rasteranalysis.rst

Raster analysis

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Cell stack percent rank from value

Calculates the cell-wise percentrank value of a stack of rasters based on a single input value and writes them to an output raster.

At each cell location, the specified value is ranked among the respective values in the stack of all overlaid and sorted cell values from the input rasters. For values outside of the stack value distribution, the algorithm returns NoData because the value cannot be ranked among the cell values.

There are two methods for percentile calculation:

• Inclusive linear interpolation (PERCENTRANK.INC)
• Exclusive linear interpolation (PERCENTRANK.EXC)

The linear interpolation methods return the unique percent rank for different values. Both interpolation methods follow their counterpart methods implemented by LibreOffice or Microsoft Excel.

The output raster's extent and resolution is defined by a reference raster. Input raster layers that do not match the cell size of the reference raster layer will be resampled using nearest neighbor resampling. NoData values in any of the input layers will result in a NoData cell output if the "Ignore NoData values" parameter is not set. The output raster data type will always be Float32.

Percent ranking Value = 1. NoData cells (grey) are ignored.

.. seealso:: :ref:`qgiscellstackpercentile`, :ref:`qgiscellstackpercentrankfromrasterlayer`

Parameters

Basic parameters

Label	Name	Type	Description
Input layers	INPUT	[raster] [list]	Raster layers to evaluate. If multiband rasters are used in the data raster stack, the algorithm will always perform the analysis on the first band of the rasters
Method	METHOD	[enumeration] Default: 0	Method for percentile calculation: 0 --- Inclusive linear interpolation (PERCENTRANK.INC) 1 --- Exclusive linear interpolation (PERCENTRANK.EXC)
Value	VALUE	[numeric: double] Default: 10.0	Value to rank among the respective values in the stack of all overlaid and sorted cell values from the input rasters
Ignore NoData values	IGNORE_NODATA	[boolean] Default: True	If unchecked, any NoData cells in the input layers will result in a NoData cell in the output raster
Reference layer	REFERENCE_LAYER	[raster]	The reference layer for the output layer creation (extent, CRS, pixel dimensions)
Output layer	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Output NoData value	OUTPUT_NODATA_VALUE	[numeric: double] Default: -9999.0	Value to use for NoData in the output layer
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Output layer	OUTPUT	[raster]	Output raster layer containing the result
CRS authority identifier	CRS_AUTHID	[string]	The coordinate reference system of the output raster layer
Extent	EXTENT	[string]	The spatial extent of the output raster layer
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of columns in the output raster layer
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of rows in the output raster layer
Total pixel count	TOTAL_PIXEL_COUNT	[numeric: integer]	The count of pixels in the output raster layer

Python code

Algorithm ID: native:cellstackpercentrankfromvalue

Cell stack percentile

Calculates the cell-wise percentile value of a stack of rasters and writes the results to an output raster. The percentile to return is determined by the percentile input value (ranges between 0 and 1). At each cell location, the specified percentile is obtained using the respective value from the stack of all overlaid and sorted cell values of the input rasters.

There are three methods for percentile calculation:

• Nearest rank: returns the value that is nearest to the specified percentile
• Inclusive linear interpolation (PERCENTRANK.INC)
• Exclusive linear interpolation (PERCENTRANK.EXC)

The linear interpolation methods return the unique values for different percentiles. Both interpolation methods follow their counterpart methods implemented by LibreOffice or Microsoft Excel.

The output raster's extent and resolution is defined by a reference raster. Input raster layers that do not match the cell size of the reference raster layer will be resampled using nearest neighbor resampling. NoData values in any of the input layers will result in a NoData cell output if the "Ignore NoData values" parameter is not set. The output raster data type will always be Float32.

Percentile = 0.25. NoData cells (grey) are ignored.

.. seealso:: :ref:`qgiscellstackpercentile`, :ref:`qgiscellstackpercentrankfromrasterlayer`

Parameters

Basic parameters

Label	Name	Type	Description
Input layers	INPUT	[raster] [list]	Raster layers to evaluate. If multiband rasters are used in the data raster stack, the algorithm will always perform the analysis on the first band of the rasters
Method	METHOD	[enumeration] Default: 0	Method for percentile calculation: 0 --- Nearest rank: returns the value that is nearest to the specified percentile 1 --- Inclusive linear interpolation (PERCENTILE.INC) 2 --- Exclusive linear interpolation (PERCENTILE.EXC)
Percentile	VALUE	[numeric: double] Default: 0.25	Value to rank among the respective values in the stack of all overlaid and sorted cell values from the input rasters. Between 0 and 1.
Ignore NoData values	IGNORE_NODATA	[boolean] Default: True	If unchecked, any NoData cells in the input layers will result in a NoData cell in the output raster
Reference layer	REFERENCE_LAYER	[raster]	The reference layer for the output layer creation (extent, CRS, pixel dimensions)
Output layer	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Output NoData value	OUTPUT_NODATA_VALUE	[numeric: double] Default: -9999.0	Value to use for NoData in the output layer
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Output layer	OUTPUT	[raster]	Output raster layer containing the result
CRS authority identifier	CRS_AUTHID	[string]	The coordinate reference system of the output raster layer
Extent	EXTENT	[string]	The spatial extent of the output raster layer
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of columns in the output raster layer
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of rows in the output raster layer
Total pixel count	TOTAL_PIXEL_COUNT	[numeric: integer]	The count of pixels in the output raster layer

Python code

Algorithm ID: native:cellstackpercentile

Cell stack percentrank from raster layer

Calculates the cell-wise percentrank value of a stack of rasters based on an input value raster and writes them to an output raster.

At each cell location, the current value of the value raster is ranked among the respective values in the stack of all overlaid and sorted cell values of the input rasters. For values outside of the the stack value distribution, the algorithm returns NoData because the value cannot be ranked among the cell values.

There are two methods for percentile calculation:

• Inclusive linear interpolation (PERCENTRANK.INC)
• Exclusive linear interpolation (PERCENTRANK.EXC)

The linear interpolation methods return the unique values for different percentiles. Both interpolation methods follow their counterpart methods implemented by LibreOffice or Microsoft Excel.

The output raster's extent and resolution is defined by a reference raster. Input raster layers that do not match the cell size of the reference raster layer will be resampled using nearest neighbor resampling. NoData values in any of the input layers will result in a NoData cell output if the "Ignore NoData values" parameter is not set. The output raster data type will always be Float32.

Ranking the value raster layer cells. NoData cells (grey) are ignored.

.. seealso:: :ref:`qgiscellstackpercentile`, :ref:`qgiscellstackpercentrankfromvalue`

Parameters

Basic parameters

Label	Name	Type	Description
Input layers	INPUT	[raster] [list]	Raster layers to evaluate. If multiband rasters are used in the data raster stack, the algorithm will always perform the analysis on the first band of the rasters
Value raster layer	INPUT_VALUE_RASTER	[raster]	The layer to rank the values among the stack of all overlaid layers
Value raster band	VALUE_RASTER_BAND	[numeric: integer] Default: 1	Band of the "value raster layer" to compare to
Method	METHOD	[enumeration] Default: 0	Method for percentile calculation: 0 --- Inclusive linear interpolation (PERCENTRANK.INC) 1 --- Exclusive linear interpolation (PERCENTRANK.EXC)
Ignore NoData values	IGNORE_NODATA	[boolean] Default: True	If unchecked, any NoData cells in the input layers will result in a NoData cell in the output raster
Reference layer	REFERENCE_LAYER	[raster]	The reference layer for the output layer creation (extent, CRS, pixel dimensions)
Output layer	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Output NoData value	OUTPUT_NODATA_VALUE	[numeric: double] Default: -9999.0	Value to use for NoData in the output layer
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Output layer	OUTPUT	[raster]	Output raster layer containing the result
CRS authority identifier	CRS_AUTHID	[string]	The coordinate reference system of the output raster layer
Extent	EXTENT	[string]	The spatial extent of the output raster layer
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of columns in the output raster layer
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of rows in the output raster layer
Total pixel count	TOTAL_PIXEL_COUNT	[numeric: integer]	The count of pixels in the output raster layer

Python code

Algorithm ID: native:cellstackpercentrankfromrasterlayer

Cell statistics

Computes per-cell statistics based on input raster layers and for each cell writes the resulting statistics to an output raster. At each cell location, the output value is defined as a function of all overlaid cell values of the input rasters.

