ISO/IEC 21000-2:2005

Information technology — Multimedia framework (MPEG-21) — Part 2: Digital Item Declaration

ISO/IEC 21000-2:2005 specifies: Model: The Digital Item Declaration Model describes a set of abstract terms and concepts to form a useful model for defining Digital Items. Representation: The Digital Item Declaration Language (DIDL) is based upon the terms and concepts defined in the above model. It contains the normative description of the syntax and semantics of each of the DIDL elements, as represented in XML. Schema: Informative XML schemas illustrating complete grammars for representation of the DID in XML conforming to the normative representation. Detailed Examples: Illustrative (non-normative) examples of DIDL documents are provided to aid in understanding the use of the specification and its potential applications. The ISO/IEC 21000 (MPEG-21) series of International Standards defines an open framework for multimedia delivery and consumption, with both the content creator and content consumer as focal points. The vision for MPEG-21 is to define a multimedia framework to enable transparent and augmented use of multimedia resources across a wide range of networks and devices used by different communities. This second part of MPEG-21 (ISO/IEC 21000-2:2005) specifies a uniform and flexible abstraction and interoperable representation for declaring the structure and makeup of Digital Items. A Digital Item Declaration (DID) involves specifying the resources, metadata, and their interrelationships for a Digital Item. A DID is done using the Digital Item Declaration Language (DIDL).

Technologies de l'information — Cadre multimédia (MPEG-21) — Partie 2: Déclaration d'article numérique

General Information

• Status: Published
• Publication Date: 05-Oct-2005
• ICS: 35.040 - Information coding
• ICS: 35.040.40 - Coding of audio, video, multimedia and hypermedia information
• Technical Committee: ISO/IEC JTC 1/SC 29 - Coding of audio, picture, multimedia and hypermedia information
• Drafting Committee: ISO/IEC JTC 1/SC 29 - Coding of audio, picture, multimedia and hypermedia information
• Current Stage: 9093 - International Standard confirmed
• Completion Date: 11-Oct-2019

Relations

• Amended By: ISO/IEC 21000-2:2005/Amd 1:2012 - Information technology — Multimedia framework (MPEG-21) — Part 2: Digital Item Declaration — Amendment 1: Presentation of digital item
• Effective Date: 18-Dec-2021
• Revises: ISO/IEC 21000-2:2003 - Information technology — Multimedia framework (MPEG-21) — Part 2: Digital Item Declaration
• Effective Date: 15-Apr-2008
• Consolidated By: ISO 21029-2:2015 - Cryogenic vessels — Transportable vacuum insulated vessels of not more than 1 000 litres volume — Part 2: Operational requirements
• Effective Date: 06-Jun-2022

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 21000-2
Second edition
2005-10-01


Information technology — Multimedia
framework (MPEG-21) —
Part 2:
Digital Item Declaration
Technologies de l'information — Cadre multimédia (MPEG-21) —
Partie 2: Déclaration d'article numérique





Reference number
ISO/IEC 21000-2:2005(E)
©
ISO/IEC 2005

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ISO/IEC 21000-2:2005(E)
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©  ISO/IEC 2005
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
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ISO/IEC 21000-2:2005(E)
Contents Page
Foreword. v
Introduction . vi
1 Scope. 1
2 Normative references. 1
3 Terms and definitions. 2
4 Symbols and abbreviated terms . 2
5 Conventions . 3
5.1 Naming convention. 3
5.2 Documentation convention . 3
5.3 Namespace prefix conventions. 5
6 Digital Item Declaration Model . 6
6.1 Purpose and Overview . 6
6.2 Abstract Model. 6
6.2.1 Entity Descriptions . 6
6.2.2 container. 6
6.2.3 item. 6
6.2.4 component. 7
6.2.5 anchor . 7
6.2.6 descriptor . 7
6.2.7 condition. 7
6.2.8 choice. 8
6.2.9 selection . 8
6.2.10 annotation. 8
6.2.11 assertion . 8
6.2.12 resource. 8
6.2.13 fragment. 8
6.2.14 statement . 8
6.2.15 predicate . 8
7 Digital Item Declaration Representation. 10
7.1 Purpose and Overview . 10
7.1.1 Purpose. 10
7.1.2 DIDL Overview. 10
7.2 DIDL Definition . 11
7.2.1 Validation. 11
7.2.2 Canonicalization . 11
7.2.3 Document modularity. 11
7.2.4 Element Descriptions . 12
7.2.5 . 12
7.2.6 . 14
7.2.7 . 15
7.2.8 . 15
7.2.9 . 17
7.2.10 . 20
7.2.11 . 22
7.2.12 . 25
7.2.13 . 27
7.2.14 . 31
7.2.15 . 34
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ISO/IEC 21000-2:2005(E)
7.2.16 . 37
7.2.17 . 38
7.2.18 . 41
7.2.19 . 42
7.2.20 . 45
8 The Digital Item Declaration XML Schema Definitions (informative). 46
8.1 Purpose and Overview . 46
8.2 DID Model Abstract Schema . 47
8.3 DIDL Schema. 49
9 Example Digital Items expressed in DIDL . 57
9.1 Example 1: Using MPEG-7 descriptors in conjunction with a Choice. 57
9.2 Example 2: Expressing the same set of metadata in different descriptor formats. 59
9.3 Example 3: A digital music album. 60
9.4 Example 4: Implementing numeric comparisons in Item configuration . 78
Annex A (informative) Patent statements . 81
Annex B (informative) Differences with ISO/IEC 21000-2:2003. 82
B.1 Introduction . 82
B.2 Attribute-based descriptors. 82
B.3 . 82
B.4 . 82
B.5 and . 83
B.6 . 83
B.7 and XInclude. 83
B.8 Schema definitions . 85
B.9 Converting a first edition DIDL document to a second edition DIDL document . 86
Bibliography . 88

