Last update: 2011/08/21
MPEG-A: from technology standards to application formats.
In the typical MPEG anticipative fashion, for several years discussions were held about "what else does industry need from MPEG?". Finally at the Munich meeting (March 2004) MPEG came to the conclusion that while MPEG had produced many component standards, the integration of technologies, save for the canonical Aido-Video-System integration, had been left to implementers. The result has been that, e.g. ATSC uses MPEG-2 Systems and Video but a different Audio than specified by MPEG, and DivX uses MPEG-4 Visual, MP3 and AVI. This meant that while (some) components were standard and provided interoperability, the complete service package or application was not interoperable.
Implementers want to retain the freedom to make individual decisions in terms of what components technologies they should use for their products and services, but this is paid by end users who are confronted with incompatibilities between different system implementations.
So MPEG decided to enter the “system integration” area. This was done because MPEG has knowledge about (most of) the technologies needed, internal expertise to do the integration job and the appropriate industry representation.
Multimedia Application Formats (MAF) is the name of the new standard suite that bears the nice looking ISO number 23000, obtained through the well-known channels. MAFs specify how to combine metadata with media information typically, but not exclusively, packaged in an MPEG-4 file format to enable media interchange, management, editing, and presentation.
Part 1 "Purpose for Multimedia Application Formats" is, like MPEG-21 Part 1, an informative document outlining the scope of the ISO/IEC 23000 suite.
Part 2 "Music Player Application Format" (MPAF) specifies a format to carry MP3 coded audio content in MPEG-4 File Format augmented by and a JPEG image for cover art and simple MPEG-7 metadata commonly expressed in ID3 tags, such as Song title, Album title, Artist, Year, Comment, Track, and Genre.
Assume that you have an MP3 file with ID3 metadata. An MPAF encoder extracts the ID3 tags and converts the MP3 bitstream in a format that allows the definition of Access Units and ccreates an MP4 file that can also contain JPEG images. The MPAF standard also enables album functionality by making reference to MPEG-21. It allows to collect several song files in the above described song file format into one album file. The second edition of the MPAF has added protection feature by incorporating AES-128 counter mode encryption as default protection tool and MPEG-4 IPMP-X. MPEG-21 IPMP and REL for protection and governance description.
Part 3 "Photo-Player Application Format" (PPAF) specifies a format to carry JPEG images and their associated MPEG-7 metadata in an MPEG-4 file to enable creation, sharing and viewing digital photo albums.
The supported metadata include image-acquisition parameters (e.g. date, time and camera settings) expressed as EXIF metadata and MPEG-7 visual content descriptions expressed as binary MPEG-7 metadata. The latter allow new, content-enhanced functionality, such as intelligent browsing, content-based search or automatic categorisation.
Part 4 "Musical Slideshow Application Format" (MSSAF) is a superset of MPAF and PPAF in the sense that its combines the features of both AFs. in addition to the technologies already employed by the two AFs, MSSAF employs MPEG-4 Part-17 “Streaming Text Format” for timed text and MPEG-4 Part-20 “LASeR” Mini Profile.
Part 5 "Media Streaming Application Format" specifies how to use some MPEG technologies to build a full-fledged media player for streaming governed and ungoverned content. This standard defines by reference to appropriate standards the data formats exchanged between a number of devices used in a media streaming scenario: a Content Provider Device, a Licence Provider Device, an IPMP Tool Provider Device, a Domain Management Device and a Media Streaming Player.
In the most general case a Media Streaming Player obtains streaming content from a Content Provider Device using a Content Access Protocol. In order to use that content, a Media Streaming Player obtains a licence from a Licence Provider Device using a Licence Access Protocol. Further, to actually process the content, a Media Streaming Player may need to obtain the appropriate IPMP Tools from an IPMP Tool Provider Device using an IPMP Tool Access Protocol, as shown in Fig. 1.
Fig. 1 - Reference diagram of MSAF standard
Part 6 "Professional Archival Application Format" (PAAF) provides a standardised packaging format for digital files. The format is an implementation of the information package specified by the Reference Model of Open Archival Information System (OAIS), a framework for long-term digital information preservation.
PAAF specifies metadata formats to describe
and it specifies
Part 7 "Open Access Application Format" (OAAF) is a packaging format designed for the release and exchange of content roghts to which is owned by users who have an interest in releasing so that other users can freely access it without making the content "public domain". This was part of a proposal of a DMP use case.
OAAF packages different content types into a single container file and provides a mechanism to attach metadata information, by using a series of technologies, in particular
Part 8 "Portable Video Application Format" (PVAF) defines a format for the use of video files on portable devices to give users the possibility to use a local resource interactively.
Part 9 "Digital Multimedia Broadcasting Application Format" (DMBAF) specifies how to combine the variety of DMB resources and associated information in a well-defined file format to facilitate interchange, management, editing, and presentation of DMB content. Digital Multimedia Broadcasting (DMB) is a mobile TV service enabling users to acquire and consume information anywhere.
Part 10 "Surveillance Application Format" (SAF) specifies the combination of audio and video content drawn from from MPEG technologies, related metadata and file format, suitable for surveillance.
Part 11 "Video Stereoscopic Application Format" (VSAF) defines a format for a creator to take and for a service provider to distribute stereoscopic images, enabling users to have more realistic experiences (with or without special glasses) and to store the stereoscopic content for possible redistribution.
Part 12 "Interactive Music Application Format" (IMAF) defines a format to package interactive music content with audio tracks before mixing, in order to allow users to freely control individual audio tracks. The producer can create several versions (producer mixing 1, producer mixing 2, karaoke, rhythmic, and so on) with just one piece of music, using the metadata structure for mixing information.
Mopre parts are being developed but they will be introduced later .