By default, a NoData cell in ANY of the input layers will result in a NoData cell in the output raster. If the :guilabel:`Ignore NoData values` option is checked, then NoData inputs will be ignored in the statistic calculation. This may result in NoData output for locations where all cells are NoData.

The :guilabel:`Reference layer` parameter specifies an existing raster layer to use as a reference when creating the output raster. The output raster will have the same extent, CRS, and pixel dimensions as this layer.

Calculation details: Input raster layers that do not match the cell size of the reference raster layer will be resampled using nearest neighbor resampling. The output raster data type will be set to the most complex data type present in the input datasets except when using the functions Mean, Standard deviation and Variance (data type is always Float32 or Float64 depending on input float type) or Count and Variety (data type is always Int32).

• Count: The count statistic will always result in the number of cells without NoData values at the current cell location.
• Median: If the number of input layers is even, the median will be calculated as the arithmetic mean of the two middle values of the ordered cell input values.
• Minority/Majority: If no unique minority or majority could be found, the result is NoData, except all input cell values are equal.

Example with all the statistic functions. NoData cells (grey) are taken into account.

Parameters

Basic parameters

Label	Name	Type	Description
Input layers	INPUT	[raster] [list]	Input raster layers
Statistic	STATISTIC	[enumeration] Default: 0	Available statistics. Options: 0 --- Sum 1 --- Count 2 --- Mean 3 --- Median 4 --- Standard deviation 5 --- Variance 6 --- Minimum 7 --- Maximum 8 --- Minority (least common value) 9 --- Majority (most common value) 10 --- Range (max - min) 11 --- Variety (unique value count)
Ignore NoData values	IGNORE_NODATA	[boolean] Default: True	Calculate statistics also for all cells stacks, ignoring NoData occurrence.
Reference layer	REF_LAYER	[raster]	The reference layer to create the output layer from (extent, CRS, pixel dimensions)
Output layer	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Output NoData value Optional	OUTPUT_NO_DATA_VALUE	[numeric: double] Default: -9999.0	Value to use for NoData in the output layer
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
CRS authority identifier	CRS_AUTHID	[crs]	The coordinate reference system of the output raster layer
Extent	EXTENT	[string]	The spatial extent of the output raster layer
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of rows in the output raster layer
Output raster	OUTPUT	[raster]	Output raster layer containing the result
Total pixel count	TOTAL_PIXEL_COUNT	[numeric: integer]	The count of pixels in the output raster layer
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of columns in the output raster layer

Python code

Algorithm ID: native:cellstatistics

Equal to frequency

Evaluates on a cell-by-cell basis the frequency (number of times) the values of an input stack of rasters are equal to the value of a value layer. The output raster extent and resolution are defined by the input raster layer and is always of Int32 type.

If multiband rasters are used in the data raster stack, the algorithm will always perform the analysis on the first band of the rasters - use GDAL to use other bands in the analysis. The output NoData value can be set manually.

For each cell in the output raster, the value represents the number of times that the corresponding cells in the list of rasters are the same as the value raster. NoData cells (grey) are taken into account.

.. seealso:: :ref:`qgisgreaterthanfrequency`, :ref:`qgislessthanfrequency`

Parameters

Basic parameters

Label	Name	Type	Description
Input value raster	INPUT_VALUE_RASTER	[raster]	The input value layer serves as reference layer for the sample layers
Value raster band	INPUT_VALUE_RASTER_BAND	[raster band] Default: The first band of the raster layer	Select the band you want to use as sample
Input raster layers	INPUT_RASTERS	[raster] [list]	Raster layers to evaluate. If multiband rasters are used in the data raster stack, the algorithm will always perform the analysis on the first band of the rasters
Ignore NoData values	IGNORE_NODATA	[boolean] Default: False	If unchecked, any NoData cells in the value raster or the data layer stack will result in a NoData cell in the output raster
Output layer	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Output NoData value Optional	OUTPUT_NO_DATA_VALUE	[numeric: double] Default: -9999.0	Value to use for NoData in the output layer
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Output layer	OUTPUT	[raster]	Output raster layer containing the result
CRS authority identifier	CRS_AUTHID	[string]	The coordinate reference system of the output raster layer
Extent	EXTENT	[string]	The spatial extent of the output raster layer
Count of cells with equal value occurrences	FOUND_LOCATIONS_COUNT	[numeric: integer]
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of rows in the output raster layer
Total pixel count	TOTAL_PIXEL_COUNT	[numeric: integer]	The count of pixels in the output raster layer
Mean frequency at valid cell locations	MEAN_FREQUENCY_PER_LOCATION	[numeric: double]
Count of value occurrences	OCCURRENCE_COUNT	[numeric: integer]
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of columns in the output raster layer

Python code

Algorithm ID: native:equaltofrequency

Fuzzify raster (gaussian membership)

Transforms an input raster to a fuzzified raster by assigning a membership value to each pixel, using a Gaussian membership function. Membership values range from 0 to 1. In the fuzzified raster, a value of 0 implies no membership of the defined fuzzy set, whereas a value of 1 means full membership. The gaussian membership function is defined as , where f1 is the spread and f2 the midpoint.

Fuzzify raster example. Input raster source: Land Tirol - data.tirol.gv.at.

.. seealso:: :ref:`qgisfuzzifyrasterlargemembership`,
  :ref:`qgisfuzzifyrasterlinearmembership`,
  :ref:`qgisfuzzifyrasternearmembership`,
  :ref:`qgisfuzzifyrasterpowermembership`,
  :ref:`qgisfuzzifyrastersmallmembership`

Parameters

Basic parameters

Label	Name	Type	Description
Input Raster	INPUT	[raster]	Input raster layer
Band Number	BAND	[raster band] Default: The first band of the raster layer	If the raster is multiband, choose the band that you want to fuzzify.
Function midpoint	FUZZYMIDPOINT	[numeric: double] Default: 10.0	Midpoint of the gaussian function
Function spread	FUZZYSPREAD	[numeric: double] Default: 0.01	Spread of the gaussian function
Fuzzified raster	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Fuzzified raster	OUTPUT	[raster]	Output raster layer containing the result
CRS authority identifier	CRS_AUTHID	[crs]	The coordinate reference system of the output raster layer
Extent	EXTENT	[string]	The spatial extent of the output raster layer
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of columns in the output raster layer
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of rows in the output raster layer
Total pixel count	TOTAL_PIXEL_COUNT	[numeric: integer]	The count of pixels in the output raster layer

Python code

Algorithm ID: native:fuzzifyrastergaussianmembership

Fuzzify raster (large membership)

Transforms an input raster to a fuzzified raster by assigning a membership value to each pixel, using a Large membership function. Membership values range from 0 to 1. In the fuzzified raster, a value of 0 implies no membership of the defined fuzzy set, whereas a value of 1 means full membership. The large membership function is defined as , where f1 is the spread and f2 the midpoint.

