GeoTIFF (Georeferenced TIFF)
Open BetaGeoTIFF és un format ràster amb georeferenciació incrustada. El mapa es desa com a imatge TIFF amb coordenades, projecció i metadades. L'estàndard de facto per als mapes ràster georeferenciats.
Característiques clau
Sobre el format GeoTIFF
GeoTIFF is an ordinary TIFF with coordinates written into its tags: where the top left corner lies, what the pixel size is and which coordinate system all of it is recorded in. A GIS program opens such a file and immediately puts the picture in its place on the ground — there is nothing to georeference by hand.
A raster map is needed where vectors are excessive or awkward: an underlay beneath your own layers, a print-ready original, an overlay on a satellite image, material for interpretation and for raster algorithms.
The file contains a map page drawn in the chosen style and saved as a georeferenced image. The default resolution is 300 DPI, that is print quality; the default sheet is A4 landscape. LZW compression is lossless, yet noticeably smaller than an uncompressed TIFF.
The default coordinate system is WGS84 (EPSG:4326); the georeferencing sits in the file's own tags, so there is no need to keep any companion files alongside it.
Quin programa obre els fitxers GeoTIFF
Els programes i les aplicacions següents poden obrir, editar i treballar amb fitxers GeoTIFF (Georeferenced TIFF) (.tif) exportats des d'OSM2CDR:
Format specifications
- Open standard
- 2D only
- Lossless (no quality loss)
- No attributes
- Output: 1 file
- GeoTIFF (OGC) with georeferencing tags. Single .tif file; default LZW compression. Standard for GIS raster.
Qui utilitza els mapes GeoTIFF
Com exportar GeoTIFF
Com obrir el fitxer després de l'exportació
- QGIS (free) — drag the .tif into the program window: the layer lands in place and the projection is detected automatically.
- ArcGIS and Global Mapper — Add Data; the raster attaches as an underlay beneath your vector layers.
- Google Earth Pro — File → Import, choose the GeoTIFF: the map lands on the globe (for heavy files the program will offer to reduce the resolution).
- GDAL — gdalinfo map.tif shows the georeferencing and the projection, and gdalwarp -t_srs EPSG:3857 map.tif out.tif reprojects the raster for a web map.
- Printing — the file is calculated for 300 DPI and goes to print as is; in Photoshop or GIMP do not change the pixel dimensions, otherwise you will lose both quality and the match to the scale.
Mapes populars en GeoTIFF
Obtingues exportacions de mapes GeoTIFF (Georeferenced TIFF)
Descarrega mapes GeoTIFF professionals d'OpenStreetMap. Generació instantània, qualsevol àrea.
Preguntes freqüents
Compara amb altres formats
Formats relacionats
Sovint exportats junts
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