How does WebFX do what it does? It's simple, actually!

INPUT	You use the form on this page to give WebFX the address of an image, and to tell it what effect you want it to do.
DOWNLOAD	WebFX runs Lynx, a simple web-browser, and uses it to download the picture off of the Internet.
DECODE	WebFX then decodes the GIF or JPEG data into "raw" data (using djpeg or giftoppm),
EFFECT	and applies the effect. (The code to do the effects were all written from scratch by yours truly. They were written in C and take advantage of my old 'cgi-draw' drawing library.)
RECODE	WebFX saves the image into a temporary file on the server (using cjpeg to make the JPEGs and "MultiGIF" to make the animated GIFs).
OUTPUT	WebFX then displays a simple web page which includes the temporary file as a graphic.

WebFX totals nearly 5,800 lines of C sourcecode, spanning 16 files. Over 2,700 lines of that make up the main WebFX CGI code.