Spectral convolution Trapezoid filter
1D Trapezoid filter.
The Trapezoid filter uses a trapezoidal weighting function. The filter assigns higher weights to values within a certain range and lower weights to pixels outside that range. It can be used to emphasize or suppress certain features in an image within a specific range of values.
Usage:
Start the algorithm from the Processing Toolbox panel.
Select the raster to process and modify the parameterization if necessary, then click run.
Processed image in comparison to the original.
Parameters
- Raster layer [raster]
Raster layer to be filtered.
- Kernel [string]
Python code. See Trapezoid1DKernel for information on different parameters.
Default:
from astropy.convolution import Trapezoid1DKernel kernel = Trapezoid1DKernel(width=3, slope=1)
- 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:SpectralConvolutionTrapezoidFilter
:
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Arguments
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raster: Raster layer
Argument type: raster
Acceptable values:
- Path to a raster layer
kernel: Kernel
Default value: from astropy.convolution import Trapezoid1DKernel
kernel = Trapezoid1DKernel(width=3, slope=1)
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
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Outputs
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outputRaster: <outputRaster>
Output raster layer