Code page 953
| Company type | Japanese Industrial Standard |
|---|---|
| Industry | Character encoding, Computing |
| Founded | October 1, 1990 |
| Headquarters | Japan |
| Products | Auxiliary coded character set for Japanese language |
JIS X 0212 represents a Japanese Industrial Standard that defines an auxiliary coded character set for the Japanese language, designed to supplement and expand upon JIS X 0208 (known as Code page 952). Within IBM's code page system, it is identified as 953 or 5049.
This standard has contributed as a foundational reference for the development of Unicode's CJK Unified Ideographs.
History
The Japanese Standards Association (JSA) introduced this standard in 1990 with the objective of broadening the character repertoire beyond what was available in the primary JIS X 0208 set, addressing its limitations in character coverage.
Features
JIS X 0212 encompasses a total of 6,067 characters, which include:
- 21 Greek letters featuring diacritical marks
- 26 Eastern European letters with diacritics, predominantly Cyrillic
- 198 alphabetic characters adorned with diacritics
- 5,801 distinct kanji
Encodings
When encoding JIS X 0212 characters digitally:
- In EUC-JP, characters are represented using a three-byte sequence: a leading byte followed by two bytes within the – range.
- Certain ISO 2022-based JIS encoding schemes—such as ISO-2022-JP-EXT, ISO-2022-JP-1, and ISO-2022-JP-2—utilize the escape sequence
ESC $ ( Dto indicate JIS X 0212 characters.
Due to limited code space, there is no mechanism for representing JIS X 0212 within the widely adopted Shift JIS encoding format.
Implementations
IBM refers to JIS X 0212 as Code page 953, which includes proprietary extensions; conversely, the related CCSID 5049 excludes these vendor-specific additions.
Because JIS X 0212 cannot be encoded in Shift JIS—the predominant Japanese encoding—its practical use remains restricted. Its primary encoding environment is EUC-JP, extensively utilized on Unix and Linux platforms, where most implementations have emerged:
- During the early 1990s, fundamental "BDF" fonts were assembled for the Unix X Window System;
- A conversion file for input method editors (IME) was developed for the Wnn system;
- The kterm terminal emulator was enhanced to support these characters;
- Text editors such as Emacs and jstevie incorporated functionality for handling them.
Major web browsers including the Netscape/Mozilla/Firefox series, as well as Opera, along with applications like Mozilla Thunderbird, provide support for rendering JIS X 0212 characters when using EUC-JP. In contrast, Internet Explorer does not offer such support. Contemporary terminal emulators like GNOME Terminal also accommodate these characters.
Key software supporting JIS X 0212 in its EUC form includes:
- the xjdic dictionary application tailored for Unix/Linux environments;
- the WWWJDIC online Japanese dictionary service, which delivers bitmapped images for unsupported characters when accessed with Internet Explorer under EUC-JP settings.
JIS X 0212 and Unicode
The kanji set defined in JIS X 0212 played a significant role in the process of Han unification, influencing the creation of the unified collection of CJK characters found in the original ISO 10646/Unicode standards. All of its 5,801 kanji were fully integrated.
The future
Although largely superseded today, JIS X 0212’s legacy persists through the inclusion of 2,743 kanji in the subsequent JIS X 0213 standard. Its most enduring contribution lies in having its entire kanji repertoire absorbed into the Unicode system.
See also
References
- JIS X 0212-1990 情報交換用漢字符号―補助漢字, 日本規格協会, 東京 (制定日: 1990年10月1日).(Japanese standards document)
- Ken Lunde, Understanding Japanese Information Processing, O'Reilly & Associates, 1993
- Ken Lunde, CJKV Information Processing, O'Reilly & Associates, editions from 1999 and 2008