Research on Two-Dimensional Bar Code Positioning Approach Based on Convex Hull Algorithm

During the process of the recognizing two-dimensional bar code, the two-dimensional bar can be corrected further only after accurately positing bar code in original image. In this paper, in case of the two-dimensional bar data matrix, the concept of convex hull in computational geometry is used to locate bar code in the paper. The vertices in convex hulls are selected from the list of pixels in order to reduce the number of the pixel processed. At the same time, the positioning graphics features of data matrix is set as selecting conditions in order to get the vertices in convex hulls in the area of positioning two-dimensional bar code finally. This algorithm overcomes the shortcomings of traditional straight-line detection algorithm as a result of the overall detection and the need to a large number of memory space. The experimental results show that the algorithm can position the area of distorted or tilted two-dimensional bar code effectively. It can reduce accurate positioning time.