Ideographic Description Characters is a
Unicode block
A Unicode block is one of several contiguous ranges of numeric character codes (code points) of the Unicode character set that are defined by the Unicode Consortium for administrative and documentation purposes. Typically, proposals such as the ad ...
containing graphic characters used for describing
CJK ideographs
The Chinese, Japanese and Korean (CJK) scripts share a common background, collectively known as CJK characters. In the process called Han unification, the common (shared) characters were identified and named CJK Unified Ideographs. As of Unicode ...
. They are used in
Ideographic Description Sequences
The Chinese character description languages are several proposed languages to most accurately and completely describe Chinese (or CJK) characters and information such as their list of components, list of strokes (basic and complex), their order, a ...
(IDS) to provide a description of an ideograph, in terms of what other ideographs make it up and how they are laid out relative to one another.
[IDS are described i]
chapter 18.2 of the Unicode Standard 9.0
on pages 689 through 692. An IDS provides the reader with a description of an ideograph that cannot be represented properly, usually because it is not encoded in Unicode; rendering systems are not intended to automatically compose the pieces into a complete ideograph, and the descriptions are not standardized.
Block
History
The following Unicode-related documents record the purpose and process of defining specific characters in the Ideographic Description Characters block:
Ideographic Description Sequences
This is the syntax of IDS in
EBNF:
IDS := Ideographic , Radical , CJK_Stroke , Private Use , U+FF1F , IDS_BinaryOperator IDS IDS , IDS_TrinaryOperator IDS IDS IDS
CJK_Stroke := U+31C0 , U+31C1 , ... , U+31E3
IDS_BinaryOperator := U+2FF0 , U+2FF1 , U+2FF4 , U+2FF5 , U+2FF6 , U+2FF7 , U+2FF8 , U+2FF9 , U+2FFA , U+2FFB
IDS_TrinaryOperator:= U+2FF2 , U+2FF3
See also
*
Chinese character description languages
The Chinese character description languages are several proposed languages to most accurately and completely describe Chinese (or CJK) characters and information such as their list of components, list of strokes (basic and complex), their order, a ...
*
Specials (Unicode block)
Specials is a short Unicode block of characters allocated at the very end of the Basic Multilingual Plane, at U+FFF0–FFFF. Of these 16 code points, five have been assigned since Unicode 3.0:
*, marks start of annotated text
*, marks start ...
References
{{CJK ideographs in Unicode
Unicode blocks