Japanese postal barcode

The Japanese postal barcode is used in mail sorting for Japan. It encodes an 7-digit postal/zip code plus an optional alphanumeric address code. The symbology allows the coding of the digits 0-9, letters A-Z, and hyphen. The address code is simply the alphanumeric portion of a street address.

This sort of bar code system is regarded as "four-state" because there are four types of bars, classified by presence of ascenders and/or descenders. This sort of system is transcribable using DAFT notation. These sorts of bar codes are used by a number of countries in their postal systems, though the specific symbologies by which they encode characters can vary.

The scheme
The start and end bars are FD and DF. Each character takes up three bars. Padding with TDA is performed to fill 20 chars.

Utilities

 * Barcode generator: Japanese postal bar code
 * TEC-IT Reference (Covers general information and address storage)
 * Barcode generator, in PHP

Links

 * Barcode structure, seagull scientific (covers alphanumeric, but does not have exact values for each three-unit)
 * Japan Post bar code info
 * Discussion of the encoding of these bar codes
 * Japanese postal/zip code directory