Camera Calibration For Industrial Measurement

Camera calibration originating from the photogrammetric technology, is a crucial problem more recently in modern computer vision. Much work on Camera calibration has been done, and many techniques and some studies concerning calibration have been presented in the last few years. However, it is still difficult to go into details of determination of calibration techniques and compare its accuracy with others. This problem emerges mainly from the lack of a standardized notation and the difference of various methods of accuracy evaluation to choose from.A detailed review of the most used calibrating techniques is presented, in which the principal idea has been described in the same notation. Furthermore, a simple and rapid method based on reconstructing a 3D reference point set for camera calibration is proposed, by means of which either the camera or the planar pattern can be freely moved, and the motion need not be known, and the intrinsic and extrinsic parameters of the camera can be easily obtained by setting the camera to a 2D pattern for analysis. Compared with classical techniques which use expensive equipment such as two or three orthogonal planes, the proposed technique is easy to be used and flexible.A feasible model of the system of light-section and image scanning used for volume measurement is given, in which just two parameters need to be calibrated. And a new method to calibrate the structure-light plane based on vanishing line is presented as well as calibration solution proposed.