Construction of Sandwich Cover of Digital Objects

  • Apurba SarkarEmail author
  • Mousumi Dutt
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9448)


An algorithm to construct a minimum vertex cover of a digital object from its inner and outer isothetic covers such that it lies within the annular region bounded by its outer and inner isothetic covers is presented here which has \(O(\frac{n}{g}\log (n/g))\) time complexity, where n being the number of pixels on the contour of the digital object and g is the grid size. After constructing inner and outer covers [2, 3], a combinatorial technique is used to construct a sandwich cover. Sandwich cover reduces the storage complexity of the given digital object as it contains less number of vertices compared to inner or outer isothetic cover while preserving the shape of the object. Sandwich cover can be used as shape descriptor by generating several metrics on it.


Isothetic covers Sandwich cover Shape analysis Shape descriptor Combinatorial technique 


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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Department of Computer Science and TechnologyIndian Institute of Engineering Science and TechnologyShibpurIndia
  2. 2.Department of Computer Science and EngineeringInternational Institute of Information TechnologyNaya-RaipurIndia

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