Tool for "breaking up" graphic files for web pages

[Charles P. Hobbs]

There are a number of web pages, like http://www.aafla.org, that consist
of several graphic files that have been split apart. They load into table
cells, giving the appearance of a single graphic. But they have the
flexibility of multiple files (e.g. only parts can be animated, as opposed
to the whole file, saving file size and download time) 

Does anyone know of a tool that allows one to "cut apart" a graphics file 
like this? (I know Photoshop, etc. can do this, but one often has
difficulty counting pixels, getting the files to line up correctly, etc.)

What I envision is a program that will 
a. load the graphics file
b. allow one to draw "lines" on the graphic, indicating where it is to be
split
c. execute a command to "split" the file and save all the subfiles.

Anything like that exist yet?

Thanks!


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Charles P. Hobbs                          __  __     ____  ___       ___ ____
transit at primenet.com                     /__)/__) / / / / /_  /\  / /_    /
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