一种改进的Canny边缘检测算法

图像中部分低强度边缘在梯度幅值特性上与噪声点十分相似,因此,传统Canny边缘检测算法在采用基于梯度幅值的双阈值法检测和连接边缘时,尽管抑制了噪声,但同时也损坏了部分低强度边缘.针对这一问题,提出了一种改进的Canny边缘检测算法,采用新的基于梯度方向的检测和连接方法取代了传统的双阈值法,充分利用了边缘点和噪声点在梯度方向特性上的差异,在抑制噪声的同时,有效保护了低强度边缘细节,具有优于传统Canny算法的性能.仿真研究也证明了该算法的有效性.

An Improved Canny Algorithm for Edge Detection

Because of the high similarity between the gradient magnitudes of low-contrast edge and noise,the conventional Canny algorithm for detection,which is based on the double-threshold to detect and connect edges,damages partly the low-contrast edge though it suppresses noise.An improved Canny algorithm is therefore proposed instead of the double-threshold one,which detects and connects the edges in accordance to the difference of the gradient direction between the edge and the noise,so as to protect efficiently the details of all low-contrast edges with the noise suppressed simultaneously.The new approach is thus superior to the conventional one.Simulation tests have verified the effectiveness of the improved Canny algorithm for edge detection.