capturing, with a camera, an image of a range in which a plurality of first light sources and a plurality of second light sources are installed, wherein the plurality of first light sources are installed on a roadway and configured to display a first crosswalk by emitting light toward a first side and the plurality of second light sources are installed on the roadway and configured to display a second crosswalk by emitting light toward a second side, the second side being opposite to the first side;

acquiring and analyzing the image captured by the camera;

concealing the first crosswalk from the first side toward the second side while a pedestrian is crossing the roadway from the first side to the second side through the first crosswalk and the second crosswalk; and

concealing the second crosswalk after the pedestrian has crossed the roadway.