Color profile changes after using "montage" on PNG files

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Arancaytar
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Color profile changes after using "montage" on PNG files

Post by Arancaytar »

I've got some map tiles that I want to scale down and recombine by a factor of 2x2. The command I'm using goes like this:

Code: Select all

montage z0/0,0.png z0/1,0.png z0/0,1.png z0/1,1.png -geometry 256x256 z1/0,0.png
This works correctly, but even though the input images images look identical in Gimp and Firefox, and the output image looks correct in Gimp, the colors of the output image are somehow warmer in Firefox. The output also seems to change from 8-bit PNG to 16-bit PNG.

This album shows the input and output images, as well as screenshots for gimp and Firefox side by side.

Is there anything I can do (either to the input images or the montage options) that fixes these colors?
snibgo
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Re: Color profile changes after using "montage" on PNG files

Post by snibgo »

Please provide a set of input files and the created output file that shows this colour change.
snibgo's IM pages: im.snibgo.com
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fmw42
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Re: Color profile changes after using "montage" on PNG files

Post by fmw42 »

If your resulting image has no profile, it will show differently on different browsers. So you should add a profile (sRGB) to your result. You may have to do that in a separate convert command. I do not know if montage permits the setting of profiles.

Please always provide your version of IM and platform.
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