qr-code

QR code (abbreviated from Quick Response Code) is a type of matrix bar code consisting of black modules (square dots) arranged in a square grid on a white background.

The QR code can be used to encode text and binary data of variable length. It is possible to encode up to 2953 code words. The code value is converted from the XML unicode value to the specified encoding.

By default, the bytes encoded in a QR code image are interpreted as characters from the ISO-8859-1 (Latin 1) encoding. Other encodings can be specified in the encoding attribute and an extended channel interpretations (ECI) code will be inserted if available for the encoding. The code covers issues such as:
An ECI code exists for the following encodings:
Attributes unique to this bar code type:

QR code examples

This figure shows a QR code of Hello World with an unspecified size and an error correction degree setting of 3 (the default).

Figure 1. Hello World: size not specified (default error correction (3))

This figure shows a QR code of Hello World with an unspecified size and an error correction degree setting of 2.

Figure 2. Hello World: size not specified (error correction degree (2))

This figure shows a QR code of Hello World with an unspecified size and an error correction degree setting of 1.

Figure 3. Hello World: size not specified (error correction degree (1))

This figure shows a QR code of Hello World with a specified width of three centimeters.

Figure 4. Hello World: width="3cm"

This figure shows a QR code example of a web site address: http://www.4js.com.

Figure 5. http://www.4js.com