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The following reports of recent standards meetings represent the view of the reporterand are not official, authorized minutes of the meetings.
Report of ITU-T SG16, Multimedia, May 17 - 28, 1999, Santiago, Chile .................................................... 2Documents Approved by Resolution No. 1 Process................................................................................ 2Other Documents Approved by the Study Group ................................................................................... 3Documents Determined (i.e., First Part of the Resolution No. 1 Approval Process) .......................... 4WP1, Low Rate Systems ........................................................................................................................... 5WP2, Services and High Rate Systems................................................................................................... 7WP3, Signal Processing............................................................................................................................. 8Q1/16 WP2, Audiovisual/multimedia Services....................................................................................... 10Q2/16 WP2, Interactive Multimedia Information Retrieval Services (MIRS) ..................................... 11Q3/16 WP2, Data Protocols for Multimedia Conferencing.................................................................... 11Q4/16 WP1, Modems for Switched Telephone Network and Telephone Type Leased Lines............. 12Q5/16 WP1, ISDN Terminal Adapters, and Interworking of DTEs on ISDNs with DTEs on OtherNetworks..................................................................................................................................................... 14Q6/16 WP1, DTE-DCE Interchange Circuits ......................................................................................... 14Q7/16 WP1, DTE-DCE Interface Protocols ............................................................................................. 15Q8/16 WP1, DCE-DCE Protocols ............................................................................................................. 16Q9/16 WP1, Accessibility to Multimedia for People with Disabilities.................................................. 16Q10/16 WP1, Modem Testing................................................................................................................... 18Q11/16 WP2, Circuit Switched Network (CSN) Multimedia Systems and Terminals...................... 18Q12/16 WP2, B-ISDN Multimedia Systems and Terminals ................................................................. 21Q13/16 WP2, Packet Switched Multimedia Systems and Terminals................................................... 23Q14/16 WP2, Common Protocols, MCUs & Protocols for Interworking with H.300-series Terms. ... 31Q15/16 WP3, Advanced Video Coding..................................................................................................... 36Q16/16 and Q17/16, Multimedia Harmonization and Coordination..................................................... 40Q19/16 WP3, Extension to Existing ITU-T Speech Coding Standards at Bit Rates Below 16 kbit/s 41Q20/16 WP3, Audio and Wideband Coding in Public Telecommunication Networks........................ 43Q21/16 WP3, Encoding of Speech Signals at Bit Rates around 4-kbit/s .............................................. 47Q22/16 WP3, Software and Hardware Tools for Standardization of Speech and Audio CodingAlgorithms .................................................................................................................................................. 50Q23/16 WP1, PCM Modems...................................................................................................................... 52ITU-T SG/16 Meeting Roster, May 17 - 28, Santiago Chile ................................................................... 54
Acronym Definitions ......................................................................................................................................... 581999 and 2000 Standards Committee Meeting Schedules as of June 25, 1999 ........................................... 62
* The USA Administration applied the 4-week rule (i.e., requested a further 4 weeks for consideration) on thisRecommendation. However, it is expected to pass. (See Q14/16 report, below.)
Q Title Documents19 Implementors Guide for G.723.1 Annexes A, B and G.729 Annex E TD-26(PLEN)11 H.223 Implementors Guide Update TD-16(PLEN)11 H.324 Implementors Guide Update TD-15(PLEN)13 Implementors Guide for ITU-T H.323, H.225.0, H.245, H.246, H.235 and H.450 TD-37(PLEN),
DCEs operating in the text telephony modeTD-8(PLEN)
* A copyright statement regarding the video material supplied with this Supplement is available in TD-75(PLEN).
In concurrence with ISO/IEC JTC1/SC29 (MPEG), ITU-T SG16 agrees to publish an integratededition of common text Recommendations including the following texts:
1) ITU-T Rec. H.222.0 | ISO/IEC 13818-1, Information technology - generic coding of movingpictures and associated audio information: systems
Study Group 16 held its fourth meeting at the University of Chile in Santiago, at the invitation ofthe Chilean Administration and the University.
SG16 has three Working Parties (WPs):
WP Title Chairman ReportWP1/16 Low Rate Systems John Magill, Lucent (UK) TD-42 (PLEN)WP2/16 Services and High Rate Systems Federico Tosco, CSELT (Italy) TD-59 (PLEN)WP3/16 Signal Processing Simao Campos Neto, Comsat (US) TD-48 (PLEN)
The activities of these Working Parties are reported below.
WORKSHOP ON MULTIMEDIA
A successful workshop on Multimedia Application and Network was held on May 17, 1999, thefirst day of SG16. The program is in Annex 3 to TD-70(PLEN). The presentations from theworkshop are available at:• http://www.ict.uchile.cl/itut.sg16/workshop.html• http://www.itu.int/ITU-T/com16/santiago/index.html
LIAISONS
TD-21(GEN) reports that Q4/4 has Determined (Approval 2/2000) the new X.700 seriestechnical corrigenda which provide guidance in the use of the new ASN.1 Recommendations.New ITU-T recommendations are no longr able to reference ASN.1 1990. The new reference is toX.680-1997 | ISO/IEC 8824-1:1998.
TD-4(GEN) from SG11 provides the IMT-2000 preliminary consolidated work plan.
Activities of SG2: TD-22(GEN) reports on the study of the expansion of E.164 (PSTNnumbering) from 3 to 4 digit country codes. Q1/2 anticipates exhaustion of 3 digit country codesin 10-15 years. TD-24(GEN) provides a very preliminary draft of E.MM, Routing of multimediaconnections when interworking with PSTN, ATM and IP networks. TD-25(GEN) notes theestablishment of a fraud prevention coordinator in SG2 and provides a list of six otherorganizations dealing with fraud prevention. WD2-20 is the Q13/Q14 response to this liaison.The response discusses the capabilities of H.235.
Activities of SG10 on Formal Description Languages:• Q2/10 has developed the ITU-T Object Definition Language Z.130 (TD-7(GEN).• SG10 is updating Recommendation Z.110-1996, Criteria for use of formal description
languages by the ITU-T (TD-8(GEN)). WD2-05 is Q13/16’s response to the Questionnaire forASN.1 and SDL.
• TD-11(GEN) reports that new versions of Recommendations Z.100 (State DescriptionLanguage) and Z.120 (Message Sequence Chart [MSC]) were Determined in February, 1999;Approval is planned for November, 1999. Tool vendors are expected to support the newversions shortly after final approval.
TD-27(GEN) reports that SG12 is developing three recommendations relating to end-to-endperformance:• G.108, Application of the E-Model (G.107) - a planning guide• G.109, definition of categories of speech transmission quality• G.177, transmission planning for voiceband services over hybrid internet/PSTN connections
The activities of SG13 on the GII Project plan, IP Project coordination (SG13 is the Lead SG),IETF coordination (listing of all IETF WGs related to ITU SGs) and multimedia coordination(status of activities in SGs 2, 12, 16) are reported in TD-13(GEN), TD-14(GEN), TD-15(GEN),and TD-16(GEN), respectively. TD-17(GEN) is the Report on SG13 Plenary Meeting and onGII Issues, February 15-26, 1999. (See the Q16/17 report, below.)
TSAG Matters are reported in TD-18(GEN), ITU internal liaison procedures; TD-19(GEN),guidelines for ISOC/IETF collaboration (includes referencing guidelines); and TD-20(GEN), EDHinformation.
FUTURE MEETINGS
A half day meeting of Study Group 16 is planned for September 30, 1999, for the purposes ofapproving appropriate texts, particularly Determined Recommendation G.722.1. Thisopportunity will also be used to approve outputs from the interim meeting of Q16/16 and Q17/16e.g., for input to the October meeting of ITU-T TSAG.
The next full meeting of SG16 is scheduled for February 7-18, 2000.
WP1, LOW RATE SYSTEMS
The Rapporteur for WP1 is J. Magill (Lucent, UK). The agenda for the meeting, together withmeeting schedule and document allocation table is in TD-24(WP1/16). The Working Party 1report of this meeting is comprised of TD-41(PLEN) through TD-47(PLEN). The updatedstatus report for Recommendations that are the responsibility of WP1 is published in TD-46(PLEN).
