GNU+Linux Humor

Sadly, with the way the patent system works, I don't think any software is completelly free of them. Even the Linux kernel has been accused in the past of having encumbered stuff.

It's still possible that the reason Google scrapped JXL was to boost AVIF, since Google likely has more control over AV1 development. But I don't think it was because of patents. Even Firefox has a lot of resistance for some reason to implement JXL... I think the problem is that AV1 being a standard for video that the browsers already support makes it very easy for them to support AVIF without too much of a dependency... and once they add it, they become more reluctant to add another new generation standard for the same thing, despite JXL being the technically superior format.

I think the reason AV1 has a section about patents in the Wikipedia is because one of the points of that format was to try and protect it against patent litigation... and the sad truth is that there's no 100% sure way to guarantee that any new standard is not violating some patent... According to that same article, the reason why AV1 might not be safe is not so much because of AOM's patents but because of the patents from external unknown third parties that the standard might be infringing. That's why there's a risk, no matter what the AOM group does. As the wikipedia puts it, whether the standard is truly free from royalties it's "Impossible to ascertain until the format is old enough that any patents would have expired (at least 20 years in WTO countries)".