A new edge detection method in image processing

The edge detection methods based on difference operation are used widely in image processing. It could detect the variation of gray levels, but it is sensitive to noise. In order to improve the ability of noise rejection, this paper proposed a ratio of gray levels between 2 successive image points to denote the variation of gray levels. Furthermore, the paper defined a ratio and an integer logarithm ratio of gray levels. Based on the integer logarithm ratio of gray levels, a new edge detection method was proposed. The advantage of the proposed detection method is that the sensitivity of edge detection can be adjusted by selecting parameter a easily. The experiment results have shown that the effectiveness of edge detection and the ability of noise rejection of the proposed edge detection method are better than that of the traditional ones based on the difference operation.