PhotoPrint

[Ralf Mardorf]

PS:

I forgot to mention at least some Linux apps aimed for development of
digital photos, that are available by official Ubuntu repositories. I
don't recommend those apps, I just want to name a few.

https://packages.ubuntu.com/lunar/digikam
https://packages.ubuntu.com/lunar/darktable
https://packages.ubuntu.com/lunar/photoflare

Those are just a few apps that came to mind. While I launched or at
least tried to launch them on my Arch Linux install, I noticed that I
should write at least one bug report, if I would care for those Linux
apps.

For editing pixel graphics an alternative to Gimp is Krita.

https://packages.ubuntu.com/lunar/gimp
https://packages.ubuntu.com/lunar/krita

To some extend those can be used to edit photos, too. For GIMP a Lensfun
plugin is available. Krita is missing Lensfun support, but in my
experiences it's a pixel graphic app that gets better and better, while
Gimp gets worse and worse.

https://packages.ubuntu.com/lunar/gimp-lensfun

For HDR imaging separated Linux apps do exist.