Reliability-Map-Guided Phase Unwrapping Method

Path-following algorithms are important components of phase unwrapping methods and present the merits of conciseness upon approach and efficiency during operation. These algorithms employ information from phase residues or data quality, typically in an independent mode for the difference between the distribution discreteness of residues and the distribution continuity of data quality values. Residues are a part of discontinuity boundaries, and poor data quality suggests where discontinuity boundaries lie; a combined application of these would result in better effects in unwrapping. In this letter, a novel priority-map-guided phase unwrapping method is proposed, and the proposed priority measure, which is called reliability, is a combination of the distance from residues and data quality. The definition of reliability ensures locations of long distances from residues and good data quality values with high priority in the unwrapping path, and locations near residues with poor data quality, which are liable to be discontinuity boundaries, are set as low priority. Such a priority map design provides a more reliable scheme than classic path-following algorithms. Through experiments and the resulting analysis, the robustness and efficiency of the proposed phase unwrapping method are demonstrated.