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Public Transport Workshop

28.05.2009 | Jochen Topf

There are many questions around mapping public transport related things in OSM. Should stops be tagged on the traffic way (like the highway or railway) or next to it (say where the bus stop sign stands)? How can you tie together several platforms of one railway station? What is the relationship between a subway line, the platform where it stops and the subway entrance? How should bus lines or subway lines be tagged and what about different variants of the same line? There are many more questions like this. Upon invitation from Geofabrik some people from the German OpenStreetMap community met in Karlsruhe on May 16th 2009 to discuss these issues and make some progress. Twelve people attended this meeting, including Melchior Moos, the creator of the OSM public transport slippy map at www.öpnvkarte.de and Thomas Reincke from the public transport authority of Aachen. Of course Frederik Ramm and me were also present.

Sebastian Schwarz, a student at the Karlsruhe University of Applied Sciences, is currently doing his diploma thesis with Geofabrik on this topic. He looked into previous discussions in the OSM community as well as how other organisations have been modelling public transport data. In this workshop he presented his findings and his ideas for improvements. The discussion then ranged over many topics and I think we found good solutions for many problems. Of course many compromises needed to be done and the ideas we came up with are not the end of the discussion but just one further step. We had to keep current practice in mind and tried to make things as simple as possible but still allow the complex material to be tagged in a way useful for renderers and other uses of the data.

The main topics were:

  • Clear differentiation between infrastructure (the actual “hardware” like the rail tracks itself or the stops) and network information (like bus lines and subway lines) relating to this infrastructure
  • More consistent tagging of different types of transport (Why is it “halt” for trains but “bus_stop” for buses? Why is one placed usually on the rail itself, the other next to the street?)
  • Introduction of a new “public_transport” tag key
  • Clustering of stops into “stop areas” and “stop area groups” to model large train stations etc.
  • Clear differentiation between “stop positions” (where the vehicle stops), platforms (where people wait and enter the vehicles) and entrances (for instance for subways)
  • Differentiation between railway routes describing longer stretches of possibly named railways and the public transport lines using those railways

Much more detail is available on the following Wiki pages:

Once the information has stabilized somewhat we’ll move those pages to a more “official” location.

Feel free to leave comments on the talk pages. Or discuss on the transit mailing list.

Sebastian has also worked on the OSM Inspector and added five new views that show different aspects of public transport mapping in OSM:

  • Railway Infrastructure – Shows the different types of rails
  • Non-railway Infrastructure – All non-rail infrastructure such as bus guideways, escalators or taxis stands
  • Ferries – Shows ferry lines and terminals
  • Stops – Shows all kinds of stops including stop position, accesses (such as platforms) and stop areas
  • Network – Shows public transport lines

Suggestions on how to improve those views are welcome.

Die 2., überarbeitete und erweiterte Auflage unseres Buches “OpenStreetMap – Die freie Weltkarte nutzen und mitgestalten” ist fertig und ab sofort erhältlich.

Für die Neuauflage haben wir nahezu alle Kapitel überarbeitet und Bilder aktualisiert. Sieben Kapitel sind neu hinzugekommen, viele wurden erweitert. Insgesamt ist der Umfang des Buches um 64 Seiten angewachsen – von 288 Seiten bei der ersten Auflage auf nun 352 Seiten, 32 davon in Farbe wie schon in der 1. Auflage.

Weitere Infos unter www.openstreetmap.info.

Die wichtigsten Änderungen:

  • Aktualisierung des OSM-Datenformates und der API für Version 0.6
  • Neues Kapitel zum Editor Merkaartor
  • Neues Kapitel zum Renderer Kosmos
  • Viele Erweiterungen und Aktualisierungen bei der Erklärung der Map Features
  • Neues Kapitel zu fortgeschrittenem Tagging mit Erklärungen zu Adressen/Hausnummern, Routen, u.v.m.
  • Neues Kapitel zu Hilfsprogrammen für Mapper: Data View, Data Browser, OSM Inspector, ITO OSM Mapper und Tagwatch
  • Umfangreiche Aktualisierungen in den Kapiteln zu Mapnik, Osmosis, Navigation und mobile Nutzung und zu den APIs
  • Neues Kapitel “Editieren für Fortgeschrittene”
  • Vollständig überarbeitetes Kapitel zum Import und Export von OSM-Daten

Geofabrik Tools Revamped

5.02.2009 | Frederik Ramm


We have added a slippy map and a map comparison view to our tools page. Yes, we know, there are some of these around already, but ours have received a lot of love in the finer detail.

