Quality-guided phase unwrapping technique: Comparison of quality maps and guiding strategies

School of Computer Engineering, Nanyang Technological University, Singapore.
Applied Optics (Impact Factor: 1.78). 11/2011; 50(33):6214-24. DOI: 10.1364/AO.50.006214
Source: PubMed


Quality-guided phase unwrapping is a widely used technique with different quality definitions and guiding strategies reported. It is thus necessary to do a detailed comparison of these approaches to choose the optimal quality map and guiding strategy. For quality maps, in the presence of noise, transform-based methods are found to be the best choice. However in the presence of discontinuities, phase unwrapping is itself unresolved and hence quality-guided phase unwrapping is not sufficient. For guiding strategies, classical, two-section, and stack-chain guiding strategies are chosen for comparison. If accuracy is the foremost criterion then the classical guiding strategy with a data structure of indexed interwoven linked list is best. If speed is of essence then the stack-chain guiding strategy is the one to use.

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Available from: Lei HUANG, Jan 07, 2015
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    • "The phase unwrapping process [1] [2] [3] [4] [5] [6] is an important stage for interferometric data processing, Synthetic Aperture Radar interferometry (SAR) [7] [8] [9] [10] [11] [12] [13] [14], Magnetic Resonance Imaging (MRI) [15], profilometry by fringe pattern projection [16], to mention just some applications . There are different approaches for phase unwrapping algorithms; some reviews on the topic are reported in [17] [18] [19] [20] and references therein. "
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