is a multimedia content
. This description will be associated with the content itself, to allow fast and efficient searching for material that is of interest to the user. MPEG-7 is formally called Multimedia Content Description Interface
. Thus, it is not
a standard which deals with the actual encoding of moving pictures and audio, like MPEG-1
. It uses XML
to store metadata
, and can be attached to timecode
in order to tag particular events, or synchronise lyrics
to a song
, for example.
It was designed to standardize:
- a set of Description Schemes (short DS in the standard) and Descriptors (short D in the standard)
- a language to specify these schemes, called the Description Definition Language (short DDL in the standard)
- a scheme for coding the description
The combination of MPEG-4 and MPEG-7 has been referred to as MPEG-47.
MPEG-7 is intended to provide complementary functionality to the previous MPEG standards, representing information about the content, not the content itself ("the bits about the bits"). This functionality is the standardization of multimedia content descriptions. MPEG-7 can be used independently of the other MPEG standards - the description might even be attached to an analog movie. The representation that is defined within MPEG-4, i.e. the representation of audio-visual data in terms of objects, is however very well suited to what will be built on the MPEG-7 standard. This representation is basic to the process of categorization. In addition, MPEG-7 descriptions could be used to improve the functionality of previous MPEG standards.
- Provide a fast and efficient searching, filtering and content identification method.
- Describe main issues about the content (low-level characteristics, structure, models, collections, etc.).
- Index a big range of applications.
- Audiovisual information that MPEG-7 deals is : Audio, voice, video, images, graphs and 3D models
- Inform about how objects are combined in a scene.
- Independence between description and the information itself.
Relation between description and content
An MPEG-7 architecture requirement is that description must be separate from the audiovisual content.
On the other hand there must be a relation between the content and description. Thus the description is multiplexed with the content itself.
On the right side you can see this relation between description and content.
MPEG-7 uses the following tools:
- Descriptor (D): It is a representation of a feature defined syntactically and semantically. It could be that a unique object was described by several descriptors.
- Description Schemes (DS): Specify the structure and semantics of the relations between its components, these components can be descriptors (D) or description schemes (DS).
- Description Definition Language (DDL): It is based on XML language used to define the structural relations between descriptors. It allows the creation and modification of description schemes and also the creation of new descriptors (D).
- System tools: These tools deal with binarization, synchronization, transport and storage of descriptors. It also deals with Intellectual Property protection.
On the right side you can see the relation between MPEG-7 tools.
There are many applications and application domains which will benefit from the MPEG-7 standard. A few application examples are:
- Digital library: Image/video catalogue, musical dictionary.
- Multimedia directory services: e.g. yellow pages.
- Broadcast media selection: Radio channel, TV channel.
- Multimedia editing: Personalized electronic news service, media authoring.
- Security services: Traffic control, production chains...
- E-business: Searching process of products.
- Cultural services: Art-galleries, museums...
- Educational applications.
- Biomedical applications.
Software and demonstrators for MPEG-7
- Caliph & Emir: Creation and Retrieval of images based on MPEG-7 (GPL).
- img(Rummager): Download img(Rummager) image retrieval engine and the latest version of MPEG-7 Descriptors as dll for C# (Freeware Applicaton).
- Frameline 47 Video Notation: Frameline 47 from Versatile Delivery Systems. The first commercial MPEG-7 application, Frameline 47 uses an advanced content schema based on MPEG-7 so as to be able to notate entire video files, or segments and groups of segments from within that video file according to the MPEG-7 convention (commercial tool)
- Eptascape ADS100 uses a real-time MPEG 7 encoder on an analog camera video signal to identify interesting events, especially in surveillance applications, check the demos to see MPEG-7 in action (commercial tool)
- IBM VideoAnnEx Annotation Tool: Creating MPEG-7 documents for video streams describing structure and giving keywords from a controlled vocabulary (binary release, restrictive license)
- iFinder Medienanalyse- und Retrievalsystem: Metadata extraction and search engine based on MPEG-7 (commercial tool)
- MPEG-7 Audio Encoder: Creating MPEG-7 documents for audio documents describing low level audio characteristics (binary & source release, Java, GPL)
- XM Feature Extraction Web Service: The functionalities of the eXperimentation Model(XM) are made available via web service interface to enable automatic MPEG-7 low-level visual description characterization of images.
- TU Berlin MPEG-7 Audio Analyzer (Web-Demo): Creating MPEG-7 documents (XML) for audio documents (WAV, MP3). All 17 MPEG-7 low level audio descriptors are implemented (commercial)
- TU Berlin MPEG-7 Spoken Content Demonstrator (Web-Demo): Creating MPEG-7 documents (XML) with SpokenContent description from an input speech signal (WAV, MP3) (commercial)
- MP7JRS C++ Library Complete MPEG-7 implementation of part 3, 4 and 5 (visual, audio and MDS) by IIS, Joanneum Research Institute of Informationssystems and Informationmanagement.
- B.S. Manjunath (Editor), Philippe Salembier (Editor), and Thomas Sikora (Editor): Introduction to MPEG-7: Multimedia Content Description Interface. Wiley & Sons, April 2002 - ISBN 0-471-48678-7
- Harald Kosch: Distributed Multimedia Database Technologies. CRC Press, January 2004 - ISBN 0-8493-1854-8
- Giorgos Stamou (Editor) and Stefanos Kollias (Editor): Multimedia Content and the Semantic Web: Standards, Methods and Tools. Wiley & Sons, May 2005 - ISBN 0-470-85753-6
- Hyoung-Gook Kim, Nicolas Moreau, and Thomas Sikora: MPEG-7 Audio and Beyond: Audio Content Indexing and Retrieval. Wiley & Sons, October 2005 - ISBN 0-470-09334-X