I have a few AVIF files. I can view them in Firefox, but I want to be able to open them in some image viewer/editor, and eventually convert them into another graphics format.
On Ubuntu Forums, I found an old thread about AVIF format support in Ubuntu. It was mentioned in that thread that updating gThumb to newest version from Ubuntu Handbook PPA should provide AVIF support in gThumb.
I added that PPA and updated gThumb to version 3.12.8 (it updated several other packages as well, I provide the full apt log below), but gThumb is still unable to display AVIF images, contrary to what the thread author wrote in the forum post: "Just updating with that PPA, not bothering to install anything new, fixed AVIF for existing apps such as Image Viewer and Nautilus." Not for me however.
What's interesting, the newly installed gThumb is able to save an image (opened initially in different format of course) as AVIF (and that AVIF file is properly opened eg. by Firefox), but cannot reopen that file again.
What can I do to make gThumb open AVIF files as well? I use Ubuntu 20.04.
Here's the full log from apt of what has been installed/updated from the PPA:
Install: libx265-192:amd64 (3.4-0sergeyd3.2~20.04.1, automatic), libjxl:amd64 (0.6.1~ppa1~focal, automatic), libaom3:amd64 (3.4.0-1~ppa1~focal2, automatic), libdav1d5:amd64 (0.8.1-0build1~20.04, automatic)
Upgrade: gthumb:amd64 (3:3.8.0-2.1ubuntu0.1, 3:3.12.4-0focal1), gthumb-data:amd64 (3:3.8.0-2.1ubuntu0.1, 3:3.12.4-0focal1), libheif1:amd64 (1.6.1-1build1, 1.11.0-0build5~focal), libde265-0:amd64 (1.0.4-1build1, 1.0.8-0build1~20.04)
