QR code

QR code (Quick Response Code) is a trademark for the type of matrix barcodes (or two-dimensional barcodes) originally developed for the automotive industry in Japan. A barcode is an optical tag read by a machine, containing information about the object to which it is attached. The QR code uses four standardised coding modes (numeric, alphanumeric, binary and kanji) for efficient data storage.

The QR code system has become popular outside the automotive industry thanks to its rapid readability and greater capacity as compared to UPC barcodes. Extensions include product tracking, item identification, time tracking, document management and general marketing.

The QR code consists of black squares arranged in a square grid on a white background that can be read using image processing devices such as cameras and processed using Reed Solomon codes until the image is properly recognised. The necessary data is then extracted from the templates that are present in the horizontal and vertical components of the image.

The main advantage of QR code is easy recognition by scanning equipment, which makes it possible to use in trade, manufacturing and logistics.

The maximum number of characters that fit into one QR-code:

7089 decimal number system digits;
4296 decimal system digits and letters (latin);
2953 bytes (therefore, about 2953 Cyrillic letters in Windows-1251 coding or about 1450 Cyrillic letters in utf-8);
1817 hieroglyphs.

Application

QR codes are most common in Japan. Leading Japanese mobile operators jointly produce branded mobile phones with built-in support for QR code recognition.

At present, QR codes are also widely distributed in Asian countries and their use is gradually spreading throughout Europe and North America. They have received greatest recognition among mobile users – by installing a recogniser program, you can instantly enter text information into your phone, add contacts to your address book, navigate through web links, send SMS messages and so on.