My Zend Captcha Model:

my code:

<?php

    class Captcha{

     function Captcha(){

        Zend_Loader::loadClass('Zend_Captcha_Image');
        $captcha = new Zend_Captcha_Image();
                $captcha->setTimeout(300)
              ->setWordLen(5)
              ->setHeight(80)
              ->setFont(DIR.'/fonts/FONT.TTF')
             ->setImgDir(DIR.'images/captcha/'); 

               $security_code = $captcha->generate(); 
         require_once 'Zend/Session/Namespace.php';
         Zend_Loader::loadClass('Zend_Session_Namespace');
         $SESSION['captcha_code'] = $security_code;
         $sessionNamespace = new Zend_Session_Namespace('cptc');
 
         $sessionNamespace->code = $security_code;

        return $security_code;
           
     }   
       
    }

?>