Ubuntu color management and DisplayCal error

Software
1

I’m profiling my monitor with the latest DisplayCAL on Ubuntu 19.10.

At the end of the process I get this error message:

screenshot_2020-05-27_13-52

I have googled it and on the DisplayCAL support forum the suggestion was that I needed xiccd; I installed it, rebooted but it doesn’t seem to be running (checked with ps -ef | grep xiccd) so the error msg is still there if I run again DisplayCAL.

Now, apart from understanding how to run xiccd (I do have a /etc/xdg/autostart/xiccd.desktop file as suggested in Display Color Profiling on Linux), I’m not even sure if I need this. Is this required by DisplayCAL? Is this xiccd needed at the Ubuntu/Gnome level? What does it do anyway? (I’m sorry, I have read for hours pages upon pages of docs on DisplayCAL and color profiling in lInux in general but I struggle to make a summary of what I need).

I have checked with darktable-cmstest and apparently everything is fine:

(base) 15:05:30 aadm@c64:~$ darktable-cmstest 
darktable-cmstest version 3.0.2
this executable was built with colord support enabled
darktable itself was built with colord support enabled

primary CRTC is at CRTC 0
CRTC for screen 0 CRTC 1 has no mode or no output, skipping
CRTC for screen 0 CRTC 2 has no mode or no output, skipping

DP-1-2-1	the X atom and colord returned the same profile
	X atom:	_ICC_PROFILE (967352 bytes)
		description: SW2700 #1 2020-05-27 12-20 D6500 2.2 F-S XYZLUT+MTX
	colord:	"/home/aadm/.local/share/icc/SW2700 #1 2020-05-27 12-20 D6500 2.2 F-S XYZLUT+MTX.icc"
		description: SW2700 #1 2020-05-27 12-20 D6500 2.2 F-S XYZLUT+MTX

Your system seems to be correctly configured
(base) 15:05:32 aadm@c64:~$

I have also checked the Ubuntu preferences and again, the profile is correctly installed and I see differences when I swithc color management on and off:

screenshot_2020-05-27_15-14
screenshot_2020-05-27_15-14763×583 40.8 KB

So the big question is: should I just ignore the error msg above since it looks like everything is working correctly?

The secondary question (not required but nice to know) is about xiccd? Is this supposed to be an integral part of the color management system in Ubuntu? Something required only by DisplayCAL and if so, why it does not get installed together with argyllCMS when you first launch DisplayCAL?

2

I should add that I’ve read this article: Display Color Profiling on Linux

…and specifically the section on xiccd where it says:

First we’ll need to start xiccd (in the background), which detects your connected displays and adds it to colord‘s device inventory […]

…but as this article was written a few years back, it is still unclear to me if this is somehow surpassed by the current state of Ubuntu.

Also the article explicitly says that “colord and xiccd [are for] a more sophisticated setup” (and what I want is a basic setup!).

3

Xiccd is a bridge between x11 and colors. It enumerates your monitors to colord.

At least on Plasma, not sure about gnome, there is kde-colord, which does the same thing

4

gnome-settings-daemon already works with colord to apply color profiles in Gnome. You should not run xiccd in Gnome. It’s only for other desktop environments without support for color management such as XFCE, LXDE.

5

alright! thanks for that! So you happen to know why DisplayCAL gives me that error at the end of profiling? Or if I should be worried? (as I said above, despite the error everything seems to be working just fine).

6

Sorry I don’t use Gnome so I don’t know. But as long as the profile is applied correctly (which seems to be true in your case), I guess it’s fine to ignore that warning.

I just checked on my computer and although I used xiccd (with LXDE), I still get that warning. But my profile is loaded just fine.