Archaic compression formats

[Failure]

I'm trying to pick a new compression format for the Amix UNIX software I've been building.  One of the things I wanted to do was to stay with formats that can be managed with utilities resident on a stock 2.1 installation, but being prepared to adopt another format if the difference in sizes was truly staggering.

The only archive format that handled links correctly was tar.  For this reason, everything is going to be wrapped in a tar file first.

Here's the results in ascending order.  Below, (A) denotes utilities native to Amix 2.1.

agw@shodan:/srv/nfs/t-elos/export/agw/amix$ du -b * | sort
288284   screen-4.0.3.tar.7z 7zip
393691   screen-4.0.3.tar.gz gzip
394939   screen-4.0.3.tar.lha (A) lha
395064   screen-4.0.3.tar.zoo (A) zoo
411949   screen-4.0.3.tar.lzh (A) lharc
415713   screen-4.0.3.tar.bz2 bzip2
433946   screen-4.0.3.tar.zip (A) zip
532717   screen-4.0.3.tar.z (A) pack
545267   screen-4.0.3.tar.Z (A) compress
587776   screen-4.0.3.tar

bzip2 generally compresses better than gzip, but it takes for-ev-er on my A3000 :-)  I was leaning towards lha at first, but zoo is faster and lha is considered non-free by Debian.  I looked at the license and wasn't enlightened as to why...perhaps it's just not explicit enough?

I think I'm going to use zoo.  Compress is the "traditional" choice but although it's fast the reduction in size is pretty poor in comparison.  Plus, the version of zoo on Amix is the last one, so I can compress the files from my much faster AMD machine with identical output.

Hope this wasn't too pedantic :-)

[trilobyte]

bzip2 generally compresses better than gzip, but it takes for-ev-er on my A3000 :-)  I was leaning towards lha at first, but zoo is faster and lha is considered non-free by Debian.  I looked at the license and wasn't enlightened as to why...perhaps it's just not explicit enough?

I think I'm going to use zoo.

bzip2 is slow as heck indeed.

Lha might be considered non-free because of the patents on the LZW algorithm.  Was it Unisys trying to exploit royalty rights to LZW before its patent ran out?  This was a few years ago.  I could Google it and find the answer, but then again so could you

If you were around back in the day you probably recall that zoo was not an uncommon compression format on BBSes and on the Amiga (and UNIX and...).  I'm surprised to see that it still holds up well.

-t

[InTheSand]

I'm surprised to see LHA beating ZIP and bzip2!

 - Ali

[Voyager74]

I'm surprised to see LHA beating ZIP and bzip2!
 
- Ali

I always knew LhA was faster, but I'm surprised to hear that Debian
should have taken ownership of it.
PDF's use LZW, I always used either lzx or lha for Amigapurposes.

[Failure]

Lha might be considered non-free because of the patents on the LZW algorithm.  Was it Unisys trying to exploit royalty rights to LZW before its patent ran out?  This was a few years ago.  I could Google it and find the answer, but then again so could you

Indeed!  I looked a bit more and came across this which basically states that the license is too vague.  After reading it more closely I agree.  Here's one part that makes me smile:

You need to put effort to distribute the latest version (This is not your duty).
   
NB: Distribution on Internet is free.  Please notify me by e-mail or other means prior to the distribution if distribution is done through non-Internet media (Magazine, CDROM etc.)  If not, make sure to Email me later.

In other news I tried these utilities on some larger files and obtained virtually identical results, although bzip2 leaped ahead as it normally does.  So zoo looks like an ok choice.