The [HitTrax] system consists of separate hardware and software components. The hardware, encased in the rectangular white box seen above, consists of three near-infrared cameras and two near-infrared LED arrays that better illuminate the ball. Like other motion-capture systems, multiple cameras track the ball as it crosses the camera volume. The location of the ball in each camera’s field of vision, combined with the known distances between each camera, are combined to measure the position of the ball in three dimensions.
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