Subpixel Edge Location Using Orthogonal Fourier-Mellin Moments Based Edge Location Error Compensation Model

In order to improve the edge location accuracy of vision measurements, this paper presents a compensation model for edge location calculation using the orthogonal Fourier-Mellin moments (OFMMs). The edge location error is the difference between the sampling edge location and the actual one which occurs when the edge location is not within the center pixel and pixel boundaries. We established a look-up table which as the compensation model to eliminate the error for OFMMs.Experimental results showed that the proposed model can be used to correct the error of edge location. The precision of 0.19 pixel by using OFMMs with the compensation model can be achieved. It can be concluded that the proposed method is an efficient approach to satisfy the practical requirements for high accuracy for edge detection.