A video signal representing rapid ball movement is produced from a series of source images. An initial image position for the moving ball is identified by, for each image, producing a difference image between sequential images. In the difference image, image elements representing a contents alteration below a threshold are allocated a first value, and those representing a contents alteration above or equal to the threshold are allocated a second value. A set of candidates is then identified, where each candidate is represented by a group of neighboring image elements that all contain the second value. The group must fulfill a ball size criterion. A ball selection algorithm selects an initial image position from the set of ball candidates. The ball is tracked, and a composite image sequence is generated wherein a synthetic trace representing the path of the moving ball is shown as successively added image data.