By two dimension motion estimation and computing the displaced frame difference,the motion object can be separated form the still background,and then morphological filtering is used to gain the better segmentation result.

Pseudo excitation method based on solving absolute displacement

In this paper, the general formulae of measuring absolute displacements by means of the realtivefringe numbers between different object points in double exposure holographic interferometry are presented.

This paper introduces the methods and principles of observing the absolute displacement value of the tunnel wall-rock by using the surveying rod combined with whole-station instrument s free establishment of station, and points out that the detecting system possesses the advantages of lower cost, convenient operation, and simple data processing, etc.