It is difficult to recognize objects when they are distorted and partially occluded or broken. In order to solve this problem

a new registration algorithm is proposed in this paper. First

we define the CCCTI(cyclic code of corner and tangent and inflexion points) of a planar curve. This code can easily determine the corresponding relation of the key feature points between the model and target contour. Second

contours are segmented by using the key feature points

and the transformation matrix is estimated based on two endpoints of the sub-curve and its centroid. Then

all estimate matrices are clustered using hierarchical clustering method. This process can reduce the final error of the estimation matrix and improve the robustness of the algorithm

making the algorithm suitable for partial occlusions or broken objects. Finally

we calculate the total centroid of corresponding sub-curve segments

and estimate the transformation matrix again using the total centroid and two endpoints of the corresponding sub-curve segments

to improve the accuracy of the registration. The theoretical analysis and experimental results show that our algorithm can be effectively used for affine registration

and that it can deal with partial occlusions and broken objects.