Hierarchical ellipse detection algorithm based on local PCA Hough transform with parameter restraint
局部PCA参数约束的Hough多椭圆分层检测算法

Concerning the invalid sampling, invalid accumulations and long run time yielded by random sampling when Randomized Hough Transform (RHT) was introduced to detect circles and ellipses in complex images processing, a new method of hierarchical Hough ellipse detection with parameter restraint based on local PCA aiming at line segments of interest was proposed. Firstly through Canny method the edge image was obtained and the cross points were deleted. Then some useful segments were retained through PCA which were labeled and the coarse parameters could be computed by curve fit to restrain the search scope of Hough transform. Lastly the ellipse exact parameters were searched from small Hough parameter space, which updated the image space till all the ellipses were detected. Comparative simulation results show that the algorithm proposed in this paper is efficient in performance of speed.