frequently applied feldkamp algorithm described in 1 filters the detector data one dimensionally row by row i e the filter lines are oriented along the detector rows in the case of the algorithms for an exact reconstruction of cone beam data filter lines are generally not arranged along the detector rows as described for example in 2 to 6 l a feldkamp l c davis j w kress u201c practical cone beam algorithm u201d j opt soc am a 1 6 pages 612 619 1984 j pack f noo and h kudo u201c investigation of saddle trajectories for cardiac ct imaging in cone beam geometry u201d physics in medicine and biology 49 11 pages 2317 2336 2004 a katsevich u201c image reconstruction for the circle and line trajectory u201d physics in medicine and biology 49 22 pages 5059 5072 2004 a katsevich u201c image reconstruction for the circle and arc trajectory u201d physics in medicine and biology 50 10 pages 2249 2265 2005 b e nett t zhuang and g h chen u201c a cone beam fbp reconstruction algorithm for short scan and super short scan source trajectories u201d in fully 3d image reconstruction in radiology and nuclear medicine salt lake city utah usa jul 6 jul 9 2005 j pack and f noo cone beam reconstruction using 1d filtering along the projection of m lines inverse problems 21 3 pages 1105 1120 2005 j hsieh e chao j thibault b grekowicz a horst s mcolash and t j myers a novel reconstruction algorithm to extend the ct scan field of view medical physics 31 9 pages 2385 2391 2004 m zellerhoff b scholz e p r u00fchrnschopf and t brunner low contrast 3d reconstruction from c arm.