gdal_contour - Builds vector contour lines from a raster elevation
model.
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>
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.
- -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.
- -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.
- -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.
Functionality of this utility can be done from C with
GDALContourGenerate().
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
Frank Warmerdam warmerdam@pobox.com, Silke Reimer
silke@intevation.de