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GeoPDF is a line of map and imagery products created by TerraGo software applications. GeoPDF products use geospatial PDF as a container for maps, imagery, and other data used to deliver an enhanced user experience in TerraGo applications. However, GeoPDF products conform to published specifications including both the OGC best practice for PDF georegistration as well as Adobe's proposed geospatial extensions to ISO 32000, making them readable by applications such as Adobe Acrobat, Adobe Reader, Avenza PDF Maps, Global Mapper, and others.
GeoPDF products often include other advanced PDF features such as layers and object data which can add significant GIS functionality to the file, particularly when used with the TerraGo Technologies plugin to Adobe Reader or other TerraGo clients.
GeoPDF products are used to deliver maps and imagery from multiple US government agencies. Quadrangles of The National Map are available from the USGS store in as GeoPDF products and are free to download. The US Army Corps of Engineers distributes GeoPDF maps through the U.S. Army Corps of Engineers Topographic Engineering Center. These include Country DVDs of standard National Geospatial-Intelligence Agency (NGA) maps.
The GeoPDF trademark should not be confused with georeferencing techniques such as the OGC best practice or Adobe's geospatial extensions to ISO 32000 or with geospatial PDF files in general. Nothing about the georeferencing metadata in a GeoPDF product is proprietary; these metadata are embedded in conformance with published specifications and best practices. GeoPDF is best thought of as a branded instance of geospatial PDF.
Portable Document Format (PDF), standardized as ISO 32000, is a file format developed by Adobe in 1992 to present documents, including text formatting and images, in a manner independent of application software, hardware, and operating systems. Based on the PostScript language, each PDF file encapsulates a complete description of a fixed-layout flat document, including the text, fonts, vector graphics, raster images and other information needed to display it. PDF has its roots in "The Camelot Project" initiated by Adobe co-founder John Warnock in 1991. PDF was standardized as ISO 32000 in 2008. The last edition as ISO 32000-2:2020 was published in December 2020.
The Geography Markup Language (GML) is the XML grammar defined by the Open Geospatial Consortium (OGC) to express geographical features. GML serves as a modeling language for geographic systems as well as an open interchange format for geographic transactions on the Internet. Key to GML's utility is its ability to integrate all forms of geographic information, including not only conventional "vector" or discrete objects, but coverages and sensor data.
A coverage is the digital representation of some spatio-temporal phenomenon. ISO 19123 provides the definition:
A GIS file format is a standard for encoding geographical information into a computer file, as a specialized type of file format for use in geographic information systems (GIS) and other geospatial applications. Since the 1970s, dozens of formats have been created based on various data models for various purposes. They have been created by government mapping agencies, GIS software vendors, standards bodies such as the Open Geospatial Consortium, informal user communities, and even individual developers.
GeoTIFF is a public domain metadata standard which allows georeferencing information to be embedded within a TIFF file. The potential additional information includes map projection, coordinate systems, ellipsoids, 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.
The National Map is a collaborative effort of the United States Geological Survey (USGS) and other federal, state, and local agencies to improve and deliver topographic information for the United States. The purpose of the effort is to provide "...a seamless, continuously maintained set of public domain geographic base information that will serve as a foundation for integrating, sharing, and using other data easily and consistently".
A GIS software program is a computer program to support the use of a geographic information system, providing the ability to create, store, manage, query, analyze, and visualize geographic data, that is, data representing phenomena for which location is important. The GIS software industry encompasses a broad range of commercial and open-source products that provide some or all of these capabilities within various information technology architectures.
ISO/TC 211 is a standard technical committee formed within ISO, tasked with covering the areas of digital geographic information and geomatics. It is responsible for preparation of a series of International Standards and Technical Specifications numbered in the number range starting at ISO-19101. The Chair of the committee was 1994-2016: Olaf Østensen; during 2017-2018: Christina Wasström; and from 2019 Agneta Gren Engberg.
