Design Of PDF417 Code Recognition System Based On SOPC

With the development of information technology, barcode recognition technology has been applied to various fields such as logistics and transportation. The two-dimensional barcode, which has a large capacity and strong error-correcting ability, has become a research hotspot of barcode recognition technology. For the general 2D-barcode recognition system, it requires higher real-time performance and stronger practicability, so the barcode recognition algorithm should be less complex, faster computing-speed.On the basis of the image recognition technology, reed-solomon correction technology and embedded system technology, this paper proposed a wireless PDF417 code recognition system architecture based on SOPC, designed the hardware platform of whole barcode recognition system, deeply studied each link in the barcode recognition algorithm and realized the algorithm combined software with hareware. The thesis includes the following parts:a) According to the market requirement for two-dimensional barcode recognition system, this paper built up a wireless PDF417 code recognition system based on SOPC combined with the design features of NiosII embedded processor and FPGA, realized these functions such as image acquisition, recognition, display of data decoded in real-time and wireless data transmission.b) Through the research of the existing barcode image recognition algorithm, combined with the characteristics of PDF417 code image, a barcode image recognition program with fast response speed was proposed. For the requirement of high real-time of barcode recognition system, the part of time-consuming algorithm is accelerated by using FPGA hardware module. The speed of PDF417 code image recognition is greatly improved.c) Based on the principle of RS error-correcting codes, the paper researched the RS error-correcting algorithm in PDF417 code and implemented it in the embedded environment. An inquiry table was designed to improve the speed of error-correcting. Realized the decoding of PDF417 barcode by studying the standard of the PDF417 bar code.The result of experiment shows that the system architecture is effective and feasible, the speed of recognition for PDF417 code is less than 2 seconds, and the recognition rate reaches up to 93%, in terms of cost, power consumption and scalability has unique advantages and good development.