.. seealso:: :ref:`qgisfuzzifyrastergaussianmembership`,
  :ref:`qgisfuzzifyrasterlinearmembership`,
  :ref:`qgisfuzzifyrasternearmembership`,
  :ref:`qgisfuzzifyrasterpowermembership`,
  :ref:`qgisfuzzifyrastersmallmembership`

Parameters

Basic parameters

Label	Name	Type	Description
Input Raster	INPUT	[raster]	Input raster layer
Band Number	BAND	[raster band] Default: The first band of the raster layer	If the raster is multiband, choose the band that you want to fuzzify.
Function midpoint	FUZZYMIDPOINT	[numeric: double] Default: 50.0	Midpoint of the large function
Function spread	FUZZYSPREAD	[numeric: double] Default: 5.0	Spread of the large function
Fuzzified raster	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Fuzzified raster	OUTPUT	[raster]	Output raster layer containing the result
CRS authority identifier	CRS_AUTHID	[crs]	The coordinate reference system of the output raster layer
Extent	EXTENT	[string]	The spatial extent of the output raster layer
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of columns in the output raster layer
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of rows in the output raster layer
Total pixel count	TOTAL_PIXEL_COUNT	[numeric: integer]	The count of pixels in the output raster layer

Python code

Algorithm ID: native:fuzzifyrasterlargemembership

Fuzzify raster (linear membership)

Transforms an input raster to a fuzzified raster by assigning a membership value to each pixel, using a Linear membership function. Membership values range from 0 to 1. In the fuzzified raster, a value of 0 implies no membership of the defined fuzzy set, whereas a value of 1 means full membership. The linear function is defined as , where a is the low bound and b the high bound. This equation assigns membership values using a linear transformation for pixel values between the low and high bounds. Pixels values smaller than the low bound are given 0 membership whereas pixel values greater than the high bound are given 1 membership.

.. seealso:: :ref:`qgisfuzzifyrastergaussianmembership`,
  :ref:`qgisfuzzifyrasterlargemembership`,
  :ref:`qgisfuzzifyrasternearmembership`,
  :ref:`qgisfuzzifyrasterpowermembership`,
  :ref:`qgisfuzzifyrastersmallmembership`

Parameters

Basic parameters

Label	Name	Type	Description
Input Raster	INPUT	[raster]	Input raster layer
Band Number	BAND	[raster band] Default: The first band of the raster layer	If the raster is multiband, choose the band that you want to fuzzify.
Low fuzzy membership bound	FUZZYLOWBOUND	[numeric: double] Default: 0.0	Low bound of the linear function
High fuzzy membership bound	FUZZYHIGHBOUND	[numeric: double] Default: 1.0	High bound of the linear function
Fuzzified raster	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Fuzzified raster	OUTPUT	[raster]	Output raster layer containing the result
CRS authority identifier	CRS_AUTHID	[crs]	The coordinate reference system of the output raster layer
Extent	EXTENT	[string]	The spatial extent of the output raster layer
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of columns in the output raster layer
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of rows in the output raster layer
Total pixel count	TOTAL_PIXEL_COUNT	[numeric: integer]	The count of pixels in the output raster layer

Python code

Algorithm ID: native:fuzzifyrasterlinearmembership

Fuzzify raster (near membership)

Transforms an input raster to a fuzzified raster by assigning a membership value to each pixel, using a Near membership function. Membership values range from 0 to 1. In the fuzzified raster, a value of 0 implies no membership of the defined fuzzy set, whereas a value of 1 means full membership. The near membership function is defined as , where f1 is the spread and f2 the midpoint.

.. seealso:: :ref:`qgisfuzzifyrastergaussianmembership`,
  :ref:`qgisfuzzifyrasterlargemembership`,
  :ref:`qgisfuzzifyrasterlinearmembership`,
  :ref:`qgisfuzzifyrasterpowermembership`,
  :ref:`qgisfuzzifyrastersmallmembership`

Parameters

Basic parameters

Label	Name	Type	Description
Input Raster	INPUT	[raster]	Input raster layer
Band Number	BAND	[raster band] Default: The first band of the raster layer	If the raster is multiband, choose the band that you want to fuzzify.
Function midpoint	FUZZYMIDPOINT	[numeric: double] Default: 50.0	Midpoint of the near function
Function spread	FUZZYSPREAD	[numeric: double] Default: 0.01	Spread of the near function
Fuzzified raster	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Fuzzified raster	OUTPUT	[raster]	Output raster layer containing the result
CRS authority identifier	CRS_AUTHID	[crs]	The coordinate reference system of the output raster layer
Extent	EXTENT	[string]	The spatial extent of the output raster layer
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of columns in the output raster layer
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of rows in the output raster layer
Total pixel count	TOTAL_PIXEL_COUNT	[numeric: integer]	The count of pixels in the output raster layer

Python code

Algorithm ID: native:fuzzifyrasternearmembership

Fuzzify raster (power membership)

Transforms an input raster to a fuzzified raster by assigning a membership value to each pixel, using a Power membership function. Membership values range from 0 to 1. In the fuzzified raster, a value of 0 implies no membership of the defined fuzzy set, whereas a value of 1 means full membership. The power function is defined as , where a is the low bound, b is the high bound, and f1 the exponent. This equation assigns membership values using the power transformation for pixel values between the low and high bounds. Pixels values smaller than the low bound are given 0 membership whereas pixel values greater than the high bound are given 1 membership.

.. seealso:: :ref:`qgisfuzzifyrastergaussianmembership`, :ref:`qgisfuzzifyrasterlargemembership`,
  :ref:`qgisfuzzifyrasterlinearmembership`, :ref:`qgisfuzzifyrasternearmembership`,
  :ref:`qgisfuzzifyrastersmallmembership`

Parameters

Basic parameters

Label	Name	Type	Description
Input Raster	INPUT	[raster]	Input raster layer
Band Number	BAND	[raster band] Default: The first band of the raster layer	If the raster is multiband, choose the band that you want to fuzzify.
Low fuzzy membership bound	FUZZYLOWBOUND	[numeric: double] Default: 0.0	Low bound of the power function
High fuzzy membership bound	FUZZYHIGHBOUND	[numeric: double] Default: 1.0	High bound of the power function
High fuzzy membership bound	FUZZYEXPONENT	[numeric: double] Default: 2.0	Exponent of the power function
Fuzzified raster	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Fuzzified raster	OUTPUT	[raster]	Output raster layer containing the result
CRS authority identifier	CRS_AUTHID	[crs]	The coordinate reference system of the output raster layer
Extent	EXTENT	[string]	The spatial extent of the output raster layer
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of columns in the output raster layer
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of rows in the output raster layer
Total pixel count	TOTAL_PIXEL_COUNT	[numeric: integer]	The count of pixels in the output raster layer

Python code

Algorithm ID: native:fuzzifyrasterpowermembership

Fuzzify raster (small membership)

Transforms an input raster to a fuzzified raster by assigning a membership value to each pixel, using a Small membership function. Membership values range from 0 to 1. In the fuzzified raster, a value of 0 implies no membership of the defined fuzzy set, whereas a value of 1 means full membership. The small membership function is defined as , where f1 is the spread and f2 the midpoint.

