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Mean-field annealing for phase unwrapping
Applied Optics, 1999Use of mean-field annealing theory is proposed for solving the phase-unwrapping (PU) problem. PU is formulated as a constrained optimization problem for the field of integer corrections to be added to the wrapped gradient field. A deterministic algorithm is described to provide an approximation of the average of the correction field over the global ...
Stramaglia S +3 more
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Analysis of the phase unwrapping algorithm
Applied Optics, 1982Several workers have recently proposed digital techniques for high-resolution imaging through the turbulent atmosphere. The basic concept of these algorithms is to calculate and average phase angles of a series of image Fourier transforms to suppress the unwanted atmospheric effects on image resolution.
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Robust phase-unwrapping techniques: a comparison
Journal of the Optical Society of America A, 1996In this paper we demonstrate the theoretical equivalence of two robust techniques for two-dimensional phase unwrapping. The first is based on the least-squares (LS) approach, and the second is based on Green’s formulation. To be theoretically comparable with Green’s method, the LS phase unwrapping is formulated in the continuous domain, leading to the ...
G Fornaro +3 more
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Phase unwrapping with differential phase image
SPIE Proceedings, 2017Phase unwrapping is the procedure of recovering the true phase from the modulo- 2π phase. It is needed for many applications such as Interferometric synthetic aperture radar, MRI and X-ray phase imaging etc. Many phase unwrapping methods have been proposed for two dimensional phase image.
S. Lian, H. Kudo
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Hierarchical quality-guided phase unwrapping algorithm
Applied Optics, 2019A hierarchical quality-guided phase unwrapping algorithm in a shared memory environment is proposed. First, the wrapped phase is divided into regular blocks, and local wrap counts of every block are obtained by a quality-guided strategy. Then, the gradient of the block wrap counts of adjacent blocks and the quality of every block are defined by the ...
Heping Zhong +3 more
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Phase Unwrapping for Magnetic Resonance Thermometry
2001Magnetic resonance thermometry enables temperature measurement in a noninvasive way. A representation oft he temperature is given by the phase shift ofthe MR signal[1]. Unfortunately, only “wrapped phase” is measured directly, yielding values between -π and +π. However only the true phase(“unwrapped phase”) is proportional to temperature.
Suprijanto, - +4 more
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SPIE Proceedings, 1987
An algorithm has been developed for phase unwrapping data that has significant noise content or phase variations. Existing unwrapping algorithms typically operate on a point by point basis. A faulty unwrapping decision will produce an error which will propagate through the rest of the array.
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An algorithm has been developed for phase unwrapping data that has significant noise content or phase variations. Existing unwrapping algorithms typically operate on a point by point basis. A faulty unwrapping decision will produce an error which will propagate through the rest of the array.
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Path-independent phase unwrapping of subsampled phase maps
Applied Optics, 1996A technique for unwrapping subsampled phase maps is presented. The subsampled phase map is obtained by standard phase-shifting methods that use subsampled interferograms. The technique then estimates the wrapped local curvature of the subsampled phase map.
M, Servin, D, Malacara, F J, Cuevas
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Phase unwrapping with a regularized phase-tracking system
Applied Optics, 1998We develop a regularized phase-tracking (RPT) technique tounwrap phase maps. The phase maps that can be unwrapped with thisnew method may be bounded by arbitrarily shaped boundaries. Moreover, the RPT unwrapper has a higher noise robustness than previously reported phase-unwrapping schemes.
M, Servin +3 more
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An Improved Phase-Unwrapping Method for Unwrapped Phase based RFID Localization
2023 IEEE 13th International Conference on RFID Technology and Applications (RFID-TA), 2023Wenhe Wang +4 more
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