XnView Software

XnView: MP 1.3.1 64bits
OS: Windows 64bit (21H1), display resolution 3840x2160, win scaling 150%

Suggestion
Improve Image Compare tool with Image differencing feature.

Online examples:
https://www.textcompare.org/image/ has some nice settings
https://www.diffchecker.com/image-diff/
https://online-image-comparison.com/
Some of them also have cool representation modes: slider, fade

I support this request.

Related:

• XnView forum
  • Free JPG reduction service
  • Compare more than 4 images, show diffs
  • Basic understanding of "JPEG Quality"?
• xbee @ SourceForge
  • DiffImg
• JMNCO
  • ImageComparator

Qt Blog: Understanding Different Image Comparison Algorithms

Scooter Software: Beyond Compare → Picture Compare

• https://www.scootersoftware.com/images/PixCompare.png
• https://i.stack.imgur.com/OnlUR.jpg
• youtu.be/AKsbjFX4GN8

I do agree too, as the way it is now you just can tell
mouse from elephant...

Thinking on comparing images there are two use cases I
come upon from time to time:

1st case:
Both images seem to be identical but I would like to know
if there is some not so obviously change, or I want to
assess the difference in their quality.

2nd case:
Both images show the same thing,
but are not only geometrically different (shifted, rotated, resized),
but also have different colors, lightning, contrast etc.
The geometrical difference is objected at this thread:
viewtopic.php?f=60&t=44186
The "contents-matching" of the geometrically matched images
(to be exact: the intersection of them)
can be done by matching the curves of the channels.
Manually (very labourisly etc.) or by alg.
Hugin https://en.wikipedia.org/wiki/Hugin_(software)
for example has an (open source) component for this.

Both cases (matching now assumed):
The assessment of the differences by a simple flickering,
"wiper control" of the images etc.
and/ or the generating of arithmetical diff and switching
to R,G,B,H,S,L and an enhancement slider should do.

2nd case:
If I would like to have "best of both worlds" and combine
the better (or additional) part of each image
(Which means actually a kind of "extreme stitching"),
this could be done now.

Man, this would a fine thing to have!
Supporting building quality images.
Would spare a lot of work, and even simple to use.

As XnViewMP seems to be a one man show,
maybe Pierre could deliver and propose an API
that such a method should have...

For those who come here looking for a solution, I use the following temporary fix. Open the two images in two different tabs. Simply switch between the tabs quickly. Any difference usually pops up since it is easier to see temporal changes.