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Up Topic The Rybka Lounge / Opening Books / Better compression for CTG books
- - By ritm (**) [ru] Date 2015-02-02 09:52
I wrote program to remove junk data from Chessbase openings books (.CTG format).

Yielding in better compression ratio, compression and decompression speed.

Use it for sharing compressed (ZIP, RAR, 7Z, Nanozip etc) books or for long-term archiving.

Download

Simple CLI interface: just pass .CTG file to program as parameter.
Parent - By ritm (**) [ru] Date 2015-02-02 10:00
Example of it work: PoisonedArrows3x.7z - 905MB. After cleaning and re-compressing - 744MB.
Parent - - By jeandis (***) [ve] Date 2015-02-02 11:16
how do you use it?
Parent - By ritm (**) [ru] Date 2015-02-02 11:25
Parent - - By Fulcrum2000 (****) [nl] Date 2015-02-02 17:19
Interesting. What kind of junk data inside the ctg-format are we talking about?
Parent - - By Banned for Life (Gold) Date 2015-02-02 17:34
Your favorite opening lines! :lol:
Parent - By Fulcrum2000 (****) [nl] Date 2015-02-02 21:17
:wink:
Parent - By ritm (**) [ru] Date 2015-02-02 17:51
ctg file consists of 4096-byte blocks, each with header and tens of positions.
those don't occupy all 4096 bytes and header telling used bytes in block. the rest is junk (old, moved or deleted positions)
if used 3072 bytes, 1024 bytes are junk and my program cleans it with zeros.
ref. http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=2319
Up Topic The Rybka Lounge / Opening Books / Better compression for CTG books

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