system: Linux mars.sprixweb.com 3.10.0-1160.119.1.el7.x86_64 #1 SMP Tue Jun 4 14:43:51 UTC 2024 x86_64
<?php
session_start();
class Lib_Captcha {
var $font = 'classes/Lib/AlanDen.ttf';
function generateCode($characters) {
/* list all possible characters, similar looking characters and vowels have been removed */
$possible = '1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ';
$code = '';
$i = 0;
while ($i < $characters) {
$code .= substr($possible, mt_rand(0, strlen($possible)-1), 1);
$i++;
}
return $code;
}
function Lib_Captcha($width='120',$height='40',$characters='6') {
$code = $this->generateCode($characters);
/* font size will be 75% of the image height */
$font_size = 40;//$height * 0.45; //10;//
$image = @imagecreate($width, $height) or die('Cannot initialize new GD image stream');
/* set the colours */
$background_color = imagecolorallocate($image, 0, 0, 0);
$text_color = imagecolorallocate($image, 255, 255, 255);
$noise_color = imagecolorallocate($image, 0, 0, 0);
/* generate random dots in background */
for( $i=0; $i<($width*$height)/5; $i++ ) {
imagefilledellipse($image, mt_rand(0,$width), mt_rand(0,$height), 1, 1, $noise_color);
}
/* generate random lines in background */
for( $i=0; $i<($width*$height)/300; $i++ ) {
imageline($image, mt_rand(0,$width), mt_rand(0,$height), mt_rand(0,$width), mt_rand(0,$height), $noise_color);
}
/* create textbox and add text */
$textbox = imagettfbbox($font_size, 0, $this->font, $code) or die('Error in imagettfbbox function');
$x = ($width - $textbox[4])/2;
$y = ($height - $textbox[5])/2;
imagettftext($image, $font_size, 0, $x, $y, $text_color, $this->font , $code) or die('Error in imagettftext function');
/* output captcha image to browser */
header('Content-Type: image/jpeg');
header('Cache-Control: no-cache, must-revalidate');
imagejpeg($image);
imagedestroy($image);
$_SESSION['security_code'] = $code;
}
}
$width = '250';
$height = '90';
$characters = '5';
$captcha = new Lib_Captcha($width,$height,$characters);
?>