this book will open your eyes
O'Reilly have an enormous reputation to maintain; every tome with an animal on the cover is expected to be full of insight. Well, this monster-titled book is no exception. It starts with the basics of image formats; GIF, JPEG, PNG and MNG are all covered in nasty excruciating detail--on the way giving simple insight the fundamental differences between them. It then progresses to the basics of web image serving, cataloguing a large number of web-based resources for image manipulation libraries. After that the meat course: image manipulation and dynamic serving using GD, ImageMagick and Perl. The author has to be congratulated here on his use of examples; there is no unnecessary CD, the programs are of the 'type, learn and explore' variety--none of them are prohibitively long. After that, a section is dedicated to the Gnu Image Manipulation Program (the GIMP) but focused on the material already covered (the difference between image formats and scripting the GIMP using Perl). The tail end is devoted to client and server-side image maps, ASCII art as textual graphic replacements(!) and an in-context study of PostScript.
The whole book is littered with web references to help you through this enormous topic, just in case you need pointers to more depth.
The area is a much ignored-topic at the moment--if you're involved with web development using Perl, this book will open your eyes. One for the bookshelf, although I suspect it will be some time before the knowledge imparted by books like this actually gets used in commercial development.