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ISO/IEC 21000-2:2005(E)
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members of
ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with particular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest. Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote.
ISO/IEC 21000-2 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 29, Coding of audio, picture, multimedia and hypermedia information.
This second edition cancels and replaces the first edition (ISO/IEC 21000-2:2003), which has been technically
revised.
ISO/IEC 21000 consists of the following parts, under the general title Information technology — Multimedia
framework (MPEG-21):
⎯ Part 1: Vision, Technologies and Strategy [Technical Report]
⎯ Part 2: Digital Item Declaration
⎯ Part 3: Digital Item Identification
⎯ Part 5: Rights Expression Language
⎯ Part 6: Rights Data Dictionary
⎯ Part 7: Digital Item Adaptation
⎯ Part 8: Reference Software
⎯ Part 9: File Format
⎯ Part 10: Digital Item Processing
⎯ Part 11: Evaluation Tools for Persistent Association Technologies [Technical Report]
⎯ Part 12: Test Bed for MPEG-21 Resource Delivery [Technical Report]
⎯ Part 15: Event Reporting
⎯ Part 16: Binary Format
The following parts are under preparation:
⎯ Part 4: Intellectual Property Management and Protection Components
⎯ Part 14: Conformance Testing
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ISO/IEC 21000-2:2005(E)
Introduction
Today, many elements exist to build an infrastructure for the delivery and consumption of multimedia content.
There is, however, no “big picture” to describe how these elements, either in existence or under development,
relate to each other. The aim for MPEG-21 is to describe how these various elements fit together. Where gaps
exist, MPEG-21 will recommend which new standards are required. ISO/IEC JTC 1/SC 29/WG 11 (MPEG) will
then develop new standards as appropriate while other relevant standards may be developed by other bodies.
These specifications will be integrated into the multimedia framework through collaboration between MPEG
and these bodies.
The result is an open framework for multimedia delivery and consumption, with both the content creator and
content consumer as focal points. This open framework provides content creators and service providers with
equal opportunities in the MPEG-21 enabled open market. This will also be to the benefit of the content
consumer providing them access to a large variety of content in an interoperable manner.
The vision for MPEG-21 is to define a multimedia framework to enable transparent and augmented use of
multimedia resources across a wide range of networks and devices used by different communities.
This second part of MPEG-21 (ISO/IEC 21000-2) specifies the mechanism for declaring the structure and
makeup of Digital Items.
The International Organization for Standardization (ISO) and International Electrotechnical Commission (IEC)
draw attention to the fact that it is claimed that compliance with this document may involve the use of a patent.
The ISO and IEC take no position concerning the evidence, validity and scope of this patent right.
The holder of this patent right has assured the ISO and IEC that he is willing to negotiate licences under
reasonable and non-discriminatory terms and conditions with applicants throughout the world. In this respect,
the statement of the holder of this patent right is registered with the ISO and IEC. Information may be obtained
from the companies listed in Annex A.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights other than those identified in Annex A. ISO and IEC shall not be held responsible for identifying any or
all such patent rights.
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INTERNATIONAL STANDARD ISO/IEC 21000-2:2005(E)

