[Theora] Independent implementations?

[Freun Laven]

<Pine.LNX.4.58.0407140933330.24645 at login.math.uni-bonn.de>
Message-ID: <002501c469bb$5268feb0$33389c3f at computername>

From: "Christoph Lampert"

> What you posted is a software license, right? It grants you the right to

Correct.

It was in the source package that I downloaded right after On2 made the vp32
codec open source and they did the vp3.com web site.

Here's the md5.  (Just in case you want to know which version of source I
have.)

a903299ee014cd81ebbddd22fe12ffbf *vp32.tar.gz


It's kind of odd that nowhere on the Theora site is there a copy of the
original vp32 code package from On2.com/vp3.com or its license.  Or any of
the bug fixed versions of vp32 that were done in the past couple of years.

And it's kind of odd that the vp3.com site itself no longer even has the
original source or even a copy of the license!  Or talks about what patents
in particular are involved.

That's why I posted the license that came with the code.  I seem to be one
of the few people who actually downloaded the original vp3.com package and
are still in this forum.


> use, modify, sell etc. a piece of software, which is the VP3 source code.
> Basically, it allows you to do almost everything with the program, unless
> you change its behaviour to not work with VP3 format anymore.

Probably not even that restrictive.  The Theora bitstream and codec behavior
is not the same as vp32.  It can do the old format, just to retain backwards
compatability, but Theora itself is beyond vp32.

So apparently you can go beyond vp32.  Maybe still provide classic vp32
compatability, but you can apparently make a new advanced version that is
not itself compatable with vp32.

> But this document doesn't say a thing about other sourcecode than what it
> came with. It doesn't give a license to use the patented algorithms with
> anything else than the source or (permitted) modifications of.

Sorry about that...  I thought it did cover that.  Obviously I'm not the
best at reading licenses.

It does, at least, give you the right to use that code and make it into
something very very different.  They don't say you have to actually keep the
original code intact.  It can be modified so much that the original code is
pretty much gone.

As long as it was originally based on the original code, then you shouldn't
have a problem, even if the final code ends up with none of the original
code left.


> Christoph
>
> P.S. Btw, it there a list of what patents in Theora On2 actually owns?

Not that I ever remember seeing.

I don't remember ever seeing that on the vp3.com web site, which was where
vp32 was officially released as open source.

You can always contact On2.com / vp3.com and ask them directly.  Probably be
safer that way.