The custom_captcha plugin is an example of how to make changes to the CAPTCHA script. Use this plugin to randomize the background image, or add additional fonts.

We encourage you to modify this plugin to add your own fonts / images to the CAPTCHA.

See the code comments for more information.

Thanks to the folks who created the open source Gentium fonts (http://scripts.sil.org/gentium) we have included with this plugin. These are distributed under the OFL license (see OFL.txt attached).