In this work we propose a convex relaxation approach
for computing minimal partitions. Our approach is based
on rewriting the minimal partition problem (also known as
Potts model) in terms of a primal dual Total Variation functional.
We show that the Potts prior can be incorporated
by means of convex constraints on the dual variables. For
minimization we propose an efficient primal dual projected
gradient algorithm which also allows a fast implementation
on parallel hardware. Although our approach does not
guarantee to find global minimizers of the Potts model we
can give a tight bound on the energy between the computed
solution and the true minimizer. Furthermore we show that
our relaxation approach dominates recently proposed relaxations.
As a consequence, our approach allows to compute
solutions closer to the true minimizer. For many practical
problems we even find the global minimizer. We demonstrate
the excellent performance of our approach on several
multi-label ...