Image forming apparatus containing erasable font pattern

Abstract

The image forming apparatus includes a receiver for successively receiving image data from an external device, a first memory for storing a basic font pattern, a second memory including a first memory area for storing a modified font pattern obtained by modifying the basic font pattern stored in the first memory, and a second memory area for storing bit image data, a generator for successively generating bit image data from the image data received by the receiver, using the basic font pattern stored in the first memory and the modified font pattern stored in the first memory area of the second memory, a first processor for expanding the bit image data generated by the generator into the second memory area of the second memory. The bit image data generated by the generator is expanded into the second memory area of the second memory. The second memory area, may be used up during the generated bit image expansion. The first memory area of the second memory is changed from a modified font pattern storage area, which is unused in the expanded bit image, to an additional bit image expansion area. The combination of the additional bit image expansion area and the second memory area of the second memory serve as a temporarily increased bit image expanding area.