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CJK Decomposition Data

The CJK Decomposition Data File is a graphical analysis of the approx 75,000 Chinese/Japanese characters in Unicode. The latest version is 0.4.0, updated on 15 August 2012.

The download file is a utf8 text file. The data file is totally my own work, and distributed under 6 licenses, of which you only need choose one:
The data comprises the 36 strokes (0x31c0..0x31e3), the 115 radicals (0x2e80..0x2ef3, except 0x2e9a), the 20924 unified characters (0x4e00..0x9fbb), the 12 unique characters from the compatibility range (0xf900..0xfad9), the 6582 extension A characters (0x3400..0x4db5), the 42711 extension B characters (0x20000..0x2a6d6), the 4149 extension C characters (0x2a700..0x2b734), and the 222 extension D characters (0x2b740..0x2b81d).

Each record has 3 fields, viz, the character being defined, the type of decomposition, and a list of zero or more constituent components, like so:
The character being defined and the constituent components are either a Unihan token, in the basic or a supplemental plane, or a 5-digit number representing an intermediate decomposition not in Unicode. There are approx 10,000 such intermediate decompositions.

If you need a font, you can use the Hanazono font.

Only pictorial configurations are used, not semantic ones. Where characters have typeface differences I've used the one provided by the Mainland Chinese contribution to Unicode. When there's more than one possible configuration, I've selected one only.

The possible configurations and their meanings are:
Code regex Meaning Number of possible constituents
c component 0
m.* modified in some way, e.g. me=equivalent, msp=special, mo=outline, ml=left radical version 1
w.* second constituent contained within first in some way, e.g. w=within at the center, wbl=within at bottom left 2
ba|d second between first moving across or downwards 2
lock components locked together 2
s.* first component surrounds second, e.g. s=surrounds fully, str=surrounds around the top-right 2
a flows across >= 2
d flows downwards >= 2
r.* repeats and/or reflects in some way, e.g. refh=reflect horizontally, rot=rotate 180 degrees, rrefr= repeat with a reflection rightwards, ra=repeat across, r3d=repeat 3 times downwards, r3tr=repeat in a triangle, rst=repeat surrounding around the top 1

The s, a, d, and r codes may be followed by /t, /m, /s, or /o, to show whether the join touches, molds, snaps together, or overlaps, respectively.

Some more work needs to be done, including reducing the quantity of intermediate components by removing duplicates, lowering the number of components in many sequences, reanalysis of decomposition configurations, and of course quality checking and corrections.

Last edited Dec 6, 2013 at 12:09 PM by gavingrover, version 3


madmansnest Jan 21 at 4:14 AM 
Hello, Gavin!

Thank you very much for this effort.

Maybe you’ll be interested in adding the following decompositions too:


djense Aug 21, 2012 at 8:17 AM 
Hello Gavin,

First I have to say I am very impressed with all this data, I have a hard time understanding how you put that together and how many hours you must have spent on this.

I have a few questions.
- This latest version seem to have at least one new code (built), is that any different from "lock" ? Is there any other notable changes from the previous version ?
- It seems that you have replace a lot of the characters defined as "bd" or "ba" with something else, especially just "w"... I thought the previous way has somewhat more information on how the character was constructed.... (?)
- It seems to me the definitions of "s" and "w" are actually very similar to each other... ?

I am not really an expert in any of this so all this is more for my curiosity than anything else.

If you are interested, I am trying to use this to find characters that are (very) similar looking to each other. I'm having only very mild success so far... but have still quite a few things to try.