Aerial orthophotography 2017-2018 on Rennes Métropole

Description

It is an orthorectified vertical aerial view of the territory of Rennes Métropole. Orthorectification consists of distorting the image in order to correct the deformations inherent in the relief. If the buildings are not orthorectified (canopy can mask the immediate environment of high buildings), this is the case for works of art or superstructures related to the road. a more complete description of an orthophotography can be found in a document attached to the metadata. \- Projection used for data acquisition: Lambert 93/IGN69 \- Deliverables delivered in RGF93-CC48 \- Planimetric accuracy class of data: 20 cm (2 pixels) \- Native resolution: 10 cm \- Recovery: 80 %-80 % on an East-West band covering the whole of Rennes and 65 %-65 % on the rest of metropolitan territory \- Delivery in the form of 1 km x 1 km tiles and in the form of a single slab \- Syntax used for naming tiles: XXXX_YYYY, from the X-Y coordinates in RGF93-CC48 \- Shooting dates: due to the bad weather conditions encountered during the period conducive to aerial photography in 2017, only the south of the agglomeration could not be covered. The entire northern part of the territory was acquired in the summer of 2018. Because aerial shooting has not been continuous over time, colorimetric differences are visible. Following the availability of aerial orthophotography slabs on the rest of the Ille-et-Vilaine department (resolution 20 cm entirely realised in 2017), the 2017-2018 orthophotography data of the metropolitan territory have been supplemented by slabs of departmental orthophotography to cover the territory outside Rennes Métropole and form a rectangular right-of-way. This dataset consists of 893 slabs of 1 km x 1 km for a volume of about 33 GB in the format JPEG 2000 (JP2) for resolution 10 cm. A map showing the entire flooring, the year of shooting of the slabs and the name of the slabs is annexed to the metadata. For internal uses within the City of Rennes and Rennes Métropole, in order to facilitate its use on GIS tools (ArcGIS and QGIS); a single multi-scale slab in JPG2000 (JP2) format has been created. The full ownership of orthophotography 2017-2018 belongs to the trade union Mégalis Bretagne and all local authorities in Brittany. The 10 cm slabs in JP2 format on the territory of Rennes Métropole are individually downloadable on the Open Data site of Rennes Métropole. To read the JP2 format in Photoshop, a plugin is required (for example: https://www.web3.lu/photoshop-plugins-jpeg-ls-jpeg-xr-jpeg-2000/). For performance issues, it is advisable to use, in descending order of priority (and depending on the software possibilities): 1\. cached services/WMTS or TMS tiles services of GeoWebCache 2\. the GeoWebCache WMS service 3\. GeoServer’s WMS service

Resources

Name Format Description Link
57 https://www.data.gouv.fr/api/1/datasets/r/5448cf6d-20a1-4934-b307-a4d808c08773
23 https://www.data.gouv.fr/api/1/datasets/r/767686fd-cc4c-4791-94b3-50eda96ab16c
23 https://www.data.gouv.fr/api/1/datasets/r/86ebce1f-380c-4fda-9a7d-3015c1f24f51
8 https://www.data.gouv.fr/api/1/datasets/r/beb61845-2ecc-41b0-a0dc-0b75e202a870

Tags

  • photographie
  • referentiels-geographiques
  • photographie-aerienne

Topics

Categories