[FFmpeg-devel] AC3 audio encoding license questions

Jeremy Greene jeremy
Sat Nov 13 03:09:44 CET 2010

We contacted Dolby almost 2 years ago and have had some of the most
bizarre interactions I've ever had. Bizarre in that they just didn't
seem motivated to take our money. Unless you happen to exactly fit into
one of their existing market models, mainly some kind of encoder chip,
you go down an alice in wonderland tunnel. As to whether or not they are
giving you a license for the technology or the right to use their name
they just won't clearly answer.

So, I was hoping someone else had gone down the various tunnels and
figured out what the answer is. Getting legal advice is a possible
option, but without some kind of direction, it could get pretty
expensive very fast.


-----Original Message-----
From: ffmpeg-devel-bounces at mplayerhq.hu
[mailto:ffmpeg-devel-bounces at mplayerhq.hu] On Behalf Of Michael
Sent: Friday, November 12, 2010 6:45 PM
To: FFmpeg development discussions and patches
Subject: Re: [FFmpeg-devel] AC3 audio encoding license questions

On Fri, Nov 12, 2010 at 06:20:02PM -0500, Jeremy Greene wrote:
> Hi,
> Not sure this is the correct list, but the question is: does anyone 
> know if the use of AC3 as defined in ATSC A52B(AC3) standard requires 
> a license as long as it's stated just that way (no use of the Dolby 
> trademark etc.)? It would seem that any patent relating to what's in 
> the standard would have expired by now. But I have done a ton of 
> searching and there's really no information that I can find. And
asking dolby...
> well...

iam not a lawyer but naively i would in this situation ask dolby for a
license, ask them how much it costs and what patents exactly one gets
licenses for. Then check the expire dates on these patents, if they are
expired already or if they have been submited after the standard was
published then you shouldnt need them. (and for additional entertainment
you can sue them for trying to scam you into obtaining unneeded licenes)
But ultimately this is a question for a lawyer and not a developer like
me so you should definitly ask a lawyer about this

Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Asymptotically faster algorithms should always be preferred if you have
asymptotical amounts of data

More information about the ffmpeg-devel mailing list