In this paper

a contour based rigid registration method of multimodal medical images is pvesented. Based on the semiautomatic search of contour

by using iterative algorithm of closest points to find corresponding points

the cost function is minimized and a best transformation can be obtained

so that the images are registered precisely. Depending on the strategy of choosing initial transformations many a time

the local minimum problem in process of iterative detection have been solved. This method is proved to be effective on registration of multimodal medical images in our experiment.