HDF5 Structure

The HDF5 library serves as the backbone of the NDE file format. The .nde format uses the HDF5 library along with the data model defined in this documentation to provide a consistent, flexible, and powerful format for the NDT industry.

As the .nde format inherits the hierarchical characteristic of the HDF5 framework, its data model can be represented as a tree structure similar to a file system structure with folders and files. Within the HDF5 framework, folders are called groups and files are called datasets.

Each .nde file should follow this basic structure:

Tip

Click on the Private, Public, Setup, Groups, or Properties blocks to learn more. 

flowchart LR
  .nde[**.nde**]:::root --> Private["/Private"]:::group
  .nde[**.nde**]:::root --> Public["/Public `required`"]:::group
  .nde[**.nde**]:::root --> Properties["/Properties*"]:::dataset
  Public["/Public*"] --> Setup["/Setup*"]:::dataset
  Public["/Public*"] --> Groups["/Groups"]:::group
  .nde@{ shape: text}
  click Public "public-group"
  click Private "private-group"
  click Properties "../json-metadata/properties"
  click Setup "../json-metadata/setup"
  click Groups "public-group#groups-group-and-subgroups"
  classDef root fill:#fff
  classDef group fill:#ffc72c,stroke:#000000,color:#000000
  classDef dataset fill:#fff,stroke:#000000,color:#000000

Each of the structure layers represents either an HDF5 group (yellow rectangle) or a dataset (white rectangle). Mandatory groups and datasets are highlighted by a * at the end of their name.

Any .nde file can be opened using a regular HDF5 reader such as HDFView or MyHDF5, allowing you to explore its structure and get a glance at its content. Learn more by exploring some of our example files.

MyHDF5