The questions currently allocated to WP1 (and respective Rapporteurs) are:
Q4 Modems for Switched Telephone Network and Telephone Type Leased Lines (B. Adams,Motorola, USA)
Q5 ISDN terminal adapters, and interworking of DTEs on ISDNs with DTEs on other networks(J. Moughton, UK)
Q9 Accessibility to Multimedia for People with Disabilities (G. Hellström, Ericsson, Sweden)Q10 Modem Testing (G. List, Austria)Q23 PCM Modems (L. Brown, Motorola, USA)
The Q5 session was chaired by the WP1 Chair as J. Moughton has changed companies and is nolonger able to continue as Rapporteur. Because the Rapporteur for Q8 was not available toattend the meeting, the Q8 session was also chaired by the WP1 Chair.
FUTURE OF Q18/16
No further contributions have been received for Q18/16 Interaction of high-speed voiceband dataprocessing systems with signal processing, so in accordance with the proposal at the Sept. 1999meeting of SG16, WP1 agreed to request deletion of Q18 and transfer of the work to SG15. SG15indicated in a Liaison in TD-6(WP1/16) that they are revising the current Q8/15 to includegeneral aspects of interactions among signal processing elements.
REVISIONS TO QUESTIONS IN WP1/16
In preparation for the next study period, WP1 reviewed the text of the current Questions andcurrent activity, and agreed to the changes shown below. Initial draft text for these newQuestions is contained in TD-47(PLEN).
PROPOSED QUESTIONS FOR THE NEXT STUDY PERIOD
Q1A/16 WP1, Voice-band Modems: Specification and Performance Evaluation, proposed as acontinuation of existing Q4/16, Q10/16 and Q23/16. This work is planned to lead to newrecommendations for:• Enhancements to Recommendation V.90 (1998).• Enhancements to Recommendations V.8 and V.8bis.• A network model and test procedures for the evaluation of V.9x series modem performance.
Q1B/16 WP1, DCE-DCE Protocols for the PSTN and ISDN, is proposed as a continuation ofexisting Q5/16 and Q8/16. This study includes the work on HDLC-based protocols for bothmodem-based communication, i.e., V.42 and V.75, and ISDN-based communication, i.e., V.120.Also, data compression on top of these protocols will be addressed. Continued study is necessaryon issues arising from new applications (e.g., IP networks).
Q1C/16 WP1, DTE-DCE Interfaces and Protocols, is proposed as a continuation of existing Q6/16and Q7/16. The need for the continued study of DTE-DCE interfaces and protocols to keep pacewith changing modem and DTE technologies remains of high importance.
Q1D/16 WP1, Accessibility to Multimedia for People with Disabilities, is proposed as acontinuation of existing Q9/16. This work produces and maintains Recommendations formultimedia systems and services of specific interest to people with disabilities. The focus of thenew Question is on the establishment of recommendations for Total Conversation services. TotalConversation is a concept for standardized communication in video, text and voicesimultaneously. While applications include conversation with sign language, lip-reading, text andother alternative communication means, emphasis in the new question is to be placed on designsuitable for all.
Recommendation V.18 is the platform for plain text telephony in the PSTN. RecommendationT.140 is the common text conversation presentation protocol used in all Total Conversationenvironments. Total Conversation is the extension of text conversation from videotelephony to allnetworks. The new question will also address the selection of any perceivable mediapresentation, and to activate media conversions to get intelligible presentation of media.
HOME PHONELINE NETWORKING
The meeting was made aware that some companies intend to request initiation of work in theITU-T on local networking devices that use existing telephone wiring in the home to connect PCsin the home. While WP1 believes that SG16 could undertake this work, it is understood that a
proposal will be made to do the work in SG15. No further action was taken. (See Q4/15 reportin CSR Vol. 10.5.)
WP2, SERVICES AND HIGH RATE SYSTEMS
The WP2 reports of this meeting are contained in TD-58(PLEN) through TD-64(PLEN).
The Rapporteur for Q14/16, G Thom (Delta Information Systems), informed WP2 that, due to theassumption of a new responsibility in his company, he would not be able to remain as Rapporteurfor Q14/16. WP2 thanked G. Thom for the work he has done. SG16 appointed G. Freundlich(Lucent Technologies) as new Rapporteur for Q14/16.
The questions currently allocated to WP2 (and respective Rapporteurs) are:
Austria)Q3 Data Protocols for Multimedia Conferencing (B. DeGrasse, DataBeam, USA)Q11 Circuit Switched Network (CSN) Multimedia Systems and Terminals (T. Geary, Conexant,
USA)Q12 B-ISDN Multimedia Systems and Terminals (S. Okubo, TAO, Japan)Q13 Packet Switched Multimedia Systems and Terminals (D. Skran, Ascend, USA)Q14 Common Protocols, MCUs and Protocols for Interworking with H.300-series Terminals (G.
Freundlich, Lucent, USA)
QUESTIONS FOR THE NEXT STUDY PERIOD
An ad hoc drafting group consisting of S. Okubo, D. Skran, T. Geary, and Y. Robin-Champigneuldiscussed issues relating to preparation of questions for the next study period. The result of thatwork is an initial draft, Annex 2 of the WP2 report (TD-59(PLEN). The plan is to provide anupdated version of the questions at the Sept. 1999 SG16 meeting, then finalize the work at theFeb. 2000 SG16 meeting. Based on the general migration toward more private packet orientednetworks which are interconnected with the present Internet, the following organization issuggested:
Potential new work areas beyond those for the current study period for SG16:
Question A: H.NewTerminalThe goal of this question is to specify a new H.xxx terminal with the following goals:
• Operate above transport layers• Used generally over IP, over all kind of physical layers (cable, xDSL, mobile, etc.)• Optionally negotiate more optimal transport mechanisms, such as H.223 or H.323 Annex C.• Operate in the same fashion in both public and private networks• Make use of H.323 infrastructure such as Gatekeepers• Would not be for either very high or very low bit rates, but would have other goals (see
audio/video/data questions).• It might or might not be fully backward compatible with H.323. A minimum goal would be
backward compatibility via a GK/MCU.
Question B: Video for H.NTThe goal of this work is to specify a new video coder, H.x264 with the following characteristics:
• Very low delay (<100 msec coder delay)• Good image performance in the range of 384 kbit/s to 1000 kbit/s• Very good robustness to packet loss, including layering methods• A general assumption is that operation in sub 384 kbit/s ranges would require H.263+ and
over 1M would require H.262.• Low complexity would be of lesser importance• Consideration should be given to the usage of object modeling techniques to achieve these ends
Question C: Audio for H.NT (G.NT)A general assumption is that a wide range of good audio coders already exist. H.NT would haveas a common set of mandatory coders G.711 and G.NT. G.4KBPS would be a major/preferredoption, or might be mandatory.
A major obstacle to the widespread usage of G.729 and G.723.1 has been the complex intellectualproperty environment. The time has come to specify a new ITU-T coder G.NT with the followinggoals:
• Either no currently valid patents are used, or the patent holders sign in advance a specialcontract stating that the specific technology offered to the ITU-T can be licensed for a nominalfee, defined as a fixed one time fee per patent. A statement to this effect will be part of eachcontribution to this question.
• Minimal complexity• Toll quality• Low delay• Robustness in the face of packet loss• Support for layering• Minimal bit rate is not critical
Question D: H.NT and H.323 (Mobile Aspects)In recognition of the importance of mobility issues, a question should be devoted to them,including terminal, user, and service mobility. This work should complement IMT-2000 ratherthan duplicate it.
Question E: H.NT (Data Aspects)This question should take a fresh look at data conferencing in the context of H.NT. Particularfocus should be placed on using web and Internet technology. This should be done as part ofH.NT rather than as a separate work item as with T.120. A key goal is total multimediaintegration.
Question F: H.NT InfrastructureThis question would look at infrastructure for H.NT and H.323, including: MCUs, GKs, GWs,including H.GCP and H.246, MIBs, Management tools and methods, including H.341 andcomments regarding work of other SGs.
Maintenance work items for the next study period may be reorganized into different Questionssuch as outlined below.
Question G: Maintenance of T.series & H.series recommendationsThis question (which might be split into two questions), would look after the on-going maintenanceof the following documents: T.120, H.320, H.321, H.322, H.310, H.324, H.224/H.231/H.243,H.224, H.242, H.244, H.221, H.223, H.226
Question H: Continuation of Q13/Q14 (H.323 & related work)This question would continue the work of Q13/Q14. Note that the older common work (Q14) isproposed to be moved to Question G (maintenance) and some of the newer work to Question F.This question would cover on-going work in: H.323, H.225.0, H.450.x, H.245, H.235. It is clearthat H.323 work will continue into at least the first half of the next study period, so this questionneeds to continue. Work has already been identified that will not be completed by Feb. 2000.
