ITEM INSPECTION BY RADIATION IMAGING USING AN ITERATIVE PROJECTION-MATCHING APPROACH

摘要

A method and system for inspection of an item, and a use thereof, are presented. The method comprises acquiring a plurality of projection images of an item at a plurality of projection angles for performing a tomographic reconstruction of the item. A plurality of objects are detected in the tomographic reconstruction and each object has a generic shape described by a parametric three-dimensional numerical model. Said detection comprises determining initial estimates of position and/or orientation of each object and at least one geometrical parameter of the three-dimensional model for each object. The initial estimates are iteratively refining by using a projection-matching approach, in which forward projection images are simulated for the objects according to operating parameters of the radiation imaging device and a difference metric between acquired projection images and simulated forward projection images is reduced at each iteration step.