[Talk-se] Mapbox Organized Editing

Thu Mar 20 21:35:24 UTC 2025

Forgot to mention, if one suspects a geometry error in NVDB one can as a 
Swedish citizen (not sure about availability in foreign countries) take 
a peek at minkarta.lantmateriet.se and use "terrängskuggning" overlay 
with semi-transparancy so you see the road geometry below. The 
goverment's 1x1 meter DEM is very accurate measured via diff-gps + laser 
from airplane (lidar), and you can usually discern the roads in that. 
The DEM is not refreshed as often as NVDB though, so if there are new 
roads or a road is moved etc the DEM may be outdated.

On 2025-03-20 21:56, Anders Torger wrote:

> While there quality in NVDB does vary (it's a collection of multiple 
> sources) and geometry simplifications does occur, it's on average very 
> good. You cannot get the same accuracy from Bing or ESRI imagery, if 
> you want to get similar precision from ortophoto you would need 
> lantmäteriet's own. Sure if you have your own diff-GPS system you can 
> get more precise, but most maps from some sort of orthophoto, usually 
> with limited elevation correction leading to fairly large positional 
> errors.
> 
> Ideally you should use NVDB + Orthophoto + strava heatmap for sanity 
> checking + local knowledge where available. I've mapped tens of 
> thousands of roads in this manner in northern Sweden and quality of 
> NVDB is very good, while roads mapped on (especially older) ortophoto 
> in hilly regions can be very far off the mark. In city geometry stuff 
> get a bit more complicated, because there may be simplifications made 
> for navigation which may not match with OSM tradition, and there you 
> need to deviate at times. We have an ongoing manual import project with 
> documentation of limitations and caveats. You should never import 
> blindly, that's why the NVDB import project (or rather manual merging) 
> takes such long time. If you see errors like duplicated geometries, 
> clearly the mapper hasn't paid much attention to his or her merging 
> effort. Any source if misused leads to poor results.
> 
> It's best to use multiple sources and if working in Sweden NVDB should 
> for sure be one of them, and if the only positional data you have is 
> NVDB and an ortophoto from Bing or Esri, NVDB is nearly always better 
> positioned, with the exception of geometry simplification possibly 
> occurring on multi-lane roads, or sometimes very new forestry roads 
> with preliminary geometry and other rare exceptions. Naming of forestry 
> roads can be wonky in places, as the reporting can be patchy and 
> approximate depending on forestry company responsible for the 
> reporting. Naming of roads in cities are usually of very high quality.
> 
> The problem with OSM in Sweden is that the coverage can be patchy in 
> places where there are few active mappers, and some mapping can be 
> rather outdated. The big cities are usually well covered, or home 
> cities of super mappers. There are large areas in Sweden which is only 
> occasionally paid attention to, and there mapping work from people 
> without access to the ground is needed, and in such a situation using 
> NVDB in a responsible way as one of the key sources is the best way to 
> go.
> 
> However, if the mapper doesn't really want to make the effort to use 
> NVDB responsibly and not knowing about its limitations or how you 
> relate to existing mapping, it's best to not use it of course.
> 
> /Anders
> 
> On 2025-03-20 13:07, Peter Svensson wrote:
> 
> I disagree. The only things that shows exact locations of Swedish roads 
> are the ground itself. Everything else is approximations and 
> simplifications which are by definition "not exact". I've lost count of 
> how many things I've cleaned up after various NVDB import efforts, such 
> as incorrect names and duplicated/questionable geometries.
> 
> I encourage use of other sources than NVDB for mapping missing roads.
> 
> With regards,
> 
> zvenzzon
> 
> Den tors 20 mars 2025 12:31Markku Siipola via Talk-se 
> <talk-se at openstreetmap.org> skrev:
> 
> Your answers shows you are not aware of NDBD, the National road 
> database. This source should always be used, and not any source. The 
> NVDB shows the exact locations of Swedish roads. It's waste of time of 
> not using this db.
> 
> Den 2025-03-20 kl. 08:38, skrev Valeria Yukovich via Talk-se:
> Hello, Snusmumriken! Thank you for the questions.
> We will be using available sources which are appropriate for mapping on 
> OSM (satellite and street-level imagery, for example). Besides that, we 
> will be also using Mapbox telemetry data and GPS traces in cases when 
> there is limited evidence. More information about Mapbox telemetry data 
> can be found here: https://www.mapbox.com/telemetry [1].
> Speaking about our experience with other countries, we mostly 
> encountered missing roads in newly built residential areas and around 
> commercial objects, which we did not map in cases if the evidence 
> (street-level imagery or up-to-date satellites, information from the 
> telemetry) was not enough for mapping.
> 
> On Wed, Mar 19, 2025 at 12:18 PM Snusmumriken 
> <snusmumriken.mapper at runbox.com> wrote: On Tue, 2025-03-18 at 16:46 
> +0300, Valeria Yukovich via Talk-se wrote:
>> Hello from the Mapbox team!
>> 
>> Our team has been mapping missing roads since May (as described
>> here: https://community.openstreetmap.org/t/mapbox-organized-editing-
>> missing-roads/113678) and currently we are preparing to expand the
>> effort to Sweden.
> 
> Hi
> 
> I have basically two questions:
> - What sources will you be using in Sweden?
> - What are the most common problems you've encountered in other
> countries?
> 
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Links:
------
[1] https://www.mapbox.com/telemetry
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