.. seealso:: :ref:`qgisfuzzifyrastergaussianmembership`,
  :ref:`qgisfuzzifyrasterlargemembership`
  :ref:`qgisfuzzifyrasterlinearmembership`,
  :ref:`qgisfuzzifyrasternearmembership`,
  :ref:`qgisfuzzifyrasterpowermembership`

Parameters

Basic parameters

Label	Name	Type	Description
Input Raster	INPUT	[raster]	Input raster layer
Band Number	BAND	[raster band] Default: The first band of the raster layer	If the raster is multiband, choose the band that you want to fuzzify.
Function midpoint	FUZZYMIDPOINT	[numeric: double] Default: 50.0	Midpoint of the small function
Function spread	FUZZYSPREAD	[numeric: double] Default: 5.0	Spread of the small function
Fuzzified raster	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Fuzzified raster	OUTPUT	[raster]	Output raster layer containing the result
CRS authority identifier	CRS_AUTHID	[crs]	The coordinate reference system of the output raster layer
Extent	EXTENT	[string]	The spatial extent of the output raster layer
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of columns in the output raster layer
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of rows in the output raster layer
Total pixel count	TOTAL_PIXEL_COUNT	[numeric: integer]	The count of pixels in the output raster layer

Python code

Algorithm ID: native:fuzzifyrastersmallmembership

Gaussian blur

Applies a Gaussian blur filter to an input raster layer. The radius parameter controls the strength of the blur. A larger radius results in a smoother output, at the cost of execution time.

Parameters

Basic parameters

Label	Name	Type	Description
Input layer	INPUT	[raster]	Input raster layer to be processed.
Band number	BAND	[raster band] Default: The first band of the raster layer	If the raster is multiband, choose the band that you want to process.
Blur radius (pixels)	RADIUS	[numeric: integer] Default: 2	The radius of the Gaussian kernel in pixels. Larger values produce a more pronounced blur effect.
Output layer	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster containing the result. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Creation options Optional	CREATION_OPTIONS	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Output layer	OUTPUT	[raster]	Output raster layer containing the result.

Python code

Algorithm ID: native:rastergaussianblur

Greater than frequency

Evaluates on a cell-by-cell basis the frequency (number of times) the values of an input stack of rasters are equal to the value of a value raster. The output raster extent and resolution is defined by the input raster layer and is always of Int32 type.

If multiband rasters are used in the data raster stack, the algorithm will always perform the analysis on the first band of the rasters - use GDAL to use other bands in the analysis. The output NoData value can be set manually.

For each cell in the output raster, the value represents the number of times that the corresponding cells in the list of rasters are greater than the value raster. NoData cells (grey) are taken into account.

.. seealso:: :ref:`qgisequaltofrequency`, :ref:`qgislessthanfrequency`

Python code

Algorithm ID: native:greaterthanfrequency

Highest position in raster stack

Evaluates on a cell-by-cell basis the position of the raster with the highest value in a stack of rasters. Position counts start with 1 and range to the total number of input rasters. The order of the input rasters is relevant for the algorithm. If multiple rasters feature the highest value, the first raster will be used for the position value.

If multiband rasters are used in the data raster stack, the algorithm will always perform the analysis on the first band of the rasters - use GDAL to use other bands in the analysis. Any NoData cells in the raster layer stack will result in a NoData cell in the output raster unless the "ignore NoData" parameter is checked. The output NoData value can be set manually. The output rasters extent and resolution is defined by a reference raster layer and is always of Int32 type.

.. seealso:: :ref:`qgislowestpositioninrasterstack`

Parameters

Basic parameters

Label	Name	Type	Description
Input raster layers	INPUT_RASTERS	[raster] [list]	List of raster layers to compare with
Reference layer	REFERENCE_LAYER	[raster]	The reference layer for the output layer creation (extent, CRS, pixel dimensions)
Ignore NoData values	IGNORE_NODATA	[boolean] Default: False	If unchecked, any NoData cells in the data layer stack will result in a NoData cell in the output raster
Output layer	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster containing the result. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Output NoData value	OUTPUT_NODATA_VALUE	[numeric: double] Default: -9999.0	Value to use for NoData in the output layer
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Output layer	OUTPUT	[raster]	Output raster layer containing the result
CRS authority identifier	CRS_AUTHID	[string]	The coordinate reference system of the output raster layer
Extent	EXTENT	[string]	The spatial extent of the output raster layer
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of columns in the output raster layer
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of rows in the output raster layer
Total pixel count	TOTAL_PIXEL_COUNT	[numeric: integer]	The count of pixels in the output raster layer

Python code

Algorithm ID: native:highestpositioninrasterstack

Less than frequency

Evaluates on a cell-by-cell basis the frequency (number of times) the values of an input stack of rasters are less than the value of a value raster. The output raster extent and resolution is defined by the input raster layer and is always of Int32 type.

If multiband rasters are used in the data raster stack, the algorithm will always perform the analysis on the first band of the rasters - use GDAL to use other bands in the analysis. The output NoData value can be set manually.

For each cell in the output raster, the value represents the number of times that the corresponding cells in the list of rasters are less than the value raster. NoData cells (grey) are taken into account.

.. seealso:: :ref:`qgisequaltofrequency`, :ref:`qgisgreaterthanfrequency`

Python code

Algorithm ID: native:lessthanfrequency

Lowest position in raster stack

Evaluates on a cell-by-cell basis the position of the raster with the lowest value in a stack of rasters. Position counts start with 1 and range to the total number of input rasters. The order of the input rasters is relevant for the algorithm. If multiple rasters feature the lowest value, the first raster will be used for the position value.

If multiband rasters are used in the data raster stack, the algorithm will always perform the analysis on the first band of the rasters - use GDAL to use other bands in the analysis. Any NoData cells in the raster layer stack will result in a NoData cell in the output raster unless the "ignore NoData" parameter is checked. The output NoData value can be set manually. The output rasters extent and resolution is defined by a reference raster layer and is always of Int32 type.

.. seealso:: :ref:`qgishighestpositioninrasterstack`

Python code

Algorithm ID: native:lowestpositioninrasterstack

Raster boolean AND

Calculates the boolean AND for a set of input rasters. If all of the input rasters have a non-zero value for a pixel, that pixel will be set to 1 in the output raster. If any of the input rasters have 0 values for the pixel it will be set to 0 in the output raster.

The reference layer parameter specifies an existing raster layer to use as a reference when creating the output raster. The output raster will have the same extent, CRS, and pixel dimensions as this layer.

By default, a NoData pixel in ANY of the input layers will result in a NoData pixel in the output raster. If the :guilabel:`Treat NoData values as false` option is checked, then NoData inputs will be treated the same as a 0 input value.

.. seealso:: :ref:`qgisrasterbooleanor`

Parameters

Basic parameters

Label	Name	Type	Description
Input layers	INPUT	[raster] [list]	List of input raster layers
Reference layer	REF_LAYER	[raster]	The reference layer to create the output layer from (extent, CRS, pixel dimensions)
Treat NoData values as false	NODATA_AS_FALSE	[boolean] Default: False	Treat NoData values in the input files as 0 when performing the operation
Output layer	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster containing the result. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Output NoData value	NO_DATA	[numeric: double] Default: -9999.0	Value to use for NoData in the output layer
Output data type	DATA_TYPE	[enumeration] Default: 5	Output raster data type. Options:
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Extent	EXTENT	[string]	The spatial extent of the output raster layer
CRS authority identifier	CRS_AUTHID	[crs]	The coordinate reference system of the output raster layer
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of columns in the output raster layer
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of rows in the output raster layer
Total pixel count	TOTAL_PIXEL_COUNT	[numeric: integer]	The count of pixels in the output raster layer
NoData pixel count	NODATA_PIXEL_COUNT	[numeric: integer]	The count of NoData pixels in the output raster layer
True pixel count	TRUE_PIXEL_COUNT	[numeric: integer]	The count of True pixels (value = 1) in the output raster layer
False pixel count	FALSE_PIXEL_COUNT	[numeric: integer]	The count of False pixels (value = 0) in the output raster layer
Output layer	OUTPUT	[raster]	Output raster layer containing the result

Python code

Algorithm ID: native:rasterbooleanand

Raster boolean OR

Calculates the boolean OR for a set of input rasters. If all of the input rasters have a zero value for a pixel, that pixel will be set to 0 in the output raster. If any of the input rasters have 1 values for the pixel it will be set to 1 in the output raster.

