Phase unwrapping method based on stochastic relaxation

We propose a new method for phase unwrapping based on Stochastic Relaxation. A cost functional is introduced as a measure of the smoothness of the unwrapped phase field. Hence the problem of reconstructing the unwrapped phase field can be formulated as a minimization problem for the integer deviations between the measured and the unknown neighboring pixel differences of the true phase, with the constraint that the deviations have to remove the inconsistencies of the measured phase differences. The optimization problem is solved by the simulated annealing with constraint technique. We tested our method on simulated and real interferograms in presence of aliasing and noise. We remark that our method does not remove noise: in the case of noisy phase fields, our method's output is very near to the input surface noise included. The consistency and efficiency of our method are also demonstrated by comparative test using least squares methods.