EXPANDED PICTURE PROCESSING UNIT

摘要

PURPOSE:To prevent pseudo data or the like from being displayed on a monitor by transferring background data stored in an address to which pseudo data are to be stored to a save address, storing picture data including the pseudo data in the address and transferring again the background data to the storage address of the pseudo data. CONSTITUTION:Before picture data in a companding area are stored to an address to which picture data in the companding area are to be stored among addresses on which background data are stored, a save area arithmetic operation means 9 calculates a save area and a save address conversion means 10 converts the calculated area into the save address. Then a save transfer means 11 transfers the background data stored in a margin address to the save address in the background data stored in the storage means 6. Then data in the companding area are stored to the address designated by a picture data storage control means 5. Then a restoration transfer means 12 stores the background data from the save address to the margin address again.