[FFmpeg-devel] [PATCH] VP8 de/encode via libvpx

[Robert Swain]

On 20 May 2010 11:26, Uoti Urpala <uoti.urpala at pp1.inet.fi> wrote:
> On Thu, 2010-05-20 at 10:12 +0200, Diego Biurrun wrote:
>> On Wed, May 19, 2010 at 02:28:10PM -0400, James Zern wrote:
>> >
>> > --- /dev/null ? ? ? 2010-02-26 16:50:52.000000000 -0500
>> > +++ libavcodec/libvpxdec.c ?2010-05-17 23:46:16.000000000 -0400
>> > @@ -0,0 +1,168 @@
>> > + *
>> > + * ?Subject to the terms and conditions of the above License, Google
>> > + * ?hereby grants to You a perpetual, worldwide, non-exclusive,
>> > + * ?no-charge, royalty-free, irrevocable (except as stated in this
>> > + * ?section) patent license to make, have made, use, offer to sell, sell,
>> > + * ?import, and otherwise transfer this implementation of VP8, where such
>> > + * ?license applies only to those patent claims, both currently owned by
>> > + * ?Google and acquired in the future, licensable by Google that are
>> > + * ?necessarily infringed by this implementation of VP8. If You or your
>> > + * ?agent or exclusive licensee institute or order or agree to the
>> > + * ?institution of patent litigation against any entity (including a
>> > + * ?cross-claim or counterclaim in a lawsuit) alleging that this
>> > + * ?implementation of VP8 or any code incorporated within this
>> > + * ?implementation of VP8 constitutes direct or contributory patent
>> > + * ?infringement, or inducement of patent infringement, then any rights
>> > + * ?granted to You under this License for this implementation of VP8
>> > + * ?shall terminate as of the date such litigation is filed.
>>
>> Ah, so the patent grant only covers this implementation! ?Once we come
>> up with our native and faster decoder, we will be liable again. ?Good
>> job Google!
>>
>> Also note the language about "necessarily infringed" - if Google comes
>> up with some clever tricks to speed up this implementation tenfold and
>> then go on to patent it, you are *not* granted a license. ?You can,
>> after all, implement VP8 the slow way...
>
> Well what else would you expect such a patent license to say? It could
> hardly specify that it'd cover any patent in any code whatsoever as long
> as that code managed to decode VP8 as one of its functions.

This reflects what I was thinking when reading what Diego wrote above.

I guess there could be some kind of patent grant license text in the
specification that is worded such that implementations of the spec
(within reasonable bounds) are granted license to use the patents
covered within it or so. At least, that would make more sense to me
than a license concerning one piece of code addressing what can be
done in other implementations.

I understand and respect Diego's concern about the whole patent issue
though and have no intention of undermining that through this comment.

Regards,
Rob