A semi-automatic relative calibration of a fixed and PTZ camera pair for master-slave control

A PTZ camera has the capability to cater to a much larger area of coverage when compared to a fixed field of view (FOV) camera. However, to utilize the full capability of a PTZ camera, it is necessary to have analytics to support event based autonomous camera control, such as automatic tracking of moving objects (people and vehicles), and zooming on to a face or car license plate to get a closer look. This is achieved by operating a PTZ camera in tandem with a fixed camera or a single PTZ camera operating stand alone under a master-slave control mode. One critical requirement of master-slave control operation is establishing a relative calibration between the master camera view and PTZ camera orientation parameters (pan, tilt and zoom angles). This paper presents a semiautomatic approach for solving relative calibration between the master and slave camera pairs that can be used in field with minimum effort.