Patent ID: 8269848

Claim:
In a camera calibration method for performing calibration to a camera image taken by a camera mounted on a movable base for projecting three-dimensional space onto two-dimensional image, the camera calibration method comprising placing planar calibration indices including actual coordinate information of at least four known points in a coordinate system based on said movable base, on a first plane in said three-dimensional space, inputting an image plane of said camera image including said calibration indices as a second plane, specifying points existing on said second plane and corresponding to predetermined portions of said calibration indices, and computing homography between said first plane and said second plane, on the basis of the corresponding relationship of said at least four points included commonly in said first plane and said second plane, wherein the homography is computed based on the relationship between the actual coordinate information and said camera image without using intrinsic and extrinsic parameters of the camera, obtaining a transforming relationship between the coordinate on said first plane in said three-dimensional space and the image coordinate on said second plane corresponding to the plane of said two-dimensional image, on the basis of the homography, and calibrating the camera image on the basis of the transforming relationship.