When a line number counted by a line number counting unit corresponds to a prescribed line number, a transfer source address generating unit adds an offset address set in an offset address setting unit to respective transfer source addresses to output as addresses to a memory. A DMA control unit controls DMA transfer in accordance with a transfer source address generated by the transfer source address generating unit and a transfer destination address generated by a transfer destination address generating unit. Thus, rapid enlargement/reduction of image data becomes possible.