uprightdiff - 1.4.0-1+b7 main

This utility examines the differences between two images.
It produces a visual annotation and reports statistics.
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It is optimised for images which come from browser screenshots.
It analyses the image for vertical motion, and annotates connected
regions that have the same vertical displacement. Then it highlights
any remaining ("residual") differences which are not explained by
vertical motion on a pixel-by-pixel basis.