1. Method for encoding a digital image signal represented by a set of digital samples, at least part of the digital image signal being encoded by reference to a reference digital image signal, the method comprising applying a segmentor to said reference digital image signal to obtain subsets of digital samples and applying a same filter among a set of predetermined filters to each sample of a said subset of digital samples, said segmentor being a context function capturing local characteristics of said reference digital image signal, characterized in that the method comprises the following steps: selecting a subset of segmentors from a predetermined set of segmentors based upon at least one characteristic obtained from said reference digital image signal, determining one segmentor among said selected subset of segmentors to apply to said reference digital image signal, said one segmentor being determined by iteratively testing each segmentor of said selected subset of segmentors according to a selection criteria, and encoding an item of information representative of said segmentor determined.