[Imports] N50 imports from Kartverket (The Norwegian Mapping Authority)

[Tor]

16. juni 2014 kl. 10:18 skrev Christoph Hormann <chris_hormann at gmx.de>:

> On Sunday 15 June 2014, Tor wrote:
>> 
>> To decide if an N50 waterway is a stream or a river the following
>> criteria are used:
>> 1) Local knowledge
>> 2) Name ('bekk' means stream,
>> 'elv' or 'å' both mean river; no name implies that it's only a
>> stream) 3) N50 VANNBR tag where code 2 is 1–3m, code 3 is 3–15m and
>> code 4 is ≥15m
> 
> This much i understood, what i wanted to know is under what 
> conditions the conversion generates waterway=stream and waterway=river 
> or natural=wood, natural=scrub and landuse=forest.
> 
> It is a good idea and common practice to document this attribute 
> conversion scheme on the wiki, for examples see:
> 
> http://wiki.openstreetmap.org/wiki/CanVec:_Hydrography_%28HD%29
> http://wiki.openstreetmap.org/wiki/Antarctic_Digital_Database/Data
> 
> Doing manual verification of taggings is a good idea but still you 
> should have reasonable and documented defaults for those values and in 
> case of mandatory manual verifications adding a fixme tag meant to be 
> removed after the manual check is a good idea since it helps keeping 
> track of the process.

As far as I know, none of the tools available for converting from SOSI
format to shape or OSM convert the tags. Until someone write a tool that
does this, this part of the conversion has to be done manually (or
semi-automatically).

For waterways I guess it's easiest to set the defaults based on VANNBR,
and then verify manually before import:
VANNBR=2 – waterway=stream
VANNBR=3 – waterway=river
VANNBR=4 – waterway=river

For woods/forests the default would be natural=forest.

-- 
Tor