POV-Ray : Newsgroups : povray.binaries.tutorials : Check(er) Your Gamma : Re: Check(er) Your Gamma Server Time
17 May 2022 19:47:49 EDT (-0400)
  Re: Check(er) Your Gamma  
From: Ive
Date: 6 Nov 2009 03:45:11
Message: <4af3e217$1@news.povray.org>
A quick note about Photoshop and it's PNG support:

I'm using Photoshop since version 4.0 and currently CS3 (still not sure 
about updating to CS4) and every version had broken PNG support in one 
way or another. Usually the gamma and sRGB chunk was ignored, some 
version did completely mess up 16 bps images and CS3 writes colorimetric 
chunks (color primaries and whitepoint) but 'forgets' to add the gamma 
chunk (and it claims when saving to PNG that this file format does not 
support any metadata - a plain lie because PNG even supports XMP, the 
way that is favored by Adobe itself for storing metadata).
Given the long time and that PNG is a quite simple format it seems not 
that far fetched that PNG support is broken deliberately - as some 
people claim - but I fail to see the reason behind it.

clipka wrote:
|...]
> (BTW, to scale a gamma-encoded image without messing up the colors, I 
> can highly recommend IC. It does properly convert the image to linear 
> color space before resampling.)

Thanks for the advertising ;)

-Ive


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