Barcodes have been widely used in daily life. It not only makes life easier, but also can be used to convey information precisely and quickly. Because of technology advancement of smart portable device, everyone is able to acquire information by a portable barcode decoder.
Based on international standard ISO/IEC 18004, the study implemented a QR code decoder with automatic correction of perspective distortion and translation/rotation/scaling invariance. In order to increase the barcode recognition rates, QR code has three position finders. This setting allows QR code to be decoded from any angles. In the study, a whole procedure of decoding process, from image acquiring, finder localization, symbol precise localization, perspective correction, module sampling, and Reed-Solomon decoder were implemented. This study is a good practice of application of machine vision and barcode decoding.
