2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/18034We report results on the scaling properties of changes in contrast of natural images in different visual environments. This study confirms the existence, in a vast class of images, of a multiplicative process relating the variations in contrast seen at two different scales, as was found in \cite{NIPS97,TuMaPaNa98}. But it also shows that the scaling exponents are not universal: Even if most images follow the same type of statistics, they do it with different values of the distribution parameters. Motivated by these results, we also present the analysis of a generative model of images that reproduces those properties and that has the correct power spectrum. Possible implications for visual processing are also discussed.29 pages, 9 figures, LaTeX. Higher quality pictures can be requested from the authorsStatistical MechanicsDisordered Systems and Neural Networkstext