Information technology — Multimedia framework (MPEG-21) —
Part 2:
Digital Item Declaration
1 Scope
This document describes the ISO/IEC 21000 Digital Item Declaration technology, which is Part 2 of the
ISO/IEC 21000 series of International Standards. It specifies:
⎯ the Digital Item Declaration Model (see 6),
⎯ the Digital Item Declaration Representation in XML (see 7), and
⎯ XML schemas comprising grammars for the Digital Item Declaration representation in XML (see 8).
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO/IEC 21000 (all parts), Information Technology — Multimedia Framework (MPEG-21)
IETF RFC 2045, Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies,
IETF Request for Comments: 2045, November 1996
IETF RFC 2616, Hypertext Transfer Protocol – HTTP/1.1, IETF Request for Comments: 2616, June 1999
IETF RFC 3548, The Base16, Base32, and Base64 Data Encodings, IETF Request for Comments: 3548,
July 2003
IETF RFC 3986, Uniform Resource Identifier (URI): Generic Syntax, IETF Request For Comments: 3986,
January 2005
W3C XINCLUDE, XML Inclusions (XInclude) Version 1.0, W3C Recommendation, 20 December 2004
W3C XML, Extensible Markup Language 1.0 (Second Edition), W3C Recommendation, 6 October 2000
W3C XMLC14N, Canonical XML Version 1.0, W3C Recommendation, 15 March 2001
W3C XMLNAMES, Namespaces in XML, W3C Recommendation, 14 January 1999
W3C XMLSCHEMA, XML Schema Part 1: Structures Second Edition and XML Schema Part 2: Datatypes
Second Edition, W3C Recommendations, 28 October 2004
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ISO/IEC 21000-2:2005(E)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
Abstraction
distinct intellectual or artistic creation or concept
[ISO/IEC TR 21000-1:2004]
3.2
Asset
Manifestation, i.e. physical or digital embodiment of an Expression
[ISO/IEC TR 21000-1:2004]
3.3
Digital Item
a structured digital object with a standard representation, identification and metadata within the MPEG-21
framework
NOTE This entity is the fundamental unit of distribution and transaction within the MPEG-21 framework as a whole; it
has, however, no further technical meaning. Within this document (part 2 of MPEG-21: Digital Item Declaration), an item is
a grouping of sub-items and/or components that are bound to relevant descriptors, as defined within the Digital Item
Declaration Model (see 6). The term item is a technical term, and is, as such, a narrower term than Digital Item. In
conclusion, the use of the two different terms Digital Item and item within MPEG-21 is consistent and intended.
3.4
Expression
intellectual or artistic realisation of an Abstraction
[ISO/IEC TR 21000-1:2004]
3.5
Manifestation
the physical or digital embodiment of an Expression
[ISO/IEC TR 21000-1:2004]
4 Symbols and abbreviated terms
For the purposes of this document, the following abbreviations apply.
DID: Digital Item Declaration
DIDL: Digital Item Declaration Language
EBNF: Extended Backus-Naur Form
IANA:  Internet Assigned Numbers Authority
IETF:  Internet Engineering Task Force
IPMP: Intellectual Property Management and Protection
JPEG:  Joint Photographic Experts Group
MIME:  Multipurpose Internet Mail Extensions (IETF RFC 2045)
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ISO/IEC 21000-2:2005(E)
MPEG:  Moving Picture Experts Group
MPEG-21: ISO/IEC 21000 (all parts)
MPEG-7: ISO/IEC 15938
MP3:  MPEG-1/2 layer III (audio coding)
RFC:  Request for Comments
SVG:  Scalable Vector Graphics
URI:  Uniform Resource Identifier (IETF RFC 3986)
URL:  Uniform Resource Locator (IETF RFC 3986)
URN:  Uniform Resource Name (IETF RFC 3986)
W3C:  World Wide Web Consortium
XML:  Extensible Markup Language (W3C XML)
5 Conventions
5.1 Naming convention
It should be noted that the Digital Item Declaration Model (clause 6) contains the concept names that are used
throughout the MPEG-21 standard. As such, this model should be considered to be the “ultimate arbiter” of
these MPEG-21 concept names.
5.2 Documentation convention
The semantics of each entity in the Digital Item Declaration Model is specified using the constructs provided
by EBNF [4], and is shown in this document using a specific font and background:
entity ::= (part1 | part2)+ part3*
The syntax of each element in the Digital Item Declaration Representation is specified using the constructs
provided by XML Schema [2].
Element names and attribute names in the representation are in SMALL CAPS. Throughout the document, italics
are used when referring to entities defined in the Digital Item Declaration Model (see clause 4), hereafter
known as the Model.
The syntax of each element in the Digital Item Declaration representation is specified using the following
format.
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ISO/IEC 21000-2:2005(E)
Table 1 — Example element specification

Diagram

Children
Used by
Name Type Description
Attributes
ID ID A unique ID value, which can be referenced by another element.


