The Flemish Innovation Center for Graphic Communication (VIGC) tested codes in adverts, magazines and brochures and found that the majority were only readable by handsets with a high quality camera component, with sophisticated focus and zooming functions

"There are lots of really nice things you can do with QR codes," says Eddy Hagen, general manager of VIGC. "As a minimum you can include a web link so people can find out more about a product, service or event. You can provide your contact details and even add the location of your office to within one meter.

"But all of this is a waste of time if the QR code isn't readable - and this is where many QR codes fail."

The VIGC QR Code Test Service uses a range of smartphones - both older and newer models - and different types of QR reader software, to produce a comprehensive report on the performance of a particular code, and includes suggestions for improving readability where necessary.