Detection of Circular Arcs in a Digital Image Using Chord and Sagitta Properties

摘要

This paper presents a new technique for detection of digital circles and circular arcs using chord property and sagitta property. It is shown how a variant of the chord property of an Euclidean circle can be used to detect a digital circle or a circular arc. Based on this property, digital circular arcs are first extracted and then using the sagitta property, their centers and radii are computed. Several arcs are merged together to form a complete digital circle or a larger arc. Finally, a technique based on Hough transform is used to improve the accuracy of computing the centers and radii. Experimental results have been furnished to demonstrate the efficiency of the proposed method.