This paper describes a method for video-based motion path detection which is applied in the creation of an interactive artwork. The proposed algorithm, based on the Hough transform, detects parametric motion trajectories in real-time (10 fps). In order to detect people's motion under non-static background object occlusion we have also developed a video segmentation technique. The proposed interaction system adopts top-down camera view to extract spatiotemporal motion trajectories and discern predefined patterns of movement thus enabling the creation of new artistic choreographies. We present test results that illustrate the effectiveness of our method and discuss the practical applicability of our approach in other domains
