Extremal points: definition and application to 3D image registration

This paper presents the extraction of feature points, geometrically invariant, which can be used as reliable landmarks for registration and recognition. Mainly we show that it is possible to extract automatically feature lines and points from 3D images, which are robust and invariant with respect to rigid transforms, and enough precise to perform the automatic registration. This extends the possible applications of “the Marching Lines” algorithm, previously described for extremal lines extraction. We introduce here a new kind of feature points: the Extremal Points, belonging to the extremal lines, which allow us to find a point to point correspondences between 3D images of the same subject. We present also experimental results of automatic registration with real data, which demonstrate the remarkable stability of those points