The reference layer parameter specifies an existing raster layer to use as a reference when creating the output raster. The output raster will have the same extent, CRS, and pixel dimensions as this layer.

By default, a NoData pixel in ANY of the input layers will result in a NoData pixel in the output raster. If the :guilabel:`Treat NoData values as false` option is checked, then NoData inputs will be treated the same as a 0 input value.

.. seealso:: :ref:`qgisrasterbooleanand`

Parameters

Basic parameters

Label	Name	Type	Description
Input layers	INPUT	[raster] [list]	List of input raster layers
Reference layer	REF_LAYER	[raster]	The reference layer to create the output layer from (extent, CRS, pixel dimensions)
Treat NoData values as false	NODATA_AS_FALSE	[boolean] Default: False	Treat NoData values in the input files as 0 when performing the operation
Output layer	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster containing the result. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Output NoData value	NO_DATA	[numeric: double] Default: -9999.0	Value to use for NoData in the output layer
Output data type	DATA_TYPE	[enumeration] Default: 5	Output raster data type. Options:
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Extent	EXTENT	[string]	The spatial extent of the output raster layer
CRS authority identifier	CRS_AUTHID	[crs]	The coordinate reference system of the output raster layer
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of columns in the output raster layer
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of rows in the output raster layer
Total pixel count	TOTAL_PIXEL_COUNT	[numeric: integer]	The count of pixels in the output raster layer
NoData pixel count	NODATA_PIXEL_COUNT	[numeric: integer]	The count of NoData pixels in the output raster layer
True pixel count	TRUE_PIXEL_COUNT	[numeric: integer]	The count of True pixels (value = 1) in the output raster layer
False pixel count	FALSE_PIXEL_COUNT	[numeric: integer]	The count of False pixels (value = 0) in the output raster layer
Output layer	OUTPUT	[raster]	Output raster layer containing the result

Python code

Algorithm ID: native:rasterbooleanor

Raster calculator

Performs algebraic operations using raster layers.

The resulting layer will have its values computed according to an expression. The expression can contain numerical values, operators and references to any of the layers in the current project.

.. seealso:: :ref:`qgisvirtualrastercalc`, :ref:`gdalrastercalculator`, :ref:`label_raster_calc`

Parameters

Basic parameters

Label	Name	Type	Description
Input layers	INPUT	[raster] [list]	List of input raster layers
Expression	EXPRESSION	[expression]	:ref:`Raster-based expression <raster_expression>` that will be used to calculate the output raster layer.
Output extent Optional	EXTENT	[extent]	Specify the spatial extent of the output raster layer. If the extent is not specified, the minimum extent that covers all the selected reference layers will be used.
Output cell size (leave empty to set automatically) Optional	CELLSIZE	[numeric: double]	Cell size of the output raster layer. If the cell size is not specified, the minimum cell size of the selected reference layer(s) will be used. The cell size will be the same for the X and Y axes.
Output CRS Optional	CRS	[crs]	CRS of the output raster layer. If the output CRS is not specified, the CRS of the first reference layer will be used.
Calculated	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Creation options Optional	CREATION_OPTIONS	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Calculated	OUTPUT	[raster]	Output raster file with the calculated values.

Python code

Algorithm ID: native:rastercalc

Raster calculator (virtual)

Performs algebraic operations using raster layers and generates in-memory result.

The resulting layer will have its values computed according to an expression. The expression can contain numerical values, operators and references to any of the layers in the current project.

A virtual raster layer is a raster layer defined by its URI and whose pixels are calculated on-the-fly. It's not a new file on disk; the virtual layer is still connected to the rasters used in the calculation meaning that deleting or moving these rasters would break it. A :guilabel:`Layer name` can be provided, otherwise the calculation expression is used as such. Removing the virtual layer from the project deletes it, and it can be made persistent in file using the layer :menuselection:`Export --> Save as...` contextual menu.

.. seealso:: :ref:`qgisrastercalc`, :ref:`gdalrastercalculator`, :ref:`label_raster_calc`

Parameters

Label	Name	Type	Description
Input layers	INPUT	[raster] [list]	List of input raster layers
Expression	EXPRESSION	[expression]	:ref:`Raster-based expression <raster_expression>` that will be used to calculate the output raster layer.
Output extent Optional	EXTENT	[extent]	Specify the spatial extent of the output raster layer. If the extent is not specified, the minimum extent that covers all the selected reference layers will be used.
Output cell size (leave empty to set automatically) Optional	CELLSIZE	[numeric: double]	Cell size of the output raster layer. If the cell size is not specified, the minimum cell size of the selected reference layer(s) will be used. The cell size will be the same for the X and Y axes.
Output CRS Optional	CRS	[crs]	CRS of the output raster layer. If the output CRS is not specified, the CRS of the first reference layer will be used.
Output layer name Optional	LAYER_NAME	[string]	The name to assign to the generated layer. If not set, the text of the calculation expression is used.

Outputs

Label	Name	Type	Description
Calculated	OUTPUT	[raster]	Output virtual raster layer with the calculated values.

Python code

Algorithm ID: native:virtualrastercalc

Raster layer properties

Returns basic properties of the given raster layer, including the extent, size in pixels and dimensions of pixels (in map units), number of bands, and NoData value.

This algorithm is intended for use as a means of extracting these useful properties to use as the input values to other algorithms in a model - e.g. to allow to pass an existing raster's pixel sizes over to a GDAL raster algorithm.

Parameters

Label	Name	Type	Description
Input layer	INPUT	[raster]	Input raster layer
Band number Optional	BAND	[raster band] Default: Not set	Whether to also return properties of a specific band. If a band is specified, the noData value for the selected band is also returned.

Outputs

Label	Name	Type	Description
Number of bands in raster	BAND_COUNT	[numeric: integer]	The number of bands in the raster
CRS authority identifier	CRS_AUTHID	[string]	The coordinate reference system of the output raster layer
Extent	EXTENT	[string]	The raster layer extent in the CRS
Band has a NoData value set	HAS_NODATA_VALUE	[Boolean]	Indicates whether the raster layer has a value set for NoData pixels in the selected band
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of columns in the raster layer
Band NoData value	NODATA_VALUE	[numeric: double]	The value (if set) of the NoData pixels in the selected band
Pixel size (height) in map units	PIXEL_HEIGHT	[numeric: integer]	Vertical size in map units of the pixel
Pixel size (width) in map units	PIXEL_WIDTH	[numeric: integer]	Horizontal size in map units of the pixel
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of rows in the raster layer
Maximum x-coordinate	X_MAX	[numeric: double]
Minimum x-coordinate	X_MIN	[numeric: double]
Maximum y-coordinate	Y_MAX	[numeric: double]
Minimum y-coordinate	Y_MIN	[numeric: double]

Python code

Algorithm ID: native:rasterlayerproperties

Raster layer statistics

Calculates basic statistics from the values in a given band of the raster layer. The output is loaded in the :menuselection:`Processing --> Results viewer` menu.

