Hi,
I've tried to use Captcha on my server (RedHat Enterprise 4) using what came with it (PHP, MYSQL, APACHE) but it didn't display the image (gave me box with cross inside) So I downloaded XAMPP the latest version 1.6 and installed on this server, but still get the same result.
Here is the code that I'm using:
<?php
error_reporting(E_ALL);
session_start();
/*
* File: CaptchaSecurityImages.php
* Author: Simon Jarvis
* Copyright: 2006 Simon Jarvis
* Date: 03/08/06
* Updated: 07/02/07
* Requirements: PHP 4/5 with GD and FreeType libraries
* Link: http://www.white-hat-web-design.co.uk/articles/php-captcha.php
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details:
* http://www.gnu.org/licenses/gpl.html
*
*/
class CaptchaSecurityImages {
var $font = 'monofont.ttf';
function generateCode($characters) {
/* list all possible characters, similar looking characters and vowels have been removed */
$possible = '23456789bcdfghjkmnpqrstvwxyz';
$code = '';
$i = 0;
while ($i < $characters) {
$code .= substr($possible, mt_rand(0, strlen($possible)-1), 1);
$i++;
}
return $code;
}
function CaptchaSecurityImages($width='120',$height='40',$characters='6') {
$code = $this->generateCode($characters);
/* font size will be 75% of the image height */
$font_size = $height * 0.75;
$image = @imagecreate($width, $height) or die('Cannot initialize new GD image stream');
/* set the colours */
$background_color = imagecolorallocate($image, 255, 255, 255);
$text_color = imagecolorallocate($image, 20, 40, 100);
$noise_color = imagecolorallocate($image, 100, 120, 180);
/* generate random dots in background */
for( $i=0; $i<($width*$height)/3; $i++ ) {
imagefilledellipse($image, mt_rand(0,$width), mt_rand(0,$height), 1, 1, $noise_color);
}
/* generate random lines in background */
for( $i=0; $i<($width*$height)/150; $i++ ) {
imageline($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 , $code) or die('Error in imagettftext function');
/* output captcha image to browser */
header('Content-Type: image/jpeg');
imagejpeg($image);
imagedestroy($image);
$_SESSION['security_code'] = $code;
}
}
$width = isset($_GET['width']) ? $_GET['width'] : '120';
$height = isset($_GET['height']) ? $_GET['height'] : '40';
$characters = isset($_GET['characters']) && $_GET['characters'] > 1 ? $_GET['characters'] : '6';
$captcha = new CaptchaSecurityImages($width,$height,$characters);
?>
And here is the code that using it:
<?php
session_start();
if( isset($_POST['submit'])) {
if( $_SESSION['security_code'] == $_POST['security_code'] && !empty($_SESSION['security_code'] ) ) {
// Insert you code for processing the form here, e.g emailing the submission, entering it into a database.
echo 'Thank you. Your message said "'.$_POST['message'].'"';
} else {
// Insert your code for showing an error message here
echo 'Sorry, you have provided an invalid security code';
}
} else {
?>
<form action="form.php" method="post">
<label for="name">Name: </label><input type="text" name="name" id="name" /><br />
<label for="email">Email: </label><input type="text" name="email" id="email" /><br />
<label for="message">Message: </label><textarea rows="5" cols="30" name="message" id="message"></textarea><br />
<img src="CaptchaSecurityImages.php?width=100&height=40&characters=5" /><br />
<label for="security_code">Security Code: </label><input id="security_code" name="security_code" type="text" /><br />
<input type="submit" name="submit" value="Submit" />
</form>
<?php
}
?>
I've uploaded it on a remote server and it worked fine. When I ran phpinfo(); on the remote GD was there but not on the local server, I thought XAMP will solve it but it didn't and I don't know how to make it working on Linux, on windows its just remove ; from:
;extension=php_gd2.dll
Can you please help me?
Thank you