France Telecom claims patent on Opus, gets rebuffed, with technical analysis of claims Options

[Garf]

France Telecom made an announcement that they have a patent which they believe applies to Opus:
http://www.ietf.org/mail-archive/web/codec...t/msg02955.html

Given that they heavily oppose Opus, there's little reason to believe they'll want to license it royality-free:
http://www.ietf.org/mail-archive/web/codec...t/msg02958.html
http://www.ietf.org/mail-archive/web/rtcwe...t/msg05106.html

Mozilla and Xiph published a press release today with their analysis of the patent. It's quite interesting IMHO because it actually dives into the technical details of the claim:
https://hacks.mozilla.org/2013/02/defending-opus/

They conclude that the claim is bogus.

[Dynamic]

Looks that way, though while I have some patent experience, I am not a lawyer. And if anyone nervous of getting even close wanted to be REALLY safe they have only to implement the simple patch suggested in that 'defending opus' link to the encoder's SILK layer code (one line change) which has negligible effect on PESQ scores around 12kbps, and virtually none from 14 to 16kbps upwards according to the graphs.

It's possible they want to make the declaration of a potentially relevant patent 'just in case' it's applicable. It COULD be applicable to an encoder that is not identical to the reference encoder and does manage to implement claim 1 of that patent in a way that still decodes properly.

Although, come to think of it, the part about computing the difference between the synthetic signal and the original speech signal is not what Opus is trying to do (one of its innovations), so it would probably be pretty stupid to compute that, but it might be possible to infringe if you really tried to.

The IETF rules requires declarations of IP that could be relevant from companies involved, so it might be nothing more than somebody realising that it's an option to implement an Opus encoder that way.

It's good to see Mozilla keep us informed so soon and make a completely convincing case that this particular patent cannot possibly apply to a decoder (because by definition a decoder doesn't have access to the speech input signal).

I notice that the Opus-codec.org license page mentions a lawyer's opinion of the disclosed IP (but doesn't make it absolutely plain what date the opinion was stated - given that companies may acquire IP in the future or discover potential relevance of other IP.

... external counsel Dergosits & Noah has advised us that Opus can be implemented without the need to license the patents disclosed by Qualcomm, Huawei, or France Telecom.

This post has been edited by Dynamic: Feb 6 2013, 22:56

[IgorC]

France Telecom is a big player on audio compression area.
Jumping on the train of patent trolls as the last remedy means that Opus is a serious deal and causes a money lost for big commercial organizations.

As a simple user I'm very happy with Opus because it's the first format that support full band 48 kHz and such a low delay 20-25 ms and lower with a great quality at relatively low bitrates. Well, LD-AAC isn't bad at all but it requires somewhat higher bitrates for the same quality. It's unbeleivable, none of ITU standards have full band (up to 48 kHz) format with such low delay.
Check that out http://en.wikipedia.org/wiki/Comparison_of_audio_formats

Do better instead of playing patents games.

This post has been edited by IgorC: Feb 7 2013, 00:22

[Porcus]

BIG$$ corporate lawyer FUD is by itself a problem, unfortunately. I guess the next step is that they threaten anyone who considers releasing a usable encoder.

[_if]

I'm curious about the back story of France Telecom's objections to Opus. This is the first I've heard of it.

[Garf]

I'm curious about the back story of France Telecom's objections to Opus. This is the first I've heard of it.

Educated guess: They hold patents on the codecs that Opus replaces (G722, AMR, AMR-WB). Check the link I gave above, that should give you some idea.

[Garf]

BIG$$ corporate lawyer FUD is by itself a problem, unfortunately. I guess the next step is that they threaten anyone who considers releasing a usable encoder.

Xiph releases binaries, and obviously they're more than willing to fight it in court.

Also note that Opus *is* known to be covered by royality-free patents with retaliation clauses. If you sue anyone for using it, you'd better not be using Skype, Firefox or Chrome anywhere in your organisation.

[Garf]

The IETF rules requires declarations of IP that could be relevant from companies involved, so it might be nothing more than somebody realising that it's an option to implement an Opus encoder that way.

It's always possible to create an encoder that violates any random patent, so declaring IPR just because someone might infringe it doesn't make any sense. That's the job of the patent office

The claim made in the IPR statement was that you couldn't possibly use Opus without infringing the patent. This is false.

[wswartzendruber]

Wait a sec, you can be retaliated against if you use Skype and sue for Opus patents?

[Dynamic]

Wait a sec, you can be retaliated against if you use Skype and sue for Opus patents?

If you look at the license on http://www.opus-codec.org/license/ it summarises it simply at the top then describes it in detail. Essentially it's a defensive use of patents with regard to any third party and a measure against patent-hiding by the Opus contributors themselves to avoid a situation where somebody with a relevant patent waits until loads of people are using it then starts to sue for infringement.

Skype at the moment doesn't include Opus, but they're working on it, so you MIGHT get away with using Skype under its current license until they upgrade and incorporate the Opus licensing and then be unable to use Skype when they do. Firefox ships with Opus support already, as does Google Chrome (though not supporting opus in the HTML audio element by default). If you use these products and sue anyone for Opus use, they can countersue for your unlicensed use of patents relevant to Opus. Likewise, you'd be unable to use anything with WebRTC support in future unless you go to great lengths to disable Opus support.