How does a smartphone, feature phone or camera phone read a QR code?
.A QR code contains a matrix of small light and dark squares having a solid light margin and other specific characteristics (See QR code specifications). The QR code must have a margin (also known as the QR code frame or QR code whitespace or QR code quiet zone) which allows the interpretive software on your phone to isolate a QR code in an image even if text or pictures or other unrelated objects surround the QR code in the image.
- QR code software – Camera Phone software integrates with your phone’s camera
- Snap the QR code image via the software
- The software first searches the image for a square or rectangle surrounded by a quiet zone that meets the specification.
- Using the three positioning squares and other markers printed in the code, the software read and interprets the small pixels (or dots) in the QR code.
- Having interpreted the dots of the QR code, the software reads a flag the data that establishes if the data in the code was text or a URL or (more data here)
- The QR code reader program then takes an action based on the type of data was read from QR code. Most commonly, a QR code can contain a URL (Internet address). After a QR program reads a QR code containing a URL (Internet Address) the QR code reader typically starts an Internet browser and automatically loads the Internet website that was encoded in the QR code. Note that not all QR codes contain URL web site addresses; QR codes can contain message text, address text, and other useful data that does not require an Internet connection. If a QR code contains address information, some QR programs will automatically display a contact management dialog to allow the information to be added to a contact management program. If a QR code contains a text message, most QR readers will display the text message with no Internet connection required.