Licensed to Map (What happened to Los Angeles?!)

I recently got back from the State of the Map - USA conference. It was great and you should have been there! But for those who weren't... I presented one session on Saturday afternoon with the same title as this post. Instead of just putting my slides out there I thought I would write a blog post to tell more of the story. This is a fairly long post but don't worry, it has a lot of pictures! (click to see full resolution)

So, the license change. It happened. We lost some data. But what happened before that to try and save as much as we could? And what exactly did we lose?

First, a brief timeline:

• Many moons ago, the OSM Foundation voted to change our license from Creative Commons to the Open Database License. This actually happened before I knew that OSM existed.
• In order to make the change, permission had to be secured from everyone who had contributed map data to the database.
• Contributions from anyone who did not agree to the new terms had to be removed from the database.
• At the end of 2011 the board set April 1st, 2012 as a target date for the license switch. This turned out to be wildly optimistic but at least it was a concrete goal to shoot for instead of just an ongoing process with no end in sight.
• The process of removing non-relicensable data was done by a bot that went through the entire database in the 2nd half of June
• After a little more cleanup, the first ODbL planet file was finally delivered in September.

Even though the April 1st target date was not really reasonable to hit, (especially in hindsight of course) it still gave the community something to work towards. And work we did.

Contacting inactive mappers

The first priority was to contact undecided users to make them aware of the change and that they needed to log in and indicate a decision. There were several rounds of emails sent out from the foundation to undecided users, trying to get them to respond. In addition to the emails from the foundation, users actively contacted other people in their area to try and make them aware of the decision. Lastly, the foundation supplied the account email address of some of the accounts with the most map data to a small group of volunteers for more targeted contact.

The result of this contact effort can be seen in this graph that I have been presenting since the beginning of the process:

The green line corresponds to the scale on the left while the red line follows the scale on the right. Of those who responded, it was a 99.5% landslide in favor of re-licensing their data. You can see that the people who were opposed to the change were very quick to log in and enter their decision. The big bumps in the green line clearly show when the mass emails were being sent out by the foundation.

Remapping using TIGER 2011

The license change mapping process I talked about in my previous post works well where there is still some clean data to go off of and you're just having to redo some work that a decliner did in splitting ways or adding some nodes to refine the geometry. But what about when an entire area is on the chopping block? I present the OSM Inspector view in Glendale, CA:

The area I worked on was just south of here and was actually even worse although I didn't get a "before" screenshot. Less yellow, more red. Here is what it looked like on Simon Poole's "badmap" rendering. Pretty much the entire road network is going to get nuked:

Most of this data is from a single, very prolific contributor who is not likely to agree to the new terms. It is also highly unlikely that anyone in the area is going to be able to redo all of his work before April 1st. So I reached for a bigger paintbrush: TIGER 2011.

License Change Mapping

So far I have avoided saying anything about the OpenStreetMap license change on this blog. It is a very sensitive subject for a lot of people for a million different reasons. This is not a post about how right/wrong the license change is. I personally have agreed to the new terms but then again I don't really care what license my data gets redistributed under. While I prefer (in most situations) a share-alike clause, if we were switching to public domain instead of ODbL, I would probably still agree. Whatever.

But the license change is happening and we must prepare the map for it, ahead of the April 1 cutover date set by the license working group. Today I decided to take a look at what it would take to get I-70 in Kansas cleaned up, license-wise, and thought I'd share my findings. Note that this particular process may or may not apply to other areas. The interstate system is kind of special in that it was imported from a public domain source and has very long stretches that are identical except for tags that don't really matter. This means that there isn't really very much unique or unrecoverable information present. If there is a small section of road (say a bridge) that is dirty, it can just be removed and replaced from clean data that surrounds it plus imagery to verify that it is indeed a bridge. However whenever possible it is preferred to maintain the history of objects in OSM so I don't want to just nuke and replace large sections of I-70. Plus, deleting and recreating ways gets more complicated because of the route relations that they may be a part of.

A majority of I-70 in Kansas is already clean but there is still a noticeable fraction of dirty objects. The goal is to end up with all objects being "clean" to re-license under ODbL. First task: find dirty objects. For this I use the "License Change" view in the OSM inspector tool created by Geofabrik: http://tools.geofabrik.de/osmi/?view=wtfe