Currently image coding work spans multiple SGs with ITU. All image coding work, includingJPEG from SG14, should be moved to SG16.
WP3, SIGNAL PROCESSING
The Rapporteur for WP3 is S. F. Campos Neto (COMSAT). The agenda and work schedule forWP3/16 are in TD-24R1(3/16). The WP3 meeting report is comprised of TD-48(PLEN), TD-49(PLEN) and TD-50(PLEN).
The questions currently allocated to WP3 (and respective Rapporteurs) are:
Q15 Advanced Video Coding (G. Sullivan, Microsoft, USA)Q19 Extension to existing ITU-T speech coding standards at bit rates below 16 kbit/s (S.
Hayashi, NTT, Japan)Q20 Audio and wideband coding in public telecommunication networks (R. D. de Iacovo, CSELT,
Italy)Q21 Encoding of speech signals at bit rates around 4 kbit/s (P. Barrett, BT, UK)Q22 Software and hardware tools for signal processing standardization activities (S. F. Campos-
An ad hoc group was established under the chairmanship of A. Crossman (PictureTel, USA) todefine terms of reference for the work. TD-48(PLEN) Annex B, the draft produced, wasreviewed by WP3. A key issue is the design of new coding technology which can best exploit theproperties of wireless/IP networks to provide efficient use of bandwidth and minimize the need fortranscoding. Traditional coding technologies have not been designed to specifically meet the jointneeds of such networks. The group agreed to progress the text for the next SG16 meeting, and tohold an ad hoc meeting in September 1999. Contributions were invited on the current studytopics, in particular for the definition of application areas.
OVERVIEW OF EXISTING QUESTIONS FOR THE NEXT STUDY PERIOD
WP3 reviewed the text of the current questions allocated to WP3. Preliminary views were asfollows:
• For Q15, the work should continue for improvements in H.263 (“H.263++”) and for the newH.26L work. Both are works in progress forecast to bear fruit in 2001-2002.
• Q19 has been very active in this Study Period with the extension and maintenance of existingrecommendations. It was suggested that the work area of this question might be split into amaintenance question (possibly merging with the current Q22), and into a question dedicatedto extensions of existing standards (but not limited to bit rates under 16 kbit/s). Possible areasof activity for the latter are VAD/CNI, noise suppression, and frame erasure concealment.
• Q20 is about to complete a major milestone with the planned Decision of G.722.1 in Sep. 1999.Work remains for G.WB2, at or around 16 kbit/s, as well as for enhancement of frame erasureperformance of G.722 and G.722.1.
• Q21 should continue the current work, with views to select a 4 kbit/s codec in 2001-2002.Additionally, bitrate extensions and VAD activities should be pursued once the main ratecodec is defined.
• Q22 should continue its work on the software tool area, but discontinue activities in thehardware tools area. The latter became less important as host processing laboratoryactivities became predominantly software-based. It was suggested that the maintenanceaspect of the current Q19 might be incorporated into the continuation of Q22.
A general question was raised, as to whether frame erasure concealment techniques shoulddeserve a separate question.
Finally there was a general remark that all questions should have their background sectionupdated to reflect the need to support packet networks (IP in particular) and wireless (thirdgeneration) networks.
WP3 considered TD-36(GEN), liaison from Q4/15 on voice over xDSL, and concluded that thesystems aspects would be better addressed by Q13/16. The group felt, however, that Q4/15 couldbenefit from some general information on existing ITU-T voice codecs, as illustrated in Table 1.WP3 highlighted that the effect of delay variation, if it not properly compensated by system, isusually reflected as packet losses, which may adversely affect codec performance.
Recommendation Frame length (Look ahead) One-way delay timeG.711 Sample by sample -G.726 Sample by sample -G.727 Sample by sample -G.722* Sample by sample 3 msG.722.1* 20 ms (20 ms) 60 msG.723.1 30 ms (7.5 ms) 67.5 msG.728 0.625 ms 1.5 msG.729 10 ms (5 ms) 25 msG.4k 20 ms (15 ms)** 55 ms
* Sampling frequency is 16 kHz** This value is tentative
Table 1. Frame length and one-way delay of existing ITU-T audio codecrecommendations.
Q1/16 WP2, AUDIOVISUAL/MULTIMEDIA SERVICES
The Rapporteur for Q1/16 is Y. Robin-Champigneul (FT/CNET, France). The status report ofQ1/16 is TD-33(WP2/16). (See also the Q16-Q17/16 report, below.)
Q1/16’s meetings had to be canceled for lack of participants when it conflicted with meetings ofother Questions. However, two joint meetings took place with Q16/16 on Project M.3 (electroniccommerce) and with Q9/16 on draft Recommendation F.MCVS.
The draft revised text for Recommendation F.700, Framework recommendation foraudiovisual/multimedia services, was accepted for Determination with the proposed modificationsin TD-24(WP2/16). It contains the changes decided at the last meeting and general updating ofthe various sections. F.700 was Determined as TD-73(PLEN) and TD-74(PLEN).
WD-01(WP2/16) (Q1/16 Rapporteur) and one other working document on electronic commercewere examined; a brief presentation of electronic commerce was drafted (TD-70(WP2/16)).
The first draft of the new Recommendation F.MCVS, Multimedia conversational services, wasexamined and various amendments were made; their main purpose was to include the TotalConversation and the Text Telephony services.
The revision of the Q1/16 for the next study period was discussed and some proposals were made;in particular it was suggested to extend the scope of Q1/16 towards the general applications andpossibly towards the future architecture for the provision of services, and to add some parts ofQ2/16. It had been proposed to close Q1/16 due to the lack of contributions, but some work on thesubject is considered to be necessary, in particular taking into account the evolution in thetechnology and in the environment, and for the maintenance of the existing recommendations.
On-going work also includes revision of Recommendation F.702, Multimedia conference services;further work on Recommendation F.MRS, Multimedia Retrieval Services, is dependent uponfinding an editor.
A joint rapporteurs’ meeting with Q16/16 will be held in September 1999 on Projects M.3 and F.4(end-to-end interoperability).
Q2/16 WP2, INTERACTIVE MULTIMEDIA INFORMATION RETRIEVAL SERVICES (MIRS)
The Q2/16 Rapporteur, M. Blaschitz, could not participate in this SG16 meeting. The group,chaired by K Sambor (Post und Telekom Austria), met to review the contributions received, andto consider the closure of Question 2/16. The meeting report is TD-61(WP2/16).
MULTIMEDIA MIDDLEWARE
In the last SG16 Meeting (Sept. 1998), the workplan for the GII project M.4 (MultimediaMiddleware) was modified. The modifications are not reflected in TD-10(GEN) (Liaison fromSG10 on middleware standardization) and TD-13(GEN) (Liaison to ITU SGs on the GII project).(See also the Q16-17 report, below.)
According to the modified workplan, “Phase 2, 2.1: receive information about MM-Middlewaresolutions fulfilling the requirements,” SG10 has responded to Q2/16’s draft report on“Requirement for multimedia middleware.” However, SG10 stated that the current work onObject Definition Language (ODL) and Distributed Processing Environment (DPE) can satisfyonly a limited number of these multimedia middleware requirements. In addition, this groupwanted to state that the SG16 draft report covers only a certain part of necessary requirements,because only the following categories of multimedia systems have been considered:• Enhanced Digital Broadcast• Interactive Digital Broadcast• Institutional Multimedia Retrieval
Considering that only a certain part of the requirements are given and no new contributions werereceived, after a short discussion, Q2/16 proposed:• To accept the “Report on Middleware Standardization” of SG10 as the current status and
provide additional information to JRG on GII only if substantial new information is received.• To stop the work on M.4 in SG16, because there is not sufficient support for this work in
Q2/16.
It was agreed that maintenance of the T.170 Series recommendations should be carried out inQ1/16. These proposals were in line with the views of the Rapporteur, who was contacted bytelephone during the meeting.
Q3/16 WP2, DATA PROTOCOLS FOR MULTIMEDIA CONFERENCING
The Rapporteur for the Q3/16 is B. DeGrasse (DataBeam, USA). TD-15(WP2/16) is the report ofthe Q3/16 Rapporteur’s meeting January, 1999, in Monterey, CA. TD-16(WP2/16) is the statusreport of Q3/16. TD-57-(WP2/16) is the Q3/16 meeting report.
