LZW Compression       


Information Theory Accomplishment | 1983

IBM researchers: Mark Wegman, Victor S. Miller

Where the work was done: IBM T.J. Watson Research Center

What we accomplished: Lempel-Ziv-Welch: One of the most standard compression formats.  While it's commonly known by the Unisys inventors, Lempel, Ziv and Welch, the work was done independently at IBM with IBM's work filed at the patent office earlier. Unisys got a lot of publicity for its legal actions with anyone who used GIF format files, whereas IBM took a much lower key approach to the use of the patent. The IBM work contained a number of compression ideas not in the LZW work as well and could achieve better compression rates.

This was also one of the first important software patents allowed after the Supreme Court enabled software patents.

The ideas were used not only for image compression but are used in most telephone modems.

Related linksPatent with full description of the ideasWikipedia Page

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