Video information terminal device and video display system

A video projection system, comprising:

• a storage unit which stores image information;
• a projection unit which projects the image information stored in the storage unit by projection light on a board or projects projection light not having the image information on the board;
• and
• a camera unit which captures letters or diagrams handwritten by a user on the board,
• wherein, before the camera unit captures letters or diagrams hand-written on the board by a user, the projection unit changes projection light from projection light for projecting the image information to projection light not having the image information,
• wherein after the camera unit captured the letters or the diagrams handwritten by a user, the projection unit projects the captured letters or the captured diagrams as a digital image,
• wherein brightness inverting processing for the captured letters or the captured diagrams is executed before the captured letters or the captured diagrams is projected, based on whether the letters or the diagrams handwritten on a blackboard or on a whiteboard.