Robust Non-rigid Registration Algorithm Based on Local Affine Registration

To solve the problem that the traditional point set non-rigid registration algorithm has low precision and slow convergence speed for complex local deformation data, this paper proposes a robust non-rigid registration algorithm based on local affine registration. The algorithm uses a hierarchical iterative method to complete the non-rigid registration of the point set from coarse to fine. In each iteration, the sub shape point sets and sub target point sets are divided and the shape control points of each sub point set are updated. Then the control point guided affine Iterative Closest Point (ICP) algorithm is used to solve the local affine transformation between the corresponding sub point sets. Next, the local affine transformation obtained by the previous step is used to update the sub data point sets and their shape control point sets. Until the registration error converges, the loop ends and outputs the updated shape point set. Experimental results demonstrate that the accuracy and convergence of the proposed algorithm are greatly improved compared with the traditional point set non-rigid registration algorithms.