Phase Unwrapping by Minimizing Kikuchi Free Energy

Phase unwrapping in L-dimensional topologies is an important problem that has several applications in radar and satellite imaging. Sum product algorithm (belief propagation) gives excellent results for the phase unwrapping problem. In this work, we present a gradient smoothing technique that uses higher order surface models to produce very smooth surfaces and report an improvement in the solution obtained. In a recent important work, Yedidia e&al have showed the theoretical connections between belief propagation algorithms and free energy in statistical physics. Based on this, we present a model that uses the Kikuchi technique to compute better posterior marginals than those produced by sum product algorithm.