Patent ID: 7245870

Claim:
An image forming apparatus having a function for feeding mixed sheets of paper of a plurality of sizes and forming an image onto each paper, comprising: paper mixture information input means for inputting paper mixture information indicating which paper sizes exist in mixture in one print job; determination means for determining whether a first paper size and a second paper size exist in mixture in the print job or whether the first paper size and a third paper size exist in mixture in the print job based on the paper mixture information input by said paper mixture information input means, wherein a paper of the first paper size can be fed in any of long-edge feeding and short-edge feeding directions, the second paper size is larger than the first paper size and the third paper size is smaller than the first paper size; and paper feeding direction specifying means for, in the case where it is determined by said determination means that the first paper size and the second paper size exist in mixture in the print job, specifying a paper feeding direction for performing a paper feed in the long-edge feeding direction of the first paper and for, in the case where it is determined by said determination means that the first paper size and the third paper size exist in mixture in the print job, specifying the paper feeding direction for performing the paper feed in the short-edge feeding direction of the first paper, wherein a printing product which aligns the long-edge of the first paper size and the short-edge of the second paper size or a printing product which aligns the short-edge of the first paper size and the long-edge of the third paper size is produced.