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

Captcha based on encyrpting and decrypting user data by mathematical operation

NO LONGER MAINTAINED AND NOT RECOMMENDED, AS BOTS ARE ABLE TO RESOLVE CAPTCHAS BETTER THAN HUMANS. Based on Login Attempts check if captcha is necessary. It stores a permanent cookie and uses a table for tracking login requests.

Integrate the AreYouAHuman.com CAPTCHA alternative human verification into your Ruby/Rails application

This library can help you create a captcha in your terminal application, which may be damaged by a large influx of requests.

Death by Captcha Ruby implementation (HTTP API)

Helps humankind with simpler captchas

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

Description of RailsCaptcha.

Simple lib to generate a math_captcha to prevent spammers in form. Supports localization.

create captcha for api based project

MVC based Math, Logic Captcha

HumanDetector is a friendly logic captcha for Rails the doesn't require any external system dependency (e.g. external captcha API connections). It uses a simple question that any 7 or more years old human can understand, but that a spambot will not be able to answer. This Gem supports Ruby v1.9.2 and Rails 3.0.x.

A simple image captcha gem

This is a gem wrapper for tiny captcha in C with no dependencies.

dongsx

Gem that uses RuCaptcha API to solver any type of captcha

这是一个验证码生成器。基于rucaptcha。本人只是将他的源码拉下来。为我的网站进行适配。因为我不使用sesion.id