Patent ID: 7650047

Claim:
A method of extracting and outputting differences between captured images, comprising the steps of: inputting a first captured image and a second captured image which differ in captured time; extracting first foot-print information from the first captured image, wherein the first foot-print information comprises (1) a geometric property which includes a boundary property and an internal regional property, (2) an image property which includes a color property, and (3) a spatial property of at least one object in the first captured image; overlaying the first captured image on the second captured image based on characteristic points extracted from the first captured image by performing a geometric conversion on the second captured image to match the characteristic points in the first and second captured images; extracting an image area from the second captured image corresponding to an image area in the first captured image, by using first foot-print information; extracting second foot-print information from the extracted image area of the second captured image; and comparing the first foot-print information with the second foot-print information to extract differences between the first and second foot-print information, and outputting the differences as change information, including an image of the change information.