Decomposing and Sketching 3D Objects by Curve Skeleton Processing

A 3D object decomposition method is presented, based on the polygonal approximation of the distance labeled curve skeleton. Polygonal approximation is accomplished to divide each skeleton branch into a number of segments along which no significant changes exist as regards curvature or distance label. Each segment is interpreted as the spine of a simple region, which is characterized by i) absence of significant curvature changes along its boundary and ii) thickness that is either constant or evolves linearly along the region. Quantitative information on shape, size, position and orientation of a simple region can be easily derived from spatial coordinates and distance labels of the extremes of the associated spine. Simple regions associated to spines sharing a common extreme partially overlap with each other. Object decomposition into disjoint regions is obtained by suitably dividing each overlapping region among the simple regions including it.