Patent ID: 6856698

Claim:
A method for refining an approximate pose of an object in an image, the object having an expected shape and a true pose in the image, the method comprising: storing a model pattern, said model pattern including a geometric description of the expected shape of said object, said geometric description including a plurality of pattern boundary points; providing a starting pose of the model pattern that represents an initial estimate of the true pose of said object in said image; detecting in said image a plurality of image boundary points; using said starting pose of the model pattern and said model pattern to determine an image boundary point weighting factor representing an evaluation of reliability for each image boundary point of at least a sub-plurality of said plurality of image boundary points, and to determine a corresponding position along a boundary of said model pattern corresponding to each image boundary point of at least a sub-plurality of said plurality of image boundary points; and computing a new pose of the model pattern using said starting pose of the model pattern, the plurality of image boundary points, image boundary point weighting factors of each of at least a sub-plurality of the plurality of image boundary points, and corresponding positions along said boundary of said model pattern for each image boundary point of at least a sub-plurality of the plurality of image boundary points, the new pose of the model pattern representing a more refined estimate of the true pose of said object in said image.