The Research Of Code/Decode And Automatic Identification Technology Of QRCode

As the global information developing, people request for improved barcode technology. It's required that presenting more information in limited area. As the requirement came out, two-dimensional (2D) symbol technology was proposed and in general use. Two-dimensional (2D) Barcode has played an important role in the information automation field because of its higher capacity, higher density, more powerful error-correction ability and higher security ability. The Recognition Tech- nology of 2D is to be asked more simple and easier because of its wider appli- cation, and even no dedicated decoding equipments, it can also be achieved with collecting 2D bar code images with camera. This paper aiming at implementing decoding of images collected by camera, proposed a coding and decoding system. The content as bellows:The paper introduced basis of knowledge and characteristics of two dimensi- onal barcode and QRCode in the first part and chose QRCode as object of study. QRCode had Chinese Character Set, so that it was more suitable for Chinese situa- tion compared with other 2D barcode. And the second part of paper was about re- search of coding system. Discussed the design of coding system focused on deter- mination of coding mode. Based on the reference algorithm of GB/T 18284-2000, made some improving, and achieved good results. The third part of paper was about research of decoding system. First introduced how to process the collected barcode images with image processing methods including median filtering, image binarization and so on. According to the actual situation, chose a suitable method. The focus of decoding system research was automatic identify- cation, including locating and grid building arithmetic of code symbol. The symbol locating arithmetic of QRCode was fully use of three Finder Patterns. Scanned three finder patterns and then picked up the real scan line through three finder patterns in order to calcu- late the center coordinates and finally finished symbol locating. Because of impact of rotating, deformatiom and features of symbol image itself, when scanned symbol image, there might be some scan lines which was not belong to the area of finder patters. So How to judge these scan lines and pick up the real lines accurately was also a focus of research. The forth part of paper was about the implement of the whole system. It introduced how to implement coding and decod- ing system. And introduce the submodule of each system and the relationship among them in detail. And finally, there were some main flow charts of system. And the last part was the effectiveness test.The result of research on Visual c++.net platform showed the system of coding and decoding is effective. The coding system can code accurately and decoding system also decode accurately.