Multimedia Standards and Emerging Products
DRAFT - December 5, 1995
The following information is divided into two categories. Category A concerns
applicable standards while category B discusses products supporting the
standard. Category C offers comments.
The MITRE Corporation
1. H.320 Industry Profile for Video Conferencing, VTC001-Rev.
1, April 25, 1995. This is the second issue of this document which was
written under DISA contract by the Corporation for Open Systems (COS) International.
The document is now considered the primary guidance for DoD VTC and replaces
Mil Std 188-331. The document requires a minimum compliance of Quarter
Common Intermediate Format (QCIF) resolution and G.711 audio. Some of the
ITU-T recommendations, such as G.728, are considered options in this document.
The document provides guidance for secure conferencing including built-in
DES encryption (which no vender presently has). The document states the
method of resynchronization of KGs from both video CODECs and Multipoint
Control Units. One side note is that the Corporation for Open Systems International
is or has gone out of existence. It was expected that industry would come
and bring products and money to have their equipment "certified"
against the profile. They did not come. It is unclear if DISA will be responsible
for the next revision of this document.
A. Standards and other documents involving multimedia
2. H.320 Video teleconferencing Services at 56 to 1,960 KB/S.
December 21, 1992. Federal Information Processing Standard (FIPS) 178 published
by the National Institute of Standards and Technology. This was the first
published document for VTC standards and essentially references the five
(then) existing ITU-T (formerly CCITT) video standards and four audio standards. Most
importantly, it states that acquisition of new equipment purchased after
June 1, 1993 shall comply with the standard. The COS profile references
the FIPS 178 standard.
3. H.320 The International Telecommunications Union - Telecommunication
Standardization Sector (ITU-TSS) created the set of international standards
(actually recommendations), sometimes called px64, which fall under the
umbrella standard H.320 entitled Narrowband Visual Telephone Systems and
Terminal Equipment. One of the most recently ratified standards is H.321
which provides guidance for operation over ATM networks. Some of these recommendations
include H.261 Video Compression; H.221 Frame Structure for Audio Visual
Services; G.711, G.722, and G.728 Audio Compression; H.231 Multipoint Control
Services; and H.233 DES Encryption.
4. MPEG Moving Pictures Experts Group (MPEG) was formed as a subcommittee
of the International Standards Organization ISO) and the International Electrotechnical
Commission (IEC) to establish a video compression standard. The principal
activities has been MPEG 1 and MPEG 2, MPEG 1 was originally intended for
use with digital storage media operating at up to T1 (1.5 Mbps). However
the syntax of MPEG 1 allows rates as high as 105 Mbps. MPEG 1 is suited
for movies on demand including use of CD-ROMs because it is optimized for
progressive scanned source material (i.e., film).
MPEG 2 is optimized for higher data rate interlaced video applications,
including HDTV, primarily in the 3 to 15 Mbps range. It can function at
rates up to 100 Mbps. It can also function at lower data rates down to 384
kbps. The flexibility of the algorithms for MPEG 1 and MPEG 2 is expected
to permit future improvements in performance by upgrading only the encoder.
Existing decoders, including set top boxes, would require no upgrades to
accept and decode the improved compressed video stream. MPEG 2 is intended
to be a compatible extension to MPEG 1 meaning that an MPEG 2 decoder will
be able to decode MPEG 1 signals. However, the reverse is not true. MPEG
2 appears to be the major developing standard.
MPEG 4 work began about 2 years ago to develop audiovisual coding schemes
for low bit rate wireless communications. It uses object-based audiovisual
coding and has been expanded to target a broader spectrum of applications
including audiovisual data (TV, film), interactivity (computer), and wireless
(telecommunications). The preliminary testing was scheduled for November
1995 with final testing in November 1996. A working draft of the standard
is scheduled for July 1997 with a final standard in the 1998 time frame.
Based on this schedule, COTS products may not be available before 1999.
5. JPEG The Joint Photographic Experts Group (JPEG) created a compression
algorithm that was originally designed for compressing still frames. The
compression is similar to H.261 under H.320 but pays specific attention
to retaining image detail as opposed to motion compensation. Because plug-in
video compression boards using JPEG (as opposed to MPEG) compression were
available first, (by C-Cube Corporation), this compression has been expanded
to include motion JPEG (M JPEG) which has been used for real time digitization
of motion images for storage on magnetic or optical media. Some companies
providing post production equipment feel that using motion JPEG at low compression
ratios (3 to 5) provide an edited motion video clip that is superior to
one using MPEG (it has less motion artifacts). JPEG, unlike MPEG, does not
define a standard key and therefore equipment of different manufacturers
cannot share compressed files today. At compression ratios above 20 degradation
becomes very visible. The National Image Transmission Format Standard (NITFS)
version 2.0, which is a Government mandated standard, includes the JPEG
6. T.120 The T.120 standard is intended to support common whiteboard
and applications sharing. The T.120 standard was also created by the ITU-TSS
and consists of a set of recommendations covering a series of communication
and application protocols and services supporting real-time, multipoint
data communications. One of its principal applications is collaborative
computing. Some of these recommendations are T.122 Multipoint Communication
Service, T.123 Network Specific Transport Protocols, T.124 Generic Conference
Control, and T.126 Still Image Exchange. While the majority of the T.120
standard has been ratified, some areas within the set of recommendations
are still being finalized.
