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From: schwarze@isa.de (Jochen Schwarze)
Newsgroups: comp.lang.postscript
Subject: Halftoning Algorithm
Message-ID: <3245@isaak.isa.de>
Date: 17 Nov 90 15:19:53 GMT
Sender: news@isaak.isa.de
Organization: ISA GmbH, Stuttgart, FRG
Lines: 17


I am wondering how the postscript halftoning algorithm works. It seems
to be much more than simply painting one halftone dot after the other.
Rather than varying dot size in proportion to gray values the dot
shape seems to change according the gray values of the adjacent
pixels. I've studied Digital Halftoning by R. Ulichney, but I couldn't
find references pointing in that direction.

Can anybody enlighten me? Or is this a proprietary and/or patented
and/or secret technique by Adobe?

Thanks.
--

Jochen Schwarze                     Domain: schwarze@isa.de
ISA GmbH, Stuttgart, West Germany   UUCP:   schwarze@isaak.uucp
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