Parameters

Label	Name	Type	Description
Input layer	INPUT	[raster]	Input raster layer
Band number	BAND	[raster band] Default: The first band of the input layer	If the raster is multiband, choose the band you want to get statistics for.
Statistics	OUTPUT_HTML_FILE	[html] Default: [Save to temporary file]	Specification of the output file:

Outputs

Label	Name	Type	Description
Maximum value	MAX	[numeric: double]
Mean value	MEAN	[numeric: double]
Minimum value	MIN	[numeric: double]
Statistics	OUTPUT_HTML_FILE	[html]	The output file contains the following information: Analyzed file: path of the raster layer Minimum value: minimum value of the raster Maximum value: maximum value of the raster Range: difference between the maximum and minimum values Sum: total sum of the values Mean value: mean of the values Standard deviation: standard deviation of the values Sum of the squares: sum of the squared differences of each observation from the overall mean
Range	RANGE	[numeric: double]
Standard deviation	STD_DEV	[numeric: double]
Sum	SUM	[numeric: double]
Sum of the squares	SUM_OF_SQUARES	[numeric: double]

Python code

Algorithm ID: native:rasterlayerstatistics

Raster layer unique values report

Returns the count and area of each unique value in a given raster layer. The calculation of the area is done in the area unit of the layer's CRS.

Parameters

Label	Name	Type	Description
Input layer	INPUT	[raster]	Input raster layer
Band number	BAND	[raster band] Default: The first band of the input layer	If the raster is multiband, choose the band you want to get statistics for.
Unique values report	OUTPUT_HTML_FILE	[file] Default: [Save to temporary file]	Specification of the output file:
Unique values table	OUTPUT_TABLE	[vector: table] Default: [Skip output]	Specification of the table for unique values:

Outputs

Label	Name	Type	Description
CRS authority identifier	CRS_AUTHID	[string]	The coordinate reference system of the output raster layer
Extent	EXTENT	[string]	The spatial extent of the output raster layer
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of rows in the output raster layer
NoData pixel count	NODATA_PIXEL_COUNT	[numeric: integer]	The number of NoData pixels in the output raster layer
Total pixel count	TOTAL_PIXEL_COUNT	[numeric: integer]	The count of pixels in the output raster layer
Unique values report	OUTPUT_HTML_FILE	[html]	The output HTML file contains the following information: Analyzed file: the path of the raster layer Extent: xmin, ymin, xmax, ymax coordinates of the extent Projection: projection of the layer Width in pixels: number of columns and pixel width size Height in pixels: number of rows and pixel width size Total pixel count: count of all the pixels NoData pixel count: count of pixels with NoData value
Unique values table	OUTPUT_TABLE	[vector: table]	A table with three columns: value: pixel value count: count of pixels with this value m2 or deg2 or ft2 or ... : total area of pixels with this value. The column name depends on the area unit of the layer's CRS and the calculation is done in that unit.
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of columns in the output raster layer

Python code

Algorithm ID: native:rasterlayeruniquevaluesreport

Raster layer zonal statistics

Calculates statistics for a raster layer's values, categorized by zones defined in another raster layer.

.. seealso:: :ref:`qgiszonalstatisticsfb`

Parameters

Basic parameters

Label	Name	Type	Description
Input Layer	INPUT	[raster]	Input raster layer
Band number	BAND	[raster band] Default: The first band of the raster layer	If the raster is multiband choose the band for which you want to calculate the statistics.
Zones layer	ZONES	[raster]	Raster layer defining zones. Zones are given by contiguous pixels having the same pixel value.
Zones band number	ZONES_BAND	[raster band] Default: The first band of the raster layer	If the raster is multiband, choose the band that defines the zones
Statistics	OUTPUT_TABLE	[vector: table] Default: [Create temporary layer]	Specification of the output report. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Reference layer Optional	REF_LAYER	[enumeration] Default: 0	Raster layer used to calculate the centroids that will be used as reference when determining the zones in the output layer. One of: 0 --- Input layer: zones are determined by sampling the zone raster layer value at the centroid of each pixel from the source raster layer 1 --- Zones layer: the input raster layer will be sampled at the centroid of each pixel from the zones raster layer

Outputs

Label	Name	Type	Description
CRS authority identifier	CRS_AUTHID	[string]	The coordinate reference system of the output raster layer
Extent	EXTENT	[string]	The spatial extent of the output raster layer
Height in pixels	HEIGHT_IN_PIXELS	[numeric: integer]	The number of rows in the output raster layer
NoData pixel count	NODATA_PIXEL_COUNT	[numeric: integer]	The number of NoData pixels in the output raster layer
Statistics	OUTPUT_TABLE	[vector: table]	The output layer contains the following information for each zone: Area: the area in square raster units in the zone; Sum: the total sum of the pixel values in the zone; Count: the number of pixels in the zone; Min: the minimum pixel value in the zone; Max: the maximum pixel value in the zone; Mean: the mean of the pixel values in the zone;
Total pixel count	TOTAL_PIXEL_COUNT	[numeric: integer]	The count of pixels in the output raster layer
Width in pixels	WIDTH_IN_PIXELS	[numeric: integer]	The number of columns in the output raster layer

Python code

Algorithm ID: native:rasterlayerzonalstats

Raster minimum/maximum

Extracts the minimum and maximum pixel values from a specified band of a raster layer. If multiple pixels share the same minimum or maximum value, only one of them will be included in the output.

Parameters

Label	Name	Type	Description
Input layer	INPUT	[raster]	Raster layer from which to extract the minimum and maximum pixel values.
Band number	BAND	[raster band] Default: 1	The band of the raster to analyze. If the raster is multiband, specify the band number (starting from 1).
Extract	EXTREMA	[enumeration] Default: 0 (Minimum and Maximum)	Choose which extrema to extract: 0: Minimum and Maximum 1: Minimum only 2: Maximum only
Output layer	OUTPUT	[vector: point] Default: [Create temporary layer]	Specification of the output layer. :ref:`One of <output_parameter_widget>`:

Outputs

Label	Name	Type	Description
Output layer	OUTPUT	[vector: point]	Vector layer with point features at the locations of the minimum and/or maximum pixel values.

Python code

Algorithm ID: native:rasterminmax

Raster rank

NEW in 3.44

Performs a cell-by-cell analysis in which output values match the rank of a sorted list of overlapping cell values from input layers. The output raster will be multi-band if multiple ranks are provided. If multiband rasters are used in the data raster stack, the algorithm will always perform the analysis on the first band of the rasters.

Raster rank result for rank 1 (minimum value). NoData cells in any input raster result in a NoData output cell.

.. seealso:: :ref:`qgiscellstackpercentrankfromvalue`, :ref:`qgiscellstackpercentile`, :ref:`qgiscellstackpercentrankfromrasterlayer`, :ref:`qgiscellstatistics`, :ref:`qgisrastercalc`

Parameters

Basic parameters

Label	Name	Type	Description
Input layer	INPUT_RASTERS	[raster] [list]	Input raster layer(s) to calculate the rank from.
Rank	RANKS	[numeric: integer] [list] Default: [1]	List of ranks to calculate for each pixel in the sorted list of cells values from the input rasters. Cells whose values match the given rank(s) are kept in the output layer. The ranks are 1-based, meaning that the first rank is 1. Negative values are also supported.
NoData value handling	NODATA_HANDLING	[enumeration] Default: 0	Choose how to handle NoData values in the input raster: 0 --- Exclude NoData from values lists: will not include NoData values in the list of pixel values when calculating ranks. 1 --- Presence of NoData in a values list results in NoData output cells: the output raster will have NoData values in the corresponding locations.
Ranked	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster containing the rank values. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Output extent Optional	EXTENT	[extent]	Specify the spatial extent of the output raster layer. If the extent is not specified, the minimum extent that covers all the selected reference layers will be used.
Output cell size Optional	CELL_SIZE	[numeric: double]	Cell size of the output raster layer. If the cell size is not specified, the minimum cell size of the selected reference layer(s) will be used. The cell size will be the same for the X and Y axes.
Output CRS Optional	CRS	[crs]	CRS of the output raster layer. If the output CRS is not specified, the CRS of the first reference layer will be used.

