Abstract:

The main research is to get the distance by use of 3Dcamera. This article will explain some key technologies, such as camera calibration, stereo rectification, SAD(Sum of Absolute Differences), three-dimensional reconstruction and so on. The chessboard pictures are taken by the 3D camera from different angles, then saved to computer, and used to corner detection and camera calibration in order to get the parameters of the camera. Bouguet algorithm is selected as the stereo rectification algorithm. Stereo matching use SAD method. When we get the disparity map and the points clouds we start three-dimensional reconstruction work, then the distance between the target and camera is calculated based on similar triangles principle. The experiment is finished by OpenCV2.4.3(C++) and VS2010. This system only need an ordinary 3D-camera,which is not expensive. This system is time-saving and accurate when it is used.

Key words: OpenCV, sum of absolute differences（SAD）, stereo vision, three-dimensional reconstruction, distance measurement