Discrete Geometry for Computer Imagery 21st IAPR International Conference, DGCI 2019, Marne-la-Vallée, France, March 26-28, 2019, Proceedings - Couprie, Michel; Couprie, Michel; Cousty, Jean; Cousty, Jean; Kenmochi, Yukiko; Kenmochi, Yukiko; Mustafa, Nabil; Mustafa, Nabil (Springer International Publishing : Imprint: Springer, 2019)