Eric Brasseur writes "Every picture scaling software I could test makes a gross error: the gamma of the picture being scaled is not taken into account. This makes that for example a pixel that should be at 50% brightness can get only 22% brightness. Depending on the kind of picture, the damage can be quite important. I wrote a page to explain the whole: www.4p8.com/eric.brasseur/gamma.html"
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