Design And Development Of Two-Dimension Barcode Recognition Of Smart Phones

With the development of information technologies, barcodes have been widely used in many fields. Due to the limit of the information capacity, one dimensional barcode is just a label for goods. They must be used with database. With the development of high technology, it is urgent for using barcode to express more information within the limited printing space, which could realize the description for goods. Two-dimensional barcodes appeared just about to meet upwards requirement.This thesis is about the identification system of two-dimension bar code. Decoding software running on mobile phones identifies the QR code at the open environment and gives the final results. Optimizing image process algorithm that can be used in smart phones is studied in this thesis. The main content of this paper is as follows:(l)To provide good versatility and scalability, the system is developed based on the standard DirectX, which is established by Microsoft Corp and is hardware-independent. DirectShow development kit is employed as the system development framework. With hardware based on Windows mobile platform, and software using modular design method, the transmission of video streaming and image processing is established used DirectShow technology.(2) Based on the special environment of smart phone and the characteristic of the code images, the thesis presents an adaptive algorithm for uneven illumination image and adopted mathematical morphology to filter binary image, which can greatly reduce the difficulty of the position recognition .(3)In the process of localization, a recognition algorithm of QR code using its symbol characteristic is put forward based on traditional algorithms. The improved algorithm alleviates the contradiction between the demand of resources and the limited power of the mobile phone. (4)As QR code has the position detection pattern, the recognition procedure is improvement on the basis of the procedure recommended in the GB/T18284-2000 National Standard to make it work more smoothly. According to the discussion on the code role of the barcodes, most part of the algorithm can also be used in other barcode image recognition procedure.This thesis completed the two-dimensional bar code identification system based on Windows mobile. Experiments show that the system 's recognition rate is up to 93.1%, which can meet the needs of the practical application.