Improve OSM Tool Highlight: Cygnus

Improve OSM is all about making OpenStreetMap better with the help of billions of GPS points that users of Scout apps and others contribute automatically. This allows us to identify missing roads, one-way streets and turn restrictions that are not in OSM yet. However, our OSM engineers think about other ways to help make OSM better as well. Looking at what is going on in the OpenStreetMap community, I see a lot of groups and individuals struggle with the challenge of using external data in OpenStreetMap. Many governments now open up data that was closed before. With proper caution and preparation, we may be able to use this data in OSM.

The technical challenge here is to combine the new, external data with what is already present in OSM. In the GIS world this is called conflation. There are some tools out there to help with this task, but they are hard to use. So we started to think about this from a practical point of view and a specific use case: what if you have an external database of just roads, and you want to add only the new roads to OSM?


We developed a tool that can do just that, and we called it Cygnus. I wrote about Cygnus on my OSM diary before, announcing it here and then writing about it being used by OSM user MikeN here. We added a link to the Cygnus web site to the ‘Other tools’ section of the ImproveOSM web site.

We made Cygnus as easy to use as possible, but it is still not straightforward. It should not be. Conflation is hard, and what you are doing is importing data into OSM, which should be done with the utmost caution! If you want to get started using Cygnus, please get in touch. We are happy to help!