The slippy map, for example, has a map grid layer that clearly shows tile coordinates and boundaries on all zoom levels, making it easy to spot rendering artifacts at tile boundaries. You can also choose to see not only the mouse cursor position, but also the current extent of the map view in degrees. The map also offers quick links to a series of other OpenStreetMap services – and when you switch from our map to, say, the map display at openstreetmap.org, the viewport will of course be retained.

The map comparison tool offers a side-by-side full-screen comparison of any two map sources, and also has a slaved cross-hair pointer for exact location of detail.

All Geofabrik tools are now linked through a drop-down in the top-right corner so that you can easily switch from the map view to the Inspector or the map comparison page – and back again – without having to zoom to the same location all the time.

We have also polished the entry page, so head over there and give it a test drive!

Oberpfalz macht Fortschritte

27.12.2008 | Frederik Ramm

(This posting refers to a high-profile, ongoing tracing activity in Germany where OSM was granted access to official aerial imagery. The remainder of the posting is in German only.)

Das bayerische Landesamt für Vermessung und Geoinformation hat OpenStreetMap Mitte Dezember Luftbilder für das Gebiet der Oberpfalz zur Verfügung gestellt und das Abdigitalisieren explizit erlaubt (Wiki-Seite). Die Hauptarbeit dabei wird von der Community getan; die Geofabrik stellt einen WMS und Serverplatz für die Bilddaten bereit und hat eine spezielle OSM Inspector-Ansicht eingerichtet, die alle Objekte verzeichnet, deren Quellenangabe auf diese Luftbilder verweist.

Eine statistische Auswertung der vorliegenden Daten zeigt deutliche Fortschritte (die Auswertung basiert auf einer Zählung der Straßenkilometer der jeweiligen Straßenklassen):

Das südlich von der Oberpfalz liegende, gleich große “Vergleichsgebiet”, das wir zu statisischen Zwecken mitbeobachten, zeigt kaum Entwicklung:

Auch in der Anzahl unterschiedlicher Benutzer, die im Gebiet aktiv sind, und in der Gesamtzahl der Nodes in den OSM-Daten der jeweiligen Region, zeigt sich die deutliche Wirkung der nun verfügbaren Luftbilder:

OSM Inspector Christmas Update

19.12.2008 | Jochen Topf

Since the launch of the OSM Inspector (http://tools.geofabrik.de/osmi/) at the end of October many people have used it to improve OSM data. We got lots of great feedback, have fixed many bugs, and added several new views.

In time for christmas we have some presents for OSM Inspector users:

  • OSM Inspector works in IE and Safari now
  • A last update timestamp is shown
  • There is a new ‘info’ button next to the view pulldown that links to the documentation of this view on the wiki
  • There is a link to the OSM data browser directly from the selection
  • Permalinks are shorter in most cases
  • Some smaller bug fixes

In the last months we have added the “Boundaries” view depicting administrative boundaries between countries, districts, etc. Also there is a “Kreisgrenze” view to help German users with tagging local boundaries and an import of boundaries we are planning. Also for German users is the “Strassen NRW” view which shows road data from North Rhine-Westphalia that we received from a government agency.

To celebrate the new Inspector version we added a brand new view today: The “Tagging” view shows basic problems with tags such as misspelled keys and highlights objects tagged as to-do item or with FIXME. Try it out at http://tools.geofabrik.de/osmi/?view=tagging .

We have created a mailing list for OSM Inspector “power users” at http://lists.geofabrik.de/listinfo/osm-inspector . Sign up there if you want to receive early notification of new features, or discuss possible enhancements.

From day one it was possible to look at OSM Inspector layers from WMS clients or download the data through WFS, but we never documented this. We have now added documentation for WMS and WFS access to the wiki
at http://wiki.openstreetmap.org/wiki/OSM_Inspector/WxS . This (semi-official) API allows you to get rendered maps or the raw data from OSM Inspector layers to use in your own applications. Please read
the documentation on the wiki carefully before using this and subscribe to our mailing list to keep abreast of changes if you use this API.