builds vector contour lines from a raster elevation model
Usage: gdal_contour [-b <band>] [-a <attribute_name>] [-3d] [-inodata]
[-snodata n] [-f <formatname>] [-i <interval>]
[-off <offset>] [-fl <level> <level>...]
[-nln <outlayername>]
<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.
- -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, default is shapefiles.
- -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.
- -nln outlayername:
- Provide a name for the output vector layer. Defaults to "contour".
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
