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InfoSatellite.com / News MPEG-4 under the spotlights
The standard that came as an option to Microsoft´s monopoly gains the attention and makes its way to total acceptance.
About MPEG-4 The standard provides a great deal of tools for the coding of audio-visual objects. The visual part provides five profiles for the coding of natural, synthetic, and synthetic/natural hybrid visual content. MPEG-4 points out the needs for an increasing audio-visual content in digital form. Unlike the linear coding of audio and video in the previous MPEG-1/2, the MPEG-4 coding is based on objects, which can be an image or a video: a car in movement or a still picture. It can also be an audio object like the sound of a dog barking. This association between audio and video is called audio-visual object. Another functions addressed in the system are:
Functionalities of MPEG-4 Its technology brings to users much more flexibility of production content. It is also possible to manage and protect content owners´ rights. The standard offers transparent information, which can be interpreted and translated into the appropriate native signaling messages of each network with the help of relevant standards bodies (feature that benefits network service providers). Higher levels of interaction with the content can also be achieved. MPEG-4 Version 1 Among the audio functions in the format is the facilitation
of a variety of applications including multichannel audio,
intelligible speech and natural or synthesized sounds.
It also supports the use of audio objects consisting of
speech signals (coding using bitrates up to 24kbit/s)
as well as synthesized speech, where the bitrates range
from 200 bit/s to 1.2Kbit/s. The first version of the
MPEG-4 supports bitrates bewteen 5kbit/s and 10Mbits/s,
progressive formats, interlaced videos and resolutions
to beyond HDTV. The format is said to have efficient compression
of videos and textures. One of its functions is called
‘Face Animation’, which allows parameters that
animate synthetic faces to be sent, with one note: the
part standardized by MPEG-4 is restricted to the parameters. MPEG-4 Version 2 The 2nd version of the format is built on the first, being backward compatible with it. With new tools, functions and profiles. The audio part is also extended from the first version. MPEG-1/2 x MPEG-4 A difference between the former and the new MPEG is that the first standardized a particular type of algorithm while the MPEG-4 is standardizing a group. The hardware that supports MPEG-4 must be flexible in order to execute different groups of algorithms. This brings up an important advantage: The MPEG-4 can be adapted to future coding technologies. A whole new group of applications will use MPEG-4, such as videoconferences, mobile communications and access to remote video server for multimedia applications. The work is also being focused on digital television, graphical applications and the World Wide Web. MPEG-4 will deliver technology basically for multimedia communication. MPEG-7: Extending the standard According to the MPEG-7 group the standard "aims at offering a comprehensive set of audio-visual descriptions, which will form the basis for applications enabling the needed quality access to content, which implies good storage solutions, high-performance content identification, proprietary assignation, and fast, ergonomic, accurate and personalized filtering, search and retrieval."
In February, 2000, Toshiba announced its first single-chip MPEG-4 videophone System Level IC for IMT-2000. In April of the same year, Philips Digital Network division was showing, with Wave Systems Corp, the company´s MPEG-4 tools and services and wave’s streaming media e-commerce services to content providers and streaming media network companies. The list of companies involved with MPEG-4 include other giants like Compaq, Sony Eletronics, Intel, IBM and Creative Labs. As righteously said by sources, one big catch in MPEG-4 is that it is an alternative to Microsoft´s monopoly. That is reason enough to be adopted at least by companies that wish to reinforce their rights to price and content options.
(Sources: MPEG-4 Industry Forum, Fraunhofer Institute, ZDnet) Related links: |
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