Aaaargggh :-)

Skickat från min iPhone

> 24 Jul 2014 kl. 19:49 skrev Larry Gritz <[email protected]>:
> 
> The fun with PNG never seems to end.  And by "fun", I mean a hot poker in the 
> eye.
> 
> 
>> On Jul 24, 2014, at 1:20 PM, Mikael Sundell <[email protected]> wrote:
>> 
>> 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
> 
> --
> Larry Gritz
> [email protected]
> 
> 
> 
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