针对Harris算法检测角点存在偏差、运算慢、像素级精度难于满足实际应用需要等问题,改进了Harris角点检测方法。该方法在Harris提取角点过程中,通过两次角点筛选,剔除非角点和伪角点,利用角点响应函数执行非极大值抑制,以局部角点响应函数最大值的像素点作为初始角点,并以该初始角点为中心,以一定半径搜索角点簇,采用最小二乘法加权角点簇与待求角点的欧几里得距离,精化初始角点坐标,从而实现Harris亚像素角点准确快速定位。实验结果表明了该方法的有效性和实用性。

An improved algorithm for Harris rapid sub-pixel corner detection is proposed by considering the limitations of inaccurate localization and the low efficiency of the Harris algorithm. The improved algorithm is used to reject non-corners and false corners by screening the corners two times. After detecting the initial corners with the non-maximum suppression of the corners response function, the initial corners are refined to sub-pixel corners by the Euclidean distance between the corner cluster and an ideal corner using a weighted least squares method. The location of the initial corners are considered as the center of the searching corner cluster, and the value of the corners response function is considered as weight. Our tests show that the improved algorithm is effective and practical.