To display expanded image data of a resolution different from that of a display panel through effective use of the resolution of the display panel by outputting the data containing an expanded data group with a prescribed ratio when outputting input data as output data.

Inputted image data are expanded or reduced and displayed on a display panel 35. In the case of expansion, for example, the data of preceding and following rows are used in each N frames for the data of the rows to be expanded due to the expansion, the data of preceding and following columns are expanded in each M frames for the data of the columns to be expanded due to the expansion, and this operation is performed by frame rate control. Corresponding to serial data received from a data processing circuit 30 and the respective signals of horizontal blanking, vertical blanking and clock received from a timing signal generating circuit 10, a display panel 35 displays four pieces of different data wherein one piece of data is expanded over two frames in each N/2 frame.