01246nas a2200145   4500008004100000245006500041210006500106260000900171300001200180490000800192520075700200100001700957700001800974856010800992       2002                        eng d00aReconstruction of convex 2D discrete sets in polynomial time0 aReconstruction of convex 2D discrete sets in polynomial time  cJune  a223-2420 v2833 a<p>The reconstruction problem is considered in those classes of discrete sets where the reconstruction can be performed from two projections in polynomial time. The reconstruction algorithms and complexity results are summarized in the case of hv-convex sets, hv-convex 8-connected sets, hv-convex polyominoes, and directed h-convex sets. As new results some properties of the feet and spines of the hv-convex 8-connected sets are proven and it is shown that the spine of such a set can be determined from the projections in linear time. Two algorithms are given to reconstruct hv-convex 8-connected sets. Finally, it is shown that the directed h-convex sets are uniquely reconstructible with respect to their row and column sum vectors. <tt> </tt></p>1 aKuba, Attila1 aBalogh, Emese  uhttps://www.inf.u-szeged.hu/en/publication/reconstruction-of-convex-2d-discrete-sets-in-polynomial-time