1. Automatic description method for an unknown multimedia object in which the unknown object is associated with several types of reference multimedia objects each time depending on a probability of membership to each considered type (G), the method including a step consisting of measuring at least one physical characteristic on the unknown object (F) and comparing it with measurements of characteristics best representing the reference types, the method also including the step (H) consisting of using at least one probabilistic relation for each type giving a probability of membership to the type considered as a function of the result of the comparison of characteristics of the unknown object and the type, the method also including the step consisting of using probabilities of membership to the different types thus obtained in combination with a series of affinity relations between types, so as to elect memberships that are majority in probability and are also co-designated by their affinity relation, so as to exclude memberships with a lower affinity with elected types.