The Optimization of Sub-pixel Edge Detection Algorithm with Gauss Interpolation
Gang Cheng · Journal of Xi'an Technological University · 2012
The traditional Gaussian interpolation algorithm used in image detection is not so accurate.The positioning accuracy changes with the different angles of positioning location.It also has the problem of low efficiency.Because of those above problems,the algorithm of Gaussian interpolation sub-pixel edge detection is optimized.This paper presents an improved algorithm: After obtaining pixel-accuracy edge of object to be measured by LOG operator,Hough transform is used to get the curve slope of the boundary line and the normal of the corresponding point on the edge;Taylor series interpolation in the normal direction is performed to obtain the gray values in the direction of the gradient under new coordinate system;Finally,sub-pixel relocation in the gradient direction is performed based on the Gaussian interpolation algorithm.Experimental results show that the improved method can get much better precision,higher efficiency than the traditional algorithm.The algorithm has an advantage of direction invariance.The precision of 0.05 pixels effectively improves the accuracy of image edge detection.With very good effect,The method is applied to the detection of tool geometry and visual equipment.