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Bug#606882: ITP: snaphu -- Statistical-Cost, Netowrk-Flow Algorithm for Phase Unwrapping



Package: wnpp
Severity: wishlist
Owner: Antonio Valentino <antonio.valentino@tiscali.it>


* Package name    : snaphu
  Version         : 1.4.2
  Upstream Author : Curtis W. Chen
* URL             : http://www-star.stanford.edu/sar_group/snaphu
* License         : non-free (free for non-commercial applications)
  Programming Lang: C
  Description     : Statistical-Cost, Netowrk-Flow Algorithm for Phase Unwrapping

Two-dimensional phase unwrapping is the process of recovering
unambiguous phase data from a 2-D array of phase values known only
modulo 2pi rad.

SNAPHU is an implementation of the Statistical-cost, Network-flow
Algorithm for Phase Unwrapping proposed by Chen and Zebker. This
algorithm poses phase unwrapping as a maximum a posteriori probability
(MAP) estimation problem, the objective of which is to compute the most
likely unwrapped solution given the observable input data. Because the
statistics relating the input data to the solution depend on the
measured quantity, SNAPHU incorporates three built-in statistical
models, for topography data, deformation data, and smooth generic data.
The posed optimization problem is solved approximately with use of
network-flow techniques.

SNAPHU always produces complete unwrapped solutions, and, in our tests,
its accuracy is comparable to or better than that of other available
algorithms. As SNAPHU uses an iterative optimization procedure, its
execution time depends on the difficulty of the interferogram. In
single-tile mode the required memory is on the order of 100 MB per
1,000,000 pixels in the input interferogram.

The software is written in C and should run on most Unix/Linux
platforms. It is freely available to the public, subject to the
conditions outlined in the README file included with the distribution.



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