CJKV Information Processing, 2nd Edition

Legacy Encoding Methods

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Shi-JIS encoding does not support the characters dened in JIS X 0212-1990. ere is

simply not enough encoding space le in Shi-JIS to accommodate these characters, and

there is currently no plan to extend Shi-JIS in a manner such that JIS X 0212-1990 can be

accommodated. See Figure 4-16 for an illustration of the Shi-JIS encoding space.

Some denitions (in particular, corporate denitions) of Shi-JIS encoding also contain

encoding blocks for user-dened characters, or even a code point for the half-width ka-

takana “space” character. Such encoding blocks and code points are not useful if true

information interchange is desired, because they are encoded in such a way that they do

not convert to code points in other Japanese encoding methods, such as ISO-2022-JP and

EUC-JP encodings. Table 4-72 lists these nonstandard Shi-JIS encoding blocks and code

points.

Shi-JIS user-dened character encoding specicationsTable 4-72.

Encoding Decimal Hexadecimal

Half-width katakana

Half-width “space” character 16 

User-dened characters

First byte range

a

24–252 –

Second byte ranges 64–126, 128–252 4–7, 8–

Some implementations of Shift-JIS encoding implement a smaller user-dened character range, such as rows a.  through 9 or 

through .

Note how the second-byte range is unchanged from the standard denition of Shi-JIS—

only the rst-b ...