Our ImproveOSM pipeline produces a pretty impressive number of suggested roads missing from OSM, missing oneway tags, and missing turn restrictions, based on analysis of billions of GPS data points. We make the results available as frequent data dumps in CSV format. In this post, I want to look at a way to integrate this data into your OSM mapping workflow.
If you just want to see ImproveOSM data in JOSM wherever you are currently mapping, you can just use the ImproveOSM JOSM plugin. For advanced users who want more flexibility, or who want to use this data in different ways, this post offers some guidance.
The data dumps are available from here. For this example, I will work with the most recent Direction of Flow data file. This highlights ways with potential missing oneway tag. After downloading and unzipping it, you will have a CSV file of about 16.5 megabytes that looks like this:
wayId;fromNodeId;toNodeId;percentage;status;roadType;theGeom;numberOfTrips 148617028;1867720648;89191396;99.5378927911275;SOLVED;THROUGHWAY;LINESTRING(2.217821 48.922613,2.217719 48.922618,2.217408 48.922633);1082 33555379;322840377;322840383;98.6301369863014;INVALID;LOCAL_ROAD;LINESTRING(4.999815 47.34294,4.999957 47.343062,4.999965 47.34315);146 17271190;178942503;2341050872;100;OPEN;LOCAL_ROAD;LINESTRING(11.070503 50.139245,11.070525 50.139213,11.070616 50.139099,11.070693 50.139032);74 .....
Since the theGeom field is in WKT, you can import it as a layer in QGIS pretty easily. Let’s fire up QGIS (I use 2.18) and add a Delimited Text layer.
In the dialog, select the downloaded CSV file as the file source. Set the delimiter to semicolon. QGIS detected for me that the geometry was in the theGeom field, and of type WKT, but you can set that manually if needed:
Upon clicking OK, QGIS wants us to define which CRS the coordinates are defined in. Select WGS84.
Now, we have a layer of line geometries that correspond to OSM ways that may be missing a oneway tag.
To make the file more manageable, let’s limit our selection to one country. I get country boundaries from Natural Earth (a fantastic resource!). After adding the country borders to QGIS, I can perform a spatial query. Before you do this, select the country you are interested in. I pick Mexico as an example.
Bring up the Spatial Query window. If you don’t see this menu item, you will need to enable the Spatial Query plugin.
Select the ImproveOSM layer as the source, and the Natural Earth layer as the query layer. Make sure to check the ‘1 Selected geometries’ checkbox, so we limit our query to Mexico.
The matching features will now be selected in the ImproveOSM layer. Make sure that layer is selected in the Layers Panel before you select Layer -> Save As.. from the QGIS menu. In this dialog, choose GeoJSON as the output type. Select a destination filename. Make sure that the CRS is set to WGS84. Make sure the ‘Save only selected features’ is checked, and Save.
Now you have a GeoJSON file with all OSM way geometries that may need a oneway tag. You can load this file into JOSM, using its GeoJSON plugin. To organize your work going through these, I would recommend using the Todo plugin and add the GeoJSON features to the todo list.

