Abstract: In order to overcome the shortcomings of traditional Hough transform in the circle detection, such as excessive computation, low precision of detecting concentric circles and low degree of automation, a circle detection algorithm based on connected region labeling algorithm is proposed. This new algorithm firstly solves the problem of excessive calculation which the traditional algorithm to process the image for the circle. Secondly, confirming the center and radius of the circle according to the characteristics, it avoids the detection problem of concentric circles. Finally, for the aim of automation, the 8 neighborhood pixels of the center of the circle are taken to determine the best and final circle. The experimental results show that the proposed algorithm can detect the circle accurately. Meanwhile, it’s less computational and more automated than the Hough transform.

Key words: Hough transform, connected region labeling algorithm, two-pass scanning, automation, circle detection

摘要： 针对传统Hough变换进行圆检测，计算量过大、检测同心圆精度不高、自动化程度低等缺点，提出一种基于连通区域标记算法的圆检测算法。该算法首先通过连通区域标记算法对图像进行处理得到一个圆，解决了传统Hough变换计算量过大的问题，再根据圆的特性确定其圆心及半径，从而避免了检测同心圆精度不高的问题。最后，分别取圆心的8邻域像素为圆心做圆，找到最优圆并将其与检测得出的圆进行比较来确定最终的圆，以达到自动化的目的。实验结果表明，提出的算法可以正确地检测出圆并具有很高的检测精度同时比Hough变换计算量小、自动化程度较高。

关键词: Hough变换, 连通区域标记算法, 两遍扫描法, 自动化, 圆检测