T.136 (EX T.RDC) AND H.282 (EX V.RDC), FOR DECISION
No contributions were received on these draft recommendations. It was noted that TD-35(PLEN) refers to the companion Remote Device Control draft Recommendation H.283. Thisdocument was reviewed and it appeared not to have any impact on T.136 (Remote device controlapplication protocol) or H.282 (Remote device control protocol for multimedia applications). It wasagreed that T.136 and H.282 should be submitted for Decision.
T.MRM (MEETING ROOM MANAGEMENT), FOR DETERMINATION
TD-19(WP2/16), Draft Rec. T.MRM (Meeting Room Management) was reviewed. ThisRecommendation provides extensions to the Generic Conference Control (T.124) functionality to
support the specification and management of virtual meeting spaces (meeting rooms) within aconference. This work is expected to find application in the provision of commercial audio-graphics conferencing services.
Procedures are defined for arbitrating use of real time media services such as telephony, foradvertising those services to participating nodes and for managing and controlling those servicesonce they are activated. These services include the following:• Virtual meeting rooms - creation, entering, leaving, destroying• MRM management roles - convener, chair, secretary, and user defined• MRM framework• Audio management - mixing, channels• Groups• Channels and token
T.MRM also defines a Conference Server that takes responsibility for the running of the MRMConference and a service access channel for communication between the clients and server.T.MRM was Determined by SG16 as TD-7(PLEN).
T120 IMPLEMENTORS GUIDE UPDATE
The T120 Implementors Guide was updated and approved by SG16 as TD-6(PLEN). It containsinformation regarding T.120 (Data protocols for multimedia conferencing), T.124 (GCC) andT.127 (Multipoint binary file transfer protocol) Recommendations as indicated below:
• T.120: Table of the MCS static channel assignments for GCC, SI (Still Image), MBFT(Multipoint Binary File Transfer), Application Sharing and Chat Recommendations.
• T.124: Comments and ASN.1 modifications for Unicode support of conference names andpasswords.
Draft Rec. SG16 May 1999 Next SG16 Feb. 2000T.123 Rev DT.136 (T.RDC) DH.282 (V.RDC) DT.MRM d D
(d = Determine, D = Decide)
With the completion of work at this meeting, Q3/16 feels that sufficient specification is now inplace to support the present generation of data conferencing. This body of work will support thedevelopment and continuing growth of data conferencing in conjunction with out-of-band audioconferencing. The need for this style of conferencing will continue until sufficient bandwidth andquality of service is available to support fully integrated multimedia solutions on IP networks.
Q4/16 WP1, MODEMS FOR SWITCHED TELEPHONE NETWORK AND TELEPHONE TYPE LEASEDLINES
The Rapporteur for Q4/16 is B. Adams (Motorola), previously with Hayes. TD-13(WP1/16) isthe agenda. TD-11(WP1/16) is the report of the interim Q4/16 meeting in San Diego, California,USA, December, 1998.
TD-6(GEN), a liaison statement from SG4 requesting information on multimedia managementactivities, was discussed. As Q4/16 has undertaken V.mmo, managed objects for modemdiagnostics, it was decided to inform SG4 of this work as it is related to their work. A responseliaison was approved (see TD-44(PLEN)).
TD-1(WP1/16), a liaison statement from SG8, concerns a recent problem seen with V.21modulation and network echo cancellers. During the discussion of this issue, it became clear that
this problem could have far-reaching implication for many devices using V.21 without disablingnetwork echo cancellers. This problem appears in part to be caused by a new generation of echocancellers which notch out one of the frequencies in the high band of V.21 (a modulation used inV.8). Therefore an informative note was approved for inclusion in Recommendation V.8suggesting use of the phase reversal option of ANSam to disable echo control devices (TD-39(PLEN)). An outgoing liaison to SG8 informing them of this action (WD 1-05) was approved.
TD-44(PLEN) provides the liaison to inform SG15 of the V.21/V.8 problem and requests SG15look into this phenomenon and report back their findings. Q4/16 also asked that SG15 copy themon any replies made to SG8 regarding this issue.
It was noted that Recommendation T.35 has been revised requiring a change to the non-standardfacilities section of Recommendation V.8, because T.35 country codes may now contain more thanone octet.
The references section was updated to include Recommendation V.91 and the revision toRecommendation T.35.
All the changes to Recommendation V.8, as contained in TD-39(PLEN), Addendum toRecommendation V.8, fwas Decided by SG16.
facilities section of Recommendation V.8bis because T.35 country codes may now contain morethan one octet.
• The references section of V.8bis has been updated to reflect these changes as well. All thesechanges are shown in TD-40(PLEN), Implementors Guide to Recommendation V.8bis.
V.MMO - MODEM MANAGED OBJECTS
Due to the changing employment circumstances of the Rapporteur, the stated goal ofDetermination for V.mmo was not achieved at this meeting of SG16.
TD-17(WP1/16) is a re-presentation of a Q4/16 document presented in San Diego, December1998, which proposes additions to V.250 for the use of V.mmo. Since this document addressesadditions to Recommendation V.250, this item was forwarded to Q7/16 for further consideration.
As no further contributions concerning the proposed V.8lite project were received, V.8lite wasdropped as a work item.
Q5/16 WP1, ISDN TERMINAL ADAPTERS, AND INTERWORKING OF DTES ON ISDNS WITH DTESON OTHER NETWORKS
J. Moughton (UK) was the Rapporteur of Q5/16, however, he has changed companies and can nolonger participate as Rapporteur. J. Magill (Lucent, UK, WP1/16 chair) chaired the meeting.The meeting report is included in the WP1 report, TD-42(PLEN).
INCOMING LIAISON STATEMENTS
TD-2(WP1/16) from SG11 concerns codepoints in Q.931 “Modem type” field of the Bearercapability and Low layer compatibility information elements, and informs SG16 that fourrequested codepoints (V.90 analog, V.90 digital, V.18 and V.32bis) have been inserted in Q.931,and related clarifications added. No further action is proposed at this time.
TD-10(WP1/16) from ISO/IEC JTC1 provides the text for ISO/IEC DTR 10171 “List ofStandard Data Link Layer Protocols that Utilize High-Level Data Link Control (HDLC) Classesof Procedures and List of Standardized XIC Format Identifiers and Private ParameterIdentification Values.” This is relevant to Q5/16 in that it includes Recommendation V.120. Itwas noted that the deadline for immediate comment had already passed, so delegates wereinvited to study the document further and bring any comments to the next meeting of SG16.
TD-3(WP1/16) is a liaison from ISO/IEC JTC1/SC6/WG3 noting that, because there are no DTEmanufacturers in SC6/WG3, they cannot comment on the proposed changes to V.24. TD-
44(PLEN) provides a return Liaison Statement describing the Determined version of V.24 fromthis meeting.
The Rapporteur plans to attend the next SG7 meeting (June 7-17, 1999 in Geneva) to discuss theproposed transfer of responsibility for interface-related Recommendations X.20, X.20bis, X.21,X.21bis, X.24 and X.150 from SG7 to SG16. TD-20(WP1/16) is the liaison to SG7 noting this.
Q7/16 WP1, DTE-DCE INTERFACE PROTOCOLS
The Rapporteur of Q7/16 is F. Lucas (3Com, USA). TD-26(WP1/16) is the agenda. Theobjectives of this meeting were to review Recommendation V.250, which was for Decision at thismeeting, to consider future V.250 commands in support of V.mmo, and to consider future work onV.25i, draft Recommendation for ISDN TA commands.
INCOMING LIAISON
TD-22(GEN), a liaison from SG2 Q1/2, asks if a proposed change to Recommendation E.164would cause changes to Recommendation V.250. Q1/2 is considering a change to E.164 whichwould increase the County Code format from 3 to 4 digits. Q7/16 reviewed V.250 and concludedthat no change would be necessary in V.250 as a result of the proposed change to E.164. TD-44(PLEN) contains the return liaison to Q1/2 informing them of this.
The group was made aware of a recent change to Recommendation T.35 which could cause achange to the +GCI command. It was agreed that until such time as the revised T.35 is availableno change should be made to V.250. This could be included in a future V.250 ImplementorsGuide.
ADDITIONAL V.250 COMMANDS IN SUPPORT OF V.MMO
TD-17(WP1/16) proposes possible V.250 commands to support V.mmo (modem managedobjects). The Q4/16 Rapporteur indicated that the structure of V.mmo has changed since thisdocument was created. As a result, the proposed commands would require some modificationswhen V.mmo is finalized. (See the Q4/16 report above for additional information on V.mmo.)
