GeoTIFF is a public domain metadata standard that enables georeferencing information to be embedded within an image file. The GeoTIFF format embeds geospatial metadata into image files such as aerial photography, satellite imagery, and digitized maps so that they can be used in GIS applications.
What is GeoTIFF?
A GeoTIFF file extension contains geographic metadata that describes the actual location in space that each pixel in an image represents. In creating a GeoTIFF file, spatial information is included in the .tif file as embedded tags, which can include raster image metadata such as:
- horizontal and vertical datums
- spatial extent, i.e. the area that the dataset covers
- the coordinate reference system (CRS) used to store the data
- spatial resolution, measured in the number of independent pixel values per unit length
- the number of layers in the .tif file
- ellipsoids and geoids - estimated models of the Earth’s shape
- mathematical rules for map projection to transform data for a three-dimensional space into a two-dimensional display
Dr. Niles Ritter originally developed the GeoTIFF file format for NASA and published “GeoTIFF Revision 1.0” in 2000. In 2019 the Open Geospatial Consortium published OGC GeoTIFF standard, which outlines standardized GeoTIFF specifications and encoding rules for using the Tagged Image File Format (TIFF) for the exchange of georeferenced or geocoded imagery.
The “Cloud Optimized GeoTIFF” standard was developed in 2016 within the Open Source Geospatial Foundation/GDAL (OSGF) project as a format that is easily accessible with the use of common geographic software tools such as GDAL, GeoTrellis, and QGIS.
In 2020 Digital Elevation Models, a 3D computer graphics representation of elevation data in Earth, moon, or asteroid terrains, were migrated to the Cloud Optimized GeoTIFF data delivery format, which supports ever evolving cloud processing capabilities.
The OSGF licensed permissive X/MIT style free software, under which was released the Geospatial Data Abstraction Library (GDAL) computer software library for reading and writing raster and vector geospatial data formats. Google supplies some of their data in COG format, and users can easily download GeoTIFFs from Google Earth Engine.
There is a variety of proprietary and open source GeoTIFF viewers for accessing and displaying GeoTIFF format images. Creating GeoTIFF maps with these software solutions can be as easy as drag-and-drop. The GeoTIFF file is simply uploaded into the online program, followed by input of the spatial reference system, map format and sizing selection, then the map is rendered using the input spatial reference.
Geodata is drawn from vector formats on a map, and the geodata is converted to the specified output projection of the map if the projection in the source file differs. Some of the vector and raster formats typically supported by a GeoTIFF online viewer include: asc, gml, gpx, json, kml, kmz, mid, mif, osm, tif, tab, map, id, dat, gdbtable, and gdbtablx.
Does OmniSci Offer a Solution for Embedded Geospatial Data?
Billions of records of location-rich geodata, embedded into image files via GeoTIFF formatting, are generated continuously, providing enormous value to a variety of geospatial applications. Geographic Information Systems store, analyze, and use this geographic metadata to create layered maps to better understand everything from complex environmental events to socioeconomic trends.
The OmniSciDB SQL engine natively stores geometric and geodata types, enabling geo calculations with the massively parallel processing power of CPUs and GPUs. OmniSci Immerse visualization system’s powerful cross-filtering and zero-latency exploration of big geodata helps Geospatial analysts better understand and prepare the dataset for further use.