NAME
gdal_contour - gdal_contour builds vector contour lines from a raster
elevation model
SYNOPSIS
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>
DESCRIPTION
This program generates a vector contour file from the input raster
elevation model (DEM).
-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’.
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>