ATLAS GRAPHICS FILE FORMATS
last modified: K. Eno, 3/8/95

This document states what types of image files can be displayed by the
Macintosh version of the Interactive Atlas program, version 2.1.


PLAIN IMAGES should be stored in raw PICT or PICT2 format, including the
standard 512-byte header area. Saving from programs like PhotoShop in
the normal PICT format should be sufficient; when using Fetch to transfer
files, be sure to use "Raw Data". The names of image files do not matter on
the Macintosh, as long as they are located properly relative to the Index
files that refer to them.

(Note on bit depths: the program can display any PICT file, but performance
greatly depends on the hardware platform. 1-bit images will open fine on a
Mac Plus, but something like a 16- or 32-bit bitmap will open very slowly
on a B&W or 8-bit display like on a Mac II.)

(Note on compression: the PICT Compressor utility or PhotoShop's JPEG option
can achieve 5-fold and better savings on space, which will improve transfer
times for image files coming off CD-ROM or over the network. However, both
these compression methods require the presence of the QuickTime extension on
the user's Macintosh, and can be quite slow on older machines. Testing on all
intended target machine types should precede the decision to use this feature.)


ANIMATIONS are QuickTime files as generated by SimplePlayer or the makemoov
utility on the SGI. When transferring them to the image server, be sure to
use "MacBinary II" option, because both data and resource forks (and the file
type information) are necessary to play the movies, and the Atlas program will
require MacBinary in order to transfer the movie back from the server at all.