Barcelona Parcel Import

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About

This project's goal is to change the current buildings into parcels due to how they are structured. Currently the building are marked as a whole instead of small buildings next to each other.

Import Plan Outline

Goals

Merge the official data source of CartoBCN into OSM.

Schedule

The import will happen during the weekends of the last week of November and the first week of December

Import Data

Background

Provide links to your sources.

Data source site: http://w20.bcn.cat/cartobcn/default.aspx?lang=en
Data license: http://w24.bcn.cat/geoportal/descargas/cond_us_carto.pdf
Type of license (if applicable): CC-BY 3.0
OSM attribution (if required): https://wiki.openstreetmap.org/wiki/Contributors#Barcelona_City_Council_.28CartoBCN.29
ODbL Compliance verified: yes

OSM Data Files

The file used for the import is: barna.osm.bz2

Import Type

The import is a One Time import as the users can add or remove buildings later.

The tools used will be QuantumGIS for the osm file preparation and JOSM for the actual importing

Data Preparation

Data Reduction & Simplification

Since the original files contain a LOT of redundant points just to define a line MapSharper will be used with a setting of ~33% to simplify the shapefiles.

More so, internal tags only used by the Barcelona City Council will be removed leaving just the street address and number.

Tagging Plans

The shapefile attributes will be replaced with another data source of the same page containing address info of the street level address using QuantumGIS and area merge. The remaining tags after all the cleanup will be:


Tag Description Example
LPost_I/F This tag may or may not exist on the shape. It contains an additional address number field: the letter A,A
NPost_I/F Contains the first and last numbers of the building. 220, 224
N_CarrerC Contains the street name Trav de Gràcia
T_Via Contains the type of street Trav
Desc_Via Contains the full street type Travessera

This will be corrected to the correct tags in OSM

Tag Formula
addr:street N_CarrerC with T_Via string replaced using Desc_Via
addr:housenumber NPost_I, NPost_F + LPost_I, LPost_F

As a matter of simplifying the import we will add building=yes manually

Changeset Tags

Tags used will be: Continue Importing Barcelona

Data Transformation

No more transformations will be required

Data Transformation Results

The resulting osm file will be the one provided above

Data Merge Workflow

Team Approach

I'll be doing this solo. Reviewing the data quickly so SOME things may escape my attention

References

Factors taken into account will be parks and places were some similar work has happened

Workflow

  • First we will remove all the buildings that are just blocks without any kind of tag just building=yes
  • Add the replacement shapes and tag them with building=yes
  • Try and locate places were some conflation will have to happen such as parks and named buildings
  • Merge the tags
  • Upload to OSM

The changeset size will vary greatly with no fixed limit apart from how much data we can download from OSM at a time.

Revert plans are to use the Reverter plugin in JOSM if it's too big and manual correction if small

Conflation

The approach to conflation will be copying the tags from the object being overwritten and adding them to the replacement object.

If it's a park, area or similar the building tag will be removed

In case of not knowing what to do we will leave the old object instead of removing so that someone at a later time can decide what to do with it