J. Moughton, the editor of the new draft Recommendation V.25i, ISDN TA Commands,unfortunately had to resign the position. Q7/16 expressed its appreciation to J. Moughton for hiswork on this draft Recommendation. Q7/16 considered the future of this work and concludedthat, from a practical viewpoint, this Recommendation was no longer needed, so it was agreedthat work on V.25i would be terminated.
FUTURE OF Q7/16
The group considered the future of Q7/16 for the next study period. Considering that theworkload in Q7/16 is greatly reduced, the group recognized that a consolidation of Questions wasa logical step.
The acting Q8/16 Rapporteur was J. Magill (Lucent), as B. Pechey (UK), the Rapporteur, couldnot attend.
Q8/16 considered one incoming liaison statement, TD-10(WP1/16), from ISO/IEC JTC1, whichprovides the text for ISO/IEC DTR 10171 “List of Standard Data Link Layer Protocols thatUtilize High-Level Data Link Control (HDLC) Classes of Procedures and List of StandardizedXIC Format Identifiers and Private Parameter Identification Values.” This is relevant to Q8/16in that it includes Recommendations V.42 and V.75. It was noted that the deadline for immediatecomment had already passed, and so delegates were invited to study the document further andbring any comments to the next meeting of SG16.
A Liaison Statement (contained in TD-44(PLEN)) was generated informing ITU-T SG7, 9 and15 as well as IEEE, IETF, ITU-R and ETSI of the new work item on data compression andinviting comments on requirements.
Preliminary discussions identified the need for the following work items:• Update the “test files” to include typical Internet traffic - for completion at the first interim
meeting• Define algorithm selection criteria on issues such as:
- Compression ratio (improvement over V.42bis)- Complexity (MIPS & memory)- Code re-use with V.42bis- Improved functionality over V.42bis, e.g. accommodation of other character lengths- Algorithm learning ability- Latency
• Liaison with other bodies for the purposes of collecting “requirements” information
Additionally the following agreements were reached:• The deadline for submission of candidate algorithms shall be the February 2000 meeting of
SG16;• The resulting Recommendation shall define the algorithm mathematically in text and shall not
include normative c-code;• Companies proposing algorithms shall make c-code implementations available for evaluation
purposes to any interested ITU-T member.
Q9/16 WP1, ACCESSIBILITY TO MULTIMEDIA FOR PEOPLE WITH DISABILITIES
The 9/16 Rapporteur is G. Hellström, (Ericsson, Sweden). TD-25(WP1/16) is the agenda. TD-29(GEN) is the Q9/16 status report. In addition to the Q9/16 meeting, the experts of Q9/16participated in joint sessions with other groups.
Question 17/2 liaison TD-9(WP1/16) contains answers to Q9/16’s earlier liaison to Q17/2. Itcomments on the efforts of Q1/16 and Q9/16 to establish a service description for multimodalconversation - Total Conversation. It notes their concern that terminals for multimodal servicemay be complicated to operate. Experience from Total Conversation implementations appears tocontradict this concern.
The liaison also comments that Total Conversation terminals may be expensive. That may beinitially true, but should not hold Q9/16 back from completing a service description. Q9/16 willencourage Q1/16 to continue work on conversation services including text, video and voice.
V.18 AND H.324 IN MULTI FUNCTION TERMINALS (V.8 AND V.8BIS, WITH Q4/16)
There was much discussion in the last SG16 meeting on small deficiencies in V.8bis that makes ithard to design devices with both V.18 and H.324 functionality. Clarifications were expected tothis meeting, but no contributions have been received. This should be a joint issue with Q4/16.
MULTI MODAL CONVERSATIONAL SERVICE DEFINITION CONTAINING VIDEO, TEXT AND VOICE, (F.MVCSWITH Q1/16)
Q1/16 has now put priority on the work with conversation service descriptions F.MVCS. In ajoint meeting, a draft multimedia conversation service description was reviewed. Details forTotal Conversation, video requirements for sign language and lip-reading and for text telephonywill be proposed by the Q1/16 rapporteur assisted by Q9/16. The goal is Determination inFebruary 2000.
An unresolved problem was uncovered with some plain Minitel terminals (the NON text telephonetypes of Minitel). There is a need to modify the XCI signal of V.18, but there is not yet a firmproposal. The current XCI does not stimulate all Minitels to respond. This has been reported ina problem report.
The Rapporteur announced that he has an agreement to continue this task on behalf of LMEricsson until Feb. 2000. No commitment for following period can be given at this time. Thegroup agreed that a continuation of actions for accessibility to multimedia for people withdisabilities is important and should be proposed to the study group planning.
A supportive letter from Gallaudet University (a university for audio impaired students in USA)commended the work done by SG16 and announced the university’s intent to contribute to thework.
Current work items are:1. Completion of text conversation in H.323 (See Q13/16 report, H.323 Annex G)2. Completion of text conversation in H.320 (See Q11 report, H.320 Determination)3. Completion of Sign Language and Lip Reading application Profile document4. Maintenance on established text conversation modem Recommendation V.18, and related
V.8bis, V.8 and V.25x. A revision should be produced soon.5. Maintenance of text presentation protocol T.140.6. Conversation service definition containing Video, Text and Voice F.MVCS (with Q1/16).7. End to end interworking of Total Conversation including Video, Text and Voice (with Q14/16)8. Any other accessibility issue (e.g., IMT-2000) related to SG16 issues
Q10/16 WP1, MODEM TESTING
The 10/16 Rapporteur is G. List (Austria). The meeting report is included in TD-42 (PLEN).
TD-5(WP1/16) is a liaison statement from SG15 on “network characteristics” for information.Two major points are addressed: CME (circuit multiplication equipment) from Q6/15, andInterworking from Q8/15. (See Q23/16 report, below.)
As, during the study period, contributions to Q10/16 were received only from the USA, the Chairsuggested that Q10/16 does not need to continue into the next study period. Considering thereorganization of WP1, it was suggested that a study item be added to one of the new questions,so that contributions on modem testing can still be addressed. This was agreed.
Q11/16 WP2, CIRCUIT SWITCHED NETWORK (CSN) MULTIMEDIA SYSTEMS AND TERMINALS
The Rapporteur for Q11/16 is T. Geary (Conexant, USA). TD-14(WP2/16) is the report of theQ11/16 Rapporteur’s meeting, November 1999 in Torino, Italy. TD-27(WP2/16) is the report ofthe Q11/16 Rapporteur’s meeting, February 1999 in Monterey, CA. TD-26(WP2/16) is thestatus report of Q11/16. TD-65(WP2/16) is the Q11/16 meeting report. The informal Q11/16reflector is <[email protected]>.
Q11/16 met with the following objectives:• Review the proposed changes to draft text for revision of H.320, H.221, H.230, H.242, H.243
and H.224• Changes to proposed text for H.223 Annex D• Review of proposed changes for addition of MPEG-4 visual standard in H.245v5• Discussion of inclusion of MPEG-4 System capability in H.324/H.245• Discussion of inclusion of MPEG-4 Audio capability in H.32x• Discussion of inclusion of non-ITU-T codecs in H.3xx and H.245• Multilink functionality for H.324 Mobile terminals• Review of proposed revisions to the Implementors Guide for H.324 and H.223• Discussion on the proposed future activities and SG organization with Q1, Q3, Q12, Q13, Q14
TD-8(WP2/16) and TD-9(WP2/16) were superseded by TD-10(WP2/16). These liaisons are allfrom ISO/IEC JTC 1/SC29 and relate to MPEG-4 support in H.324 systems. TD-10(WP2/16)supports the proposed generic format mechanism and associated Annexes. (See Q11-14/16reports below for additional details.)
H.223 Implementors GuideTD-46(WP2/16) is the incoming draft H.223 Implementors Guide. It provides a compilation ofreported defects with the 1997-2000 editions of H.223. Sg16 approved the H.223 ImplementorsGuide as TD-15(PLEN).
H.320 SYSTEMS (H.224 AND H.243), FOR DETERMINATION
TD-32(GEN) proposes revision of H.224 (A real time control protocol for simplex applicationsusing the H.221 LSD/HSD/MLP channels) in support of Text Conversation in H.320 terminals.It was agreed in the joint Q/11-14 meeting. SG16 Determined the proposed draft revision ofH.224 as presented in TD-11(PLEN). (See Q14/16, H.224, below.)
SG16 Determined the proposed draft revision of H.243 presented in TD-20(PLEN). (See theH.320 Systems report, above.)
