Summer Dispatch From The Telenav Map Team

It has been an exciting summer! Besides our regular work, there was the annual State of the Map conference that we were all really looking forward to. We launched a new ImproveOSM web site. OpenStreetCam dash-cams are distributed to OSM US members. And more. Read all about it in our Summer Dispatch below!

State of the Map

Quite a few of us got to go to State of the Map in Milan, Italy! Our team hosted four presentations at the conference, and we are really happy with the interest and feedback we received. We made a lot of new map friends as well!

All SOTM presentations were recorded and posted on YouTube, so if you missed any of us, you can watch the presentations at your leisure:

Alina and Bogdan presenting our Machine Learning stack at SOTM 2018

We also had a booth at the conference where we talked about ImproveOSM and OpenStreetCam, and where 6 lucky winners received a Waylens OpenStreetCam dashboard camera!

Excited crowd right before one of the Waylens cameras is being given away!

Mapping

We continue to map in Canada, the United States, and Mexico. As always you can track our work on GitHub. We have been focusing a lot on adding missing road names for the larger metropolitan areas in the US. Our typical workflow is to identify local government road centerline data sources, verify the license, process them with Cygnus to find changed / new names, and manually add the names if we can verify them.

Local road centerline data the team identified in Colorado

We are excited that the US community is looking to build an overview of available road centerline databases from (local) governments. We hope the ones we identified can help bootstrap this initiative.

We also published some MapRoulette challenges around this topic. 

ImproveOSM

Right on time for State of the Map, we launched a complete redesign of improveosm.org, our portal for everything Telenav❤️OSM. The new site gives you quick access to our OSM initiatives, data and tools. Check it out!We also released more than 20 thousand new missing roads locations. These are added to the existing database of currently more than 2.4 million missing road locations. An easy way to start editing based on these locations is to download the ImproveOSM plugin for JOSM.

Locations of the new Missing Roads locations

OpenStreetCam

The steady growth of OpenStreetCam continues. Almost 4.5 million kilometers of trips are in the OSC database. This amounts to about 165 million images!

We started a collaboration with OpenStreetMap US to run a Camera Lending program. Through the program, OSM US members can apply to borrow a custom Waylens Horizon camera for up to three months. The camera captures high resolution images for OSC and uploads them automatically. Almost 20 mappers have a camera already, and they have driven about 30 thousand kilometers in the past couple of months!

The passenger’s seat of our Camera Man ToeBee, as he gets ready to dispatch a bunch of Waylens cameras

That’s a wrap for our summer dispatch folks! Thanks for reading and keep an eye on the blog for more from the Telenav Map Team. Be sure to follow us on Twitter as well @improveOSM and @openstreetcam. 👋🏼

 

Facebooktwittergoogle_plus

Map Metrics for OSM are now available

Telenav’s OSM team just released a portal where you can view different metrics on OSM.

Unlike other metrics views that are already available, this new tool for the OSM community is focused especially on navigation attributes like length of navigable roads, number of turn restrictions, signposts and many more, in total 22 of such metrics are available. You can check it out at https://metrics.improveosm.org

About the data

Metrics are computed weekly and should be available on the portal at the end of each week. Metrics are generated for the whole world using as input the planet pbf downloaded from the official mirrors made available by OSM community

Metrics are available starting with 8th February 2016. In the top left corner, you can choose to see them by week, by month or by quarter. We also have a nice feature for all OSM enthusiasts! For each metric in the left menu you have a small info button where you see exactly what the metric means: complete description and the rules we applied when computing them, which tags where used, if we counted ways, nodes or relations etc.

How do we do it?

The platform was built using Apache Spark. Using big data technologies enabled us to have metrics for the whole world: on countries, states, counties and a few metropolitan areas (metros are available only in North America for now). In order to use Apache Spark, we had to convert pbf to parquet first, so we achieved this using a parquetizer that is open source and can be found here.  After we have the parquets, using Spark’s DataFrame API we managed to have these metrics available in just a couple of hours.

We have also made the latest parquet files available for general use here.

If you have any suggestions or feedback, please do not hesitate to contact us. You can find details in the About section.

Happy mapping!Facebooktwittergoogle_plus

Cygnus – conflation at your fingertips!

This is a follow-up blogpost after the State Of the Map US 2017 conference held in Denver.

