.. _example_transform_plot_matching.py:


============================
Robust matching using RANSAC
============================

In this simplified example we first generate two synthetic images as if they
were taken from different view points.

In the next step we find interest points in both images and find
correspondences based on a weighted sum of squared differences of a small
neighborhood around them. Note, that this measure is only robust towards
linear radiometric and not geometric distortions and is thus only usable with
slight view point changes.

After finding the correspondences we end up having a set of source and
destination coordinates which can be used to estimate the geometric
transformation between both images. However, many of the correspondences are
faulty and simply estimating the parameter set with all coordinates is not
sufficient. Therefore, the RANSAC algorithm is used on top of the normal model
to robustly estimate the parameter set by detecting outliers.


.. image:: images/plot_matching_1.png
    :align: center


.. literalinclude:: plot_matching.py
    :lines: 23-



**Python source code:** :download:`download <plot_matching.py>`
(generated using ``skimage`` |version|)



**IPython Notebook:** :download:`download <./notebook/plot_matching.ipynb>`
(generated using ``skimage`` |version|)

