Robust Real-Time Ellipse Detection by Direct Least-Square-Fitting
Jianping Wu · 2008
This paper presents a robust real-time algorithm to automatically detect and accurately locate ellipse objects in digital images. The algorithm consists of three steps. First the edge pixels are extracted using Canny edge detection algorithm and then a noise removal process is run to remove the non-ellipse edgepoints. In the second step, a direct least-square-fitting algorithm is used to calculate the ellipse parameters from each cluster of pixels. In the third step, a robust criterion is developed to identify valid ellipses. The algorithm is implemented in Visual C++ and tested on a laptop powered by an Intel Centrino Duo CPU at 1.8 GHz. The preliminary experiment shows the algorithmpsilas speed is 212 ms/images on average for image size of 640X480.