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From: etaylor@wilkins.iaims.bcm.tmc.edu (Eric Taylor)
Newsgroups: comp.windows.x
Subject: Re: Zooming
Message-ID: <2631@gazette.bcm.tmc.edu>
Date: 7 Nov 90 15:47:40 GMT
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Reply-To: etaylor@wilkins.iaims.bcm.tmc.edu (Eric Taylor)
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You can't do this explicitly in X.

The VERY easiest method is as follows:

	Assume original image I1 with dimensions m x n
	Assume new image I2 with dimensions M x N

	Each pixel I2(x,y) = I1(x * m / M,y * n / N)

This is a good first try.  Better algorithms
	utilize smoothing for enlarging images
	and averaging for shrinking images.  These alogorithms,
	however, assume a sophisicated color scheme for 8
	bit machines.
--
					Eric Taylor
					Baylor College of Medicine
					etaylor@wilkins.bmc.tmc.edu
					(713) 798-3776