MPEG-21
Encyclopedia
The MPEG-21 standard, from the Moving Picture Experts Group
, aims at defining an open framework for multimedia
applications. MPEG-21 is ratified in the standards ISO/IEC 21000 - Multimedia framework (MPEG-21).
MPEG-21 is based on two essential concepts:
Digital Items can be considered the kernel of the Multimedia Framework and the users can be considered as who interacts with them inside the Multimedia Framework. At its most basic level, MPEG-21 provides a framework in which one user interacts with another one, and the object of that interaction is a Digital Item. Due to that, we could say that the main objective of the MPEG-21 is to define the technology needed to support users to exchange, access, consume, trade or manipulate Digital Items in an efficient and transparent way.
MPEG-21 Part 9: File Format defined the storage of an MPEG-21 Digital Item in a file format based on the ISO base media file format
, with some or all of Digital Item's ancillary data (such as movies, images or other non-XML data) within the same file. It uses filename extensions .m21 or .mp21 and MIME
type application/mp21.
" standard as means of managing restrictions for digital content usage. As an XML
-based standard, MPEG-21 is designed to communicate machine-readable license information and do so in a "ubiquitous, unambiguous and secure" manner.
Among the aspirations for this standard that the industry hopes will put an end to file sharing
is that it will constitute: "A normative open framework for multimedia delivery and consumption for use by all the players in the delivery and consumption chain. This open framework will provide content creators, producers, distributors and service providers with equal opportunities in the MPEG-21 enabled open market."
Moving Picture Experts Group
The Moving Picture Experts Group is a working group of experts that was formed by ISO and IEC to set standards for audio and video compression and transmission. It was established in 1988 by the initiative of Hiroshi Yasuda and Leonardo Chiariglione, who has been from the beginning the Chairman...
, aims at defining an open framework for multimedia
Multimedia
Multimedia is media and content that uses a combination of different content forms. The term can be used as a noun or as an adjective describing a medium as having multiple content forms. The term is used in contrast to media which use only rudimentary computer display such as text-only, or...
applications. MPEG-21 is ratified in the standards ISO/IEC 21000 - Multimedia framework (MPEG-21).
MPEG-21 is based on two essential concepts:
- definition of a Digital ItemDigital ItemDigital Item is the basic unit of transaction in the MPEG-21 framework. It is a structured digital object, including a standard representation, identification and metadata....
(a fundamental unit of distribution and transaction) - users interacting with Digital Items
Digital Items can be considered the kernel of the Multimedia Framework and the users can be considered as who interacts with them inside the Multimedia Framework. At its most basic level, MPEG-21 provides a framework in which one user interacts with another one, and the object of that interaction is a Digital Item. Due to that, we could say that the main objective of the MPEG-21 is to define the technology needed to support users to exchange, access, consume, trade or manipulate Digital Items in an efficient and transparent way.
MPEG-21 Part 9: File Format defined the storage of an MPEG-21 Digital Item in a file format based on the ISO base media file format
ISO base media file format
ISO base media file format defines a general structure for time-based multimedia files such as video and audio. It is used as the basis for other media file formats...
, with some or all of Digital Item's ancillary data (such as movies, images or other non-XML data) within the same file. It uses filename extensions .m21 or .mp21 and MIME
MIME
Multipurpose Internet Mail Extensions is an Internet standard that extends the format of email to support:* Text in character sets other than ASCII* Non-text attachments* Message bodies with multiple parts...
type application/mp21.
Digital Rights Management
MPEG-21 defines also a "Rights Expression LanguageRights Expression Language
A Rights Expression Language or REL is a machine-processable language used for Digital Rights Management.Most REL are expressible in XML, but this is not a requirement and any format could be used.XrML began in Lisp. Some use RDF and RDF Schema...
" standard as means of managing restrictions for digital content usage. As an XML
XML
Extensible Markup Language is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards....
-based standard, MPEG-21 is designed to communicate machine-readable license information and do so in a "ubiquitous, unambiguous and secure" manner.
Among the aspirations for this standard that the industry hopes will put an end to file sharing
File sharing
File sharing is the practice of distributing or providing access to digitally stored information, such as computer programs, multimedia , documents, or electronic books. It may be implemented through a variety of ways...
is that it will constitute: "A normative open framework for multimedia delivery and consumption for use by all the players in the delivery and consumption chain. This open framework will provide content creators, producers, distributors and service providers with equal opportunities in the MPEG-21 enabled open market."
See also
- Digital Rights ManagementDigital rights managementDigital rights management is a class of access control technologies that are used by hardware manufacturers, publishers, copyright holders and individuals with the intent to limit the use of digital content and devices after sale. DRM is any technology that inhibits uses of digital content that...
- AxmedisAxmedisAXMEDIS was initially created as a research project partially supported by the European Commission under the Information Society Technologies programme of the Sixth Framework Programme . It stands for "Automating Production of Cross Media Content for Multi-channel Distribution". Now it is under...
AXMEDIS are free MPEG-21 tools for authoring and play
Further reading
- Part 1: Vision, Technologies and Strategy
- Part 2: Digital Item Declaration
- Part 3: Digital Item Identification
- Part 4: Intellectual Property Management and Protection Components
- Part 5: Rights Expression Language
- Part 6: Rights Data Dictionary
- Part 7: Digital Item Adaptation and Session Mobility
- Part 8: Reference Software
- Part 9: File Format (.m21 or .mp21)
- Part 10: Digital Item Processing and C++ bindings
- Part 11: Evaluation Tools for Persistent Association
- Part 15: Event Reporting
- Part 17: Fragment Identification for MPEG Resources
- Part 18: Digital Item Streaming