  We propose a new variational model for non-linear image fusion. Our approach
is based on the use of an osmosis energy term related to the one studied in
Vogel et al. (2013) and Weickert et al. (2013) The minimization of the proposed
non-convex energy realizes visually plausible image data fusion, invariant to
multiplicative brightness changes. On the practical side, it requires minimal
supervision and parameter tuning and can encode prior information on the
structure of the images to be fused. For the numerical solution of the proposed
model, we develop a primal-dual algorithm and we apply the resulting
minimization scheme to solve multi-modal face fusion, color transfer and
cultural heritage conservation problems. Visual and quantitative comparisons to
state-of-the-art approaches prove the out-performance and the flexibility of
our method.
