The application of multi-sensor fusion, which aims at recognizing a state a
mong a set of hypotheses for object classification, is of major interest as
regards the performance improvement brought by the sensor complementarity.
Nevertheless this needs to take into account the more accurate as possible
information and take advantage of the statistical learning of the previous
measurements acquired by sensors. The classical probabilistic fusion metho
ds lack of performance when the previous learning is not representative of
the real measurements provided by sensors. The Theory of evidence is then i
ntroduced to face this disadvantage by integrating a further information wh
ich is the context of the sensor acquisitions. In this paper, we propose a
formalism of modeling of the sensor reliability to the context that leads t
o two methods of integration when all the hypotheses, associated to the obj
ects of the scene acquired by sensors, are previously learnt : the first on
e amounts to integrate this further information in the fusion rule as degre
es of trust and the second models the sensor reliability directly as mass f
unctions. These two methods are based on the theory of fuzzy events. Afterw
ards, we are interested in the evolvement of these two methods in the case
where the previous learning is unavailable for a hypothesis associated to a
n object of the scene and compare these two methods in order to deduce a gl
obal method of contextual information integration in the fusion process.