Veneto/Guide e documentazione/About CTR Veneto Import

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This page describes the organization behind the import of data from "Carta Tecnica Regionale" of Veneto region (Italy).

Info

Wiki pages:

Technical

  • The data imported mainly regards buildings and vegetation. In some less frequent cases there have been imported also landuses (mainly residential and industrial) and barriers delimiting buildings' areas (fences).
  • Data are reprojected with Quantum GIS, converted with shp-to-osm, fixed and imported with JOSM.
  • Data are given "cut" in square by the source, of the size of a small town. This helps the import of small areas. Mappers who import data are aware that an object, for example a building, must be merged with its half if this falls in a nearby square. Some users merge them before uploading the new data to the map, some others upload the buildings cut in half and then merge them in a second changeset.
  • The number of squares in which data are given by the source is very high, one for each row of this table. In that page each mapper who imports some data should write what data he imported by writing "Sì" on a column, just to keep a memory of what/where data was imported.

History

  • Some mappers started importing data from this source in 2010 by themselves. At the end of that year a mapper put on the Wiki a first draft of a guide to uniform import procedure and to agree on a tagging scheme after discussing them on the Italian mailing list. During 2011 another mapper created and put on the Wiki the new, official guide for the import and the official tagging scheme, by refining the tags of the old draft and by adding new tags that better fitted the objects that had to be imported. His work has been announced and discussed in the regional and national mailing lists. Another example of a thread on the national mailing list regarding projections.
  • In Spetember 2011 a small group of mappers who met at OSMit launched the initiative of the import of buildings of the most populated cities of the region. The project, called "OSMVeneto Import Day", consisted in a collaboration among many local mappers so that each mapper could import buildings of the area where he lives. Till now there have been 5 import days, the last one in February 2012. The most populated areas are mostly imported by now. During those days mappers coordinate with each other on the regional mailing list regarding the date of the import, the areas and the procedure (the official guide and tagging scheme). After each import: statistics were made about the import, errors and necessary reverts were discussed, and the tagging scheme was refined.
  • Now, mappers who want to import data for the remaining less populated zones do that by themselves, but still using the same guide and tagging scheme.

Pros

  • Data are not imported by one people for all the region but from many mappers (more than 20 by now), who usually live in the zone they import.
  • Mappers follow the same guide and the same tagging scheme, discussed before in the national and regional mailing lists.
  • The import increased the number of discussions of the regional mailing list regarding mapping techniques, tagging and errors fixing.

Cons

  • The quality of the import depends on the care and the attention which every mapper puts in the import of his zone.
  • Some areas have been imported with more care than others, so somewhere there are still some errors to be fixed (for example duplicate nodes and self-intersecting ways).