Study of Monocular Measuring Technique Based on Homography Matrix

Abstract

This paper presents a real-time and effective measuring technique to determine the location of moving object on a fixed plane using homography matrix with a single camera. Based on OpenCV, this paper firstly calibrates the camera’s intrinsic parameters, and then obtains homography matrix between the plane of moving object and the image through specific template, and meanwhile the origin position of plane coordinates and coordinate axis direction are gained. According to the camera perspective projection model, the actual coordinates of the moving object in the fixed plane can be calculated while the coordinates in the image are known. Using the research results in on-line location of mechanical parts shows that the system has high accuracy and its precision meets for practicality.