Calcul De La Tangente D'une Courbe Discr Ete En Temps Optimal : Application a La Courbure
نویسندگان
چکیده
With the deenition of discrete line introduced by Reveilles REV91], there have been a wide range of research in discrete geometry and more precisely on the study of discrete line. By the use of the linear time line recognition algorithm of Debled and Reveilles DR94], A Vialard has proposed a O(n:l) algorithm for computing the tangent at all the points of a discrete curve. The complexity of her algorithm is govern by n the number of points of the curve and by l the average length of the tangent. This paper proposes a new appraoch for computing the tangent. It is based on a precise study of the tangent evolution along a discrete curve. The resulting algorithm has a complexity O(n) and is thus optimal. Some applications in curvature computation and tombstones contours studies are also presented.
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