Digital Preservation Matters - 04 April 2008

Audio and Video Carriers: Recording Principles, Storage and Handling, Maintenance of Equipment, Format and Equipment Obsolescence. Dietrich Schuller. TAPE. February 2008.

This is an introduction to those working with sound and video collections. It outlines the history of various types of audio recordings, including CD and DVDs, how they were made and how stable they are. Also an overview of the passive preservation factors, particularly environment, handling and storage. Humidity and oxidation affect the physical surfaces. Other factors are dust, pollution, light, and magnetic fields. It includes a section on the maintenance of equipment and the obsolescence of formats.

IMLS Will Sponsor Second Conservation Forum for Collecting Institutions. Jill Collins. IMLS. Press Release. March 20, 2008.

This forum “Collaboration in the Digital Age” is intended to help museums and libraries think strategically about digital preservation. It is to be held June 24-25 in Denver. It will emphasized the fundamentals of digital content creation and preservation, emphasizing practical approaches to planning digital projects, increasing access to collections, enabling digital resources to serve multiple purposes, and protecting digital investments. In 2006, online visits accounted for 310 million of the 1.2 billion adult visits to museums and 560 million of the 1.3 billion adult visits to libraries. Yet 60% of collecting institutions do not include digital preservation in their mission.

Audio Tape Digitisation Workflow: Digitisation Workflow for Analogue Open Reel Tapes. Juha Henriksson, Nadja Wallaszkovits. TAPE. March 2008.

A practical web-based workflow for audio tape digitization. Looks at physical factors, such as tape problems, equipment, and conversion. The standard CD sampling rate of 44.1 kHz is outdated and may be inadequate for many types of material. Currently 96 kHz is regarded as a widely accepted standard. IASA recommends a minimum sampling rate of 48 kHz, though some types of material may need 192 kHz. They also recommend an encoding rate of at least 24 bit to capture analog items. Other topics are metadata, recording level, format, and archival masters. After digitization the digital file is now the preservation format. For preservation purposes an asset register should be kept and updated, and should also record the checksum for each file.

White Paper: Representation Information Registries. Adrian Brown. PLANETS. 29 January 2008.

A report on Representation Information Registries. These are a critical component of digital preservation architecture, containing the technical knowledge necessary to support access to digital objects. “Any meaningful digital preservation activity requires some form of knowledge base regarding the technical environments necessary to support access to digital objects.” This is expressed in the OAIS model. Key reasons for the registries are: efficiency of description; knowledge sharing; sustainability. “Preservation planning encompasses all activities which identify the need to perform preservation actions, and the most appropriate actions to perform in order to meet specified objectives.”

Developing Practical Approaches to Active Preservation. Adrian Brown. National Archives, UK. June 2007.

The active preservation methodology comprises three main functions:

1. characterization: measures the properties of digital objects needed for long-term preservation;
2. preservation planning: the appropriate preservation actions to be undertaken; and
3. preservation action: the results of preservation planning, transforming the objects

The PRONOM technical registry supports these functions and is the core of the preservation system. The preservation planning framework determines what preservation actions should be applied to which objects, and the appropriate time to apply them.