When necessary process times in a reception apparatus for a determination on a change area, a determination on the color of the change area, and a decoding of bit data stream exceed a predetermined time from a frame acquiring timing, and a process delay would occur, an image generator acquires a frame. In addition, a decoder temporarily stores the frame in a memory, and thereafter at a predetermined timing performs the determination on the change area, the determination on the color of the change area, and the decoding of the bit data stream.