Currently, the security of large civil engineering structures 
more and more people's attention, health monitoring study civil 
engineering at home and abroad is one of the hot topics of research. 
After a hundred years of research, the traditional structural health 
monitoring theories and methods continue to improve, and now 
there have been a lot to be able to use the results of the actual 
engineering and have been widely applied to large bridges and 
other structures, but there is a lot of its own defect. With the 
development of computer technology, people began to use 
computer vision to health monitoring, and gradually formed a 
monitoring method of mechanical vision. This paper introduces the 
significance and application health monitoring methods, and some 
of the traditional health monitoring methods are introduced. Then 
reviewed the development and the use of machine vision health 
status monitoring, and finally to crack measuring, for example, 
using wavelet recognition method for image recognition and 
analysis of fracture.