gz@spt.entity.com (Gail Zacharias) (09/06/90)
Stuffit 1.5 uses 14-bit LZW compression. A rule of thumb about LZW is that each additional bit gives you about a 10% decrease in size. I'll bet that Stuffit Deluxe just uses 16-bit LZW compression. So much for great leaps forward in compression technology. I have an MPW tool that does 16-bit LZW. I don't do user interfaces though. If somebody wants to do a stand-alone user interface, you're free to use my compression code. You can sell it, shareware it, or give it away, I don't care, as long as you make the format public. -- gz@entity.com ...!mit-eddie!spt!gz Now let's all repeat the non-conformist oath.
tempest@walleye.ecst.csuchico.edu (Kenneth K.F. Lui) (09/06/90)
In article <5385@spt.entity.com> gz@spt.entity.com (Gail Zacharias) writes:
Stuffit 1.5 uses 14-bit LZW compression. A rule of thumb about LZW is
that each additional bit gives you about a 10% decrease in size. I'll
bet that Stuffit Deluxe just uses 16-bit LZW compression. So much for
great leaps forward in compression technology.
There is no indication that StuffIt Deluxe's Better algorithm
uses 16-bit LZW coding. First, it is too slow--witness
MacCompress. Second, if you do a get info on a file that has
been compressed using Better, it'll say something like LZ
Huffman. The algorithm may be more of an LZ-variant that uses a
huffman step. This algorithm is implemented, in a similar way,
in LHarc for the IBM PC-family of computers.
With all of this bickering about using a public archiving system
for the net, why not use tar and compress?? That's about as
public as you can get! There's source, and you can port all you
want...although I'm sure they've been ported already. :-) :-)
:-)
Ken
--
_____________________________________________________________________________
Kenneth K.F. Lui | Other paths you can use: tempest@csuchico,
tempest@csuchico.edu | tempest@{cscihp|walleye}.csuchico.edu
__________________________|__________________________________________________hammen@ddsw1.MCS.COM (Robert Hammen) (09/08/90)
I've stayed out of The Great Compression Wars up until now. I'd like to bring up a couple of issues that no one else has (to my knowledge). 1) Of the three contenders (StuffIt Deluxe, Compacter, and DiskDoubler), StuffIt Deluxe is the only one that supports the BinHex 4.0 format, which is of obvious importance to net.users (call me backward, but I still do the binhexing on my Mac - it's easier to save the description from the header of a file that way). 2) With all of the clamoring for "open" file formats, why don't we (the net community as a whole) develop our own compression/decompression program? It may also allow us to develop a new format to succeed BinHex 4.0 (which is not all that efficient, in any case - atob and btoa would be better). I'd be willing to help coordinate a group of people interested in working on such a project (I'm not really a Mac programmer, though, so I wouldn't be able to do any coding). If we are unable to come up with a consensus on what to do, I recommend that we stick with the BinHex 4.0 and StuffIt 1.5.1 formats, respectively. (A consensus? On Usenet? What an interesting, and impossible, idea!). ///////////////////////////////////////////////////////////////////////////// / Robert Hammen | Macintosh enthusiast & publishing guru, looking for a job / / hammen@ddsw1.mcs.com | 70701.2104@compuserve.com | GEnie: R.HAMMEN / /////////////////////////////////////////////////////////////////////////////
outer@sq.sq.com (Richard Outerbridge) (09/09/90)
In article <5385@spt.entity.com> gz@spt.entity.com (Gail Zacharias) writes: >Stuffit 1.5 uses 14-bit LZW compression. [....] I'll >bet that Stuffit Deluxe just uses 16-bit LZW compression. So much for >great leaps forward in compression technology. You'd lose your money: so much for ignorant flaming. Ray tried several types of compression as candidates for Deluxe's "Better" algorithm, but what he settled on is not 16-bit LZW.
kap1@phyllis.math.binghamton.edu (Dietrich Kappe) (09/14/90)
In article <5385@spt.entity.com> outer@sq.sq.com (Richard Outerbridge) writes: >>Stuffit 1.5 uses 14-bit LZW compression. [....] I'll >>bet that Stuffit Deluxe just uses 16-bit LZW compression. So much for >>great leaps forward in compression technology. > >You'd lose your money: so much for ignorant flaming. Ray tried >several types of compression as candidates for Deluxe's "Better" >algorithm, but what he settled on is not 16-bit LZW. Promises, promises. Until I see the code, its 16-bit LZW. But I guess there is scant chance of you backing up your claim. :-) --Dietrich-- ______________________________________________________________________________ | | | | kap1@phyllis.math.binghamton.edu | "Suspicion is the badge of | | | base-born minds, | |_______________________________________| And calculation never | | | understands." | | "My opinions are entirely my own, | -Virginia Moore | | for who else would want them?" | Tragic Conclusions | | | | ______________________________________________________________________________