A circle fitting-based method for computing parameters of circular arc in scanning engineering drawing

Arc segmentation is quite a challenging field in Graphics Recognition and the computation of the coordinates of centers and the radii of circular arcs is a crucial problem which has drawn much attention. Therefore this paper mainly discusses the application of circle fitting skill in scanning engineering drawings to determine correct coordinates of centers and radii. At first we should choose appropriate seed points and improve circle fitting algorithm of Instrumental Variable Estimator (IVE). Then we combine seed points and the improved IVE (IIVE) algorithm to calculate coordinates of centers and radii of circular arcs. In experimental section, the performance of JJVE and other two methods are compared by using classical experimental data and the coordinates of centers and radii are computed by employing the Arc Segmentation contest data. The results show that the proposed algorithm is very effective and efficient and the causes of the unsatisfactory results are analyzed.