[Talk-ca] Imported frustrations

[john whelan]

It is a major problem, hopefully some one will run a bot and at least take
out the duplicate imports.  Many mappers only think in terms of paper so if
it looks OK on a render then its OK.

In Ottawa which is smaller and easier to handle we had a meeting of local
mappers who some time ago because of quality and reliability issues
basically agreed to rip out the existing roads and replace them with CANVEC
data and eventually that's more or less what we did.  There are those who
think what was done was incorrect and we should have respected the efforts
that had been made before.  Today it would be much harder to do because tags
get additional information added to them over time.  The benefit was that
you can route fairly well over Ottawa.

In OSM there is no easy answer on this one.  Different mappers map to
different standards.  CANVEC data is sometimes a little out of date so a
local mapper's mapping may well be more accurate than CANVEC data.  Not
everyone realises the importance of joining junctions together or even
cares.  If it looks OK on a render that's fine to them.

The only thing I can think of is a blitz where we use a team of mappers to
clean up an area at a time, perhaps it could become a winter project?  I've
made many, many corrections using http://keepright.ipax.at with JOSM and
Internet Explorer in Ottawa.  You can tell it to just pick out almost
junctions by the way so think in terms of coming up with a set of simple
procedures that can be easily followed then see if we can tap into some
spare mapping capacity somewhere.

Perhaps Richard come come up with a Canada OSM Newsletter that deals with
Canadian issues.  If you are a new mapper please join your ways to others so
routing software will work might be a suitable article.

An alternative would be to run the routing software over an OSM type
database that was just CANVEC imports.

Cheerio John


On 6 October 2011 14:45, Harald Kliems <harald.kliems at mail.mcgill.ca> wrote:

> Hi everyone,
> I've recently moved to Montreal from Upstate NY and have been mapping
> mostly in my neighborhood. When rendering a map for routing purposes for my
> bike, I noticed that the routing data for Quebec is often not that great.
> With the help of the great and powerful OSM Inspector I started to fix a
> bunch of these errors, but after a while I realized that their number is
> huge and they've all been caused by imports: In many cases (for examples see
> my current edit history
> http://www.openstreetmap.org/user/hobbesvsboyle/edits ) roads have been
> imported twice (CanVec 6 and Geobase or later CanVec version) and one
> version of the road is usually not linked with some or all of the
> crossroads. Finding and fixing these errors has been a huge timesuck and not
> much fun. As you can see here, the problem is pretty huge
> http://tools.geofabrik.de/osmi/debug.html?view=routing_non_eu&lon=-75.07164&lat=45.79735&zoom=8&opacity=0.98and I was therefore wondering if anyone has suggestions for a faster fix.
>
> What I've done so far is to use the OSM Inspector and take "unconnected
> roads" as an indication for identifying problematic areas. In JOSM I then
> glance over intersections and ways for duplicate and unconnected roads in
> that area. Sometimes it's fairly easy to see them, sometimes it's not. In
> addition, I'm using JOSM's validator to find additional problems.
>
> Does anyone have suggestions for speeding this up? And are those of you
> doing the imports aware of this problem?
>
> Frustrated,
>  Harald.
>
>
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