[Imports] Spanish cadastre

[David Marín Carreño]

El 22 de marzo de 2012 20:38, Paul Norman <penorman at mac.com> escribió:
>
> > From: Carlos Dávila [mailto:cdavilam at orangecorreo.es]
> > Sent: Thursday, March 22, 2012 5:28 AM
> > To: imports at openstreetmap.org
> > Subject: [Imports] Spanish cadastre
> >
> > Data from Spanish Cadastre is known to have a high accuracy and include
> > a lot of information of interest for OSM project, such as buildings
> > (shape, use, height, number of floors, etc.), rural and urban parcels
> > land use, most of streets and roads of the country, power stations,
> > tracks and paths, trees... Many of this information is currently in OSM,
> > mainly ways and roads, but a great part is still missing, specially in
> > low populated areas where a ground survey is less likely to be made.
> > This import has been largely discussed on Spanish mailing list, with a
> > general consensus on the usefulness of the import and a "we must do it"
> > agreement.
>
> What is your proposed tagging of these objects?
>
> Cadastre generally have a lot of detailed information, not all of which is
> suitable for importing into OSM. Which datasets do you intend to import and
> which do you intend to leave out?
>

The Spanish community has selected which objects are going to be
imported, and how they will be tagged, using OSM wiki[1] (sorry, in
Spanish).

>
> > Specific accounts have been created for the import, one for each Spanish
> > province. There's a member of the Spanish community responsible of
> > each province import.
>
> What software do you plan to use to conflate with existing OSM data?

JOSM (or other editor).

> How do you intend to upload the data?

Cadastre data is available for each municipality, and must be
downloaded manually.

So, a collaborator will download Cadastre data for a municipality, and
then will transform this data into OSM format using the new Cat2Osm
tool. After that, using JOSM (or other editor), he will do the final
checks and corrections before uploading it to OSM using the created
account.

> Approximately how large will the changesets be?
>

The current testing version of Cat2OSM is generating (for example) for
"Puebla de Don Fadrique (Granada)"[2]:
* 188177 nodes
* 48421 ways
* 19839 relations

For "Alcobendas (Madrid)"[3]:
* 350092 nodes
* 183413 ways
* 67179 relations

Although this amounts will vary, as Cat2Osm is still being refined and
corrected.


>
> I suggest breaking your import proposal into sub-proposals for each type of
> data set. E.g. have a different proposal for roads than for buildings.
>

Road imports would be exceptional (only in villages without previous
OSM mapping), as the road data in Spanish Cadastre requires a lot of
manual corrections before being imported into OSM.

Cat2Osm currently imports, among other data:
* rural and urban parcels and subparcels, with their landuse (see [1])
* type of crop in the case of farmlands, detailed at subparcel level
* addr:housenumber and addr:street for urban parcels
* buildings with their heights (if a building has different heights,
this will be shown in the data, so this data could be used for 3d
rendering)

[1] http://wiki.openstreetmap.org/w/index.php?title=Traduccion_metadatos_catastro_a_map_features
[2] http://en.wikipedia.org/wiki/Puebla_de_Don_Fadrique
[3] http://en.wikipedia.org/wiki/Alcobendas

Best regards,
--
David Marín Carreño <davefx at gmail.com>