7. HDTV High Definition Television (HDTV) initially started as a
30 megahertz (MHz) wideband analog system (Japan's Muse System) but has
undergone great change in the U.S. since the FCC stated that it must be
limited to a single 6 MHz channel. The more than 30 proposals were reduced
first to 5 and then to 4 systems to be tested. All 4 systems were backed
by coalition of companies. Rather than pick a specific winner, the FCC suggested
a grand alliance between all parties with a final system proposed by the
alliance (this is a good way of not getting sued). The final proposal includes
the use of the MPEG 2 technique for video compression. In addition, a supplementary
format called Standard Definition TV (SDTV) has been proposed that allow
broadcasters some leeway on the definition of High Definition. The SDTV
digital format provides for four sub HDTV resolution levels. The FCC is
expected to adopt an advanced TV standard later this year that will incorporate
8. DISN Video Services Defense Information Systems Network (DISN)
Video Services-Global, RFP DCA200-95-R-0068, August 31, 1995. The DISN
Video Services RFP is scheduled to replace video conferencing over the Defense
Communications Telecommunications Network (DCTN). The principal standards
are listed in sections 2.2.1 and 2.2.2 of the statement of work. The principal
standard listed is the Corporation for Open Systems COS VTC 001 profile.
Also referenced in the document is the ITU-T H.320, and ITU-T G.728 audio
standard. The H.320 is the ITU umbrella standard for VTC. The G.728 audio
standard is listed because the COS profile lists it as an option and not
a requirement. The G.728 audio compression standard is a requirement under
the DISN Video Services to assure high quality video at 128 kbps VTC service.
The document also lists compliance with other standards, such as T.120,
when they become available.
9. Workstation VTC Workstation VTC and Collaborative
Computing over GCCS LES Test Bed, November 20, 1995 MITRE W032-L-015
Technical Letter by Charles King. This technical letter is a short look
at applicable standards and emerging products that will support VTC and
collaborative computing over Asynchronous Transfer Mode (ATM) transmission
services. The report suggests that this technology is fluid and caution
should be taken in the selection of products to be tested over the Global
Command and Control System - Leading Edge Services.
10. DISA VTC Global Defense Information Systems network (DISN)
Video teleconferencing (VTC) Roadmap, April 1993 Joint Interoperability
and Engineering Organization Center for Engineering Mr. Robert Beall and
Mr. David Rouse. This document presents a DISA approach for achieving a
global VTC service using standards-based VTC over dial-up connections. Standards
and DoD VTC interoperability policy is provided in section 4.2. A goal architecture
using broadband ISDN services is stated in section 5.4.
B. Companies and Products Supporting Standards
1. H.320 Compression labs Inc., PictureTel, VTEL, British Telecom,
Tandberg, Hitachi, Panasonic, and Mitsubishi all provide products that are
H.320 standards compliant. In addition, Vivo has introduced an all software
H.320 capability for the Pentium 120. Presently, no COTS products are identified
as meeting the new emerging H.321, H.322, and H.323 standards for packet-based
communications. However, some products are expected in the 1996 time frame.
2. MPEG Compression Labs Inc. (CLI) is in process of upgrading its
Magnitude video encoders to comply with MPEG II. This work is principally
being done for Thomson for its DirecTV program to improve video encoding
for satellite transmission. The Magnitude system allows dynamic allocation
of required bandwidth from one video channel to another. MEG II is scaleable
and provides for predictive (interpretive) frames when used above 2 Mbps.
DirecTV can encode between T1 and 15 Mbps with set top boxes capable of
decoding the various data rates. MPEG II can also be used at rates below
T1 and down to 384 kbps using the H.262 compression standard which does
not include predictive frames. DirecTV normally operates at compression
data rates above 3 Mbps in order to provide TV images equal to or exceeding
video home system (VHS) quality (about 250 lines resolution). Bill Butterworth
of Thomson states that "the whole world is settling on MPEG 2"
(for high data rate compression).
3. MPEG Scientific Atlanta is building MPEG video encoders and decoders
that will operate at data rates from less than 1 Mbps to 15 Mbps. They are
working with Time Warner in the Full Service Network test project in Orlando
Fla. This network includes movies on demand as well as home shopping services
over an ATM network to 4000 customers.
4. MPEG 1 Hewlett Packard has already introduced MPEG 1 software
decoding in its low-end UNIX workstations. PCs and Macs are expected to
provide software MPEG 1 decompression as a standard capability in 1996.
Visionetics International has a plug-in card that permits MPEG play back
of digital video from CD ROM or hard drive.
