tyrasd
osmtogeojson
Converts OSM data to GeoJSON. Try the demo!
- stable
- real OSM polygon detection
- proper OSM multipolygon support
- full support for extended Overpass API geometry modes
- well tested and proven
- fast
This code is used in and maintained by the overpass turbo project.
Usage
command line tool
Installation:
$ npm install -g osmtogeojsonUsage:
$ osmtogeojson file.osm > file.geojsonSupported command line options are shown with:
$ osmtogeojson --helpWhen working with extra large data files (≳ 100 MB) it is recommended to run the programm with a little extra memory to avoid process out of memory errors. The easiest way to do this is by running the command as node <path-to-osmtogeojson> and setting the --max_old_space_size=… parameter to the available memory size in MB (osmtogeojson typically needs about 4-5 times the input data size). On a Unix system, you can use the following command:
$ node --max_old_space_size=8192 `which osmtogeojson` large.osm > large.geojsonnodejs library
Installation:
$ npm install osmtogeojsonUsage:
var osmtogeojson = require('osmtogeojson');
osmtogeojson(osm_data);browser library
<script src='osmtogeojson.js'></script>
osmtogeojson(osm_data);API
osmtogeojson( data, options )
Converts OSM data into GeoJSON.
data: the OSM data. Either as a XML DOM or in OSM JSON.options: optional. The following options can be used:flatProperties: If true, the resulting GeoJSON feature's properties will be a simple key-value list instead of a structured json object (with separate tags and metadata). default: falseuninterestingTags: Either a blacklist of tag keys or a callback function. Will be used to decide if a feature is interesting enough for its own GeoJSON feature.polygonFeatures: Either a json object or callback function that is used to determine if a closed way should be treated as a Polygon or LineString. read more
The result is a javascript object of GeoJSON data:
GeoJSON
The GeoJSON produced by this library will include exactly one GeoJSON-feature for each of the following OSM objects (that is everything that is also visible in overpass turbo's map view):
- all unconnected or interesting tagged nodes (POIs)
- all ways (except uninteresting multipolygon outlines)
- all multipolygons (simple multipolygons with exactly one closed outer way are present via their outer way)
All data is given as a FeatureCollection. Each Feature in the collection has an id property that is formed from the type and id of the original OSM object (e.g. node/123) and has the member properties containing the following data:
type: the OSM data typeid: the OSM idtags: a collection of all tagsmeta: metainformaton about the feature (e.g. version, timestamp, user, etc.)relations: an array of relations the feature is member of. Each relation is encoded as an object literal containing the following properties:role(membership role),rel(the relation's id) andreltags(contains all tags of the relation)tainted: this flag is set when the feature's geometry is incomplete (e.g. missing nodes of a way or missing ways of a multipolygon)
If the option flatProperties is set to true, the properties object will not contain any nested object literals, but directly provide a concise id, meta data and the tags of the respective OSM object.
