Provided by: gdal-bin_3.0.4+dfsg-1build3_amd64
NAME
gdal_contourBuilds vector contour lines from a raster elevation model.
SYNOPSIS
Usage: gdal_contour [-b <band>] [-a <attribute_name>] [-amin <attribute_name>] [-amax <attribute_name>] [-3d] [-inodata] [-snodata n] [-i <interval>] [-f <formatname>] [[-dsco NAME=VALUE] ...] [[-lco NAME=VALUE] ...] [-off <offset>] [-fl <level> <level>...] [-e <exp_base>] [-nln <outlayername>] [-p] <src_filename> <dst_filename>
DESCRIPTION
This program generates a vector contour file from the input raster elevation model (DEM). Starting from version 1.7 the contour line-strings will be oriented consistently. The high side will be on the right, i.e. a line string goes clockwise around a top. -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: (Since GDAL 2.4) provides a name for the attribute in which to put the minimum elevation of contour polygon. If not provided no minimum elevation attribute is attached. Ignored in default line contouring mode. -amax name: (Since GDAL 2.4) provides a name for the attribute in which to put the maximum elevation of contour polygon. If not provided no maximim elevation attribute is attached. Ignored in default line contouring mode. -3d: Force production of 3D vectors instead of 2D. Includes elevation at every vertex. -inodata: Ignore any nodata value implied in the dataset - treat all values as valid. -snodata value: Input pixel value to treat as 'nodata'. -f format: Create output in a particular format. Starting with GDAL 2.3, 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. -off offset: Offset from zero relative to which to interpret intervals. -fl level: Name one or more 'fixed levels' to extract. -e base: (Since GDAL 2.4) will generate levels on an exponential scale: base ^ k, for k an integer. -nln outlayername: Provide a name for the output vector layer. Defaults to 'contour'. -p: (Since GDAL 2.4) Generate contour polygons rather than contour lines.
C API
Functionality of this utility can be done from C with GDALContourGenerate().
EXAMPLE
This would create 10meter 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
AUTHORS
Frank Warmerdam warmerdam@pobox.com, Silke Reimer silke@intevation.de