System for filming a video movie in a real space comprising: —a filming camera (9), —a sensor (16), —a computerized pinpointing module (27) for determining the location of the filming camera, —a monitoring screen (15), —a computerized compositing module (32) for generating on the monitoring screen (15) a composite image of the real image and of a projection of a virtual image, generated according to the filming camera (9) location data.