The search for fast and robust phase-unwrapping algorithms remains an important problem in the development of real-time interferometric systems. Our phase-unwrapping approach uses a spatial binary-tree image decomposition to permit maximum parallelism in implementation. At each node in the tree structure, a single unwrapping decision is made between two image blocks. The unwrapping rule is derived from a statistical-estimation framework. Specifically, a maximum-likelihood estimate of the demodulation term is used. This term can be viewed as that which minimizes a discontinuity-penalizing cost function. We show that the algorithm exhibits a high level of robustness. Quantitative measures of performance are provided, and many phase maps are shown for subjective evaluation.
© 1998 Optical Society of America
Russell C. Hardie, Md. Iqbal Younus, and James Blackshire, "Robust Phase-Unwrapping Algorithm with a Spatial Binary-Tree Image Decomposition," Appl. Opt. 37, 4468-4476 (1998)