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Date: Tue, 9 Feb 2010 11:05:18 -0600 (CST)
From: Bob Friesenhahn <bfriesen@simple.dallas.tx.us>
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To: Richard Nolde <richard.nolde@cybox.com>
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Cc: Tiff Listserve <tiff@lists.maptools.org>
Subject: Re: [Tiff] Comparing images to detect transmission errors
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On Tue, 9 Feb 2010, Richard Nolde wrote:

> However, the conversion to fax may modify the image resolution depending
> on your faxing system. Standard faxes are 96 lines per inch and Fine
> Faxes are 196 lines per inch. (Or something close, I don't have the spec
> handy.)  There are now much higher resolution options but you would need

If the images are a different size, then they could be resampled using 
an appropriate filter algorithm to produce two images with equivalent 
resolution.  Then more ordinary image comparison algorithms could be 
used.

Direct byte-wise or pixel-wise comparisons would not work unless the 
image is the same resolution.

Bob
--
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/
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