Using the shape-matching method to compute sea-surface velocities from AVHRR satellite images

The idea of shape matching is applied to track edge features automatically in a pair of AVHRR IR satellite images. The centroid and radius weighted mean are chosen as shape-specific points of the edges in two sequential images. Through the correspondence of these two shape-specific points, the whole edge´s properties of rotation, translation, and scaling could be obtained. Also, a better correspondence in the second image is chosen according to the similarity comparison. After that, the total velocities of the points in the pattern can be computed. Velocity components in normal and tangential directions for certain points on the edge are also computed through a simple trial-and-error procedure and vector decomposition