gdal_footprint - Compute footprint of a raster.
gdal_footprint [--help] [--help-general]
[-b <band>]... [-combine_bands union|intersection]
[-oo <NAME>=<VALUE>]... [-ovr <index>]
[-srcnodata "<value>[ <value>]..."]
[-t_cs pixel|georef] [-t_srs <srs_def>] [-split_polys]
[-convex_hull] [-densify <value>] [-simplify <value>]
[-min_ring_area <value>] [-max_points <value>|unlimited]
[-of <ogr_format>] [-lyr_name <dst_layername>]
[-dsco <name>=<value>]... [-lco <name>=<value>]... [-overwrite] [-q]
<src_filename> <dst_filename>
The gdal_footprint utility can be used to compute the
footprint of a raster file, taking into account nodata values (or more
generally the mask band attached to the raster bands), and generating
polygons/multipolygons corresponding to areas where pixels are valid, and
write to an output vector file.
The nearblack utility may be run as a pre-processing step
to generate proper mask bands.
- --help
- Show this help message and exit
- --help-general
- Gives a brief usage message for the generic GDAL commandline options and
exit.
- -b <band>
- Band(s) of interested. Between 1 and the number of bands of the raster.
May be specified multiple times. If not specified, all bands are taken
into account. The way multiple bands are combined is controlled by
-combine_bands
- -combine_bands
union|intersection
- Defines how the mask bands of the selected bands are combined to generate
a single mask band, before being vectorized. The default value is
union: that is a pixel is valid if it is valid at least for one of
the selected bands. intersection means that a pixel is valid only
ifit is valid for all selected bands.
- -ovr
<index>
- To specify which overview level of source file must be used, when
overviews are available on the source raster. By default the full
resolution level is used. The index is 0-based, that is 0 means the first
overview level. This option is mutually exclusive with
-srcnodata.
- -srcnodata
"<value>[ <value>]..."
- Set nodata values for input bands (different values can be supplied for
each band). If a single value is specified, it applies to all selected
bands. If more than one value is supplied, there should be as many values
as the number of selected bands, and all values should be quoted to keep
them together as a single operating system argument. If the option is not
specified, the intrinsic mask band of each selected bands will be
used.
- -t_cs
pixel|georef
- Target coordinate system. By default if the input dataset is
georeferenced, georef is implied, that is the footprint geometry
will be expressed as coordinates in the CRS of the raster (or the one
specified with -t_srs). If specifying pixel, the coordinates
of the footprint geometry are column and line indices.
- -t_srs
<srs_def>
- Target CRS of the output file. The <srs_def> may be any of the usual
GDAL/OGR forms, complete WKT, PROJ.4, EPSG:n or a file containing the WKT.
Specifying this option implies -t_cs georef The footprint is reprojected
from the CRS of the source raster to the specified CRS.
- -split_polys
- When specified, multipolygons are split as several features each with one
single polygon.
- -convex_hull
- When specified, the convex hull of (multi)polygons is computed.
- -densify
<value>
- The specified value of this option is the maximum distance between 2
consecutive points of the output geometry. The unit of the distance is in
pixels if -t_cs equals pixel, or otherwise in georeferenced
units of the source raster. This option is applied before the reprojection
implied by -t_srs
- -simplify
<value>
- The specified value of this option is the tolerance used to merge
consecutive points of the output geometry using the
OGRGeometry::Simplify() method The unit of the distance is in
pixels if -t_cs equals pixel, or otherwise in georeferenced
units of the target vector dataset. This option is applied after the
reprojection implied by -t_srs
- -min_ring_area
<value>
- Minimum value for the area of a ring The unit of the area is in square
pixels if -t_cs equals pixel, or otherwise in georeferenced
units of the target vector dataset. This option is applied after the
reprojection implied by -t_srs
- -max_points
<value>|unlimited
- Maximum number of points of each output geometry (not counting the closing
point of each ring, which is always identical to the first point). The
default value is 100. unlimited can be used to remove that
limitation.
- -q
- Suppress progress monitor and other non-error output.
- -of
<ogr_format>
- Select the output format. Use the short format name. Guessed from the file
extension if not specified
- -overwrite
- Overwrite the target layer if it exists.
- <src_filename>
- The source raster file name.
- <dst_filename>
- The destination vector file name. If the file and the output layer exist,
the new footprint is appended to them, unless -overwrite is
used.
Post-vectorization geometric operations are applied in the
following order:
- optional splitting (-split_polys)
- optional densification (-densify)
- optional reprojection (-t_srs)
- optional filtering by minimum ring area (-min_ring_area)
- optional application of convex hull (-convex_hull)
- optional simplification (-simplify)
- limitation of number of points (-max_points)
This utility is also callable from C with
GDALFootprint().
- •
- Compute the footprint of a GeoTIFF file as a GeoJSON file using WGS 84
longitude, latitude coordinates
gdal_footprint -t_srs EPSG:4326 input.tif output.geojson
Even Rouault <even.rouault@spatialys.com>