Multimedia Standards and Emerging Products

DRAFT - December 5, 1995
The MITRE Corporation
Informal Paper
Charles King

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.

A. Standards and other documents involving multimedia standards

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.

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 standard.

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 SDTV.

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 V.34 MODEMs.

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 bridge.

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 Windows environment.

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 compress into

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 ATM protocol.

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 this standard.

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).