Abstract: In an optical tracking system utilizing a TV camera, a method and apparatus for effectively removing the background of the scene and passing only target information to the tracking system. The analog video signal from the camera is converted to a 6-bit byte digital bit stream and top and bottom scanning lines representative of the background are stored. Scanning lines containing target data are compared to the stored lines and are converted to a serial digital bit stream having a ZERO base line representative of the background and variable width ONEs representative of the target. The centroid of the target is calculated and utilized to generate a tracking error between the centroid and the camera boresight.