I have several, self stitched, huge PNG file which always causes XNView MP to crash upon trying to generate a thumbnail. They all roughly share the same dimensions of 23040x35200 pixel (some are 36480 in width).
On a few of them XNView MP creates a mostly black thumbnail with barely visible lines of the original images. On others (those involving alpha channel) the program just crashes upon trying to create a thumbnail. On the other files with black thumbnail it crashes as well after a moment when I click onto them to see them on the preview panel. The crash always happens, even if I open a directory with the single image from the start (like via context menu on the directory)
As the memory consumption of XNView MP goes up to around 3.5 Gigabytes of RAM before it crashes, I assume, that would be the problem.
If needed I can provide such a file without problem. It has a filesize of 432 MB which I can upload onto my own webspace.
For comparison and clarification: Windows Explorer creates a thumbnail within 3 to 5 seconds and showing the correct image contents. There is no thumbnail embedded in the file, so Windows had to read it from the (NVME) disk. I see Windows using the dllhost.exe with a call to thumbcache.dll to do this.
IrfanView also open the file just fine, it just needs some seconds. Image details are these then:
