DEVICE FOR MONITORING IMAGE OF GROUND SURFACE

PROBLEM TO BE SOLVED: To provide a device capable of efficiently and economically measuring changes on the surface of a slope. SOLUTION: The ground surface image monitoring device is provided with an image data input means 101 for inputting 1st and 2nd images as 1st and 2nd input (ground surface image data), a feature point specification means 102 and a reference point specification means 104 for respectively specifying plural feature points and reference points, a relative distance calculation means 106 for calculating the relative distance of each feature point to each reference point in each of the 1st and 2nd pictures, a characteristic equation calculation means 107 for calculating a characteristic equation from the relative distance on the 1st image and the relative distance on the 2nd image, and a feature point displacement calculation means 108 for calculating the displacement of each feature point by using the characteristic equation. Consequently, a comparatively accurate judging materials can be obtained in the case of observing/ judging the states of the ground surface.