo['filename']));
            
$image['temp']    = $_FILES['file']['tmp_name'][$i];
            
$image['type']    = $imgSize['mime'];
            
$image['size']    = ($_FILES['file']['size'][$i] < 1?@filesize($file_tmp_name):$_FILES['file']['size'][$i]);
            
$removeList[]    = $image['temp'];

        
//check it's a image & set image extension
            
if(!$image['ext'] = get_extension$image['type'], false )){
                
sendError(sprintf($LANGUAGE_PACK["site_upload_types_accepted"],implode(", ",$imgFormats)),'extension');
                continue;
            }

        
//min size(pixels)
            
if ($imgSize[0] < $IMG_MIN_SIZE || $imgSize[1] < $IMG_MIN_SIZE ){
                
sendError(sprintf($LANGUAGE_PACK["site_upload_to_small"],$IMG_MIN_SIZE.'x'.$IMG_MIN_SIZE),'tosmall');
                continue;
            }

        
// max size(pixels)
            
if ($imgSize[0] > $IMG_MAX_SIZE || $imgSize[1] > $IMG_MAX_SIZE ){
                
sendError(sprintf($LANGUAGE_PACK["site_upload_to_big"],$IMG_MAX_SIZE.'x'.$IMG_MAX_SIZE));
                continue;
            }

        
//Check file size (kb)
            
if($image['size'] > $settings['SET_MAXSIZE']){
                
sendError(sprintf($LANGUAGE_PACK["site_upload_size_accepted"],format_size($settings['SET_MAXSIZE'])),'tobig');
                continue;
            }

        
//Make Image fingerprint
            
$finger = new phpDupeImage();
            
$fingerprint $finger->fingerprint($image['temp']);

        
//check for Duplicate Images
            
if($settings['SET_NODUPLICATE']){
            
// If similar files exist, check them
                
if($fp=findImage('fingerprint',$fingerprint)){
                    foreach(
$fp as $fpItem){
                        if (
$finger->are_duplicates($image['temp'],imageAddress(1,$fpItem))){
                            
$dupFound true;
                            break;
                        }
                    }
                    if(isset(
$dupFound)){
                        
sendError($LANGUAGE_PACK["upload_duplicate_found"],'duplicate');
                        continue;
                    }
                }
            }

        
//New random name
        //Number of Possible Combinations
        //  3 digit code 46656
        //  4 digit code 1679616
        //  5 digit code 60466176
            
$image['id'] = createHash(4,true);

        
//random delete ID
            
$image['did'] = $image['id'].createHash(6);

        
//Image address
            
$image['new']        = $image['id'].'.'.$image['ext'];
            
$image['address']    = $DIR_IMAGE.$image['new'];

        
// convert BMP to JPG and PSD to PNG
            
if(in_array($image['ext'],array('psd','bmp'))){
            
//Reset Image address
                
$image['ext']        = ($image['ext'] == 'psd'?$PNG_SAVE_EXT:$JPG_SAVE_EXT);
                
$image['new']        = $image['id'].'.'.$image['ext'];
                
$image['address']    = $DIR_IMAGE.$image['new'];
            
// convert psd/bmp to png
                
$convert = new resize($image['temp']);
                
$convert->imageConvert($image['address'],($image['ext'] == 'psd'?$PNG_QUALITY:$JPG_QUALITY));
                
$convert->destroyImage();
            }
        
        
//move image from remote server
            
elseif(isset($image['URL']) && input($image['URL']) != ''){
                @
copy($image['temp'],$image['address']);
            }
        
        
//move uploaded image
            
else{
                
move_uploaded_file($image['temp'],$image['address']);
            }

        
// move file check
            
if(!file_exists($image['address'])){
                
sendError($LANGUAGE_PACK["site_upload_err"].' .','filemove');
                continue;
            }

        
//Resize image if needed
            
if ($settings['SET_RESIZE_IMG_ON']) {

                if((isset(
$_POST['new_width'][$i]) && !empty($_POST['new_width'][$i])) ||
                    (isset(
$_POST['new_height'][$i]) && !empty($_POST['new_height'][$i]))){

                    
$new_dim = new resize($image['address']);
                    
$new_dim -> stretchSmallImages(TRUE);

                    if(!empty(
$_POST['new_width'][$i]) && !empty($_POST['new_height'][$i])){
                        
$new_dim -> resizeImage($_POST['new_width'][$i], $_POST['new_height'][$i], 'exact');
                    }
                    elseif(!empty(
$_POST['new_width'][$i]) && empty($_POST['new_height'][$i])){
                        
$new_dim -> resizeImage($_POST['new_width'][$i], $imgSize[0], 'landscape');
                    }
                    elseif(empty(
$_POST['new_width'][$i]) && !empty($_POST['new_height'][$i])){
                        
$new_dim -> resizeImage($imgSize[1], $_POST['new_height'][$i], 'portrait');
                    }

                    
$new_dim -> saveImage($image['address'],100);
                    
$new_dim -> destroyImage();
                    
$imgSize = @getimagesize($image['address']);// update image size for db
                
}
            }


        
//Thumb address
            
$THUMB_ADDRESS $DIR_THUMB.$image['new'];
            
