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compjinx
03-14-2002, 08:09 PM
are there any other GOOD compression formats? I know of ZIP, and all that but are there any others that are better?

Prelude
03-14-2002, 08:20 PM
http://www.wotsit.org/search.asp?s=archive

-Prelude

compjinx
03-14-2002, 08:31 PM
but like, what are the pros and cons of these? are they all pretty much the same? do some work better on some file types? which one of these would be good for backing up large 300meg files?

to make a long question short: any reccomendations?

tim545666
03-14-2002, 10:57 PM
You can make a zip and make a rar of that and on and on and it keeps compressing.

$null
03-14-2002, 11:02 PM
Originally posted by tim545666
You can make a zip and make a rar of that and on and on and it keeps compressing.

not a 100% correct there... there is a limit you can only compress certain file types so much... and once it is a zip compressing it to the rar form will have minimal benifits...

tim545666
03-14-2002, 11:03 PM
I've done it before and it worked fine for me.

compjinx
03-14-2002, 11:20 PM
are any of the ones Prelude found any good?

alex
03-15-2002, 08:11 AM
Hi!

rar, arj and zip are good archivers, capable of storing multiple files. But not free software (only the un-archivers are freely available, but the compression algorithm is proprietary and you must have a license to use the compression software). The rar format has some special compression algorithms for multimedia files. They are very good but rarely used. Also, rar has an option to generate recovery-data for very important backups. If the archive is partially damaged (designed to handle unreadable sectors on floppies/harddisks), it should still extract the data without problems.

gzip cannot store multiple files, but compresses equally well as the zip format. Combined with tar utility it makes a good archiver, well accepted in the unix world. Both programs are free software. bzip2 is also a free single-file compressor, but much better than gzip. Most linux-systems have bzip2 installed, but for some reason it is not yet well-supported on proprietary unices.

In terms of compression ratio, the ranking usually (this depends on the types of files used of course) is, from worst to best: zip, tar/gzip, arj, tar/bzip2, rar. Although tar/bzip2 and rar are very close.

Hope this helps...

Justin W
03-15-2002, 08:20 AM
But not free software (only the un-archivers are freely available

Except for this little beauty. (http://www.zdnet.com/downloads/stories/info/0,10615,80815,00.html) ;)

compjinx
03-15-2002, 11:16 AM
Thank you guys, this really helps.