Preliminary ICP stage for data-thinning based on object geometry

Basically, the I CP algorithm steps are as follows: for each point i n the first set, match the closest point in the second set; estimate mapping parameters using the RMS cost function; transform points using estimated parameters; perform multiple iterations (reconnecting points, and so on). In this paper a preliminary data-thinning algorithm is proposed. It can help to speed up all ICP algorithm stages by reducing the amount of input data. The proposed algorithm is based on the human perception of objects geometry. A human often analyzes edges and corners of objects and does not pay attention to the inner parts of polygons when comparing two objects and looking for similar parts. The algorithm described in this article begins with a search of planes in point's cloud. Next, the search for intersection of the found planes is performed in order to extract object edges. Finally, the intersection of the edges help us to get object corners. Further, all points not belonging to the edges and corners are removed from the point cloud. In real objects polygons most often occupy a large part of the object, therefore the proposed algorithm allows to get rid of a large number of insignificant points.