Versions tested: 1.041
Optimal parameters: -
Authors: Malcolm Taylor
Algorithms: PPMZ, X86
Notable peformances: -


Here are compression related quotes from the program documentation:

-TNNNN The table size used by the fast and normal modes (max 16384). A larger table size will be slower, and will not always provide better compression.

-BNNNN The buffer size (in kb). This is the size of the buffer for both the fast, normal and max modes. A larger buffer will allow the algorithm to refer to more data when compressing, and consequently _may_ improve compression (it usually will not harm compression ratio).

-MNN The PPMZ model size for the max mode (in Mb). This only affects the normal and max modes, and a larger model generally will increase compression ratio (esp. for long files or large sets of similar files). NB. Model sizes greater than 8Mb will likely have no effect on the normal mode, as it uses much less memory than the max mode.

-mw[fnx] The WAV compression method. When RK comes accross a WAV file it will automatically use a specific WAV compression method instead of the main method. With this option you can specify the amount of work RK spends on compressing WAVs. -mwf Fast mode. -mwn Normal mode. -mwx Max mode.

-f[...] The filtering method to use. There are several filters that can be applied to the data as it is being compressed. Normally rk will select the appropriate automatically on a per file basis. By using this option it is possible to force certain filters to be used or not. The filters are as follows:

-fd{n} Delta filter where n is a number from 1 to 16. This filter performs the transform y[i]=x[i]-x[i-n].

-fe The x86 EXE filter. This does JMP/CALL translation which improves compression ratio on x86 executable code. RK can automatically recognize most Win32 and DOS exe types, but I do not recognize unix formats yet.

-ft Text filter. This performs a transformation on textual data that improves the compression ratio.

All filters can be forced on or off by using + or -. If a filter is forced off then RK will not use it even if it recognizes the file type.

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

Disqualified: when launched with 'rk.exe -r test.rk cc1.exe' causes 'test.rk' to be created into the root directory while the program scans something from the hard drive causing disk sleep.

Disqualified (why) configurations (with qualification ratings)
Ver Rating CPR DPR S.E. R.E. Ratio C. kB/s D. kB/s
1.041 - (q1, q2)

Version info

1.041, tar: no, mode: n/a, crc32: n/a, decoder: n/a, tested: 2009 Feb 22
compression: rk.exe -r <args> <cfile> <src>
decompression: rk.exe -x <cfile>