Algorithm Reference
===================

Here is an overview of the available phase unwrapping algorithms in this
package. Scikit-image's unwrap algorithm is not rewritten here, it is just included
for convenience and comparison. It still only works on the CPU.

The links at the bottom of the page will bring you to a
mathematical description of each algorithm.

For an introduction to the Phase Unwrapping problem, see the excellent 1D and 2D
introductions written by Dr. Munther Gdeisat and Dr. Francis Lilley.
You can find them online with the titles:

- "One-Dimensional Phase Unwrapping Problem By Dr. Munther Gdeisat and Dr. Francis Lilley"
- "Two-Dimensional Phase Unwrapping Problem By Dr. Munther Gdeisat and Dr. Francis Lilley"


Overview
--------

.. list-table:: Algorithm overview
   :header-rows: 1
   :width: 100%
   :widths: auto

   * - Algorithm
     - Speed
     - GPU friendly
     - Handles discontinuity
     - References
   * - | LS Poisson
       | (:func:`xpunwrap.algo_ls_poisson<xpunwrap.algorithms.algo_ls_poisson>`)
     - very fast
     - excellent
     - poor
     - :ref:`Ghiglia & Pritt (1998) <ls_poisson_refs>`
   * - | LS Poisson (Periodic Grad)
       | (:func:`xpunwrap.algo_ls_poisson_pg<xpunwrap.algorithms.algo_ls_poisson_pg>`)
     - very fast
     - excellent
     - poor
     - :ref:`Ghiglia & Pritt (1998) <ls_poisson_pg_refs>`
   * - | Weighted LS
       | (:func:`xpunwrap.algo_ls_weighted<xpunwrap.algorithms.algo_ls_weighted>`)
     - medium
     - good
     - moderate
     - :ref:`D. C. Ghiglia & L. A. Romero (1994) <ls_weighted_refs>`, :ref:`Ghiglia & Pritt (1998) <ls_weighted_refs>`
   * - | Reliability Path (for comparison)
       | (:func:`xpunwrap.algo_skimage_unwrap<xpunwrap.algorithms.algo_skimage_unwrap>`)
     - medium
     - CPU-only
     - excellent
     - `skimage example <https://scikit-image.org/docs/stable/auto_examples/filters/plot_phase_unwrap.html>`_

.. toctree::
   :maxdepth: 1

   ls_poisson
   ls_poisson_pg
   ls_weighted