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gis_data [2014/08/07 09:45]
mstraub [Use OSM data with QGIS]
gis_data [2015/02/11 16:57] (current)
mstraub [Use OSM data with QGIS]
Line 1: Line 1:
 +====== OpenStreetMap ======
  
 +===== OSM map data=====
 +
 +==== Use OSM data with QGIS ====
 +
 +Step 1: Download OSM data, e.g. an export from Geofabrik in the space-saving binary pbf-format
 +<code bash>
 +wget http://​download.geofabrik.de/​europe/​austria-latest.osm.pbf
 +</​code>​
 +
 +Step 2: [[http://​www.gdal.org/​ogr/​drv_osm.html|Configure GDAL]] (which is used by QGIS to import OSM data) to import all attributes you are interested in
 +<​code>​
 +/​usr/​share/​gdal/​1.10/​osmconf.ini
 +</​code>​
 +
 +Step 3: Extract your area of interest and convert it into a SpatiaLite (SQLite) database - a format QGIS can handle easily. The -spat argument takes latitude / longitude in the following order: -spat minLon minLat maxLon maxLat
 +<code bash>
 +#ogr2ogr -f "​SQLite"​ -spat minLon minLat maxLon maxLat snippet.db austria-latest.osm.pbf
 +ogr2ogr -f "​SQLite"​ -spat 16.34 48.19 16.36 48.20 snippet.db austria-latest.osm.pbf
 +</​code>​
 +
 +
 +Alternative:​ use Osmosis to snip your area of interest (you could also use --write-xml to create an OSM XML file to e.g. open it in JOSM)
 +<code bash>
 +osmosis --read-pbf austria-latest.osm.pbf --bounding-box left=16.34 bottom=48.19 right=16.36 top=48.20 --write-pbf snippet.pbf
 +</​code>​
 +
 +Step 4: Use [[https://​github.com/​anitagraser/​QGIS-resources/​tree/​master/​qgis2/​osm_spatialite|pretty predefined styles]] to visualize the map. 
 +
 +Sources: \\
 +http://​anitagraser.com/​2014/​05/​31/​a-guide-to-googlemaps-like-maps-with-osm-in-qgis \\
 +http://​anitagraser.com/​2014/​06/​07/​toner-lite-styles-for-qgis/​
 +
 +===== OSM GPX planet =====
 +
 +In April 2013, OSM [[http://​blog.osmfoundation.org/​2013/​04/​12/​bulk-gpx-track-data/​|announced]] a new dataset containing GPS tracks.
 +[[http://​planet.openstreetmap.org/​gps/​|Full dataset]] and [[http://​zverik.osm.rambler.ru/​gps/​files/​extracts/​index.html|extracts]] (e.g. for [[http://​zverik.osm.rambler.ru/​gps/​files/​extracts/​europe/​index.html|Europe]]) are available. The OSM wiki of course has more [[https://​wiki.openstreetmap.org/​wiki/​Planet.gpx|information]] for this dataset.
 +
 +==== What's inside ====
 +
 +Looking at a small excerpt - [[http://​zverik.osm.rambler.ru/​gps/​files/​extracts/​usa/​us-pacific.tar.xz|us-pacific.tar.xz]],​ downloaded 2013-04-23 - the following can be said:
 +
 +The compressed dataset has 16MB, the uncompressed has 340MB.
 +
 +
 +{{ :​structure.png |}}
 +
 +The **metadata file** contains an entry per track. Each entry has an id, a timestamp depending on the privacy setting, ​
 +
 +The tracks are grouped in directories according to their [[http://​wiki.openstreetmap.org/​wiki/​Visibility_of_GPS_traces|visibility]]. Public, trackable and identifiable tracks are included. Private tracks are not contained within the dataset.
 +
 +Uploaded **GPX tracks** must have a timestamp for each GPS positions. However the timestamps may be anonymised (e.g. by using [[http://​wiki.openstreetmap.org/​wiki/​JOSM/​Plugins/​EditGpx#​Anonymize_timestamps|JOSM]]. ​
 +
 +The dataset may contain tracks that show obvious **errors** (e.g. spatial error and a track is located in the ocean).
gis_data.txt ยท Last modified: 2015/02/11 16:57 by mstraub