Versions tested: 0.999b
Optimal parameters: a2
Authors: Harri Hirvola
Algorithms: PPM,LZ+HUF
Notable peformances: -


HA is a small file archiver utility. It's main goal is to offer maximum compression without fancy addons.


Available switches are:

the program documentation (info.txt)


HA is an archiver which I released in january 1993 as version 0.98. After that I had plans to improve speed, archive handling etc. which would have required total rewrite of the code. For that I unfortunately could not find time. Because there has been quite considerably interest for internals of HA (especially for the HSC compression method) I decided to make a source level release from my current test version (0.999 beta) and place it under GNU General Public License. The sources for this version are not very consistent or clean, but everything should work.

There are several improvements which should be made before this could be called version 1.0. Some of the most obvious of these are:

This archive ( contains this readme, MSDOS executable ha.exe and source files for HA 0.999beta. Ha.exe is NOT compiled directly from included sources. Some critical parts of it were compiled from hand optimized versions of compiler output. It is somewhat faster than "pure C" version.

MSDOS sources are for Borland C 4.0 but older versions of bcc should work. Makefile needs some editing as some paths are hardcoded in it. UNIX sources are not very generic. I have only tested this using Linux on PC and AIX on IBM6000. Only compiler and make utility that I have tested are GCC and GNU MAKE.

Porting HA should be fairly easy as all machine specific code is in machine.h and machine.c under machine specific directories. Md_funcs.txt documents these functions. Examples can be found from pc and nix directories.

the program documentation (readme)


(Have info that should be added here? E-mail.)

Disqualified (why) configurations (with qualification ratings)
Ver Rating CPR DPR S.E. R.E. Ratio C. kB/s D. kB/s
0.999b crash while decompressing (app1)
0.999b 79 80 78 128 2 2.768 1624 1408

Version info

0.999b, tar: no, mode: 32-bit, crc32: c24d8ac4, decoder: 34 kB, tested: 2010 Apr 22
compression: ha.exe <args> <cfile> <src>
decompression: ha.exe x <cfile>