SHEET PROCESSING APPARATUS AND PROGRAM

According to one embodiment, a sheet processing apparatus includes: an image acquiring device (110) configured to acquire a sheet image that is an image on a sheet (P); a setting portion (120) configured to set a reference area (55) in the sheet image acquired by the image acquiring device (110), wherein the setting portion (120) repeats moving the reference area (55) from a starting position to an end position in a first direction by a first moving width (Lx), and, upon the reference area (55) reaching the end position, moving the reference area (55) in a second direction intersecting the first direction by a second moving width (Ly); a degree of similarity calculating portion (130) configured to extract a feature from an image in the reference area (55) set by the setting portion (120), and calculate a degree of similarity between the extracted feature and a typical sheet pattern; a moving width calculating portion (140) configured to calculate the first moving width (Lx) and/or the second moving width (Ly) based on the degree of similarity calculated by the degree of similarity calculating portion (130); a position specifying portion (150) configured to specify a position at which the typical pattern of sheets is present in the sheet image based on a plurality of the degrees of similarity calculated by the degree of similarity calculating portion (130); and a kind of sheet discriminating portion (160) configured to discriminate a kind of the sheet (P) based on the sheet image at the position specified by the position specifying portion (150).