PLEASE DO NOT USE THIS GEM.
USE MODERN IMAGE LIBS OF RAILS.
This project is based on https://github.com/phatworx/easy_captcha.
This gem is for an ancient project.
add to Gemfile
gem 'easy_captcha_rails', require: 'easy_captcha'
use the "easy_captcha-0.6.5.patch" file to patch the original gem.
This project is released under the MIT license.