Uploadeaza si redimensioneaza o poza

<?php 

if(isset($_POST['Submit'])) 

{ 
     $size = 150; // dimensiunea thumbnail-ului

     $filedir = 'pics/'; // directorul imaginii pe care o vei uploada
     $thumbdir = 'pics/'; // directorul imaginii thumbnail
     $prefix = 'small_'; // prefixul adaugat imaginii

     $maxfile = '2000000'; 
     $mode = '0666'; 
      
     $userfile_name = $_FILES['image']['name']; 
     $userfile_tmp = $_FILES['image']['tmp_name']; 
     $userfile_size = $_FILES['image']['size']; 
     $userfile_type = $_FILES['image']['type']; 
      
     if (isset($_FILES['image']['name'])) 
     { 
         $prod_img = $filedir.$userfile_name; 

         $prod_img_thumb = $thumbdir.$prefix.$userfile_name; 
         move_uploaded_file($userfile_tmp, $prod_img); 
         chmod ($prod_img, octdec($mode)); 
          
         $sizes = getimagesize($prod_img); 

         $aspect_ratio = $sizes[1]/$sizes[0]; 

         if ($sizes[1] <= $size) 
         { 
             $new_width = $sizes[0]; 
             $new_height = $sizes[1]; 
         }else{ 
             $new_height = $size; 
             $new_width = abs($new_height/$aspect_ratio); 
         } 

         $destimg=ImageCreateTrueColor($new_width,$new_height) or die('Problem In Creating image'); 
         $srcimg=ImageCreateFromJPEG($prod_img) or die('Problem In opening Source Image'); 
         ImageCopyResized($destimg,$srcimg,0,0,0,0,$new_width,$new_height,ImageSX($srcimg),ImageSY($srcimg)) or die('Problem In resizing'); 
         ImageJPEG($destimg,$prod_img_thumb,90) or die('Problem In saving'); 
         imagedestroy($destimg); 
     } 

     echo ' 
     <a href="'.$prod_img.'"> 
         <img src="'.$prod_img_thumb.'" width="'.$new_width.'" heigt="'.$new_height.'"> 
     </a>'; 

}else{ 

     echo ' 
     <form method="POST" action="'.$_SERVER['PHP_SELF'].'" enctype="multipart/form-data"> 
     <input type="file" name="image"><p> 
     <input type="Submit" name="Submit" value="Submit"> 
     </form>'; 
} 

?>