OpenCaptcha is a php script designed to dynamically create a captcha image in .png form. It uses a randomly chosen background to start with, then chooses a random string of a randomly chosen length, color, size, font, and orientation. Then it adds randomly coloured and placed lines to create an image that computers can't easily interpret. With OpenCaptcha, you can easily use your own custom backgrounds and fonts to make it fit in better with your overall site design.
