| Readme: | Note: A XPK library needed for some demos.
RAKE
A cruncher of the LZ77 family
for the XPK-package
Version 1.7
Copyright 1995 by Karsten Dagef�rde
Status: FREEWARE
License/Disclaimer
------------------
This library may be freely distributed, as long as it is kept in its
original, complete, and unmodified form. It may NOT be distributed in a
commercial package of any kind without my permission.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE.
Installation
------------
You'll need to install the XPK package first to use this library. The
XPK package should be available on most Bulletin Board Systems, so try to
get it there.
If you already have the XPK package installed, add this library to
your system simply by copying the xpkRAKE.library to your LIBS:Compressors/
directory. The library can be found in xpkRAKE_68000/ or if you have a 68020
(or greater) processor, take the library placed in xpkRAKE_68020/.
Description
-----------
RAKE is an XPK packer sublibrary which implements a highly optimized
form of the popular LZ77 compression algorithm. It uses static huffman
coding for the 'len' and a three-step coding for the 'offset'
information. The major feature of this packer is the highly optimized
algorithm for tracking down redundant data.
RAKE supports four modes at compression (see below).
- Scanner & Coder together fit in 68020 instruction cache
- Hashbuffer-size will be reduced downto 0.5Kb, if memory is short
-----------------------------------------------------------------------------
NOTE: There is no need to repack files packed with RAKE V1.0 - V1.6
(68000 or 68020 version), because RAKE V1.7 is totally compatible
with older versions and vice versa, it just works faster.
-----------------------------------------------------------------------------
Statistics
----------
Following is a table briefly listing some statistics for RAKE. They
were generated by xBench on an A3000/25 with 2+8 MB Mem, using the
AmigaVision executable as data (standard xpk benchmark configuration).
Note that memory needs don't include xpkmaster.library's buffers.
68020 version: Mem usage [Kb]
Packer UComp Comp CF CTime CSpd UTime USpd Pack/Unpacking
----------------------------------------------------------------------------------
rake.100 594712 322872 45.8% 6.64 89565 0.90 660791 256 0
rake.075 594712 324964 45.4% 5.73 103789 0.91 653529 256 0
rake.050 594712 326908 45.1% 5.13 115928 0.91 653529 256 0
rake.025 594712 328796 44.8% 4.77 124677 0.92 646426 256 0
68000 version: Mem usage [Kb]
Packer UComp Comp CF CTime CSpd UTime USpd Pack/Unpacking
----------------------------------------------------------------------------------
rake.100 594712 322872 45.8% 7.07 84117 1.16 512682 256 0
rake.075 594712 324964 45.4% 6.16 96544 1.17 508300 256 0
rake.050 594712 326908 45.1% 5.56 106962 1.17 508300 256 0
rake.025 594712 328796 44.8% 5.20 114367 1.18 503993 256 0
History
---------
Sep-9-94 V1.0 First public release (68000,68020)
[...]
Jul-1-95 V1.6 - Scanning algorithm improved.
Sep-6-95 V1.7 - 68020 version now checks if there is an appropriate
processor (68020 or better)
Contact Addresses
-----------------
dagefoer@ibr.cs.tu-bs.de (preferred)
OR
dagefoer@rob.cs.tu-bs.de
OR
K.Dagefoerde@tu-bs.de
\\//_ Live long and prosper
|
Ambient (143)
xpkRAKE.library_1.7.lha