Spatial convolution custom filter

Create a spatial 2D filter kernel from list or array.

This filter allows to create a custom spatial 2D filter kernel from a list or an array. In this example, the kernel shown below was used.

Usage:

  1. Start the algorithm from the Processing Toolbox panel.

  2. Select the raster to process and modify the parameterization if necessary, then click run.

    ../../../../_images/interface_airy_filter.png
  3. Processed image in comparison to the original.

    ../../../../_images/result_airy_filter.png

Parameters

Raster layer [raster]

Raster layer to be filtered.

Kernel [string]

Python code. See CustomKernel for information on different parameters.

Default:

from astropy.convolution import CustomKernel
array = [[1, 1, 1],
         [1, 1, 1],
         [1, 1, 1]]
kernel = CustomKernel(array)
Normalize kernel [boolean]

Whether to normalize the kernel to have a sum of one.

Default: False

Interpolate no data pixel [boolean]

Whether to interpolate no data pixel. Will result in renormalization of the kernel at each position ignoring pixels with no data values.

Default: True

Outputs

Output raster layer [rasterDestination]

Raster file destination.

Command-line usage

>qgis_process help enmapbox:SpatialConvolutionCustomFilter:

----------------
Arguments
----------------

raster: Raster layer
    Argument type:  raster
    Acceptable values:
            - Path to a raster layer
kernel: Kernel
    Default value:  from astropy.convolution import CustomKernel
array = [[1, 1, 1],
         [1, 1, 1],
         [1, 1, 1]]
kernel = CustomKernel(array)
    Argument type:  string
    Acceptable values:
            - String value
            - field:FIELD_NAME to use a data defined value taken from the FIELD_NAME field
            - expression:SOME EXPRESSION to use a data defined value calculated using a custom QGIS expression
normalize: Normalize kernel
    Default value:  false
    Argument type:  boolean
    Acceptable values:
            - 1 for true/yes
            - 0 for false/no
            - field:FIELD_NAME to use a data defined value taken from the FIELD_NAME field
            - expression:SOME EXPRESSION to use a data defined value calculated using a custom QGIS expression
interpolate: Interpolate no data pixel
    Default value:  true
    Argument type:  boolean
    Acceptable values:
            - 1 for true/yes
            - 0 for false/no
            - field:FIELD_NAME to use a data defined value taken from the FIELD_NAME field
            - expression:SOME EXPRESSION to use a data defined value calculated using a custom QGIS expression
outputRaster: Output raster layer
    Argument type:  rasterDestination
    Acceptable values:
            - Path for new raster layer

----------------
Outputs
----------------

outputRaster: <outputRaster>
    Output raster layer