An Improved Algorithm for Subpixel Location of Circle Center

To obtain the center of a circle in the digital image with high precision is always the key issue in the target recognition and location. Starting from the subpixel edge location, a improved algorithm for obtaining the subpixel edge, in this paper, is first brought forward based on the geometrical feature of the center and gray-distributed characteristic of the practical image. Then, the center location is realized by the least square method. Several experiments are used to compare this new algorithm and currently existing algorithms, and through the results, it can be concluded that the improved algorithm has much higher location precision and better robustness.