[speex-dev] regarding CELP/ACELP/others patentes

[Jean-Marc Valin]

> As I understood the problem is in ACELP algorithm which AMR uses in 
> 6.7kbs mode. Other modes use CELP. He can disable this mode and this 
> will allow him to donÿt break law. Am I right?

No. AMR (like other proprietary codecs) is full of patents and I'm
pretty sure most of the modes actually use ACELP (otherwise, they'll
just be patented by someone else).

> And second question: how can I get full list of patented algorithms used 
> in AMR standard? Could you point me to some resource?

No idea, but I don't think it's realistic to go after each patent (there
are tons), so if you really want to use AMR, you have to pay the
"middleman" that will sell you the whole patent package. I don't think
there's any other (legal) way to go. That's especially true for AMR (you
mean AMR-NB, not AMR-WB, right), which is a collection of codecs that
were already patented before going into the AMR standard.

Otherwise, there's Speex ;)

        Jean-Marc


-- 
Jean-Marc Valin
http://www.xiph.org/~jm/
LABORIUS
Université de Sherbrooke, Québec, Canada


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