Q11/16 reviewed the proposed draft text to be added to H.245v6 in support of MPEG-4 Audio(ISO/IEC 14496-3). The group noted that the final text for inclusion in H.245v6 should utilizegeneric capabilities; that text is included in TD-22(PLEN). It was given to Q14/16 to include inH.245v6 for Determination.
Q11/16 reviewed the proposed draft text to be added to H.245v6 in support of MPEG-4 Systems.The group noted that the final text for inclusion in H.245v6 should only make reference to genericcapabilities and the sections requesting the addition of codepoints directly in H.245 should bedeleted. With this change and alignment of syntax with the new generic capability sampledefined in H.245v5, the group approved TD-14(PLEN), and requested Q14/16 to include it in theproposed draft text for H.245v6 for Determination. (See Q14/16 H.245v6 report, below.)
does not guarantee synchronized delivery to support such layered coding schemes. Q11/16agreed to take this item under study for possible addition to future revisions of H.324 and H.245.
OUTGOING LIAISONS
TD-62(WP2/16) is a liaison to ISO/IEC noting that Q11/16 and Q14/16 have supported theproposals from ISO/IEC JTC1/SC29/WG11 on the MPEG-4 inclusion in H.324 and H.245.
Q11/16 WORKPLAN
Table 2 present the Q11/16 workplan.
Item Editor Schedule Status CommentH.245v6 M. Nilsson, UK 2/00 For Decision Support to Q14/16H.243 (revision) P. Luthi, USA 2/00 For Decision Support to Q14/16H.224 (revision) M. Nasiri, USA 2/00 For DecisionH.324 AnnexMPEG-4 System
J. Vollmer, Germany 2/00 For Decision
H.mml G. Roth, Sweden 11/00 In work see Q13, H.323 mobileannex future work
H.32L Not yet assigned 2003 Under study Joint with Q11, Q12, Q13,Q14, JQG1/11, ITU-RTG8/1
Table 2. Q11/16 Workplan as of May 1999.
WORK ITEMS FOR THE NEXT STUDY PERIOD
The following items of work are envisioned going forward within Q11/16:
1) Work on terminals to support IMT-2000 network (“Media 2000”) as it relates to the networkarchitecture of 3G wireless and GII in general
2) Support the work on higher quality lower delay audio and video codecs for multimediaapplications
Q12/16 WP2, B-ISDN MULTIMEDIA SYSTEMS AND TERMINALS
The Rapporteur for Q12/16 is S. Okubo (Telecommunications Advancement Organization,Japan). TD-32(WP2/16) is the report of the Q12-14/16 interim Rapporteur’s meetings(November 1999 in Torino, Italy, and February 1999 in Monterey, CA). TD-31(WP2/16) is thestatus report of Q12/16. The Q12/16 meeting report is TD-59(WP2/16).
Q12/16 met with the following objectives:• Decision of H.222.0 | ISO/IEC 13818-1 Amendment 5 and Amendment 6• Determination of H.222.0 | ISO/IEC 13818-1 Amendment 7• Discussion on other technical items• Discussion on future direction including the questions for the next study period
H.222.0 | ISO/IEC 13818-1 AMENDMENT 5, FOR DECISION
H.222.0 | ISO/IEC 13818-1 AMENDMENT 7, FOR DETERMINATION
TD-29(WP2/16) (Q12/16 Rapporteur) proposes a new Amendment 7 to H.222.0 | ISO/IEC13818-1, Information technology - generic coding of moving pictures and associated audioinformation: video, to carry ISO/IEC 14496 (MPEG-4) content over H.222.0 | ISO/IEC 13818-1(MPEG-2) System streams. Q12/16 confirmed that there is no direct impact on H.310 at thismoment. If any market need is identified, H.310 will be amended with a description of how to useMPEG-4, referring to this Amendment 7 to H.222.0. It was pointed out that addition of H.245codepoints for MPEG-4 coding is on-going and H.310 can use them. With the clarification above,SG16 Determined H.222.0 | ISO/IEC 13818-1 Amendment 7 as TD-23(PLEN).
TECHNICAL ISSUES
Issue of Integrated Edition For Common Text RecommendationsTD-28(GEN), Integrated edition of ITU-T Recommendation H.222.0 | ISO/IEC 13818-1(Amendments 1-7 and Corr. 1) and ITU-T Recommendation H.262 | ISO/IEC 13818-2(amendments 1-6 and Corr. 1 and 2) from the Q12/16 and Q15/16 Rapporteurs, was presented atthe joint WP meeting. It was confirmed that there is no need for additional procedures forintegrating already approved texts with minor editorial amendments. TD-38(GEN) is theliaison statement to MPEG providing the approval of SG16 to publish the joint textRecommendations. (See also Q15/16 report, below, re: H.262.)
H.321 Implementors GuideTD-13(WP2/16), DSS2 protocol provision of adaptive timing recovery used for transmitting clock(Q20/SG11), had been discussed at the Monterey Rapporteurs meeting (February, 1999, CSRVol. 10.3). TD-30(WP2/16) provides draft text for the H.321 Implementors Guide. Q12/16agreed to the text, which should be approved at the next SG16 meeting after Decision of theQ.2931 revision by SG11 (expected December 1999).
End Station Identifiers of H.310 and H.321TD-12(WP2/16) (SG11) indirectly indicates that the definition of end station identifier in DSS2information elements had been finalized in Q.2941.2. SG11 provisionally agreed on theassignment of codepoints within the GIT (generic identifier transport) information element inorder to transfer the 16 bit port number to identify an RTP stream. In response to this, Q12/16should produce texts for the H.310 and H.321 Implementors Guides. This will be worked outbefore the next meeting with confirmation of the Q.2941.2 status.
LIAISONS
TD-16(GEN) (SG13) is the multimedia coordination “Status of Activities.” Q12/16 agreed thatH.310, H.321, and H.247 should be included in the Q12/16 entry of the “status of activities”table.
WORK PLAN
Table 3 presents the Q12/16 Workplan. Q12/16 future work includes:• Incremental improvements to and maintenance of existing Recommendations; H.310, H.321,
H.247, H.222.0, H.222.1• High quality audiovisual services over the packet based (IP) network jointly with Q13/16
Study subject Editor Det. Dec.H.222.0 | ISO/IEC 13818-1 Amendment 7 S. Okubo (TAO, Japan) 05/99 02/00H.321 v2 Implementors Guide S. Okubo (TAO, Japan) - 02/00H.310 v2 Implementors Guide K. Sakai (Fujitsu, Japan) - 02/00Security for broadband systems {solicited} TBD TBDVBR aspects M. Nilsson (BT, UK) TBD TBDH.246 Annex (Broadband systeminterworking)
{solicited} TBD TBD
High quality video transmission over IPincluding MPEG-2 packetization (withQ13/16)
{solicited} TBD TBD
Table 3. Q12/16 Workplan as of May 1999.
Q13/16 WP2, PACKET SWITCHED MULTIMEDIA SYSTEMS AND TERMINALS
The Q13/16 Rapporteur is D. Skran (Ascend). TD-32(WP2/16) is the report of the Q12-14/16interim Rapporteur’s meetings (November 1999 in Torino, Italy, and February 1999 in Monterey,CA). TD-44(WP2/16) is the status report of Q13/16. TD-23(WP2/16) is the agenda for thismeeting. TD-66(WP2/16) is the Q13/16 meeting report.
LIAISONS
TD-4(WP2/16), Support of IN services for H.323 and other IP Network-based terminals (SG11),presents the work that SG11 Q5 has done on the requirements for functional architecture (usingPINT servers) in support of IP networks. Q13/16 produced a draft liaison (WD2-06) which notesthe differences between the SG16 and SG11 (TIPHON-based) architectures and proposes acombined architecture. Due to the complex nature of the issues involved, it was agreed to defer aresponse until the next rapporteurs meeting.
TD-5(GEN) notes that Q9/11 is beginning work on a new recommendation (Q.ELINT) definingecho control logic for voice calls via an internet. Because of the time varying nature of aninternet (IP network), network-based echo cancellers will not work and echoes must be canceledlocally. Q.ELINT is intended to be used in harmony with Q.115, Logic for the control of echocontrol devices in telephone networks. The Rapporteur is L. Forni (Lucent Technologies). Q13/16prepared a return liaison (WD2-17) noting the work being done in SG16 on echo control.
