[kuschku]

Sadly, Google is trying to patent AV1, and only giving a patent license to users of its implementation.

If you want to build your own implementation, either to implement it in hardware, or to release it under a different license, then you’ll be fucked.

[TD-Linux]

The AOM patent license covers any implementation of the format. It additionally covers the reference implementation, because the encoder may use techniques that aren't part of the bitstream format, and it's important to grant rights to those too.

http://aomedia.org/license/patent/

[indolering]

Indeed, the whole point of Daala and AV1 is to do a really good job on the IP front so as to make it much harder for patent trolls to hold everyone hostage [0].

0: https://www.youtube.com/watch?v=u3Yc5Hn9bhQ

[boxerab]

Yes. They have applied for a patent on ANS and video compression - ANS is one of the biggest advances in lossless encoding in the last 10 years. The inventor wants to keep it freely available, has helped Google for three years to incorporate ANS in AV1 - their reward is to try to patent his invention. More details here:

https://news.ycombinator.com/item?id=14583691

[shmerl]

That doesn't make sense really. Do you have a source for it?

[wolf550e]

https://encode.ru/threads/2648-Published-rANS-patent-by-Stor...

[shmerl]

403 Forbidden

Anyway, as TD-Linux said above, any implementation is allowed.

> 1.1. Patent License. Subject to the terms and conditions of this License, each Licensor, on behalf of itself and successors in interest and assigns, grants Licensee a non-sublicensable, perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable (except as expressly stated in this License) patent license to its Necessary Claims to make, use, sell, offer for sale, import or distribute any Implementation.

> 2.6. Implementation. “Implementation” means any implementation, including the Reference Implementation, that is an Encoder and/or a Decoder. An Implementation also includes components of an Implementation only to the extent they are used as part of an Implementation.

http://aomedia.org/license/patent/

I really have no idea what "to the extent they are used as part of an Implementation" means though.

[derf_]

> I really have no idea what "to the extent they are used as part of an Implementation" means though.

Say, for example, you make a chip that does motion search acceleration and you want to sell it to people who do both AV1 and H.264 encoding. You'd be covered for any patents included under this license to the extent the chip was used for AV1 encoding, even though you didn't make a complete encoder. To the extent someone wanted to use it for H.264 encoding, your or they would still have to negotiate a separate license (just as you would have if AV1 didn't exist).

Source: I helped write this license.

[shmerl]

I see, thanks! The language itself sounds eerily circular :)

[derf_]

That's intentional. We want to cover components that are themselves used in other components, recursively up the whole supply chain, as long as they're ultimately used for AV1.

[redtuesday]

Someone archived the page, so for the people getting a 403: http://archive.is/362lF