Wide gamut colour on KDE?

Brainstorm
,
1

I have observed that the wide colour gamut functionality on my KDE Plasma session (Wayland) appears to be partially non-functional. I ran a test and obtained the following results:

  • Pass: Brave, Okular, VS Code, MPV, KolourPaint, Feh, Konsole & Yakuake (via viu).
  • Fail: Gwenview, Falkon, Firefox, and all of the above applications when run as Flatpaks.

Krita required me to disable ‘Use system monitor profile’ and manually enforce ‘Display P3’ before it passed the test.

I am curious to what extent my distribution choice might be affecting this. Gwenview is the most significant failure here, particularly as it has explicit settings for colour management, none of which seem to resolve the issue.

In System Settings → Display, I attempted to set the colour profile to both the built-in default and the ICC profile provided by the monitor manufacturer; neither changed the test results.

Could someone discuss the current state of colour management on KDE ? Would anyone be willing to run the same test to confirm my findings?

To perform the test, please search the web for ‘wide gamut test page’. You should find a page featuring a large red square with the letter ‘W’. You can right-click and save this image locally, which is what I used for testing.

2

DigiKam also required me feeding it the monitor ICC profile before passing the test.

3

Such a test image can only tell you whether or not the app’s color management is broken for sure, but not actually if it’s working properly. An app that ignores the image’s embedded color profile will “pass” the test, but it’s not presented correctly. You’d need to either measure the resulting color, or compare with some app you know for sure is working correctly.

None of Okular, KolourPaint, Konsole, Yakuake, Gwenview, Falkon, Firefox, DigiKam have non-sRGB color management support. Neither does Brave atm, Chromium’s color management support is broken in versions < 144. Krita’s support for Wayland color management is also not released yet, it will come with version 6.0.

Gwenview’s “color management” option should be hidden, it doesn’t do anything nowadays. It was only implemented for X11, and it wasn’t exactly done well (tbf, that describes X11 color management in most apps). It’s technically possible to implement proper non-sRGB color management in it, but it’s quite difficult because of how the app is written. Afaik the situation is similar for Okular.