TD-22(GEN), Study of the expansion of the Rec. E.164 country code format to 4 digits(SG2/WP1/Q1), anticipates exhaustion of 3 digit country codes in 10-15 years. Q13/16 noted thatthis would affect H.225.0v3/H.323v3; Q13/16 must examine the support for 4 digit country codesin the H-32x related documents. The editor for H.323 reported that H.225.0 and H.245 will notbe affected by this change. Other H-Series documents inherit definitions from H.225.0.Currently, all E.164 numbers are contained in an IA5String that is of size 1..128.
TD-23(GEN), Liaison relating to IMT-2000 Numbering (Chair WP1/2), will be considered aspart of on-going work.
TD-36(GEN) is a liaison on Voice over xDSL from Q4/15. The Q13/16 rapporteur will write aliaison with information related to topics such as data rate, number of channels of voice, etc.; italso will address H.323 Annex C if ATM is used over xDSL. Lifeline service is not critical as it isassumed to be provided at a lower lever. The number of channels should be a user-level trade-off.A major decision is “Looks like a LAN” vs. “Looks like ATM” vs. “Looks like ISDN.” It was notedthat PPP over ATM obscures the ATM features. SG15 maintains a series of recommendations onvoice quality, and ETSI TIPHON does also at the applications layer (TR 101 329). P. Barrett ofWP3 is also preparing a liaison. This liaison appears with the meeting report (TD-66(WP2/16)).
continue to work toward clarifying this point, but perhaps with an alternative mechanism.• Registration with a gatekeeper that is not permanent: Also not accepted; further contributions
The editor for H.323 reported that currently the ASN.1 has one byte for the country code and onebyte that is a “T.35 extension assigned nationally.” The H.323 editor believes that this is notcompliant with the new T.35 and that changes are necessary in the next revision of H.225 andH.245 to correct this problem.
The introduction of the Fast Connect procedure into H.323v2 provided a means of allowing mediachannel establishment at the earliest point in a call. More recent developments have suggestedexpanding the scope of this procedure to be allowed at any point in a call, thus evolving into amechanism that fully parallels H.245 Open Logical Channel (OLC) signaling. The advantage tosuch an evolution is that it permits endpoints to dispense with H.245 signaling, both viatunneling and via separate connection. A disadvantage is that endpoints implementing the FastConnect procedures must normally also support H.245 signaling for a variety of reasons, inwhich case they must support two different semantic interpretations of the OLC structuresdepending on the means of transport. This is an undesirable burden on endpoints which presentsfew benefits. This concept was supported:
Section 2 (Logical channel alternatives): Will become an informational appendix of H.323v3.Section 3 (Open logical channel signaling procedures): This was not accepted.Section 4 (Transport addresses): The change to H.323 section 8.3 was accepted, with a small
modification, as was the change to H.245v3 section 7.3.2. It was also agreed to accept thechange to H.245v3 section 7.3.1.
TD-54(WP2/16) (corrected version in WD2-08) is the Implementors Guide for the ITU-T H.323,H.225.0, H.245, H.246, H.235, and H.450 Series Recommendations - Packet-BasedCommunications Systems.
A number of small changes were made. (See also Q13 H.225v3, below.) With these changes theH.323, H.225.0, H.245, H.246, H.235, and H.450 Implementors Guide was approved by SG16as TD-37(PLEN) plus TD-56(PLEN).
It was noted that port 2517 was named “signaling transport” and this should be changed by theeditor to “h323annexE.” This was agreed. It was noted that we should investigate possible ITU-T ownership of these ports. It was noted that this port and all the other H.323 ports aretechnically not “well known ports” but are actually “registered ports.” This will be investigatedby the editors. RFC 1700 is the relevant reference.
expressed that request mode needed to be combined with replace mode to create a clean switch.It was noted that a code would be needed to identify T.38 in RTP, or some examination of the datastream. This will be further developed for possible inclusion in H.323v3.
TD-1(WP2/16), Recommendation T.38 Indications in Recommendation H.245 (SG8), notes errorsin the ASN.1 encoding in H.245. It was agreed (jointly with Q14/16) that:1) A true error has occurred.2) The T.38 facsimile profile in H.245 should correspond to the actual profile as specified in T.38
Annex B.3) Q13/16 will investigate whether this raises any interoperability issues.
TD-3(WP2/16), Draft T.38 Appendix II: Call Sequence Examples using T.38 Annex B (SG8),requests Q13/16’s review of some interoperability message sequences. WD2-19, Q13/16 liaison toSG8, identifies four corrections; WD2-18, T.38 Appendix II with change marks, attached to it.
TD-6(WP2/16), Additional Questions Regarding T.38 Annex B (SG8), contains the final T.38Annex B, and a SG8 liaison related to it. SG8 raises concerns about the difficulty firewalls willimpose on T.38 Annex B devices, particularly Internet access facsimile devices, and proposessome solutions using a “well known port.”
Proposals on the following topics are solicited for the August rapporteurs meeting:• The assumptions held by an endpoint about the relationship between a GK and its backup• How this might affect switching in the protocol
Sections 1 through 4 propose that the initial dialed number in two stage dialing be passed to theGK. Discussion on Sections 1 through 4 was inconclusive.
WD2-12 is a more refined proposal, from the Q13/16 Rapporteur, for a “Generic ServiceTransport Channel” that would transport CPL as well as WAP in a general fashion. This will bedeveloped further with two goals: 1, A possible appendix or annex to H.323, and 2, Small ASN.1changes to H.323v3 to support this channel.
It was agreed to add a new method such as one of those mentioned here:• Add percent capacity remaining to BRQ/DRQ.• Report an array of capacity levels for each media type.
It was agreed to add some method of reporting more detail on GW call capacity to the GK toH.323v3.
• G.729 should not be required for compressed voice in RAS messages.• AnnIdentifier should have a repeat and an off time.• This proposal is complementary to the usage of a large announcement server distinct from the
GW.• The study should cover a separate announcement server.• Transport via RAS was not a good idea due to message size limits.• A URL should allow the GW to talk to a variety of servers to get announcements.• The interaction between the GW/GK should be extended to include more exchanges.• Video announcements and conversational text announcements should be included.• A need exists to apply announcement during a call at any time, and to control their direction.
• Compressed voice should not be passed via RAS.• It is important for the GK to control the playing of announcement and related matters, but in a
higher level fashion than in this proposal.• Provision should be made for at least two architectures:
- Announcements in the GW- Announcements in a separate announcement server- Consideration should be given to announcements in terminals
Overall, it was agreed that the control of announcements is a valid work item for H.323v3.Consideration should also be given to coordination with H.GCP.
It was noted that this protocol is not intended to be used over very long ranges as humanresponse times are involved. It was also noted that a strict following of a pure stimulus model isnot required or even a good idea. A clear requirement is that adding a new service shall notrequire (generally speaking) an upgrade to the client. Application to SETs will be considered.
The following comments were raised:• CNG (calling tone) appears in data modems in Europe, and cannot be used as a marker for a
fax modem.• Coordination of data rates is required.• How long should the data be buffered?• Is V.42 end to end or link by link?• How is data compression negotiated?• Is speed negotiated end to end, or link by link? A view was expressed that the link-by-link
would give better results.• How is modem re-negotiation handled?• Is it clear that V.90 is even possible in this configuration? (Some say yes.)
- There are flow control issues, with V.90 downstream and V.34 upstream.- There may be a way around this (from A. Draper, Madge).
• What about synchronous vs. asynchronous modem?• Break handling end to end needs to be confirmed.• The relationship to text telephony was raised.
It was suggested that UDP should not be used for a variety of reasons. Consideration should begiven to usage of any existing RFCs. The usage of TCP is a key assumption of this work.
It was agreed that this work should be pursued. It was noted that an H.246 H.323 to PSTNannex might be a place for this work. It was suggested that the work should be joint betweenQ23/16, Q13/16 and Q14/16. The terms of reference will be worked via correspondence betweenthe respective experts’ meetings. The target is Determination in Feb. 2000, with most probablyan H.323 Annex and possibly a Q23/16 document.
H.450.8, CONFERENCE OUT OF CONSULTATION, FOR DETERMINATION
TD-18(WP2/16) is draft Recommendation H.450.8. It was agreed to withdraw this fromDetermination, and to incorporate the features of H.450.8 into the main text of the DeterminedH.323v3, as section 8.4.3.8. This text appears as WD2-16.
