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From: okeefe@cs.Buffalo.EDU (Paul O'Keefe)
Newsgroups: comp.graphics.visualization
Subject: apE: image depth and colormaps
Message-ID: <1991Mar4.185030@cs.Buffalo.EDU>
Date: 4 Mar 91 23:50:30 GMT
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I need some help understanding the relationship between
image depth and colormaps in apE.

I using apE on a SparcStation with an 8-bit color X11 server.
This machine also has a Taac board which has 24-bit color.
I was hoping to export apE images as 24-bit Sun rasterfiles
then import them into Taac format and see them in true color.

I beleive that apE is able to generate true color images since:

1) the apE function "img_export" can output a apE image in numerous
   formats including 24-bit Sun rasterfiles

2) the image produced by Comer Duncan and shown in Pixel Magazine
   certainly appeared to be true color.

However, the apE manual says that all colormaps have 245 entries.

Question: how does this jive?

Is the image computed in true-color and the 8-bit colormap is just
a subset used for display within apE?

Paul O'Keefe
okeefe@cs.buffalo.edu