分析和比较了三种常见的基于矩的亚像素边缘定位方法,得出三种方法获取的边缘角度以及OFMM法与ZOM法获取的亚像素边缘相同的结论。提出了一种针对椭圆目标的亚像素边缘定位方法。在ROI提取和SOBEL算子初步检测边缘的基础上,利用初步获取的椭圆目标的几何信息,将参与计算的模板个数减少至一个,从而大大减少了运算时间,提高了算法的运算速度。同时实验结果表明,与其他基于矩的亚像素边缘定位方法相比,新方法不仅有更高的运算速度,而且精度和抗噪性能都有很大地提高。

Analysis and comparisons for three common methods for sub-pixel edge location based moment are made. The results of edge-angle computed by the three moment-based methods are all the same. Moreover, the results of sub-pixel edge location computed by OFMM method and ZOM method are also the same. A novel method for sub-pixel edge of ellipse is proposed. Based on ROI extraction and coarsely edge-location by SOBEL operator, the geometric information of the target is used to reduce the number of moment-template to be only one, which can largely save the time. From the results both in simulation and practical experiments, the proposed method not only has greater computing speed, but also has a great advantage over other methods in precision and anti-noises.