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