Abstract Applying the fractional differential theory to image processing is a new research topic. According to the functional characteristics of fractional differential Tiansi operator, an algorithm is proposed to improve Tiansi operator. The algorithm significantly enhances the edge information value. It is based on the enhancement ability of fractional differential to image details and the mechanism analysis of fractional differential. Firstly, Tiansi template is divided into eight sub-templates with different directions around the detecting pixel, and then the eight weight sum values for the eight sub-templates are obtained. Next, the eight weights are divided into different groups. Consequently, three improved algorithms with different enhancing ranges are gained. Finally, the experimental results of edge enhancement show that the improve algorithm enhances edge information effectively and reveals more detailed information than traditional operators for rock fracture images.
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2010, Vol. 23 
