View file _modules/captcha/index.php

<?php

    # author Drk in

    session_start();

    $width = 73;

    $height = 38;

    $im = imagecreatetruecolor($width, $height);

    imagefill($im, 0, 0, imagecolorallocate($im, 255, 255, 255));
       
    $captcha = NULL;

    for($i=0; $i<5; $i++):

    $y = rand(2, 5);

    $x += rand(8, 14);
        
    $captcha .= rand(1, 9);

    imagestring($im, rand(1, 10), $x, $y, $captcha[$i],
    
    imagecolorallocate($im, rand(90, 150), rand(90, 150), rand(90, 150)));

    endfor;    
    
    $_SESSION['captcha'] = $captcha;
       
    header('Content-type: image/jpeg');
    
    imagepng($im);
    
    imagedestroy($im);


?>