Information processing method and apparatus for original image protection in a simple manner at a low cost. When data is stored, a desired key code is inputted from an operation unit. An address conversion unit converts an address from an address output unit designating a storage position of a frame memory into a physical address of the frame memory based on the input desired key code, and the data is stored into a storage area of the frame memory designated by the converted physical address. As the data stored in the frame memory is held in this manner, even if the data is read out, an original cannot be reproduced as long as address conversion algorithm is unknown. Further, before the key code inputted from the operation unit is sent to the address conversion unit, it is shuffled in a key register. Thus key code security is improved.