Alexandrina Orzan Adrien Bousseau Holger Winnemöller Pascal Barla Joëlle Thollot David Salesin Diffusion curves: a vector representation for smooth-shaded images. 2008 27 ACM Trans. Graph. 3 http://doi.acm.org/10.1145/1360612.1360691 db/journals/tog/tog27.html#OrzanBWBTS08