Unidirectional Information Transmission System Based On Two-Dimensional Bar Code And Image Processing

According to the “People’s Republic of China on Guarding State Secrets Law”,“International Networking of Computer Information Systems confidentiality regulations”andthe Ministry of Public Security Technology Information Bureau “Unidirectional datatransmission of the public network and public security information communication networksecurity (Trial)”, involving dense computer with the Internet and other public informationnetworks must be physically isolated, not be classified computer the classified storage devicesto access the Internet and other public information network. Currently, non-classified networkthe external network to the classified network information transmission network only throughthe artificial way, real-time and reliability of lack of demand can not meet the real-timeupdates of the data in the classified department information construction.The subject, starting from the information construction point of view of the use of units,analysis of the party and government organs in China construction the existence of thephenomenon of the "islands of information" and the actual work needs; research and analysisof existing artificial transmission of data carrier principle, security flaws cost, use, anddetailed analysis of the principle and disadvantages of network isolation device. Analysis ofthe maturity of the technology and with international and domestic standards PDF417GridMatrix Code and QR code and anti-distortion and presentation of multimedia informationfrom the code words capacity, error correction information, compare the three-dimensionalbar code. Comparative analysis of the principles, techniques, safety levels, combined with thedevelopment of the two-dimensional bar codes and digital image processing technology, QRtwo-dimensional bar code technology and digital image processing proposed use of theintranet the external network non-classified and classified data unidirectional transmission.Analysis and design based on the two-dimensional bar code and image processing ofunidirectional information transmission system of three subsystems: data encoding displaysubsystem, Digital image capture subsystem, the image decoding subsystem should have thefunctionality and performance, and complete system hardware design structure. Three subsystems module design and the completion of the process design. Complete systemhardware selection, and the system QR code version selection is determined by the hardwareperformance parameters projections, as well as amendments to the QR Code symbol numberof characters and data capacity checksum.In order to enhance the image of the QR code arithmetic processing speed and thedecoding speed, starting from the image decoding subsystem design elaborated: Using medianfiltering, adaptive threshold binarization, swelling and corrosion of the algorithm forprocessing the QR method; using wavelet change, image positioning algorithm, the samplinggrid algorithm QR graph data partitioning. Elaborated optimization algorithm processing,improve the error correction decoding rate in the case of error in the code word of the RSerror correction algorithms.The complete system hardware and software structures, according to the characteristicsof the system used in a real-time unidirectional transmission, after a long period of time to testthe system hardware is running well and without fault occurred. Through transmission test avariety of file formats, to prove the system after the completion of the transfer of the data,does not affect the contents and characteristics of the data. And file transfer test by the rate ofthe system of the actual transmission of data and to analyze the impact of the transmission filetime reasons.Through continuous testing of unidirectional-way information transmission system of thetwo-dimensional bar code and image processing, the system has the reliability, availabilityand security, system transfer rate2KB/s, to meet the day-to-day needs of the office secretdepartment of real-time data updates, the system has a certain market application prospects.