RData Matrix

Introduction

The package RDataMatrix contains an applet and Java[TM] class that will allow you to create data matrix (ECC200) barcodes for you Java[TM] applications or HTML pages.

Data Matrix is a two-dimensional (2D) matrix symbology which is made up of square modules arranged within a perimeter finder pattern. It can encode up to 3116 characters from the entire 256 byte ASCII character set. The symbol consists of data regions which contain square modules set out in a regular array. Large ECC 200 symbols contain several regions. Each data region is delimited by a finder pattern, and this is surrounded on all four sides by a quiet zone border (margin).

ECC 200 symbols have an even number of rows and an even number of columns. Most of the symbols are square with sizes from 10 x 10 to 144 x 144. Some symbols however are rectangular with sizes from 8 x 18 to 16 x 48. All ECC 200 symbols can be recognized by the upper right corner module being light (binary 0).

ECC200 is the newest version of data matrix and supports advanced encoding error checking and correction algorithms (reed-solomon). This algorithms allow the recognition of barcodes that are up to 60% damaged.

The barcode supports two optional mechanisms:

The "Extended Channel Interpretation" (ECI) mechanism enables characters from other character sets (e.g. Arabic, Cyrillic ..) and other data interpretations or industry-specific requirements to be represented.
The "Structured append" allows files of data to be represented as a secuence of up to 16 Data Matrix symbols. The original data or file can be reconstructed regardless of the order of the symbols.

RDataMatrix supports:

All sizes and formats (from 10x10 till 144x144)
Ascii, text , C40 and Base256 (for binary data) encoding.
The "Extended Channel Interpretation and Structured append

Formats

RDataMatrix supports all data matrix formats. The following table contains the size , the capacity and the correction error features of each format:

Size	Numeric Capacity	Alphanumeric capacity	Binary capacity	Max Correctable Error/Erasure
10 x 10	6	3	1	2
12 x 12	10	6	3	3
14 x 14	16	10	6	5/7
16 x 16	24	16	10	6/9
18 x 18	36	25	16	7/11
20 x 20	44	31	20	9/15
22 x 22	60	43	28	10/17
24 x 24	72	52	34	12/21
26 x 26	88	64	42	14/25
32 x 32	124	91	60	18/33
36 x 36	172	127	84	21/39
40 x 40	228	169	112	24/45
44 x 44	288	214	142	28/53
48 x 48	348	259	172	34/65
52 x 52	408	304	202	42/78
64 x 64	560	418	278	56/106
72 x 72	736	550	366	72/132
80 x 80	912	682	454	96/180
88 x 88	1152	862	574	112/212
96 x 96	1392	1042	694	136/260
104 x 104	1632	1222	814	168/318
120 x 120	2100	1573	1048	204/390
132 x 132	2608	1954	1302	248/472
144 x 144	3116	2335	1556	310/590
8 x 18	10	6	3	3
8 x 32	20	13	8	5
12 x 26	32	22	14	7/11
12 x 36	44	31	20	9/15
16 x 36	64	46	30	12/21
16 x 48	98	72	47	14/25

Encoding

The data represented in the symbol is can be compressed using one or several of the following algorithms:

ASCII: it is used to encode data that mainly contains ascii characters (0-127). It encodes one alphanumeric or two numeric characters per byte.
C40: it is used to encode data that mainly contains numeric and upper case characters. C40 encodes three alphanumeric data characters into two bytes.
TEXT: it is used to encode data that mainly contains numeric and lowercase characters. TEXT encodes three alphanumeric data characters into two bytes.
BASE256: it is used to encode 8 bit values.

All encoding system can be used to encode any data, but for example, encoding binary data with C40 generates much more overhead (longer symbol) than with BASE256.

Control characters

RDataMatrix uses the character ~ to recognize some special characters in the input data. The following possibilities are available:

~X is used to represent character values from 0 to 26. Replace the X like in the following example ~@ = means character ascii 0, ~A= means character 1, ~B=means character 2, ~C=means character 3 ...
~1: represents the character FNC1. When FNC1 appears in the first position (or in the fifth position of the first symbol of a Structured Append), it will indicate that the data conforms to the UCC/EAN Application Identifier standard format.
~2: It is used to represent Structured Append. Structured Append is used to link information from several symbols in a secuence. The ~2 must be followed by 3 additional bytes. The first 4 bits of thie first byte identify the position of the particular symbol in the secuence . The last 4 bits identify the total number of symbols in the secuence. The second and third byte are used as a file identifier are can have a value between 1 and 254 (up to 254*254=64516 identifiers). See Data Matrix Specification for more information about this (ISO 16022).
~3: This character are only allowed in the first position of the symbol. It indicates that the data contains commands for the barcode reader.
~4: not allowed.
~5 and ~6: These characters are only allowed in the first position of the symbol. If ~5 is used the header [)> ascii30 ascii05 ascii29 will be transmitted by the barcode reader before the data in the symbol and the trailer ascii30 ascii04 will be transmitted after the data. If a ~6 is used , the header [)> ascii30 ascii05 ascii29 will be transmittedby the reader before the data and the trailer ascii30 ascii04 will be transmitted afterwards.
~7NNNNNN specifies the Extended Channel to be used, where NNNNNN is a value between and 000000 - 999999. For example: ~7000010 means Extended Channel 10 . Extended channel is used for using other character sets other than ascii. See Data Matrix Specification for more information about this (ISO 16022).
~dNNN represents the ascii character encoded by the 3 digits NNN. For exmaple, ~d065 represents the character 'A'.

References