Hello, I'm the Daala tech lead.

One of the things that made Opus a success was the contributions of others. We certainly don't have a monopoly on good ideas. We'll take pieces of Daala and stick them in Thor and pieces of Thor and stick them in Daala, and figure out what works best. Some of that experimentation has already begun:

https://github.com/cisco/thor/pull/8

https://review.xiph.org/874/

https://www.ietf.org/proceedings/93/slides/slides-93-netvc-5...

Because none of us have a financial incentive to get our patents into the standard, we're happy to pick whatever technology works best, as long as we end up with a great codec at the end. Hopefully NETVC can replicate the success of Opus this way.

It's this kind of awesome attitude that makes me so happy whenever I look into a Xiph project. I certainly did not mean to imply that the efforts of the org in OP should be moved to Daala and that competing projects are a bad thing; far from it! Rather, I was just voicing my support for a similar project that has had some great progress so far.

You all have done a great job in the past and I'm always on the edge of my seat to see what incredible things you will do. Keep up the rockin' work!

Yeah, we're going to have to start arguing on what to name the hybrid soon, since 'Vopus' is already taken.

Brainstorming fun names combining "Thor" and "Daala" reminded me of the Robert E. Howard villains "Thulsa Doom" and "Thoth-Amon". :)

I propose Kollóttadyngja!

I hope you could have a comprehensive write-up about how codec works.

your article, such as this http://people.xiph.org/~xiphmont/demo/daala/demo1.shtml is the best codec introduction I could find online, but still I couldn't follow, say, the deblocking part.

there doesn't seem to be a book covering this area.

Is Thor based on similar principles to Daala (i.e. like lapped transforms) to make it useful for merging?

And unrelated question, what will be the name of the merged codec? I hope it won't remain as NetVC, as that name is awful.

According to the spec, Thor is a more traditional block-based codec with quadtree subdivisions in the vein of H.264 and forward.

Beyond that the design is rather conservative and different from Daala's "start over from scratch" methodology. It doesn't look like the two would be poised to merge directly a-la Opus at this point, but rather to be mutual test beds and borrow and exchange unencumbered ideas that work well.

I see, thanks.

Apparently, as part of the NetVC[0] effort Daala has started experimenting with Thor tech and innovation, Thor's been added to AreWeCompressedYet[1] and they looked into integrating Thor's motion compensation and its constrained low-pass filter into Daala during the IETF93 NetVC hackaton[2] a few weeks ago.

[0] https://tools.ietf.org/wg/netvc/

[1] https://arewecompressedyet.com

[2] https://www.ietf.org/proceedings/93/slides/slides-93-netvc-5... (PDF)

I'm betting on Daala and Thor. Both the teams involved are motivated by the same goal to make a royalty free codec. I think the odds are good that the IETF standards process will result in combining the best ideas of Daala and Thor and reviewing them from and patent point of view. If the guys doing VP10 wanted to work with us in an open way, that would be great too.

Opus was actually a similar combination of two codecs, CELT from Xiph.org and SILK from Skype.

So similarly, there are now two projects, Daala from Xiph and Thor from Cisco, which are both preliminary but being worked on in the same group, so hopefully the best parts can be taken from each to produce a new, better open codec.

There was a great talk about Daala at Linux.conf.au 2015 (https://www.youtube.com/watch?v=Dmho4gcRvQ4). It has both general, and technical information about Daala, so it's well worth a watch.

looks interesting, Opus is great