Synthetic interferogram example with different levels of phase noise added corresponding to simulated decreased coherence values and noise mitigation results by spatial sampling, DFT, and DWT. In the upper row, from left to right the interferograms with |γ| = 0.8, |γ| = 0.6, and |γ| = 0.4 are, respectively, shown. The second row reports the corresponding results obtained by spatial sampling technique. In the third row, the results of DFT are shown. Finally, in the last row the results of DWT are reported.