An image forming system includes: an image forming portion that forms an image on a paper; an image scanning portion that scans the image formed on the paper; and a processor that controls the image forming portion based on a scanned image obtained through scanning of the image scanning portion, in which the processor is configured to: specify, based on a first scanned image that is corresponding to a first image formed on a first paper by the image forming portion and that is obtained through scanning of the image scanning portion, a first deviation amount representing a magnitude of a deviation of the first image with respect to the first paper; specify a first correction amount for deviation correction applied when the first image is formed, based on first management information included in the first scanned image; calculate a second correction amount based on the first deviation amount and the first correction amount; embed second management information representing the second correction amount in a second image; and correct a position where the second image is formed on a second paper, according to the second correction amount.

An image reading apparatus is configured to read image data generated by reading a window within a junction of a carrier sheet and then to determine whether the target object is a carrier sheet, based on a total height of a first area and a plurality of second areas arranged with the first area therebetween in a transport direction as well as a first color width. In the first area, pixels in a second color are sequentially arrayed in the transport direction; in the second areas, pixels in a first color are sequentially arrayed in the transport direction; and the first color width indicates a length of an area in which a plurality of pixels in the first color are sequentially arrayed in a width direction.