Ok, cool :)  Lots of great discussion points.Again, I'll try
to summarize with this info, and hopefully setting somethings as a
foundation.  (in story form)

Basic questions:

What do we want to accomplish with the OpenStreetMap project?
and
What do we want to accomplish from Geobase?

Here's IMO plus adding in everyone else's views (to the best of my ability)

By adding features that we are not likely to be able add the map ourselves,
we can import GeoBase data.

IF the prime purpose IS to complete the road network across Canada, then  in
doing so this will cause issues.  This is because, technically speaking.
 The GeoBase road database IS ALREADY the complete road network across
Canada. Period.  With future updates, this database, will ALWAYS be the
complete road and official road network for Canada.  It's a federally funded
database, with the goal of being the complete network.
So .. no matter how we twist and turn it, it will still be complete.

Soo... However, if the prime purpose is to create a totally free and
editable map of the world, we must then treat GeoBase with the same level of
indifference that we do to user:Acrosscanadatrails.  Just so happens that
there will be a few users who are importing the data, and have spent a real
long time gathering tracks and points, and converting the points into ways,
and labeling them, and is ready to start bringing in the data.

Just as user:Acrosscanadatrails did, when he started;  He didn't know how
this whole thing worked, and so he started adding in roads. .. and just had
it as highway=secondary, and highway=road for those ways that he didn't now.
... then he found out that having it as a secondary road, didn't quite match
what similar roads where in other towns, he changed it to
highway=residential, then someone else came along and changed the name from
James St. to James Street and HWY 4 to highway 4.

So the point is; Is that we can go ahead and start the import, working at it
1 tile at a time. And just learn as we go along. (use the chart and the talk
list to keep the discussion going)

(i use User:Acrosscanadatrails as the example for me importing geobase data)

So for the areas where User:Acrosscanadatrails did alot of gps tracks and
ways, and converted them to ways and points, and has it all sitting waiting
for the import.  Sadly :(  the work he did was for nothing.  :( as he found
out that a whole mapping team was just in the area and did it all already.
So user:Acrosscanadatrails, doesn't need to complain about it, as after all,
the GPS Tracks he did, DID get imported to the back-end database. ... and
all his points and ways he made got put aside and into the PostGIS database,
as after-all, he did take time to write the house numbers down.  But these
numbers just need to be converted to a point along side the road in the
center of where the house is, or real close or converted to a square, where
the 1 side is right on the road. .... but anyways.. after
all no renderer's can read his hand writing from his note paper  (BTW, I do
have bad hand writing :) ..) but he was smart enough to keep track of his
own numbers, so these numbers are listed with each point and way he made.


So after a while, when user:Acrosscanadatrails started to import roads; he
called them 'freeways' instead of 'moterways'. ... perhaps because
he's stubborn? and doesn't want to change his ways? ...
well fortunately Python script came along to help him translate and speak
OSM language. So the next tile import does the conversion already.

Fortunatly, user:Acrosscanadatrails  still keeps the cross reference number
he originally started with.  So now user:Bikecanada comes along and imports
more data. and imports it slightly different, and tags it differently. ..
but thats ok, because other users will come along and fix it to how it
should be.

So now user:Acrosscanadatrails went around a year later and added in more
roads (not thinking if any thing has been added) and goes around and just
takes note of all the new subdivisions that came up.   Well, he'll just to
what he did before... upload his traces to the database, and upload his
points and ways he made to the PostGIS database.  But this time, the script
which converts his previous imports is tweaked so it's much much smarter.
... However, because he knows where his reference points where, he can only
add on extra features that would not be added on otherwise. So... he needs
to only add in the house numbers, and not add in the actual road. (or he can
add in the road class/surface, but only if it hasn't been done)  As he knows
that there are other users who are around, and have already drawn in
cycleways, schools, parks in detail. as well as the local roads.

All of the roads that have been drawn in by hand, are well within the same
degree of accuracy (10 meters) as the roads that User:Acrosscanadatrails has
ready to upload, but he will be let down, :( as not only are his roads just
as good in accuracy, but the other users have actual GPS traces, to varify
the accuracy.    So all the user:Acrosscanadatrails can do to help is, add
in the Geodedic survay markers, and hope for better luck next time.

****

So here's the moral of the story:
GeoBase data importance:
1- the basic level is that contains unnamed lines
2- the lines have names but no road class
3- the lines have names, road class and house number
The GeoBase data, is just as smart as a new user, who needs to learn how to
import data and have it tagged so it conforms to OSM standards.  The
GeoBase doesn't have special privileges, and no longer 'Owns' the data that
it imports.  Anyone can edit it, and choose to not accept it.   ... the only
special thing that GeoBase has, is that it has reference numbers, and that
the data was imported into the PostGIS database (which is available only
behind the scenes, and contains both databases)
The technical aspect of the PostGIS database, isn't as important as
importing the data directly, it only becomes useful when it needs to figure
out what Geobase data is useful, so it can spit out only the good stuff.

So if these are the basic principles that we all can agreed to, we can move
forward to the next step of actual importing.

IMO, i would think it would be wise to weight a little longer, and hear from
other users, and what is the opinion of the rest of the OSM community, or at
least more interested people. so they get a chance to say something too.

We can then move on to the next step of actual import.

