Die freie Weltkarte nutzen und mitgestalten.
Von Frederik Ramm
und Jochen Topf.
3.10.2011 | Frederik Ramm
Our OSM Inspector web site is an important part of many a mapper’s toolbox. It has a series of, daily updated, debug views on OSM data, highlighting potential problems from invalid multipolygons over strange tagging or faulty geometries to missing address data.
The OSM Inspector, or OSMI for short, has several thematic views (like “geometry”, “tagging”, “boundaries”), each of which again supports a number of individually selectable layers that highlight a specific kind of problem. OSMI displays its results over an OSM base map, and you can select individual bug reports and get more information about them, or even download a list of errors for further processing. There’s extensive documentation on the OpenStreetMap Wiki.
Worldwide Routing View
While most views have always shown data computed in-house at Geofabrik, one of our views, the routing view, presents data that comes from an algorithm developed by Pascal Neis of OpenRouteService fame, and is sponsored by Skobbler. The routing view attempts to highlight obstacles to routing – mostly roads that are not connected when they should be, but also duplicate roads that may lead to strange routing results.
We do not have a sponsor for running this routing view world-wide on a daily basis right now, but we have run it once for the non-Europe part of the planet, and you can try it out here:
We’ll try to update this once a week or so. (The normal, sponsored routing view for Europe with daily updates is here.)
In all, OSMI has data collected by three different toolchains; one of them works globally and feeds e.g. the tagging, multipolygon, and general geometry debug views; the other two, including the routing view toolchain, currently do Europe only and would require re-writing or more hardware to cope with the whole planet.
It has always been possible to access OSMI views through WMS for use in other applications, especially as a background layer in editors. Users of the popular Potlatch editor were however unable to make use of this as Potlatch does not support WMS backgrounds. We have therefore configured OSMI to serve tiles as well. (We’re using the excellent open source MapProxy for that.)
If you are using Potlatch, you can now add any or all of the following background layers:
Those marked (*), and additionally all the public transport views offered by OSMI, are currently only available for Europe. For the public transport views, use the URL components “ptri” (rail infrastructure), “ptnri” (non-rail infrastructure), “ptf” (ferries), “pts” (stops), “ptn” (network).
Note that the tiles for each view will always show all available layers at the selected zoom level; when using tiles, you cannot toggle the visibility of individual layers like you can when using OSMI through its web interface. Also, the key to colours and symbols is only available within OSMI. Therefore, even if you plan to use the tiles in your editor, it might make sense to familiarize yourself with the data presentation on OSMI first!
We hope that these changes help to further improve quality awareness and, in consequence, data quality in OSM, and we’re happy to work with potential sponsors on extending these services to support more frequent updates, additional analyses, or a wider geographical coverage.