An Improved Algorithm of Edge Detection Based on Fuzzy Sets
图象模糊涟缘检测的改进算法

Edge detection is one of the most important techniques in image processing, it is often used in the field of image analysis and image recognition for many applications. Pan and King firstly presented an algorithm of edge detection based on fuzzy sets, this algorithm has been found for many successful applications in the area of pattern recognition and medical image procesing. In this paper, an improved algorithm of edge detection proposed by Pal and King is presented, and the approach of edge detection is also developed to be an automatic one. The steps of this approach can be summarized as follows:firstly, a threshold is selected in an image by using an automatic algorithm of thresholding; secondly, in order to extract the fuzzy property plane from the spatial domain, a new membership function based on the threshold is defined; thirdly, image enhancement is performed in the fuzzy domain by using fuzzy enhancement operator; then, the modified spatial domain is obtained; finally, the edge detection is executed using min or max operators. This algorithm is also extended to the edge detection of the multi-thresholds image. The effectiveness of the algorithm is experimentally demonstrated.