ABSTRACT

This chapter describes a class of combinatorial optimization methods for energy minimization called the graph cuts. It also describes the graph cut algorithm in the case of binary labels, which is the most fundamental case where the energy-minimization problem directly translates to the minimum-cut problem, and global minima can be computed in a polynomial time under certain condition called submodularity. For the binary case, it also describes the BHS algorithm, which can partially minimize even the energies that do not satisfy the submodularity condition, as well as the reduction of higher-order energies to first order. The chapter addresses graph cuts to minimize energies when there are more than two labels. One approach to this is to translate multilabel energies into binary ones. In some cases, the resulting problem is globally optimizable. Another way is the approximate algorithms to solve the multilabel problems by iteratively solving binary problems with graph cuts.