An object tracking system includes a sensor and a controller. The sensor captures frames for a global plane for at least a portion of a space. The controller has a memory that stores a homography associated with the sensor and a processor. The processor receives a first frame from the sensor and identifies a pixel location within the first frame. The processor determines an estimated sensor location for the sensor by applying the homography to the pixel location, and determines a location difference between the estimated sensor location and an actual sensor location for the sensor. The processor then compares the location difference to a difference threshold level, and recomputes the homography in response to determining that the location difference exceeds the difference threshold level.