GDAL-RASTER-TPI(1)                   GDAL                   GDAL-RASTER-TPI(1)

NAME
       gdal-raster-tpi - Generate a Topographic Position Index (TPI) map

       Added in version 3.11.


SYNOPSIS

          Usage: gdal raster tpi [OPTIONS] <INPUT> <OUTPUT>

          Generate a Topographic Position Index (TPI) map

          Positional arguments:
            -i, --input <INPUT>                                  Input raster dataset [required]
            -o, --output <OUTPUT>                                Output raster dataset [required]

          Common Options:
            -h, --help                                           Display help message and exit
            --json-usage                                         Display usage as JSON document and exit
            --config <KEY>=<VALUE>                               Configuration option [may be repeated]
            --progress                                           Display progress bar

          Options:
            -f, --of, --format, --output-format <OUTPUT-FORMAT>  Output format ("GDALG" allowed)
            --co, --creation-option <KEY>=<VALUE>                Creation option [may be repeated]
            --overwrite                                          Whether overwriting existing output is allowed
            -b, --band <BAND>                                    Input band (1-based index) (default: 1)
            --no-edges                                           Do not try to interpolate values at dataset edges or close to nodata values

          Advanced Options:
            --if, --input-format <INPUT-FORMAT>                  Input formats [may be repeated]
            --oo, --open-option <KEY>=<VALUE>                    Open options [may be repeated]

DESCRIPTION
       gdal raster tpi generates a single-band raster with values computed
       from the elevation. TPI stands for Topographic Position Index, which is
       defined as the difference between a central pixel and the mean of its
       surrounding cells (see Wilson et al 2007, Marine Geodesy 30:3-35).

       This subcommand is also available as a potential step of gdal raster
       pipeline

       Value -9999 is used as the nodata value.

       A nodata value in the target dataset will also be emitted if at least
       one pixel set to the nodata value is found in the 3x3 window centered
       around each source pixel. By default, the algorithm will compute values
       at image edges or if a nodata value is found in the 3x3 window, by
       interpolating missing values, unless --no-edges is specified, in which
       case a 1-pixel border around the image will be set with the nodata
       value.

   Standard options

       -f, --of, --format, --output-format <OUTPUT-FORMAT>
              Which output raster format to use. Allowed values may be given
              by gdal --formats | grep raster | grep rw | sort

       --co <NAME>=<VALUE>
              Many formats have one or more optional creation options that can
              be used to control particulars about the file created. For
              instance, the GeoTIFF driver supports creation options to
              control compression, and whether the file should be tiled.

              May be repeated.

              The creation options available vary by format driver, and some
              simple formats have no creation options at all. A list of
              options supported for a format can be listed with the --formats
              command line option but the documentation for the format is the
              definitive source of information on driver creation options.
              See Raster drivers format specific documentation for legal
              creation options for each format.

       --overwrite
              Allow program to overwrite existing target file or dataset.
              Otherwise, by default, gdal errors out if the target file or
              dataset already exists.

       -b, --band <BAND>
              Index (starting at 1) of the band to which the TPI must be
              computed.

       --no-edges
              Do not try to interpolate values at dataset edges or close to
              nodata values

GDALG OUTPUT (ON-THE-FLY / STREAMED DATASET)
       This program supports serializing the command line as a JSON file using
       the GDALG output format.  The resulting file can then be opened as a
       raster dataset using the GDALG: GDAL Streamed Algorithm driver, and
       apply the specified pipeline in a on-the-fly / streamed way.

EXAMPLES
   Example 1: Generates a Topographic Position Index (TPI) map from a DTED0
       file.

          $ gdal raster tpi n43.dt0 out.tif --overwrite

AUTHOR
       Even Rouault <even.rouault@spatialys.com>

COPYRIGHT
       1998-2025

                                  May 6, 2025               GDAL-RASTER-TPI(1)