robjung@world.std.com (Robert K Jung) (04/20/91)
Concerning the capabilities of the new ARJ 2.00 release, there are a few facts that should be clarified. ARJ 2.00 has two compression methods. Each has been designed to compete against a particular product. ARJ -m1 (the default) typically provides better compression and better speed than LHA 2.1x. ARJ -m2 provides better compression and slightly slower speed than PKZIP 1.10. On average, ARJ -m2 is slightly slower than PKZIP 1.10. On databases and formatted user manuals, ARJ -m2 is often faster than PKZIP. On binary files and runfiles, ARJ -m2 is significantly slower than PKZIP. ARJ has been designed with a general purpose compression algorithm. Since PKZIP's compressor is pre-computed and tailored to IBM PC data, it will be very difficult to build a general compressor to match PKZIP's speed on compression and extraction. The main goals of ARJ are to provide as much practical compression as is possible on an IBM PC machine and as many features as practical. robjung@world.std.com (Robert K Jung)
c60b-1eq@e260-1f.berkeley.edu (Noam Mendelson) (04/21/91)
In article <1991Apr20.052556.3247@world.std.com> robjung@world.std.com (Robert K Jung) writes: >ARJ has been designed with a general purpose compression algorithm. >Since PKZIP's compressor is pre-computed and tailored to IBM PC >data, it will be very difficult to build a general compressor to >match PKZIP's speed on compression and extraction. ARJ 2.00 comes very close, although it lags behind in decompression. >The main goals of ARJ are to provide as much practical compression as >is possible on an IBM PC machine and as many features as practical. How about UN*X compatibility? There are ZOO, ARC, LHARC, and ZIP (although not by Phil Katz, of course) programs available for UN*X systems, however I haven't seen any source code for ARJ. The question is: is ARJ designed for portability? If not, then it should be optimized to deal with PC-specific data; otherwise, it should be ported to other OS's. -- +==========================================================================+ | Noam Mendelson ..!ucbvax!web!c60b-1eq | "I haven't lost my mind, | | c60b-1eq@web.Berkeley.EDU | it's backed up on tape | | University of California at Berkeley | somewhere." |