On Thu, May 5, 2011 at 12:48 PM, Paul Hartman <paul.hartman+gen...@gmail.com> wrote: > On Wed, May 4, 2011 at 6:06 PM, Sebastian Pipping <sp...@gentoo.org> wrote: >> Hello! >> >> >> I stumbled upon the article >> >> Gamma error in picture scaling >> http://www.4p8.com/eric.brasseur/gamma.html#Use_a_correct_software >> >> recently. I was actually pointed to it be some tool applying the proper >> algortihm. I think it was command line. > >> Especially as I don't trust ImageMagick with files that matter I would >> love to find (or re-find) a command line tool that properly handles >> Gamma when resizing images. Needs be free software. Anyone? > > ImageMagick works. I downloaded the Dalai Lama photo from that page > and converted it by doing: > > convert -colorspace sRGB gamma_dalai_lama_gray.jpg -scale 50%% -set > colorspace sRGB gamma_dalai_lama_gray50.png > > And the resulting image is correct.
I will add the disclaimer that it *appears* correct to me. It is not a solid grey image like the "bad" examples on that page. I don't fully understand what that page is talking about and most of it was a whooosh over my head. :)
