Consistent symmetric axis method for robust detection of ellipses

Ellipse detection is an interesting issue in machine vision researches and many approaches have been suggested to determine the parameters. Recently, a symmetric axis method has been proposed to determine the centre of an ellipse, but other parameters are determined otherwise. A consistent symmetric axis method is proposed that utilises the information inherent in the symmetric axes throughout the entire process to compute all of the parameters. A closed-form solution is obtained, hence the calculation of the parameters is fast. In addition, since the determination of the symmetric axes involves a set of points on the ellipse, the procedure is robust. Experiments with disjoint ellipses, interacting ellipses, defective ellipses and real objects indicate the effectiveness of the proposed method both theoretically and practically