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GDAL extraction

Clip raster by extent

Description

Clips any GDAL-supported raster file to a given extent. The algorithm is derived from the GDAL grid utility .

Parameters

Input layer [raster]
Input raster file.
Nodata value, leave as none to take the nodata value from input [string]

Defines a value that should be inserted for the nodata values in the output raster.

Default: none

Clipping extent [extent]

Extent that should be used for the output raster. Selects only features within the specified bounding box.

Default: 0,1,0,1

Additional creation parameters [string]

Optional.

<put parameter description here>

Default: (not set)

Outputs

Output layer [raster]
Output raster layer.

Console usage

processing.runalg('gdalogr:cliprasterbyextent', input, no_data, projwin, extra, output)

See also

Clip raster by mask layer

Description

Clips any GDAL-supported raster by a vector mask layer. The algorithm is derived from the GDAL grid utility .

Parameters

Input layer [raster]
Input raster layer.
Mask layer [vector: polygon]
Defines the vector mask for clipping the raster.
Nodata value, leave as none to take the nodata value from input [string]

Defines a value for the no-data areas of the input raster.

Default: none

Create and output alpha band [boolean]

Creates an alpha band for the result. The alpha band then includes the transparency values of the pixels.

Default: False

Keep resolution of output raster [boolean]

The resolution of the output raster will not be changed.

Default: False

Additional creation parameters [string]

Optional.

<put parameter description here>

Default: (not set)

Outputs

Output layer [raster]
Output raster layer.

Console usage

processing.runalg('gdalogr:cliprasterbymasklayer', input, mask, no_data, alpha_band, keep_resolution, extra, output)

See also

Contour

Description

Extracts contour lines from any GDAL-supported elevation raster. The algorithm is derived from the GDAL contour utility .

Parameters

Input layer [raster]
Input elevation raster.
Interval between contour lines [number]

Defines the interval between the contour lines in the given units of the elevation raster.

Default: 10.0

Attribute name (if not set, no elevation attribute is attached) [string]

Optional.

Defines the attribute name for the field containing the values of the contour lines. If nothing is defines the default name will be ‘ELEV’.

Default: ELEV

Additional creation parameters [string]

Optional.

<put parameter description here>

Default: (not set)

Outputs

Output file for contour lines (vector) [vector]
<put output description here>

Console usage

processing.runalg('gdalogr:contour', input_raster, interval, field_name, extra, output_vector)

See also