Representing digital assets usingMPEG-21 Digital Item Declaration

Abstract

Various XML-based approaches aimed at representing compound digital assets have emerged over the last several years. Approaches that are of specific relevance to the digital library community include the Metadata Encoding and Transmission Standard (METS), the IMS Content Packaging XML Binding, and the XML Formatted Data Units (XFDU) developed by CCSDS Panel 2. The MPEG-21 Digital Item Declaration (MPEG-21 DID) is another standard specifying the representation of digital assets in XML that, so far, has received little attention in the digital library community. This artic le gives a brief insight into the MPEG-21 standardization effort, highlights the major characteristics of the MPEG-21 DID Abstract Model, and describes the MPEG-21 Digital Item Declaration Language (MPEG-21 DIDL), an XML syntax for the representation of digital assets based on the MPEG-21 DID Abstract Model. Also, it briefly demonstrates the potential relevance of MPEG-21 DID to the digital library community by describ ing its use in the aDORe repository environment at the Research Library of the Los Alamos National Laboratory (LANL) for the representation of digital assets.

A standard‐based context sensitive service architecture for digital object dissemination

“…Due to the requester definition, it is only natural to define the Referent Rntity within the same standard framework, namely the MPEG-21 DID (ISO, 2003). This is not only the favored descriptor from a previous comparison (De Sutter, Notebaert, & Van de Walle, 2006), but has been shown to be very suitable for digital object description in digital repositories Bekaert, Kooning, & Sompel, 2006). The ServiceType Entity also needs further customization in this architecture to reflect the various services provided.…”

The aDORe federation architecture: digital repositories at scale

“…A Digital Object is the perspective of a repository's native compound digital object that is shared with an aDORe federation. The aDORe federation architecture allows for a choice of serialization formats such as DIDL [6,10], METS [33], or ORE Atom [26]. Use of the same format across a federation is handy yet not essential.…”

“…This led to direct involvement in the MPEG-21 standardization effort, in particular in the parts Digital Item Declaration [10], Digital Item Declaration Language and Digital Item Identification [11], a suite of papers describing the thinking with this regard [2,6], and the release of the DIDLTools, a Java toolkit for manipulating serializations of compound objects compliant with the MPEG-21 DID data model [31].…”

Generating best-effort preservation metadata for web resources at time of dissemination

“…The Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH) offers a solution to this dilemma since it supports complex object types such as METS and MPEG-21 DIDL [2]. We can use this format as a container, or CRATE, for our preservation-prepared resource.…”