[Theora] Independent implementations?

[Christoph Lampert]

<40F2BDE1.3080103 at gmx.net>
Message-ID: <Pine.LNX.4.58.0407132048120.23066 at login.math.uni-bonn.de>

On Mon, 12 Jul 2004, Maik Merten wrote:
> Kyungjoon Lee wrote:
> > So my question is, is it alright to create and distribute a Theora
> > codec which isn't based on the Theora code from Xiph.org? If VP3 code
> > is in Theora, and VP3 is patented, does that mean that you can't
> > write/modify a non-Xiph Theora codec without infringing on On2's
> > patents?
>=20
>  From FAQ:
>=20
> "Q. Isn't VP3 a patented technology?
> Yes, some portions of the VP3 codec are covered by patents. However, the=
=20
> Xiph.org Foundation has negotiated an irrevocable free license to the=20
> VP3 codec for any purpose imaginable on behalf of the public. It is=20
> legal to use VP3 in any way you see fit (unless, of course, you're doing=
=20
> something illegal with it in your particular jurisdiction). You are free=
=20
> to download VP3, use it free of charge, implement it in a for-sale=20
> product, implement it in a free product, make changes to the source and=
=20
> distribute those changes, or print the source code out and wallpaper=20
> your spare room with it.
> For more information, check the VP3 Legal Terms on the SVN page"
>=20
> Although you may "infringe" on On2=B4s patents for VP3 when implementing=
=20
> Theora this is not a problem as On2 gave an "irrevocable free licence"=20
> to all humanity (remember: Patents can only cause trouble if you don=B4t=
=20
> have a license). This licencse is not bound to a specific codebase.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Hm, dont' be too sure. If On2 gave a free license to use their=20
patented technology to "any person who... utilized the On2 VP3 Codec=20
Software...". The complete "VP3 Legal Terms" that the FAQ refers to is:

On2 represents and warrants that it shall not assert any rights relating=
=20
to infringement of On2's registered patents, nor initiate any litigation=
=20
asserting such rights, against any person who, or entity which utilizes=
=20
the On2 VP3 Codec Software, including any use, distribution, and sale of=
=20
said Software; which make changes, modifications, and improvements in=20
said Software; and to use, distribute, and sell said changes as well as=
=20
applications for other fields of use.=20

This e.g. doesn't automatically allows to use patents by On2 in any other=
=20
software than in On2 VP3 Codec software, unless they are changes,=20
modifications or improvements.=20

I would interpret thing in that way that you are _not_ automatically=20
allowed to create a VP3 or Theora clone from scratch. Maybe it's meant in=
=20
a way that should allow it, but I wouldn't rely on it. Usually, legal=20
terms say exactly what they want to be allowed, and don't mean more than=20
they say.=20

Christoph