Sparse Object Representations by Digital Distance Functions
In this paper, some methods for representing objects using path-based distances are considered. The representations can be used as anchor points when extracting medial representations of the objects. The distance transform (DT) is obtained by labeling each object element with the distance to the background. By local operations on the DT, different sets of anchor points can be obtained. We present two different methods based on local operations and prove that the representations are reversible, when this is the case. The methods are defined for weighted distances based on neighborhood sequences, which includes for example the well known cityblock and chessboard distances.
KeywordsDistance Function Local Maximum Anchor Point Object Representation Medial Axis
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