Phase Unwrapping by Accumulation of Residual Maps

We present a path independent (global) algorithm for phase unwrapping based on the minimisation of a robust cost function. The algorithm incorporates an outlier rejection mechanism making it robust to large inconsistencies and discontinuities. The proposal consists on an iterative incremental scheme that unwraps a sub–estimation of the residual phase at each iteration. The sub–estimation degree is controlled by an algorithm’s parameter. We present an efficiently computational multigrid implementation based on a nested strategy: the process is iterated by using multiple resolutions. The proposal’s performance is demonstrated by experiments with synthetic and real data, and successfully compared with algorithms of the state of the art.