“…The deletion rules of existing parallel thinning algorithms are generally given by matching templates with specific and "built-in" endpoint characterizations [1,3,8,9,10,11,14,15,16,20] with the exceptions of some 3D fully parallel algorithms [17] and some 3D subfield-based thinning algorithms [12,13]. In this paper, we introduce a general scheme for 6-subiteration 3D parallel thinning that is based on our new sufficient conditions for topology preservation.…”