EBZip

Revision as of 02:18, 11 August 2025

Electronic Book Zip or EBZ is a compression format used in electronic dictionaries that were distributed primarily on compact discs (CD). The electronic dictionaries stored on computers eliminates the need to have physical media, and allows remote referencing if it was connected to a network, using the likes of dserver or ebnetd for instance. It is likely that compression was needed due to the fact that hard disks were expensive compared to compact discs, when having a number of electronic dictionaries stored on a computer, it made little sense to retain physical media just to reference a number of words every so often, and to juggle around ejecting/inserting discs into the computer. For the expense of sacrificing few CPU cycles and potentially insignificant amount of memory, these electronic dictionaries could be made to take less storage space^[2], and allows faster dictionary lookups due to hard disks allowing random access.

The compression is lossless, initially using a modified zlib^[3], then likely unmodified zlib by the original ebzip author^[4]. Under a new maintainer, libdeflate was added on 2019-06-30.^[5] in addition to having JIS X 4081 UTF-8 extension support. Do keep in mind that not everything is compressed, EBZ format is not a container like ZIP for instance, selected files (typically CATALOGS and HONMON) are compressed and have their filenames bearing these extensions, e.g. HONMON.ebz.

Originally intended for electronic dictionaries that were distributed primarily on CD, it is possible to create your own dictionaries using other referencing materials, such as Wikipedia. Modern software transparently handles decompression, eliminating the need to manually decompress.

History

EPWING or Electronic Publishing-WING was a consortium of five members; Iwanami Shoten, Dai Nippon Printing, Toppan Printing, Fujitsu and Sony, produced the Electronic Book (EB) extension based on WING standard in circa 1991, with the aim to promote electronic publications in a common format, and to standardize WING onto ISO 9660 (the logical format for CD-ROMs), establishing the first edition (V1) of the EPWING convention.^[6]

EB-like software for Unix-like began circulating on Japanese Usenet as early as September 1991 in the form of Shar by Nishioka of Osaka University.^[7][8] Gradually over time, Motoyuki Kasahara, a member of Software Research Associates (SRA) and the author of EB Library, began developing ndtpd which handles electronic dictionary or dictionaries over the network. The first release of such software was around 1997-06-04 as ndtpd-1.0beta0 with which it included eb which was a library. Until the release of ndtpd-3.0alpha0 (2000-06-04), eb has always been included. EB Library began as a separate project with the first release in 1999-06-16 as eb-2.2. Both of these projects continued until the discontinuation of ndtpd (as a release) on 2003-05-24 with the version 3.1.5. eb remained to be maintained until 2010-03-08 with the version 4.4.3.

It is notable that Kazuhiro Ito (author of EBU - EB Library with JIS X 4081 UTF-8 extension) made a contribution to Motoyuki Kasahara's EB Library on 2000-06-24.^[9].

Identification

A EBZ file begins with bytes 45 42 5a 69 70 13.

Examples

These must be executed in the top level of (book) directory that contains CATALOGS file, otherwise it will default to your current directory $(pwd). See Wikipedia:ja:EPWING#ファイル構造 for the directory structure of book layout.

Show information about the file:

 ebzip --information

Decompress files:

 ebzip --uncompress wikipedia-fpu

Compress files:

 ebzip wikipedia-fpu

Test files:

 ebzip --test wikipedia-fpu

Show help:

 ebzip --help

Sample file

Software (mostly Japanese only)

See also: Wikipedia:ja:EPWING#検索ソフトウェア

• Windows
  • WinEBZip.exe on SRA's FTP server - no longer maintained
  • WinEBZip.zip on SRA's FTP server - no longer maintained
  • EBWin4
• Linux
  • EB Library directory on SRA's FTP server - no longer maintained
  • EBU - EB Library with JIS X 4081 UTF-8 extension
  • qolibri EPWING dictionary viewer

Links (mostly Japanese only)

• Wikipedia:ja:電子ブック (規格)
• Internet Archive's mirror of EB Library that was hosted on SRA's website
• EBU

References

1. ↑ ChangeLog - SRA website mirrored on Internet Archive
2. ↑ Kenkyusha dictionary CD and EPWING - sci.lang.japan NARKIVE - Internet Archive copy
3. ↑ Last version released with internal zlib - README.altered - version 4.1.3 - Misty De Méo
4. ↑ Internal zlib removed - Commit 742ddab (4.2) - Misty De Méo
5. ↑ EB Library with UTF-8 extension (in Japanese)
6. ↑ Wikipedia:ja:EPWING#成立の経緯
7. ↑ dserver/Electronic Book Dictionary server & clients (1/2) - AncientFJ - katsu.watanabe.name
8. ↑ dserver/Electronic Book Dictionary server & clients (2/2) - AncientFJ - katsu.watanabe.name
9. ↑ ChangeLog.1 (line 1371) - EB Library - Misty De Méo