How To Install snaphu on Ubuntu 18.04
Introduction
In this tutorial we learn how to install snaphu on Ubuntu 18.04.
What is snaphu
snaphu is:
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.
There are many applications, like Magnetic Resonance Imaging (MRI), Synthetic Aperture Radar (SAR), fringe pattern analysis, tomography and spectroscopy, which as part of their fundamental operation depend upon the extraction of a phase signal from their input image. Usually the phase is available in a form that suffers from 2-pi phase jumps due to the use of the mathematical arctangent function, which produces an inherently wrapped output. This wrapped phase is unusable until the phase discontinuities are removed.
SNAPHU is an implementation of the Statistical-cost, Network-flow Algorithm for Phase Unwrapping particularly suitable for SAR interferometry applications. 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.
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.
There are three methods to install snaphu on Ubuntu 18.04. We can use apt-get, apt and aptitude. In the following sections we will describe each method. You can choose one of them.
Install snaphu Using apt-get
Update apt database with apt-get using the following command.
sudo apt-get update
After updating apt database, We can install snaphu using apt-get by running the following command:
sudo apt-get -y install snaphu
Install snaphu Using apt
Update apt database with apt using the following command.
sudo apt update
After updating apt database, We can install snaphu using apt by running the following command:
sudo apt -y install snaphu
Install snaphu Using aptitude
If you want to follow this method, you might need to install aptitude first since aptitude is usually not installed by default on Ubuntu. Update apt database with aptitude using the following command.
sudo aptitude update
After updating apt database, We can install snaphu using aptitude by running the following command:
sudo aptitude -y install snaphu
How To Uninstall snaphu on Ubuntu 18.04
To uninstall only the snaphu package we can use the following command:
sudo apt-get remove snaphu
Uninstall snaphu And Its Dependencies
To uninstall snaphu and its dependencies that are no longer needed by Ubuntu 18.04, we can use the command below:
sudo apt-get -y autoremove snaphu
Remove snaphu Configurations and Data
To remove snaphu configuration and data from Ubuntu 18.04 we can use the following command:
sudo apt-get -y purge snaphu
Remove snaphu configuration, data, and all of its dependencies
We can use the following command to remove snaphu configurations, data and all of its dependencies, we can use the following command:
sudo apt-get -y autoremove --purge snaphu
References
Summary
In this tutorial we learn how to install snaphu package on Ubuntu 18.04 using different package management tools: apt, apt-get and aptitude.
