author = {Luc Brun and Walter Kropatsch}, title = {Implicit encoding of combinatorial Pyramids}, booktitle = {Proceedings of the Computer Vision Winter Workshop}, pages = {49-54}, year = 2003, editor = {Ondrej Drbohlav}, address = {Valtice, Czech Reublic}, month = {February}, url = { article:=https://brunl01.users.greyc.fr/ARTICLES/cvww2003.pdf}, abstract = " An irregular pyramid consists of a stack of successively reduced graphs. Each smaller graph is deduced from the preceding one by the contraction or the removal of a set of edges. Using a fixed decimation ratio we need approximately O(log(image size)) graphs to encode the whole pyramid. A combinatorial map encodes a planar graph thanks to two permutations encoding the edges and their orientation around the vertices. We present in this article an encoding of a combinatorial pyramid which allows to fold the whole pyramid in the base level layer and provides at the same time a measure of the importance of every pixel. Any reduced combinatorial maps of the pyramid maybe directly retrieved from this encoding if needed.", theme = {hierarchical}