Vi har blivit kontaktade angående huvudsakligen byggnadskartläggning som någon har gjort runt Hässleholm, t.ex. , varav mycket har ändrats från byggnad=hus till byggnad=ja.
Vad tycker alla om detta?
Med tanke på mängden redigering de gör verkar det möjligen vara automatiserat, så jag vet inte om något har diskuterats offentligt?
Tack
Graeme Fitzpatrick
Moderator
OSMF Data Working Group
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Hello Sweden!
We have been approached regarding predominantly building mapping that somebody has been doing around Hässleholm e.g. Changeset: 183369787 | OpenStreetMap , a lot of which has changed building=house to building=yes.
What is everybody’s thoughts on this please.
By the amount of editing they’re doing, it would appear o possibly be automated, so I don’t know iof anything has been discussed publicly?
It looks like this might be “manual” automation where large data-sets have been downloaded and re-tagged in JOSM. Nothing about this has been discussed in the community. And is not something I think the majority would agree with.
This is a type of data quality regression. building=yes specifies buildings of an unknown type where building=house is more specific to a single family home. This is clearly stated on the wiki too. There are of course other even more specific tags that can be used as well but this change would lower the data quality and should be reverted.
The user do not even have any sources specified in their changesets so very hard to know where the data comes from.
Looks like the user has done a lot of work to map out all missing and minor buildings in Hässleholms kommun. There are tons houses all over from before that are also tagged “building=yes”.
If the user can be convinced to not swap house->yes then I can only applaud the effort.
I’m also a bit worried about the source, the geometries of the added buildings are almost a perfect match with those from Lantmäteriet (the Swedish national mapping agency), example:
The issue here is that this data, if gotten from Lantmäteriet, has an incompatible license (CC BY 4.0, Lantmäteriet have explicitly denied the required exemptions, and there are additional terms that restrict usage in OSM context as well). Some municipalities provide the same data under more permissive/compatible licenses, but I cannot find that Hässleholm does so.
I also note that the changes are missaligned, see for example the small building under the 17 in the middle which in Lantmäteriets data is attached to the main building.
All taken together - dubious licensing, data quality, etc. I’d argue for reverting this ASAP rather than waiting for a response. Even if licensen is alright the import (which it almost definitely is) would probably have to be redone correctly (with preceeding discussion, correct tagging, non-duplicated nodes, etc.) anyway.
I can confirm that the source it Lantmäteriet .
Interesting with the duplicated nodes. Nothing JOSM found when I worked with it. Maybe better that someone with better experience remove my edits? Since I obviously caused duplicated nodes without knowing…
By the way, may I ask you where did existing buildings come from originally? They can’t have been drawn by hand, which I usually do. That would take enourmous amount of time all over Sweden.
Thats sort of how OSM works I hand-drew all the buildings in my kommun three times over until they were good enough.
JOSM should give you this
Maybe you just imported data without having existing data loaded. Try downloading over Vinslöv and validate. Anyway, the nodes can be fixed with one click. The license is the bigger issue.
Notera även att även om allt är okej med licens så finns det lite regler för hur man gör importer, bland annat för att säkerställa att det inte blir problem som med licensen eller de duplicerade noderna: Import/Guidelines - OpenStreetMap Wiki (detta gäller oavsett om du använder någon automatiserad process eller importerar manuellt)
Vi är många som gärna ser att sån här data som kommer in, så om du t.ex. kan få tag på byggnaderna från Hässleholm i passande licens (se Import/Getting permission - OpenStreetMap Wiki) så hjälper vi dig gärna navigera importprocessen.
Got through ~165k of them & thought Yay, then scrolled a bit further down the list only to find another ~175k! So ~340000 reverts later …
Sadly, yes, there will have been damage caused to good mapping, but unfortunately, when you have issues of that size, it’s unavoidable. All I can say is please look, & as you find problems, please fix them.
One strange one was Changeset: 183776337 | OpenStreetMap , which isn’t that big, but which brought up almost 300 conflicts? I’m afraid to say I took the easy way out of that one & have left it untouched for somebody local to check & fix! It may be easier to just go through & delete things where necessary, rather then revert?
The buildings are drawn by hand. That’s the basis of OSM. Look at my area of interest, Gothenburg. Almost every building, including greenhouses and outbuildings are mapped in the entire kommun. If you look at the changesets you’ll find that they are drawn by many user, incrementally and by great effort. That’s how it’s supposed to be done.
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