Information

All programs are tested in free downloadable version, that includes evaluate, freeware, shareware, demo, trial and all other licences. I really don't have money to buy programs for testing, so if author of this program would give me free licence I would be grateful and then I'll try to include latest version of this program as soon as possible. In other cases it can take a bit longer.

Compression test

In compression test 12 different file sets are used. Each set consists of files of specific types and each has the same size (1 000 000 bytes). Currently used sets are:

Set type (extension)	Number of files	Comments
Bitmaps (BMP)	28	All bitmaps are uncompressed
MS Word Documents (DOC)	16	MS Word 6.0 and later files
Executable files (EXE)	23	Windows and DOS programs with no internal compression
Images (GIF)	103	Mostly 256-color
HTML files(HTM)	43	Only manually created files (no export from Office etc.)
Images (JPG)	21
Music files (MID)	42
MP3 files (MP3)	2
Fonts (TTF)	14
Text files (TXT)	178	Tests ability of program to handle small archives
Audio files (WAV)	57
Excel workbooks (XLS)	5

Extensions are also used in tables to identify test set.

PackScore

PackScore is special score for comparing performance.

It is calculated by following equation: PackScore=20*log(s/((tc+2*td)/tr)) , where:

s	=	Size of compressed file
t_C	=	Time of compression
t_D	=	Time of decompression
t_R	=	Reference time

Reference time is used to reduce computer performance influence to results. Reference test is performed with PKZIP version 2.04g with 12 000 000 bytes of data (all test sets).

Time measurement

Command-line packers execution time was measured by Microsoft TimeThis utility from Windows 98 Resource Kit. For interface programs this measurement was done with normal stop watch.

Program details

For each compression program is here one special page that makes short summary about this program. Here are some explanation to these pages:
Default extension: first is always packer-native and then are with full and small support. Full support means that program can create, handle and extract these types by it's internal functions. Small support means that it can display archive content (and extract files using external program)
After install size: there are not included files added in windows directory, sorry but there would be problems which file is added in which system....
Advantages/Disadvantages: This is my personal rating to programs abilities.

Machine

All test are made on computer based on Intel Celeron 366 MHz processor and equipped with 92MB RAM. Used OS is now only Windows 98 CZ but Linux test may come soon. For tests is used 2 GB FAT 16 partition of 8.4GB Quantum Fireball disk.

If you don't understand something try to find answer in information.