[Talk-ca] Talk-ca Digest, Vol 10, Issue 1

[Steve Singer]

On Tue, 2 Dec 2008, Richard Degelder wrote:

> Can we give the duplicates, the OSM data that is already there, the
> attributes of the GeoBase data so that in the future any updates treat
> the already present OSM features as if they were originally GeoBase
> data?

This is something that I think is worthy of more effort.

IF we can take an existing OSM way and say that it 'essentially' the same as 
a geobase entity we can then:

1. Add some of the geobase tags to the data
2. Have a basis for dealing with conflicting data that is finer than a 
bounding box.

Even for cities that are 'well mapped' we mostly don't have street numbering 
and geobase is starting to provide this for more parts of the country.  We 
don't be able to superimpose street numbers onto existing OSM streets unless 
we've added the geobase node ids.

Have any of the other import projects tried to do this?

One option might be to import the OSM data and geobase into a spatial 
database (PostGIS?) and then find all 'OSM streets that are within x 
distance of the a geobase street that where both run in the same direction' 
you could even try to compare the 'name' of the streets.   This could 
produce a mapping of OSM to geobase nodes.  This type of 'guessing' won't be 
100% accurate or complete but might get us closer to our end goal than 
excluding existing well mapped areas from the import.

> Richard Degelder
> rtdg
>

Steve