Interleaved 2 of 5
Encyclopedia
Barcode
A barcode is an optical machine-readable representation of data, which shows data about the object to which it attaches. Originally barcodes represented data by varying the widths and spacings of parallel lines, and may be referred to as linear or 1 dimensional . Later they evolved into rectangles,...
symbology encoding digit
Numerical digit
A digit is a symbol used in combinations to represent numbers in positional numeral systems. The name "digit" comes from the fact that the 10 digits of the hands correspond to the 10 symbols of the common base 10 number system, i.e...
s. It is used commercially on 135 film
135 film
The term 135 was introduced by Kodak in 1934 as a designation for cartridge film wide, specifically for still photography. It quickly grew in popularity, surpassing 120 film by the late 1960s to become the most popular photographic film format...
and on cartons of some products, while the products inside are labeled with UPC
Universal Product Code
The Universal Product Code is a barcode symbology , that is widely used in North America, and in countries including the UK, Australia, and New Zealand for tracking trade items in stores. Its most common form, the UPC-A, consists of 12 numerical digits, which are uniquely assigned to each trade item...
or EAN
European Article Number
An EAN-13 barcode is a 13 digit barcoding standard which is a superset of the original 12-digit Universal Product Code system developed in the United States...
.
I2/5 encodes pairs of digits; the first digit is encoded in the five bars (or black lines), while the second digit is encoded in the five spaces (or white lines) interleaved with them. Two out of every five bars or spaces are wide (hence 2 of 5). The digits are encoded as follows:
| Digit | |Line width | ||||
|---|---|---|---|---|---|
| 0 | n | n | W | W | n |
| 1 | W | n | n | n | W |
| 2 | n | W | n | n | W |
| 3 | W | W | n | n | n |
| 4 | n | n | W | n | W |
| 5 | W | n | W | n | n |
| 6 | n | W | W | n | n |
| 7 | n | n | n | W | W |
| 8 | W | n | n | W | n |
| 9 | n | W | n | W | n |
| 1 | 2 | 4 | 7 | 0 |
Where "n" is a narrow line (bar or space) and "W" a wide line (2.0 to 3.0 times the width of a narrow line). The wide lines form a two-out-of-five code
Two-out-of-five code
In telecommunication, a two-out-of-five code is an m of n code that provides exactly ten possible combinations, and thus is popular for representing decimal digits using five bits...
with consecutive values of 1, 2, 4, 7, and 0, where the code 0 has a value of 11. This is similar to the POSTNET
POSTNET
POSTNET is a barcode symbology that was used by the United States Postal Service to assist in directing mail. The ZIP Code or ZIP+4 code is encoded in half- and full-height bars...
bar code.
Before the actual pairs there is a start code consisting of nnnn (narrow bar-narrow space- narrow bar-narrow space), and after all symbols there is the stop code consisting of Wnn (Wide bar-narrow space-narrow bar).
Only an even number of digits can be encoded. Typically an odd number of digits is encoded by adding a "0" as first digit, but sometimes an odd number of digits is encoded by using five narrow spaces in the last digit.
A checksum can be added as last digit, which is calculated in the same way as UPC checksums.
There are very specific constraints on the height and width of the bars and the width of the "quiet areas", the blank areas before the start and after the stop symbol. See http://www.barcode-1.net/pub/russadam/i25code.html and http://www.spatula.net/proc/barcode/i25.src for more information.
On 135 film (35 mm) canisters it is used to identify the manufacturer, the film type, number of exposures and proprietary information in 6 digits. The barcode is located between the electrically read silver and black DX Camera Auto-Sensing Code and the film can exit lip. It is optically scanned by many film-processing machines when the cartridge is inserted for developing. (See Kodak patent 5761558.)
Identcode and Leitcode are variants of interleaved 2 of 5 with check digits used by Deutsche Post
Deutsche Post
Deutsche Post AG, operating under the trade name Deutsche Post DHL, is the world's largest logistics group. With its headquarters in Bonn, the corporation has 467,088 employees in more than 220 countries and territories worldwide and generated revenue of € 51.48 billion in 2010...
.
Links
- Online Interleaved 2 of 5 barcode generator.
- Online free barcode generator (Interleaved 2 of 5 included)