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GDALLOCATIONINFO(1)                  GDAL                  GDALLOCATIONINFO(1)

NAME
       gdallocationinfo - Raster query tool.

SYNOPSIS
          Usage: gdallocationinfo [--help-general] [-xml] [-lifonly] [-valonly]
                                  [-b band]* [-overview overview_level]
                                  [-l_srs srs_def] [-geoloc] [-wgs84]
                                  [-oo NAME=VALUE]* srcfile [x y]

DESCRIPTION
       The  gdallocationinfo  utility provide a mechanism to query information
       about a pixel given its location in one of a variety of coordinate sys-
       tems.  Several reporting options are provided.

       -xml   The output report will be XML formatted for convenient post pro-
              cessing.

       -lifonly
              The only output is filenames production  from  the  LocationInfo
              request against the database (i.e. for identifying impacted file
              from VRT).

       -valonly
              The only output is the pixel values of  the  selected  pixel  on
              each of the selected bands.

       -b <band>
              Selects  a band to query.  Multiple bands can be listed.  By de-
              fault all bands are queried.

       -overview <overview_level>
              Query the (overview_level)th overview (overview_level=1  is  the
              1st overview), instead of the base band. Note that the x,y loca-
              tion (if the coordinate system  is  pixel/line)  must  still  be
              given with respect to the base band.

       -l_srs <srs_def>
              The coordinate system of the input x, y location.

       -geoloc
              Indicates  input  x,y points are in the georeferencing system of
              the image.

       -wgs84 Indicates input x,y points are WGS84 long, lat.

       -oo NAME=VALUE
              Dataset open option (format specific)

       <srcfile>
              The source GDAL raster datasource name.

       <x>    X location of target pixel.  By default the coordinate system is
              pixel/line unless -l_srs, -wgs84 or -geoloc supplied.

       <y>    Y location of target pixel.  By default the coordinate system is
              pixel/line unless -l_srs, -wgs84 or -geoloc supplied.

       This utility is intended to provide a variety of  information  about  a
       pixel.  Currently it reports:

       • The location of the pixel in pixel/line space.

       • The  result  of a LocationInfo metadata query against the datasource.
         This is implement for VRT files which will report the file(s) used to
         satisfy requests for that pixel, and by the raster.mbtiles driver

       • The  raster  pixel  value  of  that  pixel for all or a subset of the
         bands.

       • The unscaled pixel value if a Scale and/or Offset apply to the band.

       The pixel selected is requested by x/y coordinate on the command  line,
       or  read from stdin. More than one coordinate pair can be supplied when
       reading coordinates from stdin. By default pixel/line  coordinates  are
       expected.   However with use of the -geoloc, -wgs84, or -l_srs switches
       it is possible to specify the location in other coordinate systems.

       The default report is in a human readable text format.  It is  possible
       to instead request xml output with the -xml switch.

       For scripting purposes, the -valonly and -lifonly switches are provided
       to restrict output to the actual  pixel  values,  or  the  LocationInfo
       files identified for the pixel.

       It  is anticipated that additional reporting capabilities will be added
       to gdallocationinfo in the future.

EXAMPLES
       Simple example reporting on pixel (256,256) on the file utm.tif.

          $ gdallocationinfo utm.tif 256 256
          Report:
          Location: (256P,256L)
          Band 1:
              Value: 115

       Query a VRT file providing the location in WGS84, and getting  the  re-
       sult in xml.

          $ gdallocationinfo -xml -wgs84 utm.vrt -117.5 33.75
          <Report pixel="217" line="282">
              <BandReport band="1">
                  <LocationInfo>
                  <File>utm.tif</File>
                  </LocationInfo>
                  <Value>16</Value>
              </BandReport>
          </Report>

       Reading location from stdin.

          $ cat coordinates.txt
          443020 3748359
          441197 3749005
          443852 3747743

          $ cat coordinates.txt | gdallocationinfo -geoloc utmsmall.tif
          Report:
            Location: (38P,49L)
            Band 1:
              Value: 214
          Report:
            Location: (7P,38L)
            Band 1:
              Value: 107
          Report:
            Location: (52P,59L)
            Band 1:
              Value: 148

AUTHOR
       Frank Warmerdam <warmerdam@pobox.com>

COPYRIGHT
       1998-2021

                                 Dec 27, 2021              GDALLOCATIONINFO(1)

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