5. MPEG 2 Several MPEG encoders are available for desktop use but
are generally expensive and can cost anywhere from $13,900 to $150,000 for
a CD recording system. Optivision has announced the Opt/Video MPEG-2 Encoder
for workstations. Presently the are supplying the product as part of a fully
configured workstation that includes 2 Gigabytes of storage. Other manufacturers
include Alpha Systems Lab, Digital Video Systems, FutureTel, and Sonic Solutions.
6. T.120 DataBeam Corporation produces a product called FarSite.
FarSite 2.0 provides T.120 compatibility including multipoint for the purpose
of document sharing and common whiteboard. This company provides a collaborative
computing product (non T.120 compliant) for use with the Defense Commumications
Telecommunications Network (DCTN) and for the Secure Video Teleconferencing
System. The FarSite product is one of the first COTS tools that support
the new emerging T.120 set of recommendations. The FarSite product has T.123
compliant transport stacks for PSTN, TCP/IP, and IPX. DataBeam also has
a T.120 tool set to support application program development.
7. T.120 ConferTech conferencing bridge. ConferTech has announced
its first (beta) release of a multipoint document conferencing bridge, called
Prelude, meeting T.120 standards. The conferencing bridge may be used in
conjunction with an audio bridge to provide low data rate audio/graphics
conferencing using the Public Switched telephone Network and V.32 bis or
8. T.120 Polycom has announced a new product called ShowStation which
is a document conferencing product that is intended to support T.120 conferencing.
The product consists of an audio conferencing station that is used over
standard phone line, and a document conferencing projector connected to
a V.34 MODEM. The unit may be connected to the ConferTech voice/data conferencing
9. T.120 Apple Computer is integrating the DataBeam T.120 tools into
the Apple QuickTime Conferencing products. This will permit sharing of information
across other computer platforms including PCs.
10. T.120 (future) The Intel Proshare product presently uses Indeo
for video compression and therefore is not H.320 compliant. However they
have a transcode capability that permits the Proshare to be interoperable
with H.320 products over the VideoServer Corporation multipoint control
unit (MCU), Intel states they are actively involved in the T.120 standard
through the International Multimedia teleconferencing Consortium . They
expect to have supporting products once all T.120 recommendations are complete
and ratified by the ITU-T. They are emphasizing interoperability with applications
running on IBM, Compact and other PC platforms. As a result IBM and Compac
are endorsing the Intel Effort
11. T.120 (future) Microsoft Corporation has entered into an agreement
with DataBeam to use their T.120 tool set to enhance the new Microsoft Windows
95 operating system for use with multipoint conferencing capabilities based
on the T.120 standard. The emphasis will be real time collaboration in a
12. JPEG/MPEG Non linear editing systems are using a combination
of motion JPEG, MPEG, and Intel's Digital Video Interactive (DVI). Truevision
presently supports motion JPEG but expects to support the MPEG standard.
The Avid Media suite supports JPEG compression. Fast Electronics supports
motion JPEG but has an optional MPEG extension. The Matrox Corporation Studio
product also uses motion JPEG for non linear (digitized video) editing.
Sigma Designs offers an authoring system that captures video in an MPEG
format edits the images using Adobe's Premiere editing system and then transcodes
the final product into MPEG 1. TouchVision Systems Inc.'s D/Vision Pro uses
the IBM/Intel proprietary Digital Video Interactive (DVI) compression algorithm.
Intelligent Resources Explorer authoring system supports MPEG 1.
13. JPEG The army has used a Macintosh computer to edit images and
JPEG for transmission over INMARSAT telephone terminal to the Pentagon.
The Phototelesis Corporation model ACT-101 video capture unit is used throughout
DoD and is certified to be compliant with the NITF standard.
C. Author Comments
1. H.320 The H.320 standard is now a solid standard with several
companies providing mature COTS products all of which have been tested for
interoperability. This standard is designed to support VTC over switched
network services that have guaranteed bit streams such as ISDN.
2. H.321, H.322, H.323 These are brand new standards that are designed
for packet transmission of VTC. Presently there are no products specifically
meeting these new standards. Products are expected over the next 2 years.
Of specific interest is the H.321 standard for supporting VTC using the
3. T.120 This standard is also new and designed to meet applications
sharing and common whiteboard needs. Present products are limited and are
primarily being used at low data rates of 28.8 kbps. Again, expect a 2-year
lag in product availability. The T.120 standard will be used as a supporting
element of VTC as well as stand alone audio graphics conferencing.
4. MPEG/JPEG MPEG 2 is the fastest growing compression standard with
primary use in set top boxes (for home TV) and some use in video image compression,
store and retrieval (video servers). As stated above, the JPEG standard
is part of the NITFS 2.0. The Central Imagery Office is responsible for
5. HDTV This technology has been very slow to emerge and the present
economy has not created any pent-up demand. Sales in Japan for their HDTV
has been diminishing as purchasing power decreases. There are advocates
for use of HDTV in telemedicine and other uses where high resolution is
desired. The cost of products may be an important factor in growth of HDTV.
At least one article predicts that HDTV will not be widespread and will
be very expensive for the near term (year 2000).