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GDAL_CONTOUR(1) GDAL GDAL_CONTOUR(1) NAME gdal_contour - Builds vector contour lines from a raster elevation model. SYNOPSIS gdal_contour [--help] [--help-general] [-b <band>] [-a <attribute_name>] [-amin <attribute_name>] [-amax <attribute_name>] [-3d] [-inodata] [-snodata <n>] [-f <formatname>] [-i <interval>] [-dsco <NAME>=<VALUE>]... [-lco <NAME>=<VALUE>]... [-off <offset>] [-fl <level> <level>...] [-e <exp_base>] [-nln <outlayername>] [-q] [-p] [-gt <n>|unlimited] <src_filename> <dst_filename> DESCRIPTION The gdal_contour generates a vector contour file from the input raster elevation model (DEM). The contour line-strings are oriented consistently and the high side will be on the right, i.e. a line string goes clockwise around a top. --help Show this help message and exit --help-general Gives a brief usage message for the generic GDAL commandline op- tions and exit. -b <band> Picks a particular band to get the DEM from. Defaults to band 1. -a <name> Provides a name for the attribute in which to put the elevation. If not provided no elevation attribute is attached. Ignored in polygonal contouring (-p) mode. -amin <name> Provides a name for the attribute in which to put the minimum elevation of contour polygon. If not provided no minimum eleva- tion attribute is attached. Ignored in default line contouring mode. New in version 2.4.0. -amax <name> Provides a name for the attribute in which to put the maximum elevation of contour polygon. If not provided no maximum eleva- tion attribute is attached. Ignored in default line contouring mode. New in version 2.4.0. -3d Force production of 3D vectors instead of 2D. Includes eleva- tion at every vertex. -inodata Ignore any nodata value implied in the dataset - treat all val- ues as valid. -snodata <value> Input pixel value to treat as "nodata". -f <format> Create output in a particular format. New in version 2.3.0: If not specified, the format is guessed from the extension (previously was ESRI Shapefile). -dsco <NAME>=<VALUE> Dataset creation option (format specific) -lco <NAME>=<VALUE> Layer creation option (format specific) -i <interval> Elevation interval between contours. Must specify either -i or -fl or -e. -off <offset> Offset from zero relative to which to interpret intervals. For example, -i 100 requests contours at ...-100, 0, 100... Further adding -off 25 makes that request instead ...-75, 25, 125... -fl <level> Name one or more "fixed levels" to extract. -e <base> Generate levels on an exponential scale: base ^ k, for k an in- teger. Must specify either -i or -fl or -e. New in version 2.4.0. -nln <name> Provide a name for the output vector layer. Defaults to "con- tour". -p Generate contour polygons rather than contour lines. New in version 2.4.0. -gt <n> Group n features per transaction (default 100 000). Increase the value for better performance when writing into DBMS drivers that have transaction support. n can be set to unlimited to load the data into a single transaction. If set to 0, no explicit trans- action is done. New in version 3.10. -q Be quiet: do not print progress indicators. C API Functionality of this utility can be done from C with GDALContourGenerate(). EXAMPLE This would create 10-meter contours from the DEM data in dem.tif and produce a shapefile in contour.shp|shx|dbf with the contour elevations in the elev attribute. gdal_contour -a elev dem.tif contour.shp -i 10.0 AUTHOR Frank Warmerdam <warmerdam@pobox.com>, Silke Reimer <silke@inteva- tion.de> COPYRIGHT 1998-2025 Feb 11, 2025 GDAL_CONTOUR(1)
NAME | SYNOPSIS | DESCRIPTION | C API | EXAMPLE | AUTHOR | COPYRIGHT
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