Model based estimation of point correspondences between boundaries undergoing nonrigid motion [digital mammography application]

Proposes a method for the estimation of point correspondences between boundaries undergoing nonrigid motion. The algorithm works in two stages. In the first stage, a global estimate of the nonrigid motion is obtained using hyperquadric models. The second stage uses this estimate to remove the global nonrigid motion (scale, shear, etc.) and then compute point correspondences between the two datasets assuming small deformations. The global part of the nonrigid motion (scale, shear, rotation and translation) is estimated by modeling the object with hyperquadrics and estimating the transformation between the hyperquadric parameters. Point correspondences are then estimated by using differential geometric properties during small deformations. Experimental results with real data are presented