[Imports] tiff, dwg and nad83

[Michael Krämer]

Hi Frank,

Am 14.04.2012 20:52, schrieb Frank Cox:
> I live in a small city that is currently just a dot or blob on the
> OpenStreetMap. I discussed this matter with the guy at City Hall who is in
> charge of engineering, mapping and surveying and he stated that he would likely
> be willing to provide the data for our city so it can be added if I can find
> out exactly what you require and how to get it to you.

 From your mail signature I assume that your are talking about Melville, 
Saskatchewan. I agree that there isn't much mapped yet. But luckily 
there is decent Bing imagery available so I could not resist to trace a 
few more roads...

> He told me that his data is currently in Tiff and Autocad DWG files, tied to a
> GPS coordinate system called, I believe, NAD83. I wasn't smart enough at the
> time to write that number down at the time, but I'm pretty sure that's what he
> said.  He also said that he can convert his data into certain other formats, but
> he didn't specify exactly which ones.

I think tiff is only used for raster data while OSM is using vector 
data. So the only use for tiff I can see might be to use it as 
background for manual tracing.

Honestly I don't know if there is a path from DWG into OSM. But I found 
something in the help system: 
http://help.openstreetmap.org/questions/518/how-do-i-import-map-data-from-a-dwg-file-to-openstreetmap 
Generally one of the key aspects of an import is to set up the correct 
mapping for the attributes (type of roads etc.). If your import would 
give only the geometry you wouldn't have gained too much over tracing 
from images...

> My current knowledge of this stuff is pretty much nil. My question is, what
> would it take to convert this data to a format that can be uploaded to
> OpenStreetMap? If it's something that would be quick and easy to do then he
> would probably do it himself. If it's an involved process, I told him that I
> might volunteer to do it myself if he will provide me with the data.

Depending on what kind of data you would like to get into OSM you might 
want to consider to trace it manually e.g. from Bing, ideally in 
connection with some GPS-traces to check if the Bing images are well 
aligned or not. But this doesn't give all information - street names are 
missing to name just one rather important example. But as the city is 
not that big it might adde be rather quickly, too.

If your are considering to add buildings, that would be a different 
story. Mapping all buildings would take considerably more time, of course.

> The first step, and the reason why I'm here, is to find out exactly what would
> be involved in doing this, and then I can see about getting any required
> permissions from the City to use their data, and go from there.

I am personally not completely familiar with the license requirements 
for an import. So I hope someone else will jump in here.

Best regards,
	Michael