This repository contains code from our paper on 2D phase unwrapping.
Benjamin Dubois-Taine, Roland Akiki and Alexandre d'Aspremont. "Iteratively Reweighted Least Squares for Phase Unwrapping". In: arXiv preprint arXiv:2401.09961.
Once you have downloaded the repository, we suggest creating a conda environment named phase_unwrapping.
conda env create -f environment.yml
conda activate phase_unwrapping
We also provide a requirements.txt file for users wishing to use another virtual environment manager.
Once this is done, you need to compile SNAPHU. This step is not necessary if you plan to use your own weights or uniform weights in your objective function. However SNAPHU generated weights have shown good practical performance, so we encourage using them. In the root directory, run the following.
$ cd snaphu-v2.0.6
$ mkdir bin
$ cd src
$ make
To reproduce the experiments, run in the working directory:
$ python final_script.py
This will load simulated and real images from a region in Lebanon from the data folder. It will then unwrap the images using the IRLS algorithm, and write the output to a results folder.
To visualize the experiments, simply use the notebook visualize_results.ipynb.
For the experiments on real images, the plots should look like the following:
For the experiments on simulated images, the plots should look like the following:
To unwrap the image, you can use weights generated from the SNAPHU software. SNAPHU does not offer the option to only compute weights, so we slightly modifiy the original code and distribute it here. The copyright notice for the SNAPHU software is as follows:
Copyright
---------
Copyright 2002 Board of Trustees, Leland Stanford Jr. University
Except as noted below, permission to use, copy, modify, and
distribute, this software and its documentation for any purpose is
hereby granted without fee, provided that the above copyright notice
appear in all copies and that both that copyright notice and this
permission notice appear in supporting documentation, and that the
name of the copyright holders be used in advertising or publicity
pertaining to distribution of the software with specific, written
prior permission, and that no fee is charged for further distribution
of this software, or any modifications thereof. The copyright holder
makes no representations about the suitability of this software for
any purpose. It is provided "as is" without express or implied
warranty.
THE COPYRIGHT HOLDER DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
RESULTING FROM LOSS OF USE, DATA, PROFITS, QPA OR GPA, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
The parts of this software derived from the CS2 minimum cost flow
solver written by A. V. Goldberg and B. Cherkassky are governed by the
terms of the copyright holder of that software. Permission has been
granted to use and distrubute that software for strictly noncommercial
purposes as part of this package, provided that the following
copyright notice from the original distribution and URL accompany the
software:
COPYRIGHT C 1995 IG Systems, Inc. Permission to use for
evaluation purposes is granted provided that proper
acknowledgments are given. For a commercial licence, contact
igsys@eclipse.net.
This software comes with NO WARRANTY, expressed or implied. By way
of example, but not limitation, we make no representations of
warranties of merchantability or fitness for any particular
purpose or that the use of the software components or
documentation will not infringe any patents, copyrights,
trademarks, or other rights.
To cite our our work please use:
@article{dubois2024iteratively,
title={Iteratively Reweighted Least Squares for Phase Unwrapping},
author={Dubois-Taine, Benjamin and Akiki, Roland and d'Aspremont, Alexandre},
journal={arXiv preprint arXiv:2401.09961},
year={2024}
}