New detection method of ellipse by using randomized Hough transform

When Randomized Hough Transform (RHT) is directly used to detect ellipses, five points are needed to be randomly sampled to determine the ellipse parameters, hence a large amount of useless accumulations are caused during processing complex images. To solve the problem, a new detection method of ellipse using RHT was proposed, which uses two randomly picked points (with edge directions) and one searched point to calculate the ellipse parameters. In doing so, only two points are randomly picked when the ellipse parameters are calculated, furthermore, the searched point can be used to determine whether the parameters should be accumulated or not, therefore, the problem of useless sampling and accumulations is well solved. In comparison with other detection methods, this method has the advantages of high speed, small storage and good detection performance.