TOKYO, April 10 /PRNewswire/ -- Five Japanese companies today announced
that their jointly proposed format for transferring MPEG-4 streams over the
Internet has now been accepted by three key organizations that promote
development of Internet protocols. Toshiba Corporation, NEC Corporation, Oki
Electric Industry Co., Ltd., Matsushita Electric Industrial Co., Ltd. and
Nippon Telegraph and Telephone Corporation confirmed that the 3G Partnership
Project (3G-PP) has joined the Internet Engineering Task Force (IETF) and the
International Telecommunications Union (ITU) in supporting the standard, a
move expected to bring uniformity to MPEG-4 content on the Internet and
delivered over mobile networks.
The new transfer format is based on the Real-time Transport Protocol (RTP)
standardized by IETF in 1996, rather than TCP/IP, which IP networks typically
use for their transfer protocol. However, if TCP/IP detects any loss of data
during transmission, it automatically retransmits it. The practical result is
delays in data transfers that are unacceptable for real-time transfers of
audio and video signals, particularly in streaming video and audio.
RTP is functionality suited for carrying real-time content as it provides
support for applications with real-time properties, including timing
reconstruction and loss detection. RTP uses UDP/IP, which doesn't have
resending process characteristics. It places RTP headers in each packet that
contains a timestamp, enabling synchronized display of audio and video signals
at receivers, and sequence numbers to support packet loss detection. These
characteristics enable timely data delivery with less degradation. RTP is
widely used for audio and video distribution over the Internet, Internet
tele-conferencing systems and Voice over IP (VoIP).
RTP is designed to define payload formats for each audio-video medium
transferred. This is the area where the solution proposed by the five
Japanese companies has been accepted for MPEG-4 audio and video signals.
A characteristic of the RTP payload format for MPEG-4 video is the
provision of MPEG-4 error resiliency tools, to reduce packet loss. In order
to improve transmission error resiliency, the MPEG-4 coding exploits the video
packet approach within MPEG-4's error resilience tools, which subdivides the
picture frames while coding. MPEG-4 also employs a technique called Header
Extension Code (HEC), a 1-bit field introduced in each video packet. If this
bit is set, the important header information that describes the video frame is
repeated in the video packet. By checking this header information in the
video packets against the information received at the beginning of the video
frame, the decoder can ascertain if the video frame header is received
correctly. If the video frame is corrupted, the decoder can still decode the
rest of the data in the video frame using the header information that is
repeated in the video packets.
The RTP payload format for MPEG-4 audio is an adoption of Low-overhead
Audio Transport Multiplexing (LATM) technology, which effectively transfers
multiple audio frames with a very low overhead.
It also offers an advantage in the comparative simplicity of the RTP
format, in that audio and video streams are directly mapped onto the RTP
packet and do not require specific headers or multiplexing.
The five companies held interoperability tests on the transfer format and
confirmed its stability and reliability. The format was adopted by the IETF
as the RTP payload format for MPEG-4 audio and video signals, by the 3G
Partnership Project (3G-PP) in its packet switched multimedia streaming
service standard for 3G mobile phones, and by the ITU Telecommunications
Standardization Sector (ITU-T) in its recommendation for multimedia
conferencing over packet-based networks such as LANs and the Internet.
The standardization will greatly contribute to promoting audio-video
distribution on the Internet and in bringing the distribution service to
next-generation cellular phones. It is especially important for such
applications as Internet telephony and cellular telephony, where a high level
of interoperability is required.
About Toshiba Corporation:
Toshiba Corporation is a leader in information and communications systems,
electronic components, consumer products and power systems. The company's
integration of these wide-ranging capabilities assures its position as an
innovator in advanced components, products and systems. Its next-generation
MPEG-4 and wireless communications technologies have assured Toshiba's
leadership in W-CDMA development in Japan, where it is the technology
development partner of NTT DoCoMo -- the country's leading mobile service
provider. In fiscal 1999, Toshiba had 191,000 employees worldwide and
recorded sales of 5,749 billion yen (approx. US$54 billion). Visit Toshiba's
web site at http://www.toshiba.co.jp/index.htm .
About NEC Corporation:
NEC Corporation (Nasdaq: NIPNY) (FTSE: 6701q.l) (TSE: 6701) is a leading
provider of Internet solutions, dedicated to meeting the specialized needs of
its customers in the key computer, network and electron device fields through
its three market-focused in-house companies: NEC Solutions, NEC Networks and
NEC Electron Devices. NEC Corporation, with its in-house companies, employs
more than 150,000 people worldwide and saw net sales of 4,991 billion yen
(approx. US$48 billion) in fiscal year 1999-2000. For further information,
please visit the NEC home page at: http://www.nec.com .
About Oki Electric Industry Co., Ltd.:
Founded more than a century ago in 1881, Oki Electric Industry Co., Ltd.
is Japan's first telecommunications manufacturer headquartered in Tokyo,
Japan. With more than 21,000 employees worldwide, Oki Electric provides
customers with top-notch products and technologies for telecommunication
systems, information systems and electronic devices. Visit Oki's global web
site at http://www.oki.com .
About Matsushita Electric:
Matsushita Electric Industrial Co., Ltd. (NYSE: MC), best known for its
Panasonic brand name, is a worldwide leader in the development and manufacture
of electronics products for a wide range of consumer, business, and industrial
needs. Matsushita is playing a major role in the standardization bodies such
as MPEG and 3G-PP, and holding a leading position in the marketing of wireless
communication terminals, MPEG-4 LSI and so on. Based in Osaka, Japan, the
company recorded consolidated sales of US$68.9 billion for the fiscal year
ended March 31, 2000. For further information, please visit our web site at
About Nippon Telegraph and Telephone Corporation:
Nippon Telegraph and Telephone Corporation (NTT) implemented a major
reorganization and was reborn in July 1999 as the new NTT Group. NTT Group
has put forward the slogan "Global Information Distribution Corporate Group"
as being representative of its policy for business activities, which are aimed
at the creation of a rich "information distribution" market where the flow of
information will give birth to new value. The goal of the Group is to work
toward creating new opportunities for "Information distribution" business in a
variety of forms, not limited to the traditional telecommunications field but
also including such efforts as the construction of platforms to safely and
efficiently distribute videos and other types of content. NTT Group has
224,000 employees and annual sales of 10,421 billion yen (approx.
US$97 billion). Please visit NTT home page at
SOURCE Toshiba Corporation