I seems as if Nuke writes data with associated alpha in PNG files, according to the spec it's not valid:
http://www.libpng.org/pub/png/spec/1.2/PNG-DataRep.html "The color values stored for a pixel are not affected by the alpha value assigned to the pixel. This rule is sometimes called "unassociated" or "non-premultiplied" alpha. (Another common technique is to store sample values premultiplied by the alpha fraction; in effect, such an image is already composited against a black background. PNG does not use premultiplied alpha.)" This causes the PNGReader to associateAlpha(…) on already alpha multiplied data. Did anyone else experience this problem? Mikael
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