What is HDF5?

HDF5 (Hierarchical Data Format version 5) is a widely used file format designed for storing and managing large, complex datasets. It is commonly used in scientific computing, engineering, and research, especially when working with time series data, multidimensional arrays, or structured measurements collected over time.

HDF5 files organize data in a hierarchical structure, similar to a file system, where data is stored in groups and datasets. Each dataset can contain attributes - metadata that describes the data, such as units, descriptions, or sampling intervals.

HDF5 Support in Sigview

SIGVIEW provides native support for loading signal data directly from HDF5 files, making it easier to analyze scientific datasets without needing conversion or preprocessing.

What Data Can Be Loaded?

SIGVIEW automatically scans an HDF5 file for signal-like datasets - these are sequences of numerical values (e.g., time-domain signals, FFT outputs, etc.). All one-dimensional or signal-representable datasets can be loaded and analyzed.

Handling Sampling Rate and Metadata

Unlike some signal file formats, HDF5 does not define a standard way to store signal metadata such as Sampling rate and Units for time or amplitude.

To handle this, SIGVIEW looks for these values in a set of commonly used field names (attributes within the dataset). Examples of such fields include:

SamplingRate: "sampling_rate", "samplerate", "samplingrate", "sample_rate"

X-Unit = "x_axis", "xaxis", "XAxisUnit", "XAxis", "XUnits"

Y-Unit = "uni"t,"units", "Unit", "Units"

📌 Note: The list of recognized metadata fields is configurable. You can edit the file defaults.ini in your Application Data Folder to add or change field names SIGVIEW should look for when importing HDF5 datasets (under [HDF5] section).

If none of these values are found, SIGVIEW will use defaults (Sampling rate of 1.0, empty X/Y unit strings). These values can be changed afterwards by editing signal window properties.


Opening and Selecting Signals

When you open an HDF5 file in SIGVIEW:

The software scans the file and detects all datasets that represent signal-like sequences.

A selection dialog appears, showing a structured list of available signals:

You can browse the list and choose which signals to load into your workspace for analysis.

This interface allows you to load exactly the data you need while preserving the HDF5 structure for clarity.