1. A method, comprising: performing by at least one processor: controlling a projector to project an image content onto a projection surface in a region defining a display area; receiving captured images captured by at least one optical sensor of the projected image content on the projection surface; detecting, in the captured images, user touches of a plurality of designated locations of the projected image content on the projection surface; determining a position of an interaction area based on the detected user touches; and determining, based on the determined position of the interaction area, whether the display area and the interaction area coincide.