Abstract

In a printer system non-coded digital images having a horizontal scan format are rotated into a vertical scan format for printing or other processing thereof. Rotation is accomplished by logically dividing the digital image into a plurality of sections, then rotating the scan direction of each section in sequence, then combining the rotated sections into the completed image. Each image to be rotated and which is in compressed form is temporarily stored in a file from which it is taken for decompression. The decompressed image is transferred for temporary storage in a memory, one section at a time, with the lines of multi-bit words comprising each section being sequentially entered in the memory in the horizontal scan format. Rotation of the section to a vertical scan format is accomplished by addressing the memory in such a manner that the multi-bit words of the section are sequentially transferred out of the memory in columns rather than rows. Sections transferred out of the memory are compressed and stored in the file where the adjacent boundaries thereof are electronically knitted together as may be required by the particular compression technique used.