Here in the U.S., we have been using the convention of tagging exit information on the highway=junction node using the poorly documented exit_to tag. The rest of the world has been using destination=, and now that I start to think about this problem more, I can see why.

Let’s take this example of the junction of I-70 and the Baltimore beltway I-695.

(Have you used Mapillary? It’s pretty awesome and unlike Google Streetview, OpenStreetMap explicitly does have permission to map from the images. It’s pretty easy and fun to contribute your own, too.)

How to tag this so that navigation and other software could make sense of it?

Currently, the only relevant tags on the junction node are ref:left=91B and ref:right=91A indicating the exit / junction numbers. There is nothing on the `_link’ ways to indicate destination.

… See full entry

We created a new MapRoulette challenge over at Telenav: Crossing Ways. As always with the Telenav-generated challenges, this one is US only, because we currently only process OpenStreetMap data for the United States. We are working on extending support for other regions.

TL;DR –> On to MapRoulette!!

The Crossing Ways challenge is pretty straightforward and should make for an easy challenge for novice mappers looking for something to fix. It detects ways that cross, but neither way is tagged as a bridge or tunnel. Here is an example:

If you open this up in iD or JOSM, you will be able to tell the required resolution from the aerial imagery:

… See full entry

From time to time someone will ask me: ‘How do I find out who my fellow local mappers are?’

That can be a surprisingly hard question to answer. You can go to your user page and see a few people who have indicated their ‘home location’ to be near yours. That does not work so well for a variety of reasons:

1. Not all people set their home locations. My guess is most people don’t.
2. People don’t update their home locations when they move.
3. The home location is not necessarily where that person is mapping.

… See full entry

Over at Telenav we have been busy comparing the GPS traces of drivers using our navigation apps against OSM data. This is fun work and sometimes leads to really useful results. One of our recent studies involved comparing what we think are one-way streets to the corresponding OSM ways. The process is quite simple: count how many traces following a given street go in one direction, and how many go in the other. If the number for one direction is close to zero, the street is probably one-way. The outcome depends on the confidence level you apply, but it turns out that there are more than 100 thousand OSM ways that probably should be marked with a oneway tag, but aren’t.

One. Hundred. Thousand.

I don’t know about you, but I think that would make for a really great MapRoulette challenge. So that’s what I did, and here it is.

But how do you know if a street should be one-way without having eyes on the ground? It turns out the aerial imagery provides helpful hints. Let me show you what I look at to verify the one-way-ness of a street using just JOSM and the Bing layer.

Let’s look at this case here:

… See full entry

Those first few MapRoulette challenges did not keep you busy very long: most tasks in the Zorro / Tangled / Wrong One Ways challenges were fixed within the first few days. Dang! We were not prepared for that and had to take MapRoulette down for a little while because there was nothing to do…

But now we’re back! This time with Ways Needing Smoothing. We detect ways that have suspiciously sharp angles and ask you to smoothen them out. Here’s a great example:

Opening this task up in JOSM reveals that there’s more to fix than just the one sharp angle that was detected:

… See full entry

We are about to launch the new version of MapRoulette! Finally! The most obvious changes are that you now sign in using your OSM account - so you can track your and other mappers’ progress, and multiple challenges being available to choose from! We will launch the day after tomorrow with four new challenges to start with: the familiar Zorro Ways, ways with overlapping parts, wrong one way ways (if you know a better name, let me know..) and tangled ways. More to come!

Behind the scenes much more has changed. There is now an API for challenge providers to post their own challenges (let me know if you want access), challenges can have an area associated with them so you will be able to choose a challenge that is local to you, and they also have difficulty levels. The entire application has also been rebuilt from the ground up to be more stable, scalable, and allow more flexibility for different types of challenges in the future. If you want to see how MapRoulette is built, check out MapRoulette on Github.

So, on March 12, head on over to maproulette.org and start fixing!

I keep coming across beautiful OSM-based maps! Here is one for Poland:

Go explore for yourself here.

We are trying out something new here in Salt Lake City, Utah: Saturday Mapternoons. The next one is tomorrow, and I am looking forward to it. Saturday Mapternoons are a mix of mapping, catching up with fellow local OpenStreetMappers and geeking out over all things geo. If you’re in the area, join us!

Check out all upcoming OpenStreetMap Utah events on our meetup page.

(This was originally posted on my blog. I want to start posting here more instead. This is a start.)

If you follow the blog at openstreetmap.us, you will have heard about the Battle Grid. It is a map that shows you where recent TIGER data is different from OpenStreetMap data. Because TIGER has improved a lot over the years, and has kept up reasonably well with new road construction, a big difference between TIGER and OSM tells us that OSM likely needs some love. Here is how the battle grid looked until today:

Cells with a lot of difference between TIGER and OSM are brighter, and as a simple way of prioritizing the cleanup and update work, I colored the cells that are within a Census CDP orange, and the rest green.

As of today the Battle Grid will look like this, instead:

… See full entry

I was just looking at my user map to see what’s going on with OpenStreetMap users who are in my area. It turns out many of them have zero edits. They signed up for OSM, even put in the additional, optional effort of setting their home location, but never edited. Why?

That is the Big Question we want to try and answer in the Welcome Working Group. That, and trying to come up with solutions for the ‘retention problem’. Simply said, provide a warmer welcome to new users. Our focus will not be on editors. Rather, we want to look into documentation, welcome messages, incentives to map.. You could say: the social and educational dimensions of welcoming newcomers to the community.

Do you think you have something to contribute to this process? Helping (re-)write documentation? Research new user behavior? Another angle you would like to explore? All it takes is constructive ideas and some time to act on them. We meet on #osm-strategic every Thursday at 1900 UTC.

I'm back in Amsterdam for a bit. I haven't really have time to do any mapping yet but I'm happy to see that the area where I'm currently staying is now littered with POIs - bars, restaurants, shops, all the goodness that the Leidseplein area is well known for. Even the recently started Starbucks Invasion into the Netherlands is already reflected. Most places have URL and/or phone number data associated with them. It looks like we have user stroet43 to thank for most of the recent improvements in this area. Great work! I don't think I've met him or her. Maybe at the upcoming New Year's Drinks in Utrecht? I don't see a link to it anywhere on the OSM wiki, but they're in Utrecht this Sunday. Inquire on talk-nl if you want to know more I guess. See you there?

I got on the remapping train. It looks like Salt Lake is pretty severely affected because of a small number of decliners. I approached one of them, and he is not changing his mind. Approaching the other few soon. In the mean time, I'm focusing on the main road network. There's even a few miles of interstate that will need to be remapped. A lot of work, and not the most fun job. On the other hand, I get to (re)visit some places that could use some improvement.

You can reliably measure how bored I am on any given day by counting how many trees I have mapped on that day.

to set up a local Amsterdam OSM mapping clubje

did IJplein this afternoon and some Java-eiland

We had a good first day of the Amsterdam Mapping Party. I made my very first contribution to OSM: my oen lovely neighborhood Staatsliedenbuurt. And because the weather was super, I took the dog for an extra long walk around the garden complex 'Nut en Genoegen' ('Purpose And Joy').