When an output unit is capable of operation at a frame rate F and a resolution of x.times.y pixels, an imaging unit or an image input unit converts an image into an imaged frame in an internal data format having the frame rate F and a resolution of ix.times.jy pixels. An image converter converts the resolution of the imaged frame supplied from the imaging unit or the image input unit into a resolution that can be represented by the output unit, generating an output frame having x.times.y pixels. At this time, the image converter carries out predetermined resolution conversion based on a moving velocity of the image by blocks each having a predetermined size. Thus, such visual effect that an observer of the image of the output frame perceives the image at a resolution exceeding the actual resolution of the output frame is achieved.