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Hello I have downloaded an OSM file for the state of Illinois in USA and was trying to extract the height information but it turns out that 99% of height information is no defined. Is there a way to have the height for all building polygons defined correctly? |
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OSM has 957,000 buildings in Illinois, of which only 43 have a (more or less) exact height information in the So, a partial answer to your question is: There is hardly a "correct" height for any building in Illinois, but there ought to be at least an approximate height for almost half (but certainly not all) buildings, through the building:levels tag. Tell us how exactly you tried to extract this information and we might guess what went wrong. The process to extract these heights is a bit long to explain in this forum. I basically cleaned up the OSM file to show only buildings, then extracted the attributes (Height and levels which I used to estimate the height value by multiplying the average storey height*# of level + average basement height). For the buildings with no height info nor level info, I estimated a height based on my knowledge of the city architecture. I finally combined all these attribute into one vector file with all these height info. I hope this helps. It would be really helpful to have accurate height information like what google earth does.
(09 Apr '14, 18:57)
Biabou
Here is an image of where I see the height as an attribute.
(09 Apr '14, 18:59)
Biabou
From the screenshot I guess you're using Global Mapper (which I'm not familar with). Perhaps it's showing "height" as something that you can search the data with because there's "height" information somewhere (in 43 places) in the data?
(09 Apr '14, 20:49)
SomeoneElse ♦
That is correct. Height is defined in the file. We just need the correct values for all the buildings not only 43 of them. Is that possible please?
(10 Apr '14, 01:31)
Biabou
2
If the data isn't in OSM, someone needs to put it there. One option would be for you to survey the remaining 956,957 buildings, or persuade 95,695 people to do 10 buildings each. If you don't fancy doing that, then a "plan B" might be to discuss with the local OSM community whether there's a source of building height data that you can use (either importing into OSM, after discussing with the community, or merging externally, if an import isn't an option).
(10 Apr '14, 01:56)
SomeoneElse ♦
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First of all, is this information in OSM ? I doubt that this is the first priority of any mapper.
Yes it is and I can see the height as an attribute in the OSM file that processed.
Can you give an example of where you "see the height as an attribute"?