Prepared by: Emily Porter

Last revised: Feb 2018

Status: Final Draft for Approval

Technical/Characterization Metadata

Overview

Technical/characterization metadata provides information about the characteristics and composition of a digital file (such as its size, mime type, compression, and encoding information), and is an important component of digital preservation. Technical metadata is only applicable to digital file assets (i.e. PCDM Files), not intellectual objects (i.e. PCDM Objects).

The DLP Metadata Implementation Working Group (M-IWG) analyzed characterization metadata separately from other types of preservation metadata because it is primarily auto-extracted from a file by means of tools such as JHOVE, FITS, or MediaInfo, as opposed to being manually created by a content curator. Additional preservation-related metadata are documented separately based on requirements identified by the Digital Preservation Functional Requirements Group.

While most significant to preservation curators, some technical metadata properties may also be useful to present to end-users about how to interact with the file (duration, size, file type, filename, etc.) and to understand the context in which it was originally created. 

The following elements are recommended as baseline technical metadata for both generic and specific formats (analogous to Emory Primary Content Types), based upon a review of Samvera community metadata standards, Emory stakeholder-supplied fields, and Samvera’s primary technical file characterization tool, FITS, as well as the utilization of FITS data as incorporated into the HydraWorks characterization software (see Appendices A and B). In 2016, a number of test cases were evaluated against FITS (see Appendix B) against available versions of FITS.

Indexing and display recommendations are also noted below for selected metadata units, based on feedback from the Metadata Implementation Working Group and additional stakeholders from the Digitization and Digital Curation team provided in 2016. The tables that follow indicate where having system actionable (searchable, viewable) technical metadata may be useful, as opposed to characterization metadata remaining in a static text/XML file which may be included as part of an archival package. The properties listed are based on FITS 1.2, but the version implemented for the DLP repository is configurable based on versions supported by Samvera software[PE1] .

See also - Merged Spreadsheet/Inventory View

Baseline Generic Technical Metadata

The following properties are recommended for alltypes of digital files, regardless of format. Note: common digital file properties may also be expressed/stored as Preservation metadata (PREMIS object characteristics). 

* Indicated in Samvera Technical Metadata Profile and/or HydraWorks Characterization Profile

**Indicated in PREMIS standard (digital object characteristics)

*** Addressed elsewhere in MIWG specifications

Baseline for Audio 

*Listed in HydraWorks, but not in current FITS specification

Baseline for Video