I propose that we start with tile 092F04 (Tofino, BC) as thats what i did,
and probably needs the basic script to get the road class right.
Or maybe 082E14 (Kelowna, BC)
or maybe the 030M04 (Hamilton, Stoney Creek, Ontario) but there is alot of
OSM coverage, so i think it would make sense to work with less OSM coverage
areas 1st... so to tweak the import script 1st. and to see what it's like
for fixing GeoBase data to conform with OSM standards.
... or even 001K10 & 001K11? (south of Saint Johns NFLD) and importing all
the kinds of data available for it?


And the last thought. ...
re: Ibycus topo
That was added as it's a convenient stop-gap measure, which helps, as there
is a very high probability that all the types of data that was imported to
make that map will show on OpenStreetMap eventually, as well as more data,
and even better data.
Once the actual import starts, i think it would make sense for people to be
downloading the map of the completed area, so to view it, and try to
understand all the kinds of data which is planned to be imported.
and i'm sure everyone knows that the stuff on his map CAN'T be imported
directly, and wont. .. as that doesn't make sense to do so.  (perhaps it
need to be written a bit clearer?)

Cheers,
Sam Vekemans
Across Canada Trails

---------- Forwarded message ----------
From: Richard Degelder <[EMAIL PROTECTED]>
Date: Fri, Dec 5, 2008 at 4:32 PM
Subject: Re: GeoBase PostGIS & OpenStreetMap
To: Sam Vekemans <[EMAIL PROTECTED]>


On Fri, 2008-12-05 at 15:25 -0800, Sam Vekemans wrote:
> Thanks,
> I also got 2 comments about the french name tagging, so i added it to
> the http://wiki.openstreetmap.org/wiki/Talk:GeoBase_Import page.
> And tried my best to translate this talk about PostGIS. :)
> Please edit, if you can :)
>
> The part about the stressing the importance of not undermining OSM
> contributions, needs to be highlighted more.  IMO
>

I looked at the wiki page and also at the map of Southern Ontario that
it pointed to as an example.  When I tried to display it the map was
offset from the general landforms, the map was a little south of the
representation of Lake Ontario and Lake Erie, but several things came to
mind immediately.  The first was "man do I ever want the import to work
and work soon."  There is a lot of detail in there that I want to have
in the OSM map as soon as possible.  There is also going to be some
reconfiguring of some of the roads.  There are roads with different
designations within the GeoBase map than I know they are rendered within
OSM.  But that is a minor technical detail that is really only a matter
of editing at some point.  The other impression was there are definitely
areas where OSM is way ahead of GeoBase and includes features that are
not available yet within the GeoBase data.  Yes I want to have GeoBase
assed to OSM but I also know that for some newer roads OSM is way ahead
of everyone else including GeoBase, Google maps, Yahoo! maps, and
everyone else.

>From what I have seen with the example I would love to have the area
around the western end of Lake Ontario imported soon with the knowledge
that there is going to have to be some cleanup done but that it looks
good and allows me to add some additional features to the area as well.
> and
> "Even if there is a single road
> through an area there has to be a way to for us to match it within
> both
> OSM and GeoBase.  "
> By using the charts we already started, and the name tags... we can
> create the set of rules that the PostGIS database import script will
> follow.   GeoBase Tag = OSM tag. .. and get as detailed as possable.
>

My prime reference is not going to be GeoBase, although it is certainly
an attempt to import the GeoBase data, but rather OSM.  We are
augmenting the current data within OSM with additional data from
GeoBase.  Regard GeoBase as a new contributor to OSM, just as you and I
each were at one time.  The whole project does not suddenly revolve
around a new contributor but they are allowed to augment, and that
includes editing and even deleting data, the data already within OSM.
GeoBase is just a new contributor that needs our help to edit the map
and to improve things within Canada.  Maybe GeoBase has an overwhelming
amount of knowledge at its disposal but it must conform to OSM rather
than OSM catering to it.  Sure, where there is the ability for the
GeoBase tags to augment the current tags within OSM for the data then
add the relevant tags.  And among those additions will be the GeoBase id
# for future references.  But where the tags conflict then we should go
with the OSM tags.  For one thing I am hoping that the OSM tags are
there because someone was on the ground there and saw the reason for the
tag before considering adding it.  Of course the person may not have
understood exactly what he or she was looking at and there are always
going to be discussions as how exactly to tag a feature, not that some
alternatives are necessarily wrong but what is the best way to do it.

> The realtime aspect (my last point on the talk) is still a little
> vague.
>
> Cheers,
> Sam

At this point we need to understand what the different people are
looking for the GeoBase import to accomplish.  For me it is to add
features to the OSM map that I am not likely to be able to do otherwise,
things like the hydro survey which would require me to access a lot of
private properties to do the survey.  If the prime purpose is to
complete the road network across Canada and doing so will cause issues
within OSM to accomplish that then I would recommend we abandon GeoBase
since we will eventually add all of the roads within Canada; it might
take a long time but it is doable with what we have available to us now.

By discussing what we want from the GeoBase import and how to go about
doing it at this point we can have a clearer understanding about what is
important and even if going forward is really worth it for the project.
And because GeoBase has so much detail we need to pick and choose what
we want to use for OSM.  And, within reason, the more we talk about it
the more likely we are to get it right as well.

Also I would recommend that you downplay any reference to Ibycus since
it is not going to be usable within OSM due to licensing issues since
they do not allow commercial usage of their maps.  With OSM we do not
have those restrictions and so importing data form Ibycus in any way,
even if indirectly, may eventually cause issues within OSM.  The dame
issues arise with people referring to Google maps as a source of data
for OSM, Google Maps has not given us permission, and licensed it, to
access their maps or satellite data for OSM.

Richard Degelder
rtdg
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