Outputs

Label	Name	Type	Description
Ranked	OUTPUT	[raster]	Output raster layer containing the result.

Python code

Algorithm ID: native:rasterrank

Raster surface volume

Calculates the volume under a raster surface relative to a given base level. This is mainly useful for Digital Elevation Models (DEM).

Parameters

Label	Name	Type	Description
INPUT layer	INPUT	[raster]	Input raster, representing a surface
Band number	BAND	[raster band] Default: The first band of the raster layer	If the raster is multiband, choose the band that shall define the surface.
Base level	LEVEL	[numeric: double] Default: 0.0	Define a base or reference value. This base is used in the volume calculation according to the Method parameter (see below).
Method	METHOD	[enumeration] Default: 0	Define the method for the volume calculation given by the difference between the raster pixel value and the Base level. Options: 0 --- Count Only Above Base Level: only pixels above the base level will add to the volume. 1 --- Count Only Below Base Level: only pixels below the base level will add to the volume. 2 --- Subtract Volumes Below Base level: pixels above the base level will add to the volume, pixels below the base level will subtract from the volume. 3 --- Add Volumes Below Base level: Add the volume regardless whether the pixel is above or below the base level. This is equivalent to sum the absolute values of the difference between the pixel value and the base level.
Surface volume report	OUTPUT_HTML_FILE	[html] Default: [Save to temporary file]	Specification of the output HTML report. :ref:`One of <output_parameter_widget>`:
Surface volume table	OUTPUT_TABLE	[vector: table] Default: [Skip output]	Specification of the output table. :ref:`One of <output_parameter_widget>`:

Outputs

Label	Name	Type	Description
Volume	VOLUME	[numeric: double]	The calculated volume
Area	AREA	[numeric: double]	The area in square map units
Pixel_count	PIXEL_COUNT	[numeric: integer]	The total number of pixels that have been analyzed
Surface volume report	OUTPUT_HTML_FILE	[html]	The output report (containing volume, area and pixel count) in HTML format
Surface volume table	OUTPUT_TABLE	[vector: table]	The output table (containing volume, area and pixel count)

Python code

Algorithm ID: native:rastersurfacevolume

Reclassify by layer

Reclassifies a raster band by assigning new class values based on the ranges specified in a vector table.

Parameters

Basic parameters

Label	Name	Type	Description
Raster layer	INPUT_RASTER	[raster]	Raster layer to reclassify
Band number	RASTER_BAND	[raster band] Default: The first band of the raster layer	If the raster is multiband, choose the band you want to reclassify.
Layer containing class breaks	INPUT_TABLE	[vector: any]	Vector layer containing the values to use for classification.
Minimum class value field	MIN_FIELD	[tablefield: numeric]	Field with the minimum value of the range for the class. Use -inf to capture the lowest possible value.
Maximum class value field	MAX_FIELD	[tablefield: numeric]	Field with the maximum value of the range for the class. Use inf to capture the highest possible value.
Output value field	VALUE_FIELD	[tablefield: numeric]	Field with the value that will be assigned to the pixels that fall in the class (between the corresponding min and max values). Use nan to set the value of the range to NoData.
Reclassified raster	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Output NoData value	NO_DATA	[numeric: double] Default: -9999.0	Value to apply to NoData values.
Range boundaries	RANGE_BOUNDARIES	[enumeration] Default: 0	Defines comparison rules for the classification. Options: 0 --- min < value <= max 1 --- min <= value < max 2 --- min <= value <= max 3 --- min < value < max
Use NoData when no range matches value	NODATA_FOR_MISSING	[boolean] Default: False	Applies the NoData value to band values that do not fall in any class. If False, the original value is kept.
Output data type	DATA_TYPE	[enumeration] Default: 5	Defines the format of the output raster file. Options:
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Reclassified raster	OUTPUT	[raster]	Output raster layer with reclassified band values

Python code

Algorithm ID: native:reclassifybylayer

Reclassify by table

Reclassifies a raster band by assigning new class values based on the ranges specified in a fixed table.

Parameters

Basic parameters

Label	Name	Type	Description
Raster layer	INPUT_RASTER	[raster]	Raster layer to reclassify
Band number	RASTER_BAND	[raster band] Default: 1	Raster band for which you want to recalculate values.
Reclassification table	TABLE	[vector: table]	A 3-columns table to fill with the values to set the boundaries of each class (Minimum and Maximum) and the new Value to assign to the band values that fall in the class. The value -inf can be used as minimum, inf as maximum, and nan can be used to set the output value to NoData.
Reclassified raster	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster layer. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Output NoData value	NO_DATA	[numeric: double] Default: -9999.0	Value to apply to NoData values.
Range boundaries	RANGE_BOUNDARIES	[enumeration] Default: 0	Defines comparison rules for the classification. Options: 0 --- min < value <= max 1 --- min <= value < max 2 --- min <= value <= max 3 --- min < value < max
Use NoData when no range matches value	NODATA_FOR_MISSING	[boolean] Default: False	Applies the NoData value to band values that do not fall in any class. If False, the original value is kept.
Output data type	DATA_TYPE	[enumeration] Default: 5	Defines the format of the output raster file. Options:
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Reclassified raster	OUTPUT	[raster]	Output raster layer with reclassified band values

Python code

Algorithm ID: native:reclassifybytable

Rescale raster

Rescales raster layer to a new value range, while preserving the shape (distribution) of the raster's histogram (pixel values). Input values are mapped using a linear interpolation from the source raster's minimum and maximum pixel values to the destination minimum and maximum pixel range.

By default the algorithm preserves the original NoData value, but there is an option to override it.

Rescaling values of a raster layer from [0 - 50] to [100 - 1000]

Parameters

Basic parameters

Label	Name	Type	Description
Input Raster	INPUT	[raster]	Raster layer to use for rescaling
Band number	BAND	[raster band] Default: The first band of the input layer	If the raster is multiband, choose a band.
New minimum value	MINIMUM	[numeric: double] Default value: 0.0	Minimum pixel value to use in the rescaled layer
New maximum value	MAXIMUM	[numeric: double] Default value: 255.0	Maximum pixel value to use in the rescaled layer
New NoData value Optional	NODATA	[numeric: double] Default value: Not set	Value to assign to the NoData pixels. If unset, original NoData values are preserved.
Rescaled	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output raster layer. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Rescaled	OUTPUT	[raster]	Output raster layer with rescaled band values

Python code

Algorithm ID: native:rescaleraster

Round raster

Rounds the cell values of a raster dataset according to the specified number of decimals.

Alternatively, a negative number of decimal places may be used to round values to powers of a base n. For example, with a Base value n of 10 and Decimal places of -1, the algorithm rounds cell values to multiples of 10, -2 rounds to multiples of 100, and so on. Arbitrary base values may be chosen, the algorithm applies the same multiplicative principle. Rounding cell values to multiples of a base n may be used to generalize raster layers.

The algorithm preserves the data type of the input raster. Therefore byte/integer rasters can only be rounded to multiples of a base n, otherwise a warning is raised and the raster gets copied as byte/integer raster.

Rounding values of a raster

Parameters

Basic parameters

Label	Name	Type	Description
Input raster	INPUT	[raster]	The raster to process.
Band number	BAND	[raster band] Default: 1	The band of the raster
Rounding direction	ROUNDING_DIRECTION	[list] Default: 1	How to choose the target rounded value. Options are: 0 --- Round up 1 --- Round to nearest 2 --- Round down
Number of decimals places	DECIMAL_PLACES	[numeric: integer] Default: 2	Number of decimals places to round to. Use negative values to round cell values to a multiple of a base n
Output raster	OUTPUT	[raster] Default: [Save to temporary file]	Specification of the output file. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Base n for rounding to multiples of n	BASE_N	[numeric: integer] Default: 10	When the DECIMAL_PLACES parameter is negative, raster values are rounded to multiples of the base n value
Creation options Optional	CREATION_OPTIONS (for QGIS <= 3.42, this was CREATE_OPTIONS)	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Output raster	OUTPUT	[raster]	The output raster layer with values rounded for the selected band.

