Sportstech [Sports Technology Football]

The cameras are connected to a powerful image-processing computer system, which tracks the movement of all objects on the pitch and filters out the players, referee and all other objects. All that's left is the ball and the system knows its three dimensional x-, y- and z-position to within a few millimeters in the coordinate system of the pitch. When the ball passes the goal line, the system sends a vibration and optical signal to the officials' watches. All camera images of every event are stored and can be replayed anytime.