PURPOSE: To easily change a correction data, by dividing and storing a fixed and an arbitrary correction data into a ROM and a RAM, and correcting them in two stages, at the time of performing a gradation processing in a digital picture processor.

CONSTITUTION: Gradation correction tables are stored in both a RAM 2 and a ROM 5. An input picture data is supplied as an address signal 6 by an address switching circuit 1, and is corrected at the RAM 2. A data signal 7 outputted from the RAM 2 is supplied to a ROM 13 and a ROM address signal 12 by a data switching circuit 3, and is corrected in two stages. The rewrite of the content of the RAM 2 is performed by switching the address switching circuit 1, and the data switching circuit, by an address signal 4, and a rewrite data signal 8. In this way, the correction of the fixed correction data such as the gamma value of an image pickup element is performed by the ROM 13, and that of the arbitrary correction data centering the gamma value, by the RAM 2.