ช่วยแก้ไขฟังก์ชันอัพโหลดรูปภาพให้หนูหน่อยค๊ะ

//the new width of the resized image.
$img_thumb_width = 300; // in pixcel
$file_type = $_FILES['img_path']['type'];
       $file_name = $_FILES['img_path']['name'];
       $file_size = $_FILES['img_path']['size'];
       $file_tmp = $_FILES['img_path']['tmp_name'];

       //check if you have selected a file.
       if(!is_uploaded_file($file_tmp)){
          die ('You need to select an image');
          exit(); //exit the script and don't do anything else.
       }
       //check file extension
       $ext = strrchr($file_name,'.');
       $ext = strtolower($ext);
       if (($extlimit == "yes") && (!in_array($ext,$limitedext))) {
          die ('File extension not allowed');
          exit();
       }
       //get the file extension.
       $getExt = explode ('.', $file_name);
       $file_ext = $getExt[count($getExt)-1];

       //create a random file name
       $rand_name = md5(time());
       $rand_name= rand(0,999999999);
       //get the new width variable.
       $ThumbWidth = $img_thumb_width;

       //keep image type
       if($file_size){
          if($file_type == "image/pjpeg" || $file_type == "image/jpeg"){
               $new_img = imagecreatefromjpeg($file_tmp);
           }elseif($file_type == "image/x-png" || $file_type == "image/png"){
               $new_img = imagecreatefrompng($file_tmp);
           }elseif($file_type == "image/gif"){
               $new_img = imagecreatefromgif($file_tmp);
           }
           //list width and height and keep height ratio.
           list($width, $height) = getimagesize($file_tmp);
           $imgratio=$width/$height;
           if ($imgratio>1){
              $newwidth = $ThumbWidth;
              $newheight = $ThumbWidth/$imgratio;
           }else{
                 $newheight = $ThumbWidth;
                 $newwidth = $ThumbWidth*$imgratio;
           }
           //function for resize image.
           if (function_exists(imagecreatetruecolor)){
           $resized_img = imagecreatetruecolor($newwidth,$newheight);
           }else{
                 die("Error: Please make sure you have GD library ver 2+");
           }
           imagecopyresized($resized_img, $new_img, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);
           //save image
           ImageJpeg ($resized_img,"$path_thumbs/$rand_name.$file_ext");
           ImageDestroy ($resized_img);
           ImageDestroy ($new_img);
           $img_path = "$path_thumbs/$rand_name.$file_ext";


        }