High Resolution Aerial Photography [ORTHO® HR - IGN-F] - Department of Calvados - 2023

The 2023 ORTHO® HR (High Resolution Orthophotography) is a collection of digital mosaics of colour orthophotography, rectified in the specific legal projection adapted to the territory covered. ORTHO® HR 2023 is freely distributed under an open licence thanks to the financial support of the European Union and the Normandy Region. It is requested that all studies carried out from this database include the mention given produced with the support of Europe and the Normandy Region within the framework of the Normandy CRIGE.” The 2023 ORTHO® HR offers many advantages: - Spatial planning: land use, land consumption and new communication routes; - environment: coastal and forest observatory, bocage management; - Communication: visualization of the evolution of the territory. **Collection context** The original files distributed by the IGN on https://geoservices.ign.fr/documentation/diffusion/telechargement-donnees-libres.html#ortho-hr-sub-licence-opened under Open License are: - in legal projection (Lambert 93 in mainland France and other specific projection for each French overseas department) - in JPEG2000 “lossless” format per 1km x 1km slab - compressed as a 7z archive (long to decompress for marginal compression gain, slabs already compressed) In order to facilitate the use of the tiles composing the HR 2023 orthophoto, we also offer a pyramid in GeoPackage OGC format in lambert 93. **Collection method** The Geopakage was produced from the GDAL library: ``` gdalbuildvrt D:\8_Ortho_2023\2023.vrt -addalpha -srcnodata 255 -hidenodata D:\8_Ortho_2023\data\*.jp2 gdalwarp D:\8_Ortho_2023\2023.vrt D:\8_Ortho_2023\2023.gpkg -t_srs EPSG:2154 -r cubic -of GPKG gdaladdo -r cubic D:\8_Ortho_2023\2023.gpkg 4 16 64 256 ```