A simple and fast image captcha generator that uses opencv and memcached.

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

Russian Post tracking toolset, consisting tracking form bot (since Russian Post is too retarded for normal API) and captcha solver/recognizer.

dongsx

Antispam helps prevent spam in your Rails applications by checking against DNS blacklists and spam-prevention databases. It has two core features: (1) IP-based spam detection using Project Honey Pot to block known spammers automatically, and (2) content-based spam detection using Defendium’s mach...

Simple negative captcha for Rails

AntiCaptcha api ruby wrapper

Antigate (Decode captcha service) wrapper for Ruby

This gem provides integration with TrustCaptcha for Ruby applications, offering CAPTCHA verification with a focus on security and privacy.

Quick little arithmetic plain-text captcha

A gem to generate captcha pictures.

Description of RailsCaptcha.

Captcha generator for rails

This plugin adds helpers for the YinXiangMa CAPTCHA API

Implements view helpers for the ASIRRA CAPTCHA system for Rails-based websites

Helps humankind with simpler captchas

Form protection with simple captcha calculations.

create captcha for api based project

LoyalSimpleCaptcha is available to be used with Rails 3 or above and also it provides the backward compatibility with previous versions of Rails.

Merb plugin that provides resource access rate limits and captcha'ing