To provide an image-forming apparatus which can process to rotate images at a high speed when the images are to be processed to be rotated while being transferred between an image memory and an image rotation process part.

In transferring an image from a RAM 12, high-speed burst transfer (data transfer by a plurality of number of times after one designation of an address value) is carried out, and image data of a predetermined block size after rotated is transferred singly (data transfer by one time after one designation of the address value). The image is processed to be rotated at a high speed via a system bus 18 and an image bus 20.