XnViewMP Linux - Image Comparison buggy

Bugs which have been reproduced by a second user or the developer, or features to do

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emanek
Posts: 5
Joined: Sat Nov 08, 2025 6:12 pm

XnViewMP Linux - Image Comparison buggy

Post by emanek »

Hello,

on Ubuntu 24.04 (x64), i7-1260P, 32 GiB RAM, image comparison stopped working maybe a half year ago. (It had been working fine before that.)

Now in 1.9.5 it partially works again for small images but after closing the program, XnView process keeps running, 100% utilizing one CPU core and must be killed manually. (It's actually two processes.)

Comparing larger images (e.g. 24 megapixel) doesn't work at all. Nothing is displayed and the process must be killed.

Please look into it if you can. It's a very useful feature. Thank you.

Code: Select all

2025-11-08T19:34:39.382869+01:00 emcmp XnView.desktop[8747]: ### CRASH ###
2025-11-08T19:34:39.388504+01:00 emcmp XnView.desktop[8747]: message repeated 3509 times: [ ### CRASH ###]
2025-11-08T19:34:39.388508+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1269.32 ] error    3 BadWindow    request   20 minor    0 serial 467700: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388510+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1269.32 ] error    3 BadWindow    request   20 minor    0 serial 467701: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388512+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1269.32 ] error    3 BadWindow    request   20 minor    0 serial 467702: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388514+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1269.32 ] error    3 BadWindow    request   20 minor    0 serial 467703: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388515+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1269.32 ] error    3 BadWindow    request   20 minor    0 serial 467704: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388517+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1269.32 ] error    3 BadWindow    request   20 minor    0 serial 467705: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388519+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1269.32 ] error    3 BadWindow    request   20 minor    0 serial 467706: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388521+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1269.32 ] error    3 BadWindow    request   20 minor    0 serial 467707: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388522+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1269.32 ] error    3 BadWindow    request   20 minor    0 serial 467708: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388524+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1269.32 ] error    3 BadWindow    request   20 minor    0 serial 467709: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388526+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1269.32 ] error    3 BadWindow    request   20 minor    0 serial 467710: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388528+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1269.32 ] error    3 BadWindow    request   20 minor    0 serial 467711: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388529+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1269.33 ] error    3 BadWindow    request   20 minor    0 serial 467713: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388531+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1269.33 ] error    3 BadWindow    request   20 minor    0 serial 467714: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388533+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1530.70 ] error    3 BadWindow    request   20 minor    0 serial 494642: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388535+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1530.70 ] error    3 BadWindow    request   20 minor    0 serial 494643: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388537+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1597.89 ] error    3 BadWindow    request    2 minor    0 serial 525026: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.388550+01:00 emcmp XnView.desktop[8747]: ### CRASH ###
2025-11-08T19:34:39.395161+01:00 emcmp XnView.desktop[8747]: message repeated 3509 times: [ ### CRASH ###]
2025-11-08T19:34:39.395166+01:00 emcmp /usr/libexec/gdm-x-session[2105]: [  1616.14 ] error    3 BadWindow    request   20 minor    0 serial 548924: "BadWindow (invalid Window parameter)"
2025-11-08T19:34:39.395181+01:00 emcmp XnView.desktop[8747]: ### CRASH ###
2025-11-08T19:34:51.203612+01:00 emcmp XnView.desktop[8747]: message repeated 5598896 times: [ ### CRASH ###]
2025-11-08T19:34:51.203687+01:00 emcmp systemd[1]: systemd-hostnamed.service: Deactivated successfully.
2025-11-08T19:34:51.203811+01:00 emcmp XnView.desktop[8747]: ### CRASH ###
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xnview
Author of XnView
Posts: 47575
Joined: Mon Oct 13, 2003 7:31 am
Location: France

Re: XnViewMP Linux - Image Comparison buggy

Post by xnview »

you means comparing 2+ images side by side?
Pierre.
emanek
Posts: 5
Joined: Sat Nov 08, 2025 6:12 pm

Re: XnViewMP Linux - Image Comparison buggy

Post by emanek »

Yes.
But I've solved the problem by deleting

Code: Select all

~/.config/xnviewmp/
directory.
Probably there was something wrong in the configuration impairing only this side by side comparison.
emanek
Posts: 5
Joined: Sat Nov 08, 2025 6:12 pm

Re: XnViewMP Linux - Image Comparison buggy

Post by emanek »

But please wait with closing this ticket.
I've changed only a couple of things and the problem is back. I'll try to find the settings that causes the problem.
emanek
Posts: 5
Joined: Sat Nov 08, 2025 6:12 pm

Re: XnViewMP Linux - Image Comparison buggy

Post by emanek »

Found it. It's this setting causing the problem:
xnviewbug.png
When set to None or Bilinear (default), everything is fine.

With other options (like Bicubic, Lanczos etc.) only small images display in comparison view and XnView process must be killed afterwards. Larger images don't display at all.

I think (but I'm not 100% sure) that the side by side comparison used to work even with Lanczos3 (my preference) in older versions.
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user0
XnThusiast
Posts: 2857
Joined: Sat May 09, 2015 9:37 am

Re: XnViewMP Linux - Image Comparison buggy

Post by user0 »

can confirm an issue (win11)
1. set zoom-in to Bicubic, Spline32 or Lanczos3/4
2. select 2 images (original + its copy) in Browser and press SHIFT+C
3. select A/B and zoom-in to >200%
image(s) will be black
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xnview
Author of XnView
Posts: 47575
Joined: Mon Oct 13, 2003 7:31 am
Location: France

Re: XnViewMP Linux - Image Comparison buggy

Post by xnview »

:bugconfirmed: Thanks to your detailed description I can reproduce the problem.
Pierre.
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xnview
Author of XnView
Posts: 47575
Joined: Mon Oct 13, 2003 7:31 am
Location: France

Re: XnViewMP Linux - Image Comparison buggy

Post by xnview »

This problem is supposed to be fixed in XnView MP 1.9.9. Please check and confirm the bug fix here.
Pierre.
emanek
Posts: 5
Joined: Sat Nov 08, 2025 6:12 pm

Re: XnViewMP Linux - Image Comparison buggy

Post by emanek »

Unfortunately, still does not work in 1.9.10 x64 Linux.
Comparing two quite small images + Lanczos 3 or Lanczos 4 downsampling freezes the application. No problem with Bilinear.

Not a really big issue (I can live with Bilinear), but I can't confirm this as resolved.
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xnview
Author of XnView
Posts: 47575
Joined: Mon Oct 13, 2003 7:31 am
Location: France

Re: XnViewMP Linux - Image Comparison buggy

Post by xnview »

emanek wrote: Fri Jan 16, 2026 11:38 pm Unfortunately, still does not work in 1.9.10 x64 Linux.
Comparing two quite small images + Lanczos 3 or Lanczos 4 downsampling freezes the application. No problem with Bilinear.
i can reproduce the crash on linux only
Pierre.
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user0
XnThusiast
Posts: 2857
Joined: Sat May 09, 2015 9:37 am

Re: XnViewMP Linux - Image Comparison buggy

Post by user0 »

xnview wrote: Mon Jan 19, 2026 7:10 am i can reproduce the crash on linux only
looks fixed on windows