2010.02.09 17:05 "Re: [Tiff] Comparing images to detect transmission errors", by Bob Friesenhahn

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