HDF5 provides a flexible, extensible, and efficient data model, programming interface, and storage model for keeping and managing spatial data.

15 June 2020: The Open Geospatial Consortium (OGC) membership has approved the Hierarchical Data Format Version 5 (HDF5) Core as an official OGC Standard.

Hierarchical Data Format Version 5 (HDF5) is a data model, a programming interface, and a storage model for keeping and managing data. HDF5 supports an unlimited variety of data types, and is designed to be flexible and efficient for large and complex data. Due to its use of customizable data types, HDF5 is extensible, allowing communities and their applications to evolve the use and functionality of HDF5.

HDF5 provides an encoding standard particularly suitable to scientific and engineering geospatial applications that employ complex multidimensional datasets to describe phenomena that change over time and/or space. 

“We are excited that OGC has chosen HDF5 as one of its prescribed standards to support its ongoing mission to create free and publicly available geospatial standards. One of the challenges scientists and other users face when using a data technology is that different communities and applications have inconsistent understandings of the precise meanings of the digital objects those technologies work with. This can lead to misunderstandings, to incorrect results, and ultimately to flawed science and decisions. By working with the HDF Group to define the OGC HDF5 Core standard, OGC has created a rigorous, unambiguous, definition of what HDF5 is. This critical contribution helps to ensure that geospatial data stored in HDF5 will be relevant to the OGC’s community now and into the future,” commented Mike Folk, Interim CEO of The HDF Group.

HDF5 is designed to be simple yet versatile. HDF5 is capable of supporting complex data relationships and dependencies through its grouping and linking mechanisms. Additionally, HDF5 is self-describing through its accommodation of user-defined metadata.

The OGC HDF5 Core standard defines the HDF5 data model to allow implementers to develop HDF5 content and tools using the HDF5 or other storage models and programming interfaces. 

HDF5 is already in use by the OGC community: OGC’s NetCDF Enhanced Data Model ( OGC 11-038r2) can be fully described by the HDF5 data model because its storage format is also HDF5. However, the HDF5 data model includes several entities whose features go significantly beyond those of the NetCDF Enhanced model. 

Furthermore, OGC members are using HDF5 as a standard format for more complex data types. In particular, HDF5 has been proposed as at least two standards for point cloud data in the OGC Point Cloud Domain Working Group, and has been demonstrated as a GDAL compliant format for images ( KEA). HDF5 is also used as an open standard for other geographic data, such as the Bathymetric Attributed Grid (BAG) format, which is the basis for the International Hydrographic Organization’s standards.

The HDF5 data format and library was created, and is maintained, by the HDF Group. The group’s mission is to ensure long-term access to data stored in HDF5 and support its dedicated and diverse user community. The organization actively partners with users to understand their needs and challenges and to help them use HDF5 effectively. As a long-time OGC member, The HDF Group actively contributes to numerous standards activities. The HDF Group chairs OGC's HDF Standards Working Group, where the conceptual model was developed.

As with any OGC standard, the open Hierarchical Data Format Version 5 (HDF5) Core standard is free to download and implement. Interested parties can view and download the standard from OGC’s Hierarchical Data Format Version 5 (HDF5) Core Standard Page.

About The HDF Group
The HDF Group (HDF) is a non-profit organization with the mission of advancing state-of-the-art open source data management technologies, ensuring long-term access to the data, and supporting its dedicated and diverse user community. HDF does this by ensuring the creation of high-quality software that addresses user needs and takes advantage of innovations in data management. In addition, HDF is the developer and maintainer of HDF5®, a high-performance software library and data format that has been adopted across multiple industries and is the de facto standard in the scientific and research community. Please visit hdfgroup.org for more information.

About OGC
The Open Geospatial Consortium (OGC) is an international consortium of more than 500 businesses, government agencies, research organizations, and universities driven to make geospatial (location) information and services FAIR - Findable, Accessible, Interoperable, and Reusable.
OGC’s member-driven consensus process creates royalty free, publicly available geospatial standards. Existing at the cutting edge, OGC actively analyzes and anticipates emerging tech trends, and runs an agile, collaborative Research and Development (R&D) lab that builds and tests innovative prototype solutions to members' use cases.
OGC members together form a global forum of experts and communities that use location to connect people with technology and improve decision-making at all levels. OGC is committed to creating a sustainable future for us, our children, and future generations.
Visit ogc.org for more info on our work.