$THUMB_MID_ADDRESS $DIR_THUMB_MID.$image['new'];

        
// thumb
            
$resize = new resize($image['address']);
            
$resize ->setMemoryLimit ($IMG_MEMORY_LIMIT);
            
$resize ->setTweakFactor ($IMG_TWEAK_FACTOR);
        
// make thumb
            
$resize -> resizeImage($THUMB_MID_MAX_WIDTH$THUMB_MID_MAX_HEIGHT$THUMB_MID_OPTION);
            
$resize -> saveImage($THUMB_MID_ADDRESS, ($image['ext'] == 'png'?$PNG_QUALITY:$JPG_QUALITY));
        
// make small thumb
            
$resize -> resizeImage($THUMB_MAX_WIDTH$THUMB_MAX_HEIGHT$THUMB_OPTION);
            
$resize -> saveImage($THUMB_ADDRESS, ($image['ext'] == 'png'?$PNG_QUALITY:$JPG_QUALITY));
            
$resize -> destroyImage();

        
//see if thumb's got made
            
if(!file_exists($THUMB_ADDRESS) || !file_exists($THUMB_MID_ADDRESS)){
                @
unlink($image['address']);
                @
unlink($THUMB_ADDRESS);
                @
unlink($THUMB_MID_ADDRESS);
                
sendError($LANGUAGE_PACK["site_upload_err"].' ..','thumbmade');
                continue;
            }

        
// see if we need to get a short url for the image
            
if (isset($_POST['shorturl'][$i]) && $_POST['shorturl'][$i] == && $settings['SET_SHORT_URL_ON']){
                
$shorturl shorturl_url('http://'.$_SERVER['HTTP_HOST'].preg_replace('/\/([^\/]+?)$/''/'$_SERVER['PHP_SELF']).'?di='.$image['id']);
            }

        
// get thumb's file size
            
$image['size'] = @filesize($image['address']);
            
$thumbsize = @filesize($THUMB_MID_ADDRESS);
            
$sthumbsize = @filesize($THUMB_ADDRESS);

        
// Make image info array to save to db
            
$newImageArray = array(    'id'        => $image['id'],
                                    
'name'        => $image['name'],
                                    
'alt'        => $image['alt'],
                                    
'added'        => time(),
                                    
'ext'        => $image['ext'],
                                    
'ip'        => $_SERVER['REMOTE_ADDR'],
                                    
'size'        => $image['size'],
                                    
'deleteid'    => $image['did'],
                                    
'thumbsize' => $thumbsize,
                                    
'sthumbsize'=> $sthumbsize,
                                    
'private'    => (isset($_POST['private'][$i])?1:0),
                                    
'report'    => 0,
                                    
'shorturl'    => (!isset($shorturl)?null:$shorturl),
                                    
'fingerprint'  =>$fingerprint,
                                    );

        
//save new image to database
            
if(addNewImage($newImageArray)){

            
// save image to upload array to be sent to thumb page
                
$_SESSION['upload'][] = array('id' => $image['id'],'did' => $image['did']);

            
// count images uploaded
                
$imgCount++;
                if(
$imgCount >= $settings['SET_MAX_UPLOAD'] && !checklogin()){
                    break; 
// break upload loop as you have updated max number of images in one go...
                
}

            }else{
                
sendError($LANGUAGE_PACK["site_index_delete_image_err_db"],'savedb');
                continue;
            }
        }
// end image upload loop
    
}
// error uploading image
    
elseif(!isset($_SESSION['err'])){
        
sendError($LANGUAGE_PACK["site_upload_err"].' ...','uk');
    }

// remove temp images
    
if(isset($removeList)){
        foreach (
$removeList as $tempImg){
            
// remove old file
                
if(file_exists($tempImg)){
                    
unlink($tempImg);
                }
        }
    }

// UPLOAD CODE END
////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////
// MAKE PAGE

// error send back to home page and show the error
    
if(!isset($_SESSION['upload'])){
        
header('Location: '$settings['SET_SITEURL'].'/index.php');
        exit();
    }

// open thumb page and show upload images
    
header('Location: '$settings['SET_SITEURL'].'/thumbnail.php');
    die();


// MAKE PAGE END
////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////
// functions

// send error back to index page
    
function sendError($msg,$id=''){
        
$_SESSION['err'][$id] = $msg;
    }

// get file ext from mine
    
function get_extension($imagetype$includeDot false){
        global 
$acceptedFormats;
        if(empty(
$imagetype)) return false;
        
$dot $includeDot '.' '';
        if(isset(
$acceptedFormats[$imagetype])){
            return 
$dot.$acceptedFormats[$imagetype];
        }
        return 
false;
    }


// very simple hash function to generate a random string
    
function createHash($length=5,$check=null){
        
$valid    0;
        
$hash    '';
        while(!
$valid){
            for(
$i=0;$i<$length;++$i){
            
// if you want to add letters you will have to change the id to varchar instead of int
                
$possibleValues "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
            
// pick a random character from the possible ones
                
$hash .= substr($possibleValuesmt_rand(0strlen($possibleValues)-1), 1);
            }
        
// checks if the hash allready exists in the db
            
if(is_null($check) || !getImage($hash)){
                
$valid 1;
            }
        }
        return 
$hash;
    }