Patent ID: 7218773

Claim:
A pose estimation method by using a plurality of pose candidates, comprising the steps of: a) measuring reflectivity or color at every point of a reference object under varying illuminations to produce a plurality of illumination variations textures each representing a brightness value of said every point of the reference object, and calculating basis textures approximating said illumination variation textures; b) creating, for each of said pose candidates, an image space of basis images representing brightness values of a plurality of two-dimensional images of a target object which would be obtained if said target object were placed in the same position and orientation as said each pose candidate and illuminated under varying lighting conditions by projecting said basis textures onto image space of said pose candidates; c) detecting, for each of said pose candidates, an image candidate within said image space of basis images by using said basis textures and determining a distance from the image candidate to an input image of said target object; and d) selecting one of the pose candidates which corresponds to the image candidate whose distance to said input image is smallest.