The NetCDF Expansion Pack (NEP) extends the netCDF C library with lossless compression filters and User-Defined Format (UDF) readers, so existing C, Fortran, and Python software can read new scientific and imaging formats without code changes.
Scientific data is often locked in specialized file formats that require custom parsers, brittle conversion pipelines, and duplicated tooling. Researchers waste time writing format-specific readers instead of doing science.
NEP builds on two extension points already present in netCDF-C:
Because NEP exposes foreign formats as ordinary netCDF datasets, existing analysis tools, visualization pipelines, and AI/ML workflows can work with DICOM images, protein structures, GRIB2 weather grids, and planetary data without custom parsers. New read-only or read-write readers can be added for additional formats.
NEP is built and maintained by our Senior Engineer, a co-author of the netCDF C/Fortran/C++ libraries and former GRIB/BUFR libraries team lead at NOAA.
nc_open()NEP extends the netCDF C library with User-Defined Format (UDF) readers and additional compression filters, so existing netCDF applications can open new scientific and imaging formats without code changes.
Open DICOM, PDB/mmCIF, GRIB2, and other formats through the netCDF API your existing tools already use.
LZ4, BZIP2, and LibPressio-integrated filters reduce storage size without losing information.
Feed imaging, weather, and structural-biology data directly into analysis and machine-learning pipelines.
Explore supported formats, see working examples, or reach out for integration support.