A Skeleton Extraction Framework Based on Inner-Product and Border Gap

A novel algorithm for skeleton extraction is proposed in the paper. By numbering object’s border elements on spatial position, the border gap (BG) of inner pixel of the object is calculated; an 8-connected medial-axis hierarchy is derived by the BG; a thinning method including slicing and counting is proposed to improve the processing speed; branches with minor importance are truncated by vector diversity Vd and length-width ratio (LWR) with support vector machine (SVM) classifier. Experiments demonstrate that the derived skeletons keep good connectivity, especially in long and narrow area.