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From: DeadHead@cup.portal.com (Bruce M Ong)
Newsgroups: comp.graphics
Subject: shrinking a bitmap by 3
Message-ID: <32071@cup.portal.com>
Date: 25 Jul 90 22:37:41 GMT
Distribution: na
Organization: The Portal System (TM)
Lines: 14


I am writing a program that would shrink a bi-level bitmap by three.
The original image is 1728 pixels wide (fax) and has 2050 scanlines. Does
anybody know a quick algorithm to do this? My original approach is to 
take 3 bits at a time and if there are two black bits, then the resultant
bit will be set, otherwise the resultant bit is a white bit. The image is
not shrunk vertically.  However, this is tooo slow...

any pointers, text books, etc., would be much appreciated...
 
thanks -

bruce
deadhead@cup.portal.com