Research of improved subpixel edge detection algorithm using Zernike moments

The principle of sub-pixel edge detection based on Zernike moments were introduced in this paper. With the consideration of the limitation of the sub-pixel edge detection algorithm by Ghosal, this paper combine original algorithm with Otsu threshold algorithm and an improved algorithm for edge detection is proposed. First of all, a mask of size seven by seven was calculated and Zernike moment was calculated. Secondly, the distance threshold and edge threshold were calculated by using the formula, and the best intensity of step was calculated by using Otsu method. Finally, a series of experiments were designed and implemented. The experiment results showed that the improved algorithm can effectively detect the image edge and the subpixel location is more accurate. It reduces the existence of false edge and enhances the practicality of the algorithm.