Applied Research Related To Computing In The Bar Code Positioning

The correlation operation in mathematics has been widely applied in physics,computer science and information science. The digital correlation method which iscommonly used in the precise image measurement, the high-precision localization ofimage goals develops just basing on the principle of the correlation. And it is very simple,strong adaptable (low requirements to environment, strong ability of anti-jamming),precise, ect. So has wide application in many fields.The digital correlation method is firstly proposed by Yamaguchi, Peters W. Hand andRamson W. F in 1982. The first person who studied on the method in our country isGaoJianxin. In recent years, with the development of computer technology, and theperfection of the image gathered equipment, the digital correlation method has beenimproved vastly. Taking the research fruits of this field as theoretics, making the domesticand foreign development of the digital level as the background, and for enhancing theprecision of the digital leveling system, this thesis makes research on the influence ofenvironmental conditions and the distance to the barcode positioning in digital leveling,and proposes sub-pixel positioning algorithm of the standard barcode basing on theprinciple of correlation. And establishing the mathematical relationship between the greyvalues and the equal -space, the height of the barcode(elevation) as well as the barcodeimage's.Reliability and precision are two important criterions which are used in weighing onealgorithm. In order to validate the performance of this positioning algorithm, I hadcompiled one new kind of simulation software of four periodic combined barcode which isbased on periodic combined code, by C++ language under VC++6.0 environment, and thencarried on the simulation experiment. On the foundation of simulation experiment, I hadalso carried on the experiment of the actual digital leveling. The simulation results and theactual experimental results all indicate that this algorithm can enhance the precision of thestandard leveling barcode positioning, and reduce the influence of environmental conditionto the digital leveling system.