.. _`Corner detection`:

.. _`syip.corner_detection`:

Corner detection
````````````````

.. image:: image_corners.svg
   :width: 48


Detects corners in the incoming image




Documentation
:::::::::::::

Algorithms
==========

    **FAST**
        Corner detection using the FAST (Feature from Accelerated Segment Test) method.


        :n: Number of points out of 16 that should be all brighter ordarker than test point. (default 12)

        :threshold: Threshold used in determining wheter the pixels are darker orbrighter (default 0.15).
            Decrease threshold when more corners are desired


        More info: http://scikit-image.org/docs/0.13.x/api/skimage.feature.html#skimage.feature.corner_fast

    **harris**
        Compute corner harris response image.


        :harris method: Method to compute response image from auto-correlationmatrix

        :k: Sensitivity factor to separate corners from edges, typically in range [0, 0.2]. Small values of k result in detection of sharp corners.

        :eps: Normalisation factor (Nobles corner measure)

        :sigma: Standard deviation used for the Gaussian kernel, which is used as weighting function for the auto-correlation matrix.


        More info: http://scikit-image.org/docs/0.13.x/api/skimage.feature.html#skimage.feature.corner_harris

    **KR**
        Compute Kitchen-Rosenfeld corner measure response image


        :k: Value outside image borders when method constant is used.

        :border mode: Method for handling values outside the borders


        More info: http://scikit-image.org/docs/0.13.x/api/skimage.feature.html#skimage.feature.corner_kitchen_rosenfeld

    **moravec**
        Compute Moravec corner measure response image.

         This is one of the simplest corner detectors and is comparatively fast but has several limitations (e.g. not rotation invariant).


        :window size: Size of window used during calculations


        More info: http://scikit-image.org/docs/0.13.x/api/skimage.feature.html#skimage.feature.corner_moravec

    **ST**
        Compute Shi-Tomasi (Kanade-Tomasi) corner measure responseimage. Uses information from auto-correlation matrix


        :sigma: Standard deviation used for the Gaussian kernel, which is used as weighting function for the auto-correlation matrix.


        More info: http://scikit-image.org/docs/0.13.x/api/skimage.feature.html#skimage.feature.corner_shi_tomasi


Definition
::::::::::


Input ports
===========

    **source**  image
        source image to filter


Output ports
============

    **result**  image
        result after filtering




Configuration
=============

    **Algorithm** (algorithm)
        (no description)
    **border mode** (border mode)
        (no description)
    **eps** (eps)
        (no description)
    **harris method** (harris method)
        (no description)
    **k** (k)
        (no description)
    **n** (n)
        (no description)
    **sigma** (sigma)
        (no description)
    **threshold** (threshold)
        (no description)
    **window size** (window size)
        (no description)









Implementation
==============

.. automodule:: node_detection_filters
    :noindex:

.. class:: CornerDetection
    :noindex: