Search

The bisector function is an important tool for analyzing and filtering Euclidean skeletons. In this paper, we are proposing a new way to compute 2D and 3D discrete bisector function based on annuli. From a continuous point of view, a point that belongs to the medial axis is the center of a maximal ball that hits the background in more than one point. The maximal angle between those points is expected to be high for most of the object points and corresponds to the bisector angle. This logic is not really applicable in the discrete space since we may miss some background points that can lead to small bisector angles. In this work we use annuli to find the background points in order to compute the bisector angle. Our approach offers the possibility to change the thickness of the annulus at a given point and is thus flexible when computing skeletons. Our work can be extended to nD and we propose the nD algorithm. [ABSTRACT FROM AUTHOR]

• The body centered cubic grid is a viable alternative to the cubic grid. • A coordinate system provides one to one correspondence with the cubic grid. • Discrete analytical planes and spheres defined through double Diophantine inequalities. • Topological separation and connectivity properties depend on the chosen thickness. • Discrete analytical lines defined as the intersection of up to six plane. We propose a characterization of discrete analytical spheres, planes and lines in the body-centered cubic (BCC) grid, both in the Cartesian and in the recently proposed alternative compact coordinate system, in which each integer triplet addresses some voxel in the grid. We define spheres and planes through double Diophantine inequalities and investigate their relevant topological features, such as functionality or the interrelation between the thickness of the objects and their connectivity and separation properties. We define lines as the intersection of planes. The number of the planes (up to six) is equal to the number of the pairs of faces of a BCC voxel that are parallel to the line. [ABSTRACT FROM AUTHOR]