PURPOSE: To surely read a character from the stamp pattern of the seal of a date, etc.

CONSTITUTION: This reader is comprised of a stamp block extraction part 12 which extracts a stamp block including the stamp pattern of the seal stamped on a document from document image, a stamp image dividing part 16 which segments the stamp pattern in the stamp block extracted by the stamp block extraction part 12 and divides a recognition target part into prescribed numbers, a recognition dictionary 22 in which a dictionary design at every division pattern obtained by dividing the stamp pattern of the seal into the prescribed numbers is prepared in advance, a stamp division pattern recognizing part 20 which performs recognition at every division pattern obtained by the stamp image dividing part 16, and an answer conversion part 28 which introduces the character included in the stamp pattern of the document based on the recognition result of each division pattern by the stamp division pattern recognizing part 20.