A captcha that uses images instead of garbled text

This plugin adds helpers for the YinXiangMa CAPTCHA API

Define questions and answers in a YAML file and validate your models with a single line of code. No more captchas or other stupid tricks.

Form protection with simple captcha calculations.

Repackaged visualCaptcha's backend service, including translation and minor modification. Mainly for private use. Everything still belongs to original author: emotionLoop. ...

This version include two important page 'Contact' and 'Register' with the 'Math-Captcha' method submit for prevent hacker attack.

Simple negative captcha for Rails