Patent ID: 8259340

Claim:
A method for forming images on sheets, the sheets being folded and the sheets including at least an inside sheet and an outside sheet, comprising: judging whether a trimming process of the sheets is to be performed; determining, when it is judged that the trimming process of the sheets is to be performed, image forming areas of the images to be formed so that an image forming area of the image on the inside sheet is more interior than the image forming area of the image on the outside sheet; setting whether part of at least one image of the images is to be formed or the at least one image of the images is to be reduced; forming, when the at least one of the images to be formed is larger than the determined image forming area and it is set in the setting step that the part of the at least one image is to be formed, the part of the at least one image; and reducing, when the at least one of the images to be formed is larger than the determined image forming area and it is set in the setting step that the at least one image is to be reduced, the at least one image and forming the reduced image.