WikiProject Belgium/Road completion project

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The Belgian community is building tools to make sure that any correction in the official open data road sets is made visible to the mapping community as quickly and as accurately as possible. As a first case, we would work with Wegenregister, from the Flemish government. But because it isn’t just Flanders that has released tools like this, we will try to build something that is easily scalable to any dataset of road centerlines worldwide.

For a better introduction, have a look at our project page

Related research

Preparing & comparing data

Our approach

Based on Mapbox QA tiles. First turn external data (Wegenregister in this case) into vector tiles. Ideally, this process can be plugged into a project like OSMlab's centerlines project.

Comparison code lives here [1] = Simple set-up: find roads that are probably geometrically missing in OSM.

In a later fase: generate errors by type, with different mapping solutions depending on the type

First focus roads that are both:

- "really missing in OSM"

- "named roads only", which are an easy category with very high quality. Already roughly 15-20.000 segments! This includes some paths, but in general "real" roads.

In the future:

- road types that need local survey

- tagging evaluation (name, road type)

- reversed check: roads that are missing in official road data

Alternative approaches


Using Postgis

Cygnus, a tool developed by Telenav, allows for data conflation of external road datasets and OSM road data. Advantages: it allows for faster mapping, because the original geometry is copied. Disadvantage: it becomes a real import (hence procedures), people might be tempted to import as many roads as possible rather than checking case by case. Many of the differences will probably be complicated situations, making an automated approach rather difficult.

Offering services

  • Mapping layers. Similar to [2]. Here as well, it might be useful to integrate with OSMlab centerlines somehow.
  • Microtasking.

Maproulette looks promising, but some questions remain:

  • The task lists can be updated using an API call. E.g. you want to hide tasks that continuous geometrical checking notices are done. Looks like the only way is cloning, reloading data, and hiding the old version. Is this also the case when working with external data? If so, what happens to fixed tasks?
  • Mark a task as "too hard" to group them for further analysis. However, not possible between "uh, I don't get it", and "needs a survey"
  • Is it possible to lock someone within the task? In the test project, you tend to sometimes randomly arrive in a different task.
  • are fixed and false positives removed from standard view (and is there a way to only see "advanced" tasks)?
  • make it possible to leave notes to the manager: e.g. "yes, I fixed this, but something special is going on here"
  • You can add a custom background map, which should be visible in the Maproulette interface.

To do:

  • write proper instructions. "Also check with GRB".
  • add a Wegenregister background map to the task.

Sample task: Sample dataset: