An image processing method of generating a range image, the method comprising: detecting a distance to an object as a measured distance, by a laser radar distance measurement unit; performing, by an image processing unit, matching of a stereogram by shifting a reference image, to calculate matching cost values of a plurality of pixels, wherein each of the matching cost values corresponds to a respective shift amount of a pixel between the reference image and a comparison image, converting, by the image processing unit, the matching cost values each corresponding to the respective shift amounts into a set of matching cost values each corresponding to a corresponding distance, wherein interpolation is used to obtain matching cost values for a uniform density of corresponding distances; performing, by the image processing unit, integration of the distance with the matching cost value of a pixel in the stereogram corresponding to an emitting direction of a laser of the laser radar distance measurement unit, among a plurality of pixels in the stereogram each including a corresponding matching cost value, wherein the integration includes integrating a distance evaluation value related to the measured distance, with a matching cost value corresponding to the measured distance among the matching cost values of said pixel, wherein the distance evaluation value is expressed as a first function of a length between said pixel and a surrounding pixel of said pixel, and wherein, in integrating the distance evaluation value, a value of the first function is added to a matching cost value corresponding to the measured distance among matching cost values of the surrounding pixel; and generating, after the integration, a range image for measuring a distance to an object, based on a result of the integration for a plurality of pixels. detecting a distance to an object as a measured distance, by a laser radar distance measurement unit; performing, by an image processing unit, matching of a stereogram by shifting a reference image, to calculate matching cost values of a plurality of pixels, wherein each of the matching cost values corresponds to a respective shift amount of a pixel between the reference image and a comparison image, converting, by the image processing unit, the matching cost values each corresponding to the respective shift amounts into a set of matching cost values each corresponding to a corresponding distance, wherein interpolation is used to obtain matching cost values for a uniform density of corresponding distances; performing, by the image processing unit, integration of the distance with the matching cost value of a pixel in the stereogram corresponding to an emitting direction of a laser of the laser radar distance measurement unit, among a plurality of pixels in the stereogram each including a corresponding matching cost value, wherein the integration includes integrating a distance evaluation value related to the measured distance, with a matching cost value corresponding to the measured distance among the matching cost values of said pixel, wherein the distance evaluation value is expressed as a first function of a length between said pixel and a surrounding pixel of said pixel, and wherein, in integrating the distance evaluation value, a value of the first function is added to a matching cost value corresponding to the measured distance among matching cost values of the surrounding pixel; and generating, after the integration, a range image for measuring a distance to an object, based on a result of the integration for a plurality of pixels.