# CONCAVE HULL: A K-NEAREST NEIGHBOURS APPROACH FOR THE COMPUTATION OF THE REGION OCCUPIED BY A SET OF POINTS

### Adriano Moreira, Maribel Yasmina Santos

#### Abstract

This paper describes an algorithm to compute the envelope of a set of points in a plane, which generates convex or non-convex hulls that represent the area occupied by the given points. The proposed algorithm is based on a k-nearest neighbours approach, where the value of k, the only algorithm parameter, is used to control the “smoothness” of the final solution. The obtained results show that this algorithm is able to deal with arbitrary sets of points, and that the time to compute the polygons increases approximately linearly with the number of points.

#### References

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#### Paper Citation

#### in Harvard Style

Moreira A. and Yasmina Santos M. (2007). **CONCAVE HULL: A K-NEAREST NEIGHBOURS APPROACH FOR THE COMPUTATION OF THE REGION OCCUPIED BY A SET OF POINTS** . In *Proceedings of the Second International Conference on Computer Graphics Theory and Applications - Volume 1: GRAPP,* ISBN 978-972-8865-71-9, pages 61-68. DOI: 10.5220/0002080800610068

#### in Bibtex Style

@conference{grapp07,

author={Adriano Moreira and Maribel Yasmina Santos},

title={CONCAVE HULL: A K-NEAREST NEIGHBOURS APPROACH FOR THE COMPUTATION OF THE REGION OCCUPIED BY A SET OF POINTS},

booktitle={Proceedings of the Second International Conference on Computer Graphics Theory and Applications - Volume 1: GRAPP,},

year={2007},

pages={61-68},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0002080800610068},

isbn={978-972-8865-71-9},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the Second International Conference on Computer Graphics Theory and Applications - Volume 1: GRAPP,

TI - CONCAVE HULL: A K-NEAREST NEIGHBOURS APPROACH FOR THE COMPUTATION OF THE REGION OCCUPIED BY A SET OF POINTS

SN - 978-972-8865-71-9

AU - Moreira A.

AU - Yasmina Santos M.

PY - 2007

SP - 61

EP - 68

DO - 10.5220/0002080800610068