[Coco] JPEG, GIF, and patents...

[Steve Bjork]

At 07:29 PM 4/27/2004 -0400, you wrote:
>   I was wondering if I could save myself a short patent search if someone
>happened to have the patent number for the "best" JPEG and GIF patents.  I
>understand that gif is Lempel-Ziv compression, but don't know anything
>about JPEG.  I'm not too bad with patents either...
>          - Aaron

As for the LZW patent . . .

The Unisys LZW patent expired in the United States on June 20, 2003. The 
Canadian LZW patent will expire on July 7, 2004. Corresponding patents in 
the United Kingdom, France, Germany and Italy will expire on June 18, 2004. 
The Japanese LZW patent will expire June 20, 2004. If you live in a country 
where Unisys' LZW patent is no longer valid, none of the following applies 
to you, except perhaps as a warning about what happens when politicians who 
can't successfully program a VCR are permitted to make laws governing 
technology. These expiry dates were supplied by Unisys' web page.

You are in the clear after July 7 of this year.

As for JPEG, Forgent Networks, an Austin, Tex.-based video networking firm, 
has laid claim to one of the fundamental technologies underlying the World 
Wide Web. Even more significantly, the firm has already convinced two 
firms, including Sony Corp., to pay millions of dollars in royalties.


What the patents cover
The patent in question is No. 4,698,672, titled "Coding system for reducing 
redundancy", approved in 1987 and assigned to Compression Labs Inc., a 
Forgent subsidiary. The patent specifically references patent No. 
4,302,775, "Digital video compression system and methods utilizing scene 
adaptive coding with rate buffer feedback", also assigned to Compression 
Labs but in 1981. Neither patent specifically contains the acronym "JPEG", 
although it stands for "Joint Photographic Experts Group", the organization 
which standardized JPEG through the International Standards Organization in 
1990.

Most of the talk about these patents are from about two years ago and they 
run out 2006 or so.

PNG is patent free, so far.

By the way, all information was easily found by just doing a search on "GIF 
Patent" or "JPEG Patent" using Yahoo or Google  search engines.

Steve Bjork