Abstract: Device for segmenting data corresponding, for example to image sites, for transmitting and/or storing these images at a low rate. This device comprises a sub-assembly for initial segmentation into classes, supplying an initial set of labels. In two parallel paths (201, 202), a sub-assembly (200) determines conditional probabilities, notably on the basis of a propagation factor L whose parameters are defined by specific relations. These probabilities are used in a labelling sub-assembly (300) which supplies a new set of labels. Finally, a sequencing sub-assembly (400) determines the replacement of the initial set of labels at the input of the sub-assembly (200) by the new set and continues or, in contrast, discontinues this iterative process of determining new labels.