Patent ID: 8620043

Claim:
An image processing apparatus comprising: a gradient strength calculating unit that calculates a gradient strength of a pixel value of each pixel based on an intraluminal image that is a captured image of an intralumen; a closed region extracting unit that extracts a closed region from the intraluminal image, the closed region satisfying conditions that the pixel of which gradient strength is a predetermined value or more is not included in the closed region and a boundary of the closed region does not bend with a predetermined curvature or higher toward an inner side of the closed region; and an abnormal portion detecting unit that detects an abnormal portion inside the closed region, wherein the closed region extracting unit includes an initial closed region setting unit that sets an initial shape of the closed region; an energy calculating unit that calculates values of a plurality of types of energy including at least energy determined by an outer shape of the closed region and energy determined by the gradient strength in the closed region; an energy-weighted sum calculating unit that calculates a weighted sum of the plurality of types of energy; and a closed region updating unit that updates a shape of the closed region within an update range based on the weighted sum, and the closed region updating unit includes an update range determining unit that determines the update range in which the shape of the closed region is updated based on any one of the values of the plurality of types of energy.