23 KB439 KB14 KB200020242001Brzoska, Jean-BrunoColeou, CecileFlin, FredericLamboley, PascalLesaffre, Bernardletnik:20številka:35 stranistr. 187-191ISSN:1580-3139COBISSID:16037593URN:URN:NBN:SI:doc-MBVZ9TH0enDruštvo za stereologijo in kvantitativno analizo slike, Medicinska fakultetaImage analysis and stereologyanaliza slikgeometrijaImage Processing, Computer-Assistedračunalniška tomografijaSlika, obdelava z računalnikomTomografija radiografska, računalniškaTomography, X-Ray Computedtridimenzionalni modeliComputation of normal vectors of discrete 3D objects: application to natural snow images from X-ray tomography|Estimating the normal vector field on the boundary of discrete 3D objects is essential for rendering and image measurement problems. Most of the existing algorithms do not provide an accurate determination of the normal vector fieldfor shapes that present edges. We propose here a new and simple computational method to obtain accurate results on all types of shapes whatever their degree of local convexity. The presented method is based on theanalysis of the gradient vector field of the distance map of the object. Some results on simulated data and snow images from X-ray tomography are presented and discussedTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaDruštvo za stereologijo in kvantitativno analizo slike