Daniel Pocock wrote:
Steve Underwood wrote:
Daniel Pocock wrote:
On Sat, Sep 25, 2004 at 11:57:54AM -0500, Eric Wieling wrote:
On Sat, 2004-09-25 at 07:24, Daniel Pocock wrote:
However, the distribution of the g729 libraries themselves are almost certainly infringing.
Then why can you download the G729 source code from the ITU for free?
Where? All the links I see require you to be a member or pay money.
http://www.itu.int/rec/recommendation.asp?type=items&lang=e&parent=T-REC-G.729-199603-I
You can get the complete protocol and a working example at http://www.uspto.gov, no registration required. Search for G.729 and you get 297 results - the original patent is the very last one in the list.
The very nature of patent legislation is that the technology in question has to be made available to the public for purposes of education and further research.
_using_ the technology without a license may be an infringement, but downloading it for the purpose of study or research is perfectly legitimate.
If I go to www.uspto.gov and search for G.729 I get zero results. That is what I would expect. Why would patents mention G.729?
Answer a) you need to use the patent search form, not just the 'search' box at the top of the page
Answer b) (Why would patents mention G.729) Because G.729 is a technology, not a written piece of work.
Written works (like source code and books) are copyrightable. Technology (ideas) are patentable. A piece of source code that implements a patented technology is copyrighted by the person who wrote the code and patented by the person who invented the technology.
It is quite possible to have two completely different source implementations of the same technology. Eg, I might write a G.729 encoder in C and you might write one in Java. Each of us holds copyright over our respective implementation, but both utilise the technology described in the same patent.
The important point as far as Asterisk is concerned is that documents and source code which explains a patent can be distributed without violating the patent, provided that the copyright holder has given permission - you only have to pay if you compile and use the code.
I know perfectly well how patents work, and you don't patent a spec. You patent key techniques used in that spec. In the case of the patent you found, it is "CS-ACELP speech compression system with adaptive pitch prediction filter gain based on a measure of periodicity". I was suprised to find they actually mention G.729 at all in a patent. We never used to do things like that. Still, as long as you avoid wording that ties anything to the G.729 spec. itself, I can't seen any particular reason not to mention G.729.
All you have referred to is one patent. What about all the others relevant to G.729. You just found one. :-)
You have used Intel's code, which in turn uses much of the code in the ITU spec. The ITU spec. may be freely downloaded. However, the source code explicitly says you have no right to use that source code for anything other than forming a bit exact reference model.
Regards, Steve
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