The process of conflation in GIS is defined as the act of merging two data layers to create one layer containing the features and attributes of both original layers.

Cygnus is a tool that compares external data with OSM, giving you a result file in JOSM XML format with all the changes. The comparison is made in a non-destructive way, so no OSM ways are ever deleted or degraded.

Workflow

NOTE – The license compatibility between the local data file and OSM has to be taken into account before adding anything in OSM. Also, please follow the OSM import procedures if you are planning to add external data to OSM.

First of all you need to have a shapefile with local data in WGS84 spatial reference. This shapefile has to be filtered in different ways, depending on the tags you want to compare. For example, if you want to compare oneways, make sure to have a flow-direction/oneway/etc. attribute in the shapefile.

Translation

The first thing that has to be taken care of is to assure a proper attribute translation. I created a simple example for this exercise. I don’t want to get neck-deep in too many technical details so the main focus remains the process as a whole. I kept the attribute information for this example straightforward:

In order to create an OSM file from this data, I wrote a simple translation file that will be used together with ogr2osm.

Next, run the below command to obtain the OSM file.

python ogr2osm.py simple_streets.shp -t simple_translation.py -o simple_output.osm

Finally, I converted the OSM file to PBF using osmosis, because Cygnus requires a PBF file as input.

Cygnus goes to work!

Now that you have gone through the pre-processing of the local data file, we can offer it to Cygnus for processing. Note that your upload needs to be small-ish – the spatial extent needs to be smaller than 50×50 km and the file needs to be 20MB or smaller in size.

The interface of the Cygnus service is very simple – there are just two pages:

  • the home page where you add new jobs
  • the job queue page where you can see your progress and download the result

If your input file was uploaded successfully, Cygnus will go to work. Your job will be added to the back of the queue. When it’s your turn, Cygnus will read your PBF file, and download the OSM data for the same extent, using Overpass API. It will then compare your upload with the existing OSM data and produce the output file that you can download from the job queue.

NOTE – Everyone’s jobs are listed here, so be careful not to touch other users’ stuff.

Process the output in JOSM

Once Cygnus gives us the output, we can open it in JOSM and inspect it. This is by far the most important, and time consumig, step. Even though Cygnus does a best effort to connect ways where needed, it acts conservatively so it will not snap ways together that do not belong together.

Here are a few ways that got properly connected to the existing highway=secondary:

But there are situations where the distance was too far so Cygnus did not snap:

In this case, you need to manually connect the ways if that is appropriate.

When you are finally satisfied with your manually post-processed conflation result, you can go ahead and merge it with the OSM data and upload it!Facebooktwittergoogle_plus

OSMTime in Cluj featuring MapRoulette

OSMTime is a monthly OSM mapping event organized by Telenav colleague Beata Jancso. Telenav hosts the events in the Cluj-Napoca office  and sponsors with pizza. Usually Bea chooses a theme and sometimes there will also be a speaker with an interesting OSM related topic.

While visiting the Telenav Romania office in Cluj last week, I was lucky to also catch an OSMTime event. The theme of the evening was ‘Mapping Roundabouts using MapRoulette’. Being the person behind MapRoulette, Bea asked me to do a quick introduction. Colleague Bogdan Gliga also presented the metodology he used to detect missing roundabouts from massive amounts of probe data. (He wrote about that topic here as well.)

OSMTime Cluj with Bogdan presenting
OSMTime Cluj with Bogdan presenting

After the presentations and pizza, the 25 or so mappers logged on to MapRoulette to start with the new Missing Roundabouts challenge. Most people had not used MapRoulette before, so I was glad that everyone was getting the hang of it quickly. Most of the problems and questions were not about MapRoulette but about what is a roundabout exactly, and what is the difference between a roundabout and a mini_roundabout and a traffic_circle. (The OSM wiki helps out a little here.)

At the end of the evening, the mappers in the room already made a good dent in the challenge, which has more than 4500 tasks total.

I had a great time, thanks to Bea for organizing the OSMTime events every month and spreading the word. If you are in the Cluj-Napoca area, you may want to subscribe to the OSMTime meetup so you know when the next one takes place. Or look for an OpenStreetMap meetup in your area and meet local mappers!Facebooktwittergoogle_plus