The images, videos, flashes or other multimedia interactive effects are projected onto the floor or the wall by a projector. When the participants walk through the area covered by the projector, the participant's action could be integrated into the interactive effects by means of the vision recognition system. Thus, the participants' action could have real-time interaction with the pre-made images, videos, flashes and other effects. The changes of interactive images and sounds bring a kind of atmosphere which is different from the reality. Through above-mentioned interaction, participants could play virtual games, such as basketball, catching fishes, chess, ect. , to attract people's attention.