 
 
 
 
Source  
  
 
 
 
 



The Language Definition clause contains syntax diagrams for each element. Here is an example syntax
diagram with annotations:
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ISO/IEC 21000-2:2005(E)
Optional child
Sequence group
Required child
Parent element
Optional
unbounded
child
Required
unbounded
Choice group
child
Required child
with children

Figure 1 — Example element syntax diagram
Non-normative examples are included in separate clauses, and are shown in this document using a separate
font and background:

example element content


5.3 Namespace prefix conventions
This document makes use of vocabularies from several XML namespaces (where the definition of an XML
namespace is as specified in W3C XMLNAMES [7]). Qualified Names are written with a namespace prefix
followed by a colon followed by the local part of the Qualified Name as shown in the following example.
EXAMPLE didl:DIDL
For the purposes of this document the Table below gives the namespace prefixes associated with the
identified namespaces.
Table 2 — Namespace prefixes
Namespace prefix Namespace
didmodel urn:mpeg:mpeg21:2002:02-DIDMODEL-NS
didl urn:mpeg:mpeg21:2002:02-DIDL-NS
dii urn:mpeg:mpeg21:2002:01-DII-NS
mx urn:mpeg:mpeg21:2003:01-REL-MX-NS
sx urn:mpeg:mpeg21:2003:01-REL-SX-NS
dia urn:mpeg:mpeg21:2003:01-DIA-NS
diac urn:mpeg:mpeg21:2003:01-DIA-DIAC-NS
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ISO/IEC 21000-2:2005(E)
mpeg7 urn:mpeg:mpeg7:schema:2001
dsig http://www.w3.org/2000/09/xmldsig#
rdf http://www.w3.org/1999/02/22-rdf-syntax-ns#
xml
http://www.w3.org/XML/1998/namespace
xi http://www.w3.org/2001/XInclude
xsd http://www.w3.org/2001/XMLSchema
xsi http://www.w3.org/2001/XMLSchema-instance
dc http://purl.org/dc/elements/1.1/
uaprof http://www.wapforum.org/profiles/UAPROF/ccppschema-20000405
foo
This namespace prefix is used for demonstration only.

6 Digital Item Declaration Model
6.1 Purpose and Overview
The purpose of this clause is to describe a set of abstract terms and concepts to form a useful model for
defining Digital Items. Within this model, a Digital Item is the digital representation of an Asset, and as such, it
is the unit that is acted upon (managed, described, exchanged, collected, etc.) within the model. The goal of
this model is to be as flexible and general as possible, while providing for the “hooks” that enable higher level
functionality. This, in turn, allows the model to serve as a key foundation in the building of higher level models
in other MPEG-21 elements (such as Identification or IPMP). This model specifically does not define a
language in and of itself. Instead, the model helps to provide a common set of abstract concepts and terms
that can be used to define such a scheme, or to perform mappings between existing schemes capable of
Digital Item Declaration, for comparison purposes.
6.2 Abstract Model
6.2.1 Entity Descriptions
In the following descriptions, the defined entities in italics are intended to be unambiguous terms within this
model. The prose descriptions define the semantic “meaning” of the terms, and the EBNF representations
define the precise intended relationship or structure between terms within the model.
6.2.2 container
A container is a structure that allows items and/or containers to be grouped. These groupings of items and/or
containers can be used to form logical packages (for transport or exchange) or logical shelves (for
organization). Descriptors allow for the “labelling” of containers with information that is appropriate for the
purpose of the grouping (e.g. delivery instructions for a package, or category information for a shelf).
It should be noted that a container itself is not an item; containers are groupings of items and/or containers.
container ::= descriptor* container* item*
6.2.3 item
An item is a grouping of sub-items and/or components that are bound to relevant descriptors. Descriptors
contain information about the item, as a representation of an Asset. Items may contain choices, which allow
them to be customized or configured. Items may be conditional (on predicates asserted by selections defined
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ISO/IEC 21000-2:2005(E)
in the choices). An item that contains no sub-items can be considered a whole -- a logically indivisible Asset.
An item that does contain sub-items can be considered a compilation -- an Asset composed of potentially
independent sub-parts. tems may also contain annotations to their sub-parts.
The relationship between items and Digital Items (as defined in ISO/IEC 21000-1:2001, MPEG-21 Vision,
Technologies and Strategy) could be stated as follows: items are declarative representations of Digital Items.
item ::= condition* descriptor* choice* (item | component)* annotation*
6.2.4 component
A component is the binding of a resource to a set of descriptors. These descriptors are information concerning
all or part of the specific resource instance. Such descriptors will typically contain control or structural
information about the resource (such as bit rate, character set, start points or encryption information) but not
information de
...