2019 FOSS4G Bucharest Talks speaker: Even Rouault
Revamp of Coordinate Reference System management in the OSGeo C/C++ stack with PROJ and GDAL
In this talk, we will give an overview of the recent works that have occurred in the PROJ, libgeotiff and GDAL libraries regarding Coordinate Reference Systems (CRS). Those improvements have mostly taken place in the venerable PROJ library that has evolved over the last 30 years from handling “only” more than hundred of cartographic projections to becoming a full-fledged library for CRS management and transformations.
PROJ 6 now supports OGC and ISO standards regarding object modeling (ISO-19111 / OGC Abstract topic 2), and their Well-Known Text representation (OGC WKT1, WKT2:2015 and latest WKT2:2018). A sqlite3-based database embeds the definitions coming from various authorities: EPSG, IGN-France and the ESRI projection engine. PROJ can now compute optimal and more accurate transformations between two CRS without necessarily using the ill-defined WGS84 pivot (“late-binding”), and support new CRS and transformations.
We will discuss the the adoption status of PROJ 6 by the rest of the OSGeo stack and present quickly how to migrate to this new version.
State of GDAL
After a brief introduction to the project, this talk will focus on the two feature-oriented releases which have occurred during the last year, GDAL 2.4 and GDAL 3.0.
We will explore new drivers (Google Earth Engine Data API, NextGIS Web, GeoJSON sequence, TileDB, ...), improved drivers (BAG, GeoTIFF with Lerc and WebP codecs, Geospatial PDF generation…), improved algorithms (polygonal contouring), new virtual file systems, the integration of PROJ 6 and its benefits (genuine database with definitions of coordinate reference systems and coordinate operations, support for WKT 2, late-binding transformations)
The advance of community efforts that have lead to a revamped Python testing suite and documentation/web site will also be presented.