Abstract
This paper describes a method for extracting elliptical figures in an image by the Hough transformation. We overcome the dimension problem inherent to the Hough transformation by decomposing the five-dimensional Hough transformation space into three sub-spaces based on the edge vector field properties of ellipses. A peak in a sub-space represents a group of ellipses which have the same geometric property. By sequentially selecting the peaks in the three sub-spaces we can extract elliptical figures.
Experiments using images of machine parts show that this method extracts ellipses of various shapes under practical conditions.
