Freecap Captcha
Captcha Version : 1.4.1
Captcha Features : freeCap is a GPL CAPTCHA script to stop spam on guestbooks. It can be used to prevent spam on any form; comment areas, signups, shopping carts - any area of your website where you fear the evil spammers may target. freeCap PHP CAPTCHA boasts a host of features, not only does it offer strong character obfuscation, using random distortion of text and multiple backgrounds, but it also focuses on the security of the implementation. A lot of CAPTCHAs are relatively secure against OCR attacks, but fail to account for other attacks, such as session re-use. freeCap can output in three different image types, uses a custom GD font for each character, has brute force protection, it's open source GPL and is totally self-contained - no need for SQL databases, PEAR, or anything beyond PHP and GD!
Captcha Home Page : http://www.puremango.co.uk/cm_php_captcha_script_113.php
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