BEGIN:VCALENDAR VERSION:2.0 PRODID:-//pretalx//talks.osgeo.org//foss4g-2023//JMVJMS BEGIN:VTIMEZONE TZID:CET BEGIN:STANDARD DTSTART:20001029T040000 RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10 TZNAME:CET TZOFFSETFROM:+0200 TZOFFSETTO:+0100 END:STANDARD BEGIN:DAYLIGHT DTSTART:20000326T030000 RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=3 TZNAME:CEST TZOFFSETFROM:+0100 TZOFFSETTO:+0200 END:DAYLIGHT END:VTIMEZONE BEGIN:VEVENT UID:pretalx-foss4g-2023-LPDRTF@talks.osgeo.org DTSTART;TZID=CET:20230629T160000 DTEND;TZID=CET:20230629T163000 DESCRIPTION:The collection\, curation and publication of geospatial informa tion has been for centuries the sole prerogative of public sector organisa tions. Such data has been traditionally considered the reference source fo r datasets and cartographic outputs. However\, new geospatial data sources (e.g. from the private sector and citizen-generated[1]) have emerged that are currently challenging the role of the public sector [2]. In response to this\, governments are currently exploring new ways of managing the cre ation and update of their geospatial datasets [3]. \nDatasets of high rele vance are increasingly produced by both private companies and crowdsourced initiatives. E.g.\, in 2022 Microsoft released Microsoft Building Footpri nts\, a dataset of around 1 billion building footprints extracted from Bin g Maps imagery from 2014 to 2022. More recently\, in December 2022n Amazon Web Services (AWS)\, Meta\, Microsoft\, and TomTom founded the Overture M aps Foundation (https://www.linuxfoundation.org/press/linux-foundation-ann ounces-overture-maps-foundation-to-build-interoperable-open-map-data)\, a joint initiative in partnership with the Linux Foundation with the aim to curate and release worldwide map data from the aggregation of multiple inp ut sources including civic organisations and open data sources\, especiall y OpenStreetMap data.\nThese initiatives aim to improve the coverage of ex isting governmental geospatial information through the release of open dat a and a strong dependency on OpenStreetMap. In particular\, the Overture initiative has the explicit goal to add quality checks\, data integration\ , and alignment of schemas to OSM data.\nRecently\, the Italian Military G eographic Institute (IGM\, one of the governmental mapping agencies in Ita ly) has released a multi-layer dataset called “Database di Sintesi Nazio nale” (DBSN\, https://www.igmi.org/en/dbsn-database-di-sintesi-nazionale ). The DBSN is intended to include geospatial information relevant to anal ysis and representation at the national level\, with the additional purpos e to derive maps at the scale 1:25\,000 through automatic procedures. The creation of the DBSN builds on top of various information sources\, with r egional geotopographic data as primary source of information and products from other national public bodies (e.g. cadastral maps) as additional sour ces. The source is recorded in a specific attribute field for each feature in the database\, with a list of codes referencing the various sources. A mong the external sources used as input for the work of integration in the DBSN\, OpenStreetMap was explicitly considered and used.\nOne of the elem ents of novelty\, at least in the Italian context\, is the release of the DBSN under the ODbL licence (https://opendatacommons.org/licenses/odbl)\, caused by the fact that the inclusion of OSM data requires derivative prod ucts to be released with the same licence.\nCurrently\, the DBSN includes data covering only 12 out of the 20 Italian regions (Abruzzo\, Basilicata\ , Calabria\, Campania\, Lazio\, Marche\, Molise\, Puglia\, Sardegna\, Sici lia\, Toscana\, Umbria). The remaining ones will be released in the near f uture.\nThe datasets have been downloaded from the official IGM website in January 2023.\nThe DBSN schema is a subset of the specifications defined in the "Catalogue of Spatial Data - Content Specifications for Geotopograp hic Databases” (Decrete 10 November 2011) and is composed of 10 layers\, 29 themes and 91 classes. We compared it with the OpenStreetMap specifica tions (based on the community-based tagging scheme at https://wiki.openstr eetmap.org/wiki/Map_Features) and selected two main themes (buildings and streets).\nThe analysis was performed through a set of Python scripts avai lable under the open source WTFPL licence at https://github.com/napo/dbsno smcompare.\nFirstly\, we analysed—for buildings and streets in the IGM d atabase—where OSM data was used as the primary source of information. Th e percentage of buildings derived from OSM is minimal\, ranging from 0.01% in Umbria to 1.3% in Marche\; regarding streets\, the differences between regions increase\, ranging from almost 0% in Abruzzo and Calabria to 94% in Umbria.\nSecondly\, we calculated the area covered by buildings and the length of streets in both the IGM and OSM databases to understand how muc h OSM completeness is good\, compared to the official IGM dataset.\nIn the 12 regions\, the area covered by buildings in OSM is on average about 55% of the corresponding area in IGM\, while the percentage of the length of streets is about 78%. Anyway\, these numbers are highly variable among reg ions\, ranging between 32% in Calabria and 105% in Puglia for buildings\, and between 46% in Calabria and 103% in Umbria for streets.\nThese first r esults show that the main source information in the DBSN (namely the offic ial regional data) is highly variable across the 12 regions\, which requir ed the IGM to find additional data sources to fill the gaps. OSM plays a m inor role for integrating buildings in the database\, while it demonstrate s a high potential for contributing to street information.\nResults also s how that\, even with only a small contribution\, some elements that are pr esent in OSM are still not included in the DBSN. This can be due to at lea st two reasons: (i) the current workflow of selection of elements in OSM ( through tags) does not include some potentially relevant elements\; ii) th e (ideally) daily update of OSM is able to bring in the database new featu res at a pace that is unbeatable by the IGM\, and governmental organisatio ns in general.\nWhile this study highlights the importance that OpenStreet Map has achieved as a reference source of geospatial information for gover nmental bodies as well\, providing evidence of its contribution to the nat ional database of the IGM\, iit also paves the way for improving OpenStree tMap itself by importing data for various layers\, benefiting from the rel ease of the DBSN under the ODbL licence. DTSTAMP:20260316T151529Z LOCATION:UBT E / N209 - Floor 3 SUMMARY:OpenStreetMap as an input source for producing governmental dataset s: the case of the Italian Military Geographic Institute - Marco Minghini\ , Alessandro Sarretta URL:https://talks.osgeo.org/foss4g-2023/talk/LPDRTF/ END:VEVENT END:VCALENDAR