A new combinatorial characterization of a gray-tone image called Euler Vector is proposed. Euler number of a binary image is a well-known topological feature, which remains invariant under translation, rotation, scaling, and rubber-sheet transformation of the image. Euler vector comprises of a 4-tuple, where each element is an integer representing the Euler number of the partial binary image fo...

Median filters and rank-order filters are generally considered to be more time consuming than, e.g., averaging filters. With the new algorithm presented in this report the opposite turns out to be true. The median (or any other rank-order value) is obtained by examining the bits of the arguments columnwise starting with the most significant bits. Hardware implementations suitable for parallel p...

Background Brazil is a country of Portuguese colonization with massive numbers of immigrants and Portuguese descendants (25 millions). At least half of all Brazilian Y chromosomes are from Portuguese origin. Nevertheless, this population suffered miscegenation with native Indians and African descendants. African descendants Brazilians have 48% of non-African genes, probably from Portuguese asce...