# Polygonal Approximation of an Object Contour by Detecting Edge Dominant Corners using Iterative Corner Suppression

### Rabih Al Nachar, Elie Inaty, Patrick J. Bonnin, Yasser Alayli

#### Abstract

A new algorithm to detect straight edge parts which form the contour of an object presented in an image is discussed in this paper. This algorithm is very robust and can detect true straight edges even when their pixel's locations are not straight due to natural noise at the object borders. These straight edges are than used to report and classify contour's corners according to their angle and their adjacent segments lengths. A new technique for polygonal approximation is also presented to find the best set among these corners to construct the polygon vertices that best describe the approximating contour. It starts by eliminating the corners, one after the other using Iterative Corner Suppression (ICS) process. This in turn enables us to obtain the smallest possible error in the approximation. Experimental results demonstrate the efficiency of this technique in comparison with recently proposed algorithms.

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#### Paper Citation

#### in Harvard Style

Al Nachar R., Inaty E., J. Bonnin P. and Alayli Y. (2014). **Polygonal Approximation of an Object Contour by Detecting Edge Dominant Corners using Iterative Corner Suppression** . In *Proceedings of the 9th International Conference on Computer Vision Theory and Applications - Volume 1: VISAPP, (VISIGRAPP 2014)* ISBN 978-989-758-003-1, pages 247-256. DOI: 10.5220/0004650602470256

#### in Bibtex Style

@conference{visapp14,

author={Rabih Al Nachar and Elie Inaty and Patrick J. Bonnin and Yasser Alayli},

title={Polygonal Approximation of an Object Contour by Detecting Edge Dominant Corners using Iterative Corner Suppression},

booktitle={Proceedings of the 9th International Conference on Computer Vision Theory and Applications - Volume 1: VISAPP, (VISIGRAPP 2014)},

year={2014},

pages={247-256},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0004650602470256},

isbn={978-989-758-003-1},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 9th International Conference on Computer Vision Theory and Applications - Volume 1: VISAPP, (VISIGRAPP 2014)

TI - Polygonal Approximation of an Object Contour by Detecting Edge Dominant Corners using Iterative Corner Suppression

SN - 978-989-758-003-1

AU - Al Nachar R.

AU - Inaty E.

AU - J. Bonnin P.

AU - Alayli Y.

PY - 2014

SP - 247

EP - 256

DO - 10.5220/0004650602470256