To: news AT daimi DOT aau DOT dk Reply-To: "Markus F.X.J. Oberhumer" Approved: mailtonews AT daimi DOT aau DOT dk Newsgroups: comp.os.msdos.djgpp Path: news.daimi.aau.dk!news.uni-c.dk!news1.global-one.dk!news1.transpac.net!news-stkh.gsl.net!news.gsl.net!news-lond.gsl.net!news.gsl.net!netcom.net.uk!newsfeed.easynet.co.uk!easynet-uk!www.nntp.primenet.com!nntp.primenet.com!swrinde!news.sgi.com!news.mathworks.com!uunet!in3.uu.net!alpine.psnw.com!news.bconnex.net!news.lightlink.com!mv!news2.mv.net!usenet From: "Markus F.X.J. Oberhumer" Subject: LZO 0.22 -- a real-time data compression library Message-ID: <199610010219.DAA25489@osiris.oeh.uni-linz.ac.at> Content-Type: text Content-Length: 2884 Return-Read-To: mfx AT oeh DOT uni-linz DOT ac DOT at Organization: None provided Date: Tue, 1 Oct 1996 02:19:08 GMT Dj-Gateway: from mailing list djgpp AT delorie DOT com To: djgpp-announce AT delorie DOT com Lines: 92 -----BEGIN PGP SIGNED MESSAGE----- ============================================================================== LZO -- a real-time data compression library ============================================================================== Author : Markus Franz Xaver Johannes Oberhumer http://www.infosys.tuwien.ac.at/Staff/lux/marco Version : 0.22 Date : 19-Sep-1996 Availability ------------ ftp://sunsite.unc.edu/pub/Linux/Incoming/lzo-0.22.tar.gz ftp://ftp.switch.ch/mirror/linux/sunsite/Incoming/lzo-0.22.tar.gz Archive size is about 145 kB. What's new since 0.20 --------------------- - added GNU autoconf support (LZO is reported to work under Linux 2.0, HP-UX, AIX and Solaris) - added 'official' LZO benchmark - LZO1X: minor decompressor speedup, added some checks in safe decompressor Introduction ------------ LZO is a data compression library which is suitable for data de-/compression in real-time. This means it favours speed over compression ratio. I named it LZO standing for Lempel-Ziv-Oberhumer. LZO is written in ANSI C. Both the source code and the compressed data format are designed to be portable across platforms, and LZO should work on each architecture that has at least 32 bit integers. Somewhat limited support for 16 bit MSDOS is implemented as well (using 'huge' pointers). LZO implements a number of algorithms with the following features: - Decompression is simple and *very* fast. - Requires no memory for decompression. - Compression is pretty fast. - Requires 64kB of memory for compression. - Allows you to dial up extra compression at a speed cost in the compressor. The speed of the decompressor is not affected. - Algorithm is thread safe. - Algorithm is lossless. Design criteria --------------- LZO was designed with speed in mind. Decompressor speed has been favoured over compressor speed. Real-time decompression should be possible for virtually any application. I expect an implementation of the decompressor in assembler code to run at the third of the speed of a memcpy(). Portability ----------- I have built and tested LZO successfully on the following platforms: i486 - Linux 1.2.6 - gcc 2.6.3 i486 - MSDOS - djgpp v2 + gcc 2.7.2 i486 - MSDOS - emx + gcc 2.7.2 i486 - MSDOS - Watcom C 10.5 (32 bit) i486 - MSDOS - Borland C 4.0 (16 bit) For more information point your browser at: ------------------------------------------- http://www.infosys.tuwien.ac.at/Staff/lux/marco/lzo.html -----BEGIN PGP SIGNATURE----- Version: 2.6.2i iQCVAwUBMkcH7W10fyLu8beJAQGPLQP9HKO7OHJA5dtkButKNki1ITLimP43tPJo v2f7l3beLQwLJZyGjWzcWhSDOdwWMlnTd0R19oZIQ31EsRzRJgbHj2Ze+5hS/TfZ R3m6l/PinCiMzXTidMY4CSAPqyS+Kb3mUjjj26Im//06/L3mUEGjaMGWdlCgS0Ss PAFylL5U5F0= =uOsT -----END PGP SIGNATURE-----