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Re: Workaround for compress patent?

>> I wonder if it wouldn't be possible to convert gzip files to compress
>> files without recompressing?  I haven't seen the patent, but it's just
>Umm, gzip and compress are very different algorithms; gzip was
>*written* to avoid the patent (see also "yabba" done slightly before

Gzip wasn't written to avoid the patent...  It is just a completely
different algorithm.  It's actually the same algrithm used in pkzip2.0.

Let's see...  If I remember correctly, it's some kind of sliding-window
pattern matching with shano-fanno optimization...  Or something like

>However, I was under the impression that the
>reason gzip supported "uncompress" was because the patent covered
>compression, not decompression... regardless of the more recent
>unisys/CI$ claims.

This is correct.  Only compression is covered by the LZW patent,
which incidently only covers the "Welch" addition, which just
improves on the storage of the compressed stream generated by

                                 ( bcwhite@bnr.ca )

    In theory, theory and practice are the same.  In practice, they're not.

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