Python code

Algorithm ID: native:roundrastervalues

Sample raster values

Extracts raster values at the point locations. If the raster layer is multiband, each band is sampled.

The attribute table of the resulting layer will have as many new columns as the raster layer band count.

Parameters

Label	Name	Type	Description
Input Layer	INPUT	[vector: point]	Point vector layer to use for sampling
Raster Layer	RASTERCOPY	[raster]	Raster layer to sample at the given point locations.
Output column prefix	COLUMN_PREFIX	[string] Default: 'SAMPLE_'	Prefix for the names of the added columns.
Sampled Optional	OUTPUT	[vector: point] Default: [Create temporary layer]	Specify the output layer containing the sampled values. :ref:`One of <output_parameter_widget>`:

Outputs

Label	Name	Type	Description
Sampled	OUTPUT	[vector: point]	The output layer containing the sampled values.

Python code

Algorithm ID: native:rastersampling

Zonal histogram

Appends fields representing counts of each unique value from a raster layer contained within polygon features.

The output layer attribute table will have as many fields as the unique values of the raster layer that intersects the polygon(s).

Raster layer histogram example

Parameters

Label	Name	Type	Description
Raster layer	INPUT_RASTER	[raster]	Input raster layer.
Band number	RASTER_BAND	[raster band] Default: The first band of the input layer	If the raster is multiband, choose a band.
Vector layer containing zones	INPUT_VECTOR	[vector: polygon]	Vector polygon layer that defines the zones.
Output column prefix	COLUMN_PREFIX Optional	[string] Default: 'HISTO_'	Prefix for the output columns names.
Output zones	OUTPUT	[vector: polygon] Default: [Create temporary layer]	Specify the output vector polygon layer. :ref:`One of <output_parameter_widget>`:

Outputs

Label	Name	Type	Description
Output zones	OUTPUT	[vector: polygon]	The output vector polygon layer.

Python code

Algorithm ID: native:zonalhistogram

Zonal Minimum/Maximum Point

Extracts point features corresponding to the minimum and maximum pixel values within polygon zones.

The output will contain one point feature for the minimum and one for the maximum raster value for every individual zonal feature from a polygon layer. The created point layer will be in the same spatial reference system as the selected raster layer.

Warning

This algorithm drops existing primary keys or FID values and regenerates them in output layers.

Parameters

Label	Name	Type	Description
Input Layer	INPUT	[vector: polygon]	Polygon layer defining the zones.
Raster Layer	RASTER	[raster]	Raster layer to extract the minimum and maximum values from.
Raster Band	BAND	[raster band] Default: The first band of the raster layer	If the raster has multiple bands, select the band to process.
Zonal extrema	OUTPUT	[vector: point] Default: [Create temporary layer]	Specification of the output layer. :ref:`One of <output_parameter_widget>`:

Outputs

Label	Name	Type	Description
Zonal extrema	OUTPUT	[vector: point]	Output layer containing the minimum and maximum points for each zone.

Python code

Algorithm ID: native:zonalminmaxpoint

Zonal statistics

Calculates statistics of a raster layer for each feature of an overlapping polygon vector layer.

Parameters

Label	Name	Type	Description
Input layer	INPUT	[vector: polygon]	Vector polygon layer that contains the zones.
Raster layer	INPUT_RASTER	[raster]	Input raster layer.
Raster band	RASTER_BAND	[raster band] Default: The first band of the input layer	If the raster is multiband, choose a band for the statistics.
Output column prefix	COLUMN_PREFIX	[string] Default: '_'	Prefix for the output columns names.
Statistics to calculate	STATISTICS	[enumeration] [list] Default: [0,1,2]	List of statistical operator for the output. Options: 0 --- Count 1 --- Sum 2 --- Mean 3 --- Median 4 --- St. dev. 5 --- Minimum 6 --- Maximum 7 --- Range 8 --- Minority 9 --- Majority 10 --- Variety 11 --- Variance
Zonal Statistics	OUTPUT	[vector: polygon] Default: [Create temporary layer]	Specify the output vector polygon layer. :ref:`One of <output_parameter_widget>`:

Outputs

Label	Name	Type	Description
Zonal Statistics	OUTPUT	[vector: polygon]	The zone vector layer with added statistics.

Python code

Algorithm ID: native:zonalstatisticsfb

Feature preserving DEM smoothing

NEW in 4.0

Can be used to remove surface roughness from digital elevation model without significantly altering sharp features such as breaks-in-slope, stream banks, or terrace scarps. This makes this algorithm superior to standard low-pass filters (e.g., mean, median, Gaussian) or resampling, which often blur distinct topographic features.

The algorithm works in three steps:

1. Calculating surface normal 3D vectors for each grid cell.
2. Smoothing the normal vector field using a filter that applies more weight to neighbors with similar surface normals (preserving edges).
3. Iteratively updating the elevations in the DEM to match the smoothed normal field.

References: Lindsay, John et al (2019): LiDAR DEM Smoothing and the Preservation of Drainage Features. Remote Sensing, Vol. 11, Issue 16, https://doi.org/10.3390/rs11161926

.. seealso:: This is a port of the WhiteboxTools `FeaturePreservingSmoothing`_ algorithm.

Parameters

Basic parameters

Label	Name	Type	Description
Input layer	INPUT	[raster]	Digital Terrain Model raster layer
Band number	BAND	[raster band]	The band of the DEM to consider
Filter radius (pixels)	RADIUS	[numeric: integer] Default: 5	Radius of the filter kernel. A radius of 5 results in an 11x11 kernel.
Normal difference threshold (degrees)	THRESHOLD	[numeric: double] Default: 15.0	Maximum angular difference (in degrees) between the normal vector of the center cell and a neighbor for the neighbor to be included in the filter. Higher values result in more neighbors being included, producing smoother surfaces. A range of 10-20 degrees is typically optimal.
Elevation update iterations	ITERATIONS	[numeric: integer] Default: 3	Number of times the smoothing process (elevation update) is repeated. Increasing this value from the default of 3 will result in significantly greater smoothing.
Maximum elevation change Optional	MAX_ELEVATION_CHANGE	[numeric: double] Default: 0.0	The allowed maximum height change of any cell in one iteration. If the calculated change exceeds this value, the elevation remains unchanged. This prevents excessive deviation from the original surface.
Z factor	Z_FACTOR	[numeric: double] Default: 1.0	Vertical exaggeration. This parameter is useful when the Z units differ from the X and Y units, for example feet and meters. You can use this parameter to adjust for this. Increasing the value of this parameter will exaggerate the final result (making it look more "hilly"). The default is 1 (no exaggeration).
Output layer	OUTPUT	[raster] Default: Save to temporary file	Specify the output hillshade raster layer. :ref:`One of <output_parameter_widget>`:

Advanced parameters

Label	Name	Type	Description
Creation options Optional	CREATION_OPTIONS	[string] Default: ''	For adding one or more creation options that control the raster to be created (colors, block size, file compression...). For convenience, you can rely on predefined profiles (see :ref:`GDAL driver options section <gdal_createoptions>`). Batch Process and Model Designer: separate multiple options with a pipe character (|).

Outputs

Label	Name	Type	Description
Output layer	OUTPUT	[raster]	The output smoothed raster layer

Python code

Algorithm ID: native:rasterfeaturepreservingsmoothing