From owner-freebsd-hackers Thu Sep 26 15:12:46 1996 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id PAA18784 for hackers-outgoing; Thu, 26 Sep 1996 15:12:46 -0700 (PDT) Received: from mail.cdsnet.net (mail.cdsnet.net [204.118.244.5]) by freefall.freebsd.org (8.7.5/8.7.3) with SMTP id PAA18730 for ; Thu, 26 Sep 1996 15:12:40 -0700 (PDT) Received: from mail.cdsnet.net (mail.cdsnet.net [204.118.244.5]) by mail.cdsnet.net (8.6.12/8.6.12) with SMTP id PAA19269; Thu, 26 Sep 1996 15:11:04 -0700 Date: Thu, 26 Sep 1996 15:11:03 -0700 (PDT) From: Jaye Mathisen To: Julian Assange cc: meditation@gnu.ai.mit.edu, hackers@freebsd.org Subject: Re: bzip vs gzip In-Reply-To: <199609261347.XAA02455@suburbia.net> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-hackers@freebsd.org X-Loop: FreeBSD.org Precedence: bulk Seems to me I recall reading in the original posting of bzip, that the author warned against commercial usage of it because of potential patent problems. Ah, here it is: >From sewardj@cs.man.ac.uk Mon Sep 9 22:44:21 PDT 1996 Article: 2129 of comp.os.linux.announce From: Julian Seward Newsgroups: comp.os.linux.announce Subject: bzip 0.21, a statistical data compressor Date: Mon, 09 Sep 1996 08:14:55 GMT Lines: 43 Approved: linux-announce@news.ornl.gov (Lars Wirzenius) Message-ID: NNTP-Posting-Host: localhost [stuff removed] The command-line interface is very similar to that of gzip, so you can use bzip as a drop-in replacement for gzip, if you like. For more information, and the distribution, point your browser at: http://www.cs.man.ac.uk/arch/people/j-seward/index.html Because of possible patent infringement problems, you should not use bzip for commercial purposes. On Thu, 26 Sep 1996, Julian Assange wrote: > Date: Thu, 26 Sep 1996 23:47:44 +1000 (EST) > From: Julian Assange > To: meditation@gnu.ai.mit.edu, hackers@freebsd.org > Subject: bzip vs gzip > > > [http://www.cs.man.ac.uk/arch/people/j-seward/index.html] > > BZIP compresses the usual 14 files from the Calgary Corpus to an > average of 2.340 bits per byte, which is within about 5% of the best > known results, and considerably better than the more widespread > LZ77/LZ78-based compressors [of which Gzip seems to be amongst the > best]. Memory consumption is controllable, never exceeding 8,100 k > for compression, and 5,400 k for decompression, even for very long > files. You can tell BZIP to use less memory via command-line flags, > giving minimum uses of 1200 k for compression and 600 k for > decompression. This makes it usable on 8 meg and even 4 meg machines; > compression is still better than Gzip. For some kinds of > highly-redundant files, Bzip has been observed to do strikingly (3 > times) better than Gzip. > > BZIP is an infinite-context statistical compressor, using preliminary > run-length coding of the input, the Burrows-Wheeler block-sorting > transformation, Fenwick's structured coding model, run-length coding > of zeroes in the MTF codes, and a DCC95-style arithmetic coder. > > BZIP is distributed under the GNU General Public License, version 2, > which means you can copy, use and redistribute it freely. It should > run on any 32-bit platform with an ANSI C compiler; I myself have > made successful builds, without modifying the sources, on: > i386/i486-Linux1.2, i386/i486-Linux2.0, i386/i486-Windows95, > Sparc-SunOS4, Sparc-Solaris2, SGI-Irix, HP-HPUX and HP-NetBSD. In > practice BZIP should work without modification on any 32-bit > GNU-supported target. I have also heard that an earlier version runs > ok on Alphas; successful builds are also reported for a Mac > Powerbook, and an Acorn R260 running RISC iX. > > BZIP has been heavily tested: the volume of data compressed in the > final validation tests exceeds 1700 megabytes in 41000 files, with > the longest file 425 megabytes long. This version, 0.21, is > completely compatible with the .bz files created by version 0.15 -- > 0.21 differs only in being faster, more portable and offering the > "-c" flag.