  We discuss a method to reconstruct an approximate two-dimensional foam
structure from an incomplete image using the extended Potts mode with a pinned
lattice we introduced in a previous paper. The initial information consists of
the positions of the vertices only. We locate the centers of the bubbles using
the Euclidean distance-map construction and assign at each vertex position a
continuous pinning field with a potential falling off as $1/r$. We nucleate a
bubble at each center using the extended Potts model and let the structure
evolve under the constraint of scaled target areas until the bubbles contact
each other. The target area constraint and pinning centers prevent further
coarsening. We then turn the area constraint off and let the edges relax to a
minimum energy configuration. The result is a reconstructed structure very
close to the simulation. We repeated this procedure for various stages of the
coarsening of the same simulated foam and investigated the simulation and
reconstruction dynamics, topology and area distribution, finding that they
agree to good accuracy.
