hdf images hdf images

HDF4-to-HDF5 NOAA SDS Project

This project has been completed.
How can the long-term archival of data be achieved without maintaining multiple versions of multiple I/O libraries?

This one-year research project, funded by NOAA Climate Program Office(CPO) Scientific Data Stewardship(SDS), provides a solution to migrate data to a single standards-based archive format. Specifically, we will investigate on how to store NASA ECS data and metadata into HDF5 Archival Information Packages (AIP). To achieve this, the HDF4 to HDF5 conversion tool has been enhanced so that converted ECS data can be read through the NetCDF4 interface. In addition, metadata tools will be developed for converting ECS collection and granule level metadata to NOAA's collection level by following NARA's METS standard.

May 2008 saw the 2.0 release of the HDF4 to HDF5 conversion tool. This release includes new functionality as the converted ECS data can be read through the NetCDF4 interface. Information for the release can be found at http://www.hdfgroup.org/h4toh5/

We have tested 33 typical HDF-EOS2 products at the National Snow and Ice Data Center (NSIDC) that include EOS swath, grid and point files. Figure 1A shows monthly rainfall in July 2007 over land based on a AMSR EOS2 file. Figure 1B shows the same field converted to an HDF5 file with the enhanced HDF4 to HDF5 conversion tool. The fact that Figure 1A and Figure 1B are the same reflects that the enhanced conversion tool works correctly.

Figure 1A
Figure 1A

Figure 1B
Figure 1B

This project is included in H4H5TOOLS 2.0 (or higher). To enable the enhancement provided by this project, H4H5TOOLS requires the following:

Useful links

Many HDF-EOS2 files are available at the NSIDC external. ftp site. We downloaded 47 files from various subdirectories. These 47 files contain all three kinds of HDF-EOS2 data types: Grid, Swath, and Point. Among the 33 Grid data files we received, five different projection codes were used.

HDFView is a visual tool for browsing and editing HDF4 and HDF5 files.

HDFView HDF-EOS Plug-in external is a plugin for HDFView. This plugin allows users to browse HDF-EOS objects and attributes.

netCDF-4 external is the latest netCDF package. netCDF-4 can generate and read HDF5 files. HDF4-to-HDF5 utility can generate HDF5 files that can be read by netCDF-4.

NCAR Command Language external is an interpret language for scientific data. This tool can be used to draw charts from HDF-EOS2 files and netCDF files.

- - Last modified: 28 October 2013