.. _`Filter image`:

.. _`syip.general_filters`:

Filter image
````````````

.. image:: image_filtering.svg
   :width: 48


Applies simple filtering or scaling algorithms on an image. For more complex operations see the more specialized image manipulation nodes




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

Algorithms
==========

    **abs**
        Computes absolute value or complex magnitude of image





    **angle**
        Gives the phase angle of a complex image





    **center image**
        Shifts image so that center of mass lies in center of image





    **clamp**
        Restricts the output values to a given maximum/minimum


        :minimum: The minimum output value that can be passed through

        :maximum: The maximum output value that can be passed through




    **gaussian**
        Two-dimensional Gaussian filter


        :sigma-x: Standard deviation of gaussian filter along X-axis

        :sigma-y: Standard deviation of gaussian filter along Y-axis

        :border mode: Determines how the array borders are handled

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


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

    **hessian determinant**
        Computes an approximation of the determinant of the hessian matrix for each pixel.


        :sigma: Standard deviation of gaussian kernel (default 3.0) used for calculating Hessian.
            Approximation is not reliable for sigma < 3.0


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

    **imag**
        Gives the imaginary part of a complex image





    **integral image**
        Creates the integral image of the input.
        An integral image contains at coordinate (m,n) the sum of all values above and to the left of it::

            S(m,n) = sum(im[0:m, 0:n])



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

    **normalize**
        Adds a (positive) scale and offset so that smallest/highest value in image becomes 0 and 1 respectively.
        Operates on each channel separately


        :minimum: Minimum value after normalization

        :maximum: Maximum value after normalization




    **real**
        Gives the real valued part of a complex image





    **scale/offset**
        Adds a scale and/or an offset to each channel equally


        :scale: Scale factor applied to image before offset

        :offset: Offset applied to image after scale




    **to integer**
        Converts all channels into integer data


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)
    **k** (k)
        (no description)
    **maximum** (maximum)
        (no description)
    **minimum** (minimum)
        (no description)
    **offset** (offset)
        (no description)
    **scale** (scale)
        (no description)
    **sigma** (sigma)
        (no description)
    **sigma-x** (sigma-x)
        (no description)
    **sigma-y** (sigma-y)
        (no description)









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

.. automodule:: node_general_filters
    :noindex:

.. class:: GeneralImageFiltering
    :noindex: