A one-dimensional Calibration object consists of three or more collinear points with known relative positions.
It is generally believed that a camera can be calibrated only when a 1D Calibration object is in planar motion or rotates
around a ¯ xed point. In this paper, it is proved that when a multi-camera is observing a 1D object undergoing general
rigid motions synchronously, the camera set can be linearly calibrated. A linear algorithm for the camera set Calibration
is proposed,and then the linear estimation is further re¯ ned using the maximum likelihood criteria. The simulated and
real image experiments show that the proposed algorithm is valid and robust.