Location: PHPKode > scripts > Image-Based CAPTCHA for PHP > README.TXT
PHP Library and Sample Code for Confident CAPTCHA
version 20100621_PHP

Thank you for downloading this library and sample code.  The included files
 * README.TXT - This document
 * captchalib.php - The PHP library
 * config.php - Configuration template
 * callback.php - The 
 * sample.php - The PHP sample


 * This library requires PHP version 5.0 or later.
 * PHP must have cURL and SimpleXML support built in and enabled.
 * The page that renders the Confident CAPTCHA requires jQuery 1.4.2.


 1. Sign up for Confident CAPTCHA at:


 2. Create an account at:


 3. Modify config.php, filling in the API credentials from:


 4. Still in config.php, set the value of $callback_url to the relative URL to
 5. Integrate the library into your code.  You need captchalib.php, callback.php,
 and a (customized) config.php in your project.  Look at sample.php for 
 integration ideas.  Be sure to include jQuery in your page.

Please send your questions and feedback to:



20100610_PHP - June 10th, 2010
 * Original (versioned) release

20100621_PHP - June 21st, 2010
 * Updated to work with API version 20100610
 * Support the new namespaced HTML and JavaScript elements
 * CAPTCHA parameters are stored in session, so that similar CAPTCHA can be created on callback
 * Sample implements "fail open" strategy - Forms work even when there is configuration or server issues.
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