On the basis of pavement image preprocessing, the paper starts with the classical edge detection method, researches two kinds of improved edge detection methods: Marr-Hildreth and Canny.

• 在对病害路面图像预处理的基础上，从经典的边缘提取方法入手，研究了Marr-Hildreth和Canny两种改进的边缘检测方法，其中Canny方法效果最好。