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Welcome to the PH5 wiki.

This wiki contains information on requirements, installation instructions, usage, as well as the underlying structure of PH5. To get started using PH5 please see the wiki page on Creating, Validating, and Archiving a PH5 experiment.

What is PH5

PH5 is the PASSCAL Instrument Center recommended archival format for active, passive, and mixed source seismological data sets. PASSCAL has transitioned to PH5, PASSCAL's implementation of the Hierarchical Data Format, version 5 (HDF5) data model, as the preferred archival format.

A PH5 experiment is built using multiple HDF5 files. A full archive contains a master.ph5 file and a number of miniPH5_#####.ph5 files. The master.ph5 file stores the metadata as well as links to the miniPH5_#####.ph5 files. The actual time series data is stored in miniPH5_#####.ph5.

PH5 is a unified archiving format designed to make archival and retrieval of data as simple as possible. PH5's architecture also allows for quick editing of experiment metadata. This is because metadata is separated from the rest of the data allowing the metadata data to be updated and edited without having to reprocess the entire dataset.

Why HDF5?

The strengths of HDF5 make it an attractive model for an active source archival data format:

Extensible and portable, allowing it to evolve and operate on a variety of platforms through a number of programming interfaces
Self describing and allows direct access to parts of the file without the need to parse the entire file
Has been in use for two decades and is utilized in a variety of disciplines, from aerospace to the medical field.