Catalogue Service for the Web (CSW), sometimes seen as Catalogue Service - Web, is a standard for exposing a catalogue of geospatial records in XML on the Internet. The catalogue is made up of records that describe geospatial data, geospatial services, and related resources.
The Geospatial Data Abstraction Library (GDAL) is a computer software library for reading and writing raster and vector geospatial data formats, and is released under the permissive X/MIT style free software license by the Open Source Geospatial Foundation. As a library, it presents a single abstract data model to the calling application for all supported formats. It may also be built with a variety of useful command line interface utilities for data translation and processing. Projections and transformations are supported by the PROJ library.
Geospatial metadata is a type of metadata applicable to geographic data and information. Such objects may be stored in a geographic information system (GIS) or may simply be documents, data-sets, images or other objects, services, or related items that exist in some other native environment but whose features may be appropriate to describe in a (geographic) metadata catalog.
PDF/UA, formally ISO 14289, is an International Organization for Standardization (ISO) standard for accessible PDF technology. A technical specification intended for developers implementing PDF writing and processing software, PDF/UA provides definitive terms and requirements for accessibility in PDF documents and applications. For those equipped with appropriate software, conformance with PDF/UA ensures accessibility for people with disabilities who use assistive technology such as screen readers, screen magnifiers, joysticks and other technologies to navigate and read electronic content.
The Open Geospatial Consortium Web Coverage Service Interface Standard (WCS) defines Web-based retrieval of coverages – that is, digital geospatial information representing space/time-varying phenomena.
Geospatial PDF is a set of geospatial extensions to the Portable Document Format (PDF) 1.7 specification to include information that relates a region in the document page to a region in physical space — called georeferencing. A geospatial PDF can contain geometry such as points, lines, and polygons. These, for example, could represent building locations, road networks and city boundaries, respectively. The georeferencing metadata for geospatial PDF is most commonly encoded in one of two ways: the OGC best practice; and as Adobe's proposed geospatial extensions to ISO 32000. The specifications also allow geometry to have attributes, such as a name or identifying type.
GeoAPI is free software providing a set of Java interfaces for GIS applications. GeoAPI interfaces are derived from the abstract model and concrete specifications published collaboratively by the International Organization for Standardization (ISO) in its 19100 series of documents and the Open Geospatial Consortium (OGC) in its abstract and implementation specifications. GeoAPI provides an interpretation and adaptation of these standards to match the constraints and usages of the target programming language. The international standards translated to Java interfaces are:
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 1994 and involves more than 500 commercial, governmental, nonprofit and research organizations in a consensus process encouraging development and implementation of open standards.
TerraGo is a private company based in Sterling, Virginia with offices in Atlanta, Georgia, and the UK that develops location intelligence, geospatial collaboration, GIS applications, GPS data collection software. Founded in 2005, TerraGo is an In-Q-Tel portfolio company. In 2012, TerraGo acquired fellow In-Q-Tel portfolio company Geosemble. Aside from being an In-Q-Tel portfolio company, TerraGo is notable in part for pioneering the patented technology, related standards and best practices upon which GeoPDF and geospatial PDF are based and programs related thereto.
GeoSUR is a regional initiative led by spatial data producers in Latin America and the Caribbean to implement a regional geospatial network and to help establish the basis of a spatial data infrastructure in the region. GeoSUR supports the development of free access geographic services useful to find, view and analyze spatial information through maps, satellite images, and geographic data.
GeoPackage (GPKG) is an open, non-proprietary, platform-independent and standards-based data format for geographic information systems built as a set of conventions over a SQLite database. Defined by the Open Geospatial Consortium (OGC) with the backing of the US military and published in 2014, GeoPackage has seen widespread support from various government, commercial, and open source organizations.
The Portable Document Format (PDF) was created by Adobe Systems, introduced at the Windows and OS/2 Conference in January 1993 and remained a proprietary format until it was released as an open standard in 2008. Since then, it has been under the control of an International Organization for Standardization (ISO) committee of industry experts.