[Talk-ca] Merging OSM + Geobase

[Daniel Bégin]

Hello all!

 

Let me add my words on that tread. But first let me quote Dave and William

 

"If the Geobase stuff is highly superior to the existing OSM stuff, I
promise you that the mappers doing the OSM work will come to you and ask for
the Geobase data" Dave Hansen

 

"To me it just makes no sense to just throw out the rich set of NS geobase
data for these areas, just because someone did a first pass at mapping it
out.  To be clear, creating a hybrid between the two data sets is exactly
what I'm proposing to do." William Lachance

 

I would agree with Dave and William.  We all wish to get the data uploaded
properly in respect with the work that has been done already.

 

OSM makes it easy to create/modify/improve our - and everyone else data -
just to get the best of it!  I wouldn't feel bad seeing "my" roads improved,
even if the only remaining information from my original ways is a tag of
some type (or nothing at all!) but I wouldn’t if it is just deleted without
been replaced.

 

Wish data is better? Are we talking about geometry, content? It’s not always
the same!  

 

I’ve scanned wide areas around Sherbrooke, Quebec, Montreal and Ottawa using
canvec, osm and gps tracks downloaded from osm. Usually, when multiple gps
tracks where available, the tracks show that the geobase/canvec geometry was
the best. So, I thing that geobase/canvec gives us the best geometry frame
to built on. The data is structured (snap at intersections) and its accuracy
is usually good. Why don't we just add the existing osm information to it?  

 

However, there are sometime discrepancies. So?  Why don’t we use theses
multiple gps tracks to correct geobase geometry? I wouldn’t change geobase
geometry for another gps track but when more than 10 tracks are saying the
same thing – yes!

 

The osm data content is often richer than geobase/canvec. Street/Road name
for many provinces, pedestrian/cycle/bus
 paths, and more. Why don't we just
add it to geobase/canvec geometry when it’s available?  Furthermore, because
we work in community, the osm map is updated on a daily basis (contrary to
geobase wish is usually 6-18 month and up to 5 years in Quebec).  That is
something no government agency could afford!

 

So, I would add the following proposition to the Sam’s merging procedure

-        Work on areas we can deal with (complete data correction/merging
before uploading it in osm - I prefer to take more time but upload it
properly.)

-        Upload your gps tracks in osm and make it public, even if
corresponding ways already exists – It will helps to confirm the best
geometry.

 

Hope it helps

 

Daniel Bégin

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