Accessing audio and video used to be a simple matter - simple
because of the simplicity of the access mechanisms and because of the poverty
of the sources. An incommensurable amount of audiovisual information is
becoming available in digital form, in digital archives, on the World Wide Web,
in broadcast data streams and in personal and professional databases, and this
amount is only growing. The value of information often depends on how easy it
can be found, retrieved, accessed, filtered and managed.
The transition between the second and
third millennium abounds with new ways to produce, offer, filter, search, and
manage digitized multimedia information. Broadband is being offered with
increasing audio and video quality and speed of access. The trend is clear: in
the next few years, users will be confronted with such a large number of
contents provided by multiple sources that efficient and accurate access to
this almost infinite amount of content seems unimaginable today. In spite of
the fact that users have increasing access to these resources, identifying and
managing them efficiently is becoming more difficult, because of the sheer
volume. This applies to professional as well as end users. The question of
identifying and managing content is not just restricted to database retrieval
applications such as digital libraries, but extends to areas like broadcast
channel selection, multimedia editing, and multimedia directory services.
This challenging situation demands a
timely solution to the problem. MPEG-7 is the answer to this need.
MPEG-7 is an ISO/IEC standard
developed by MPEG (Moving Picture Experts Group), the committee that also
developed the successful standards known as MPEG-1 (1992) and MPEG-2 (1994), and
the MPEG-4 standard (Version 1 in 1998, and version 2 in 1999). The MPEG-1 and
MPEG-2 standards have enabled the production of widely adopted commercial
products, such as Video CD, MP3, digital audio broadcasting (DAB), DVD, digital
television (DVB and ATSC), and many video-on-demand trials and commercial
services. MPEG-4 is the first real multimedia representation standard, allowing
interactivity and a combination of natural and synthetic material coded in the
form of objects (it models audiovisual data as a composition of these objects).
MPEG-4 provides the standardized technological elements enabling the
integration of the production, distribution and content access paradigms of the
fields of interactive multimedia, mobile multimedia, interactive graphics and
enhanced digital television.
The MPEG-7 standard, formally named
"Multimedia Content Description Interface", provides a rich set of
standardized tools to describe multimedia content. Both human users and
automatic systems that process audiovisual information are within the scope of
MPEG-7.
MPEG-7 offers a comprehensive set of
audiovisual Description Tools (the metadata elements and their structure and
relationships, that are defined by the standard in the form of Descriptors and
Description Schemes) to create descriptions (i.e., a set of instantiated
Description Schemes and their corresponding Descriptors at the users will),
which will form the basis for applications enabling the needed effective and
efficient access (search, filtering and browsing) to multimedia content. This
is a challenging task given the broad spectrum of requirements and targeted
multimedia applications, and the broad number of audiovisual features of
importance in such context.
MPEG-7 has been developed by experts
representing broadcasters, electronics manufacturers, content creators and
managers, publishers, intellectual property rights managers, telecommunication
service providers and academia.
