GeoTIFF is a
public domain
The public domain (PD) consists of all the creative work to which no exclusive intellectual property rights apply. Those rights may have expired, been forfeited, expressly waived, or may be inapplicable. Because those rights have expired, ...
metadata standard which allows
georeferencing Georeferencing means that the internal coordinate system of a map or aerial photo image can be related to a geographic coordinate system. The relevant coordinate transforms are typically stored within the image file (GeoPDF and GeoTIFF are examples ...
information to be embedded within a
TIFF
Tag Image File Format, abbreviated TIFF or TIF, is an image file format for storing raster graphics images, popular among graphic artists, the publishing industry, and photographers. TIFF is widely supported by scanning, faxing, word processin ...
file. The potential additional information includes
map projection
In cartography, map projection is the term used to describe a broad set of transformations employed to represent the two-dimensional curved surface of a globe on a plane. In a map projection, coordinates, often expressed as latitude and longit ...
,
coordinate systems,
ellipsoid
An ellipsoid is a surface that may be obtained from a sphere by deforming it by means of directional scalings, or more generally, of an affine transformation.
An ellipsoid is a quadric surface; that is, a surface that may be defined as the ...
s,
datums, and everything else necessary to establish the exact spatial reference for the file. The GeoTIFF format is fully compliant with TIFF 6.0, so software incapable of reading and interpreting the specialized metadata will still be able to open a GeoTIFF format file.
An alternative to the "inlined" TIFF geospatial metadata is the
*.tfw World File sidecar file format which may sit in the same folder as the regular TIFF file to provide a subset of the functionality of the standard GeoTIFF described here.
History
The GeoTIFF format was originally created by Dr. Niles Ritter while he was working at the
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeedi ...
Jet Propulsion Laboratory
The Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center in the City of La Cañada Flintridge, California, United States.
Founded in the 1930s by Caltech researchers, JPL is owned by NASA ...
. The
reference implementation
In the software development process, a reference implementation (or, less frequently, sample implementation or model implementation) is a program that implements all requirements from a corresponding specification. The reference implementation ...
code was released mostly as
public domain software with some parts under a
permissive X license
The MIT License is a permissive free software license originating at the Massachusetts Institute of Technology (MIT) in the late 1980s. As a permissive license, it puts only very limited restriction on reuse and has, therefore, high license com ...
. On September 14, 2019, the
Open Geospatial Consortium
The Open Geospatial Consortium (OGC), an international voluntary consensus standards organization for geospatial content and location-based services, sensor web and Internet of Things, GIS data processing and data sharing. It originated in 199 ...
published the OGC GeoTIFF standard, which defines the Geographic Tagged Image File Format (GeoTIFF) by specifying requirements and encoding rules for using the Tagged Image File Format (TIFF) for the exchange of georeferenced or geocoded imagery. The OGC GeoTIFF 1.1 standard formalizes the existing community GeoTIFF specification version 1.0 and aligns it with the continuing addition of data to the EPSG Geodetic Parameter Dataset.
Cloud Optimized GeoTIFF
"Cloud Optimized GeoTIFF" (COG) is a standard based on GeoTIFF, designed to make it straightforward to use GeoTIFFs hosted on
HTTP
The Hypertext Transfer Protocol (HTTP) is an application layer protocol in the Internet protocol suite model for distributed, collaborative, hypermedia information systems. HTTP is the foundation of data communication for the World Wide Web, ...
webservers, so that users and software can make use of partial data within the file without having to download the entire file.
[Cloud Optimized GeoTIFF website]
/ref>[COG technical specification (on Github)]
/ref> It is designed to work with HTTP range requests, and specifies a particular layout of data and metadata within the GeoTIFF, such that clients can predict which range of bytes they need to download. COG is simply a specialisation of GeoTIFF, so COG files are TIFF files.
The pattern of optimizing GeoTIFFs for HTTP range requests was first demonstrated at large scale when AWS
Amazon Web Services, Inc. (AWS) is a subsidiary of Amazon that provides on-demand cloud computing platforms and APIs to individuals, companies, and governments, on a metered pay-as-you-go basis. These cloud computing web services provide di ...
started hosting Landsat
The Landsat program is the longest-running enterprise for acquisition of satellite imagery of Earth. It is a joint NASA / USGS program. On 23 July 1972, the Earth Resources Technology Satellite was launched. This was eventually renamed to L ...
data on Amazon S3 in 2015. The pattern was developed into the COG within the Open Source Geospatial Foundation
The Open Source Geospatial Foundation (OSGeo), is a non-profit non-governmental organization whose mission is to support and promote the collaborative development of open geospatial technologies and data. The foundation was formed in February 20 ...
/GDAL
The Geospatial Data Abstraction Library (GDAL) is a computer software library for reading and writing raster and vector geospatial data formats (e.g. shapefile), and is released under the permissive X/MIT style free software license by the O ...
project, starting in around 2016. The COG format can be read and written by many common geographic software tools including GDAL
The Geospatial Data Abstraction Library (GDAL) is a computer software library for reading and writing raster and vector geospatial data formats (e.g. shapefile), and is released under the permissive X/MIT style free software license by the O ...
, QGIS, and GeoTrellis.[Chris Holmes (2018), "Cloud Optimized GeoTIFF Advances"]
/ref> Various providers now supply some of their data in COG format, including USGS
The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, ...
, NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeedi ...
, Google
Google LLC () is an American Multinational corporation, multinational technology company focusing on Search Engine, search engine technology, online advertising, cloud computing, software, computer software, quantum computing, e-commerce, ar ...
and DigitalGlobe.DigitalGlobe blog: Cloud optimized GeoTIFFs and the path to accessible satellite imagery analytics
/ref>
See also
* Digital raster graphic
A digital raster graphic (DRG) is a digital image resulting from scanning a paper USGS topographic map for use on a computer. DRGs created by USGS are typically scanned at 250 dpi and saved as a TIFF. The raster image usually includes the origi ...
* GDAL
The Geospatial Data Abstraction Library (GDAL) is a computer software library for reading and writing raster and vector geospatial data formats (e.g. shapefile), and is released under the permissive X/MIT style free software license by the O ...
- Open source GeoTIFF reader and writer
* Tagged Image File Format (TIFF)
* The *.tfw World File
References
External links
OGC GeoTIFF
formalizes the existing community GeoTIFF specification version 1.0 and aligns it with the continuing addition of data to the EPSG Geodetic Parameter Dataset.
GeoTIFF.io
Open-source website for viewing and analyzing GeoTIFF files
*
* {{cite web , url= http://www.geospatialworld.net/article/geotiff-a-standard-image-file-format-for-gis-applications/ , title= GeoTIFF - A standard image file format for GIS applications , publisher= Geospatial World , date= Sep 1, 2009 , quote= Details backwards compatible GeoTIFF extensions to the TIFF file format and header
Cartography
GIS file formats
GIS raster file formats
Public-domain software with source code
Free software
Raster graphics file formats