Path: utzoo!utgpu!attcan!uunet!husc6!mailrus!eecae!flynn
From: flynn@eecae.UUCP (Pat Flynn)
Newsgroups: comp.lang.postscript
Subject: Compressing Postscript gray-scale images
Summary: How about compressing 8-bit gray-scale imagery?
Keywords: gray scale hex postscript compression
Message-ID: <12107@eecae.UUCP>
Date: 29 Sep 88 15:53:28 GMT
Reply-To: flynn@cpsvax.cps.msu.edu (Patrick Flynn)
Organization: Amrcn. Abbrvtn. Soc'ty.
Lines: 17

There has been some recent traffic here about compressing bitmap images
in Postscript to mimimize the transmission time over the serial line.
Does anyone have any good ideas on compressing images that are *non-binary*
(more than two gray levels)?  We print out reams of 8-bit gray-scale images
here, and one 512x512 image will occupy the printer
for roughly 10 minutes at 9600 baud (we use the `image' operator, hex codes
for the intensity values, 2 bytes/pixel, so at 1000 characters/second,
we're talking 500+ seconds not counting overhead).

Has anyone written such a beastie? Maybe something that unpacks a binary
file of gray levels that has been compress(1)'ed?

Thx!
__
Pat Flynn, Computer Science, Moo U. (Michigan State University)
flynn@cpsvax.cps.msu.edu FLYNN@MSUEGR.BITNET flynn@{eecae,msudoc,frith}.UUCP
New Punk Band: "George Bush and the Thousand Points of Light."