Interesting Tech Projects
Open Street Map Quick Start (JOSM)
This is a description of how to quickly get going with OpenStreetMap. It is primarily aimed at people who don’t have a GPS unit or don’t want to use one. It’s also aimed at people who want to quickly add something to their local area. It is not a replacement for the OSM wiki.
Get JOSM
First download the current version of JOSM, which is a Java based editor. You will also need to install Java 1.5. You can also read more about JOSM here and here.
Start JOSM. On the command line this is something like:
java -jar -Xmx512M josm-latest.jar
There are some JOSM plugins that I think are essential, and here is how to add them:
- Start JOSM
- Go to Edit -> Preferences
- Click on the plugins tab (looks like a wall socket/outlet)
- Click on “Download List”
- Check/tick the following: utilsplugin, validator, waydownloader
- Click on “OK”
- Restart JOSM
Next you need to tell JOSM your OpenStreetMap username and password.
- Go to Edit ->Preferences
- Click on the connection settings tab (looks like a planet)
- Enter your email address and password
- Click on “OK”
Next install the WMS Plugin for JOSM that will allow you to view Yahoo satellite images.
Download a Section of the Map
Next you will want to download the part of the map that covers your local area.
- Click on the Download From OSM toolbar button
- Check/tick “Download as a new layer”
- Drag the map with the right mouse button, zoom with the mouse wheel or Ctrl + arrow keys
- Drag a box with the left mouse button to select an area to download. Keep it small for now.
- Click on “OK” and wait a bit. It could take a few minutes so don’t give up too quickly
You will now be looking at a black screen with lots of lines on it. Zoom in to a few streets using the magnifying glass tool on the toolbar.
Get the Satellite Images
The next step is to get the satellite images so we can see how the streets compare with the real world.
- Go to WMS -> Yahoo Sat (may have a slightly different name depending on the JOSM version)
At the top right under the Layers heading a new layer should appear called “Yahoo Sat” or something like that. Wait a bit and the images should start to appear.
Edit the Map
It’s now time to start editing. It should be clear if a street is not aligned with the Yahoo images. If it isn’t then you can click on the Select tool on the toolbar and start dragging the nodes (small yellow boxes). Position a road over where it is in the satellite image.
Upload!
Once you have fixed a few roads click on the Upload to OSM toolbar button.
- Enter a description for the change
- Click on “Upload Changes”
Once complete you can go to your OSM account page and view your edits. The URL is http://www.openstreetmap.org/user/myusername/edits. Replace “myusername” with your user name. You should see your first edit!
After waiting a few minutes your changes should start to appear on the map. Mapnik (the default renderer) renders the lower zoom levels more frequently, so you should see your changes appear in stages and only in some zoom levels. After a day or so all the lower zoom levels should show your changes.
Some Notes
The Yahoo satellite images are not always in the right place, but it seems from my experience they are pretty good. However this is something to keep in mind.
Along with fixing streets, it’s also possible to add in schools, malls, hospitals, businesses, rivers, streams, parks, etc. all by using the satellite images. There is plenty to do!
Print article | This entry was posted by Andy on August 6, 2009 at 5:12 pm, and is filed under Mapping. Follow any responses to this post through RSS 2.0. Both comments and pings are currently closed. |
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