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-
- SIG m.b.H
- tom ehlert
- bachstrasse 22
- D-5100 aachen
- germany
-
-
-
- This is my entry to the DDJ Compression Contest
-
-
- Right now I have a problem: I just reread the conditions
- under which I may participate at the contest and (re)learned that
- I MUST fill an ENTRY FORM which I don't have. Scince I have
- no access to Compuserve I FAXed to DDJ for the request for
- this entry form, but it's not yet here (5 hours later). So I
- try to imagine what might be asked on this entry form and
- hope for the best.
-
-
- program name : HSTEST
- program author : tom ehlert
- post address : SIG m.b.H
- tom ehlert
- bachstrasse 22
- D-5100 aachen / germany
-
- phone number : 0241-502066
- FAX number : 0241-502068
-
-
- operating system : MS/PCDOS > 2.00
- memory requirements : >= 370 KByte
-
- compiler : MSC 6.00A
- assembler : MASM 5.1
- linker : MSLINK 3.65
-
-
-
-
-
- usage :
- HSTEST file compressed_file
- for fast compression/decompression
-
- HSTEST file compressed_file -F
-
- for better,slower compression/decompression
-
- HSTEST compressed_file file
-
- to decompress the compressed file
-
-
- sourcecode is on SRC\; regenerate with
- cd SRC
- tm ar
-
-
- right to the sourcecode by anybody else :
- none except the file PQ.C which is directly derived from
- a DDJ artikel in 6'87 (Priority Queues).
-
-
-
-
-
- Here a longer, more verbose description:
-
-
- programmname : HSTEST.EXE
-
- usage :
- HSTEST infile outfile [-options]
- options are
- -Uncompress infile to outfile,
- default is compress infile to outfile
- -Full (and slow) compression, default is fast mode
- -S print statistics
- -Quiet mode
-
-
- allthought the differenz in speed for fast or full compression
- is not very big, the speed during decompression is enormous.
-
- so if you want maximum compression use parameter -F, if you
- want fast decompression don't use it.
-
-
- What HSTEST is good for:
- HSTEST is an extremely basic File compression/decompression
- programm and not an archiving utility (like PKZIP etc.).
- I produced it just to demonstrate the combination of
- the combined pack() and hs_pack() routines and to keep
- the sourcecode as small (and understandable) as possible.
-
- A general archiving utility is also available, based on
- the above routines.
-
-
- REGENERATION of HSTEST:
-
- sourcecode is in SRC. regenerate with
-
- cd SRC
- tm ar
-
- AR.MAK is the makefile, it should document the process.
- HSTEST has been compiled with MSC600A and MASM5.1,
- but it should compile with any other C-Compiler as well
- provided that _fastcall,far,... keywords are supported
- or ignored.
-
- some (trivial) supportcode has been included to STOMLIB.LIB
- to make the differenz between packing and systeminterface
- more clear. its source is in LIB. STOMLIB.LIB can be
- regenerated using
-
- cd LIB
- tm tomlib
-
-
-
- Some comments about the proposed benchmarks:
- You want to measure the performance for compression ratio
- of files in the order of 2 MByte. Allthought this is certainly
- important, it is virtually useless for some cases which are
- often needed:
-
- sourcefiles (1..20 Kbytes usually)
- OBJfiles (1..20 Kbytes usually)
- Help-screens (1..5 Kbytes usually)
- compressed pictures :
- GEM .IMG (15..30 KBytes)
-
- these files are necessarily small. pack()/hs_pack() are
- inherently usable for small files, they compress even
- files of 1 Kbyte significantly. This is important for
- any archiving utility, because it's rather impractical
- to decompress 1 MByte of compressed file just to retrieve
- the last file of 100+ sourcefiles.
-
- So I would suggest you measure the performance for
- "normal" Files as well.
- I usually do this (to verify and measure HSTEST) by
- compressing/decompressing each File on my harddisk C:Drive
- (2500 Files, 32 MByte) or my server Harddisk
- (15000 Files,256 MByte).
-
- Beside this: I wish you some fun during the evaluation of
- probably several Gigabytes of compression / decompression
- Software.
-
- Last note:
- DDJ is one of the journals which I read since 6 years
- and will be reading 6 years to come.
-
- have fun
- tom ehlert.
-
-
-
-
- SIG m.b.H.
- tom ehlert phone 241-502066
- FAX 241-502068
-
- bachstr. 22
- D-5100 aachen
- germany
-
-