OpenStreetMap
From Wikipedia, the free encyclopedia
| OpenStreetMap | |
|---|---|
 OpenStreetMap of Cambridge |
|
| URL | http://www.openstreetmap.org |
| Type of site | Collaborative mapping |
| Registration | Optional |
| Owner | OpenStreetMap Foundation |
| Created by | Steve Coast |
OpenStreetMap (OSM) is a collaborative project to create free editable maps. The maps are created using data from portable GPS devices and other free sources. Users can also create new routes or update existing ones using the given editing tools.
The map data and rendered maps are licensed under Creative Commons Attribution-ShareAlike 2.0 license
Contents |
[edit] Wiki map
The makers of OpenStreetMap are aiming for a wiki-like approach to map editing. Inspired by sites such as Wikipedia, the map display features a prominent 'Edit' tab, taking the user to a simple editing interface.
Also in keeping with wiki concepts, the back-end data structures include a full revision history.
[edit] History
OpenStreetMap was founded in July 2004 by Steve Coast. In April 2006 OSM began a process of transforming itself into a foundation.
- "The OpenStreetMap Foundation is an international non-profit organisation dedicated to encouraging the growth, development and distribution of free geospatial data and to providing geospatial data for anybody to use and share."
In July 2007, the OSM Foundation held the first OSM international conference, named "The State of the Map".
[edit] Mapping process
The map data in the system so far has mostly been built from scratch, through a collaborative mapping process. This normally begins with users uploading data onto OSM from their handheld GPS units or by tracing from aerial imagery (where permission is given). This is followed by a manual editing process, creating "nodes" and "ways", and tagging these with key-value pairs to represent information about the different types of street, names of the streets etc.
[edit] Yahoo! aerial imagery agreement
A special agreement has been made with Yahoo! to allow OpenStreetMap to make use of their vertical aerial imagery. The online editing tools are permitted to display the imagery as an overlay, and OpenStreetMap contributors may create their vector based maps as a derived work, released with an free and open license.
[edit] Data format
OpenStreetMap uses a topological data structure
- Nodes are points with a geographic position
- Ways are groups of nodes, representing a polyline or polygon
- Relationships are groups of nodes and ways which can be assigned certain properties
- Tags can be applied to nodes, ways or relationships and consist of name=value pairs
Up to version 0.4 of its protocol, an intermediate element between nodes and ways (segments) was also used.
The Ontology of map features (the meaning of tags) is maintained on a wiki.
[edit] Software
GPS and Data Collection
- GPSBabel - convert tracklogs
- AFTrack - Symbian 60v3 for Nokia mobile 'phones live tracking and routing software, from version 1.03 onwards
- BSGPS - Windows CE tracking software
Data Editing
Map Viewing
- Online Ajax-style OpenLayers-based slippy map interface. Displaying map tiles rendered by:
- Mapnik renderer
- Osmarender using XSLT to generate SVG as part of the Tiles@home distributed map-rendering project.
- Desktop
- Marble free and open source geographical map application using OSM for KDE.
- Kosmos - a lightweight open source OSM map rendering application, designed for rendering maps interactively and for setting up a local tile map server.
- OSMMap - Desktop Tool for browsing the OSM Maps (using Mapnik and Osmarender)
- Phone and GPS displays
- Gosmore
[edit] Data sources
- GPS tracklogs recorded by people out walking, cycling, and driving, combined with their notes and photos from the journey
- Local knowledge
- Public domain sources:
- Landsat 7 satellite imagery
- Prototype Global Shorelines (PGS)
- TIGER data of the United States
- Out-of-copyright Ordnance Survey maps
- Satellite and aerial images
- Ability to derive maps from Yahoo! Maps imagery
- Contributed datasets
- AND Automotive Navigation Data data for Netherlands, China, India
[edit] External links
- www.openstreetmap.org - Project page
- Project Wiki
- Featured map images
- OpenStreetMap in the Press. OpenStreetMap wiki.
