okLAB colorspace of G'MIC-QT？

Software G'MIC
#1

I have some favorite filters in GMIC-QT, such as “curves”, “decompose channels” and so on. They provide many channels to choose from.

Now I think oklab is an ideal model, and there seems to be oklab code in GMIC. Is it expected to be added to the above filter in the future?

In addition to oklab and oklch, the author also made okhsv and okhsl. I hope they get attention, too.

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#2

It exists!

#@cli rgb2oklab
#@cli : Convert color representation of selected images from RGB to Oklab.
#@cli : (see colorspace definition at: <https://bottosson.github.io/posts/oklab/> ).
#@cli : See also: ''oklab2rgb''.
rgb2oklab :
  e[^-1] "Convert color representation of image$? from RGB to Oklab."
  foreach {
    split_opacity to_rgb[0] /[0] 255
    f[0] "
      l = cbrt(0.4121656120*R + 0.5362752080*G + 0.0514575653*B);
      m = cbrt(0.2118591070*R + 0.6807189584*G + 0.1074065790*B);
      s = cbrt(0.0883097947*R + 0.2818474174*G + 0.6302613616*B);
      [ 0.2104542553*l + 0.7936177850*m - 0.0040720468*s,
        1.9779984951*l - 2.4285922050*m + 0.4505937099*s,
        0.0259040371*l + 0.7827717662*m - 0.8086757660*s ]"
    a c
  }

To transform from oklab2oklch do, use lab2lch. To find the inverse, go from lch2lab to oklab2rgb. Also remember to use srgb2rgb and rgb2srgb. I usually forget.

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