Sometimes, we try to capture a QR code with a good digital camera on a smartphone, but the reading eventually fails. This usually happens when the QR code itself is of poor image quality, or if it has been printed on surfaces that are not flat - deformed or with irregularities of unknown pattern - such as the wrapping of a courier package or a tray of prepared food. Now, a team from the University of Barcelona and the Universitat Oberta de Catalunya has designed a methodology that facilitates the recognition of QR codes in these physical environments where reading is more complicated.
The new system does not depend absolutely on the underlying topography, and is applicable to QR codes that can be found on tubular surfaces (bottles), food trays, etc. It is the first technological proposal capable of combining a generalist methodology and two-dimensional barcodes to facilitate the recognition of digital information.
The study, published in the journal Pattern Recognition Letters, is first authored by Professor Ismael Benito, from the UB's Faculty of Physics and Department of Electronic and Biomedical Engineering, and the UOC's Department of Computer Science, Multimedia and Telecommunications Studies. Cristian Fàbrega and Joan Daniel Prades, professors at the Faculty of Physics and the UB's Institute of Nanoscience and Nanotechnology (IN2UB), are co-authors of the research, as are experts Hanna Lizarzaburu-Aguilar and David Martínez Carpena, from the UB's Faculty of Mathematics and Computer Science. All the authors have participated in different positions in the creation of ColorSensing, SL, a UB spin-off company in the field of smart labelling.
Why are some QR codes difficult to read?
QR codes are a variation of the typical barcode, capable of collecting information in computer language - in a two-dimensional matrix of black and white pixels - when scanned with a scanning device. They facilitate access to data of interest, save time and resources such as paper, and have revolutionized the way users access information in the digital realm.
However, it is sometimes difficult to scan a barcode correctly. According to Benito, from the UB's Department of Electronic and Biomedical Engineering and former technology director of ColorSensing, this happens, "first of all, because of the quality of the image. Although many people today have access to good digital cameras, they cannot always capture the QR image well. Secondly, the print quality of the QR code and the colours used - with good contrast - is sometimes not satisfactory".
