Yea my weird steps can make images look like correct linear, in gimp. but after I export it, it can only be displayed correctly in softwares capable of reading embed icc profile, like XnView. In game engine it tragically turn back to dark edges. If I convert to built-in sRGB profile before exporting, the image turn back to dark edges immediately, so I figured out the “copy visible to new image” way, again, not sure if it’s technically right :-//
oh sorry for one more question: is krita’s LSY color mode similiar to gimp’s LCH? I guess the y means y in xyz ref space
The commit id from help shows that your version of 2.9 is not current with default GIMP 2.9 git master.
As you seem to be pretty good at sleuthing out issues, and you understand the difference between linear gamma and perceptually uniform RGB, it might be nice if you figure out how to build GIMP from git on Windows. This way you’d always have access to the latest code, and could help debug issues in the current code. @partha 's website has build instructions for Windows.
Yes, that looks correct. Problems you might (or might not) encounter include file-format-specific export issues and issues with internal TRC changes sometimes getting out of sync.
Grayscale also is subject to gamma issues, the classic case being drawing a gray gradient. See the first image on this page:
You are working with gaming which afaik tries to emulate behavior of real light, and real light falls off linearly, so you probably don’t want gamma artifacts in your grayscale images.
Whatever works. You could ask on IRC (irc://irc.gimp.org/gimp) or on the gimp dev mailing list (GIMP - Discuss). But the first question you are likely to get is “Which commit number and which OS?” followed by “Can you update to the latest code and see if the problem is still there?”
No, they are not the same. See HSL and HSV - Wikipedia, and also read the rest of the article, esp. the section on disadvantages.
It means Y (luminance) from XYZ, or luma/Y’ if the color space is not encoded linearly. xyz is not the same as XYZ - the case matters. “z” in xyz = 1 - (x + y).
If you are curious, equations for converting between xyY , XYZ, LAB, and LCH are here - click on the “math” link: http://brucelindbloom.com/
Hi very thanks for your time.
sorry I misspelled, I mean krita has HSY mode, not HSL, or HSV or HSI. Seem like the term Luma on wiki page. From krita doc they claimed it’s much better than other, giving user “true luminosity” but intuitively bind to color–sounds like RGB luminosity in gime cce. I’ll do more test, hoping krita can be a useful backup, partially.
That’s a bit challenging for me because I may have problem accessing github. But I’m finding a guide like this for a long time(removed from partha’s website links), thanks a lot