Edge Detection Algorithm based on Difference of Gaussian for Visual Prosthesis

Edge detection is a critical processing strategy for visual prosthesis. An edge detection algorithm based on Gaussian difference for visual prosthesis is proposed. The approach is consistent with the response of visual receptive field in the human vision system (HSV). Due to the pseudo edges in the Gaussian difference algorithm, an improved structure of zero-crossing point detection with the comparison of threshold is adopted. The algorithm is realized by hardware circuits using Verilog-HDL and verified on the FPGA development platform. The results show that the algorithm can effectively detect the image edge features and improve the precision and continuity of edge. Meanwhile, the parallel hardware circuit improves the efficiency of this algorithm.