OSMCOASTLINE_FILTER(1)

NAME

osmcoastline_filter - filter coastline data from OpenStreetMap file

SYNOPSIS

osmcoastline_filter --output=OUTPUT_FILE INPUT-FILE

osmcoastline_filter --help

DESCRIPTION

osmcoastline_filter is used to filter all nodes and ways needed for building the coastlines from an OSM planet. The data is written to the output file in PBF format.

This output file will be a lot smaller (less than 1%) than the original planet file, but it contains everything needed to assemble the coastline and land or water polygons.

If you are playing around or want to run osmcoastline several times with different parameters, run osmcoastline_filter once first and use its output as the input for osmcoastline.

osmcoastline_filter can read any file format supported by libosmium (in particular this is PBF, XML, and OPL files), but write only PBF files. PBF files are much smaller and faster to read and write than XML files. The output file will first contain all ways tagged “natural=coastline”, then all nodes used for those ways (and all nodes tagged “natural=coastline”). Having the ways first and the nodes later in the file is unusual for OSM files, but the osmcoastline and osmcoastline_ways programs work fine with it.

OPTIONS

-f, --format
    Set output format options (default: pbf).

-h, --help
    Display usage information and exit.

-o, --output=OSMFILE
    Where to write output (default: none).

-v, --verbose
    Enable verbose output.

-V, --version
    Display program version and license information.

EXAMPLES

Run it as follows:

    osmcoastline_filter -o coastline-data.osm.pbf planet.osm.pbf

SEE ALSO

•   osmcoastline(1), osmcoastline_ways(1)

•   Project page (https://osmcode.org/osmcoastline/)

•   OSMCoastline in OSM wiki (https://wiki.openstreetmap.org/wiki/OSMCoastline)

COPYRIGHT

Copyright (C) 2012-2025 Jochen Topf <jochen@topf.org>. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.

CONTACT

If you have any questions or want to report a bug, please go to https://osmcode.org/contact.html

AUTHORS
Jochen Topf <jochen@topf.org>.