H.450.9, CALL COMPLETION ON BUSY SUBSCRIBER, FOR DETERMINATION
It was agreed to not Determine H.450.9 (Call Completion on Busy Subscriber) at this meeting;volunteers are solicited to continue this work.
H.450.10, NAME IDENTIFICATION SERVICES, FOR DETERMINATION
TD-51(WP2/16) is draft Name Identification Services (Editor G. Freundlich, Lucent). It wasDetermined by SG16 as H.450.8 rather than H.450.10, as the original H.450.8 was withdrawn,and incorporated into H.323v3. Final text is in TD-30(PLEN).
WD2-03 contains a proposed H.323 Annex F for a security SET based on the IMTC securityprofile and also on similar ETSI TIPHON work. There are no new changes with respect toH.235. It was not agreed to recommend Determination. M. Euchner (Siemens) will be the editor.
H.323 ANNEX G, TEXT CONVERSATION AND TEXT SET, FOR DETERMINATION
In H.323 multimedia systems, a text conversation transport for T.140 is in preparation in theform of a channel set up by H.245. The additions to H.323, formed into H.323 Annex G, TextConversation, were up for Determination at this meeting. This Annex G also contains a simple IPtextphone description called “Text SET,” based on the principles from H.323 Annex F.
It was agreed during the joint meeting with Q11/16 to create a mobile Annex for H.323. Thiswould take the form of a document or documents that address mobility issues, including:
• Mobility, including user and service mobility• Mobile issues including
- Layer 2 issues & timers- Header compression- Handoffs and the H.323 system architecture
A general goal is to apply H.323 systems to mobile systems being defined elsewhere, such asIMT-2000. This annex would consider the possibility that a packet layer other thanTCP/UDP/RTP might be used for mobile applications. The tentative plan is to work toward aFebruary 2000 Determination.
Q14/16 WP2, COMMON PROTOCOLS, MCUS AND PROTOCOLS FOR INTERWORKING WITHH.300-SERIES TERMINALS
The new Q14/16 Rapporteur is G. Freundlich (Lucent, USA). TD-32(WP2/16) is the report of theQ12-14/16 interim Rapporteur’s meetings (November 1999 in Torino, Italy, and February 1999in Monterey, CA). TD-47(WP2/16) is the status report of Q14. TD-69(WP2/16) is the Q14/16meeting report.
LIAISONS
TD-1(GEN) reports on SG4, the lead SG for Telecommunications Managed Networks (TMN);SG4 maintains the Documentation Plan (Attachment 2 of TD-1(GEN)). TD-6(GEN) from SG4provides M.3010-1996 which describes the TMN architecture and layering approach.Management layers are: business management, service management, network management andnetwork element management. Also attached to TD-1(GEN) is M.3400-1997 which describesTMN management functions and function sets. Management functions are categorized into: fault,configuration, accounting, performance and security. The reply (WD2-21) contains responses tothe specific questions in the liaison, and describes the relevant work in H.341, H.235, andH.225.0 Annex G.
TD-2(WP2/16), Media Gateway Control (Q4/8), indicates problems with fax support in theproposed IETF MGCP protocol. The response, WD2-23, mentions the H.GCP work in SG16, butstates that comments on IETF protocols should be sent to the IETF. The suggested requirementsfrom the liaison will be added to the requirements maintained by the IETF MEGACO group(these requirements serve as a basis for H.GCP work). A draft of H.GCP will be attached toWD2-23.
TD-11(WP2/16), Response to Liaison Statement from SG16 Regarding the H.323 MIB and TMN(WP5/4), describes some management work in SG4 Working Party 5, and requests information onthe H.341 (media management) work. The response, WD2-22, includes an early draft of theH.341 work (April 1998).
The Implementors Guide for H.323, H.225.0, H.245, H.246, H.235, and H.450 was approved bySG16 as TD-37(PLEN) and TD-56(PLEN). (See also Q13/16 Implementers Guide, above.)
The third requirement is for the protocol to support H.245 in the media GW. This request wasaccepted.
The final requirement, for the protocol to support call by call mode switching, was also accepted.It was noted that this requirement might also apply to other types of mode changes.
A number of issues were identified that required resolution:
• Multimedia vs. linked mono-media contexts: The so-called connection model for the mediagateway affects the definition of the protocol. The decomposed gateway must supportmultimedia, so modeling multimedia support is a critical issue. A breakout group was formedto address this issue. The results appear in TD-58(WP2/16), and have been incorporated intothe draft text. It was agreed to use the multimedia context model proposed by J. Segers(Eindhoven University of Technology), with some extensions and amendments. TD-58(WP2/16) also includes the proposal from B. Rosen (FORE Systems) for linking mono-mediacontexts to create a multimedia context model for H.GCP.
• There is a need to express a media gateway’s capabilities and to describe, on a per call basis,the coders and addresses used. Current ideas include a modified SDP or something that canexpress the description capabilities found in H.245 (though not strictly H.245). This needsfurther work.
• Encoding: Possibilities appear to be binary (e.g., similar to Q.931), text, or ASN.1. This is anissue that can be left until later.
• Semantics of terminations: There is some concern that the “termination” object cannotadequately model the various types of endpoints/users (e.g., DS0 vs. a multiplex such as H.221vs. bonded DS0, etc.). Some resolution was reached. Text appears in the H.GCP draft. Textto define the concept of a multiplex needs to be added to the definition of a termination.
• Termination class: The termination classes should be defined. A preliminary superset ofparameters exists in the document, but specific termination classes are needed.
Draft H.GCP discusses required and optional support for the signaling interfaces in the MG andMGC. It was felt there is a need to reflect an MG’s support for signaling interfaces over interfaceA (i.e., the MG should indicate the signaling interfaces it supports). The B1 interface (to supportH.245 signaling in MG) is included in the Determination of H.GCP. The B2 (H.225) and C(signaling from SCN) interfaces between MG and MGC are for further study. There appears tobe a need for signaling to set up interface D (SCN signaling transport termination).
Any MGC should be able to interoperate with any MG. The combined MG(s) and MGC shalloperate together as a composed gateway.
Discussion of Network Access Server support needs to be added.
Definitions are needed for command and transaction. The concepts of command, transaction, andmessage should be presented before getting into command and transaction details. Otherwise,the discussion of commands, transactions, and messages is in good shape. “Object oriented”language should be replaced.
The definition of the command application programming interface seems to generally be in goodshape, but more work is needed in these areas: error codes, security, MG-MGC control model,naming conventions. There are some good examples (which should be moved to an appendix), butthey are lacking details. Some ideas exist for a transport mechanism, but this topic also needsmore work.
H.246 ANNEX C, CONTROL PROTOCOL, FOR DETERMINATION
TD-21(WP2/16) is draft H.246 Annex C (C. Groves, editor). The purpose of this document is todefine the interworking between Call Signaling Protocols and Media Stream Packetization forpacket based multimedia communications systems and the ISDN User Part functions andprotocol of Signaling System No. 7. It is based on ISUP 1997 and Q.931 1993. This annex ismodeled somewhat after Q.699. A subsequent draft with corrections and modifications waspresented as WD2-11. SG16 Determined H.246 as TD-34(PLEN).
WD2-25 is a liaison to SG11; it describes the work in H.246 Annex C and solicits SG11’s opinion.It was felt that better alignment of H.225 with Q.931 would ease interworking between ISUP andH.323. This work toward alignment might have some problems, so should proceed with caution.This liaison notes that H.246 Annex C should align with the features of H.323/H.225v3. Thereare some concerns about H.320-H.323 interworking using this annex.
H.245V6, FOR DETERMINATION
Contributions Related to New Coder Support
New coder support was discussed during the joint WP1, 2, and 3 meeting, with both supportersand opponents. The GenericCapability and NonStandard (proprietary) constructs werediscussed as possibilities for bringing support for non-standard (non-ITU) coders. A key pointwas made that this is not simply a matter of adding codepoints, but that a total system view
should be considered. Additional contributions are solicited to provide information regardingsystem issues and justifications for supporting non-ITU coders.
The following proposals are to be represented as a GenericCapability. The descriptions of eachshould be considered for an annex to H.245. This Annex should be Determined at this meeting sothat it can be Decided along with H.245v6. The annex will be provided during a rapporteur’smeeting for inclusion in the white document. Packetization provided in the proposals will appearin H.225.0 Annex F.
Changes to H.245v6 are reflected in TD-22(PLEN) and TD-14(PLEN), which were accepted.TD-22(PLEN) addresses the MPEG-4 audio capability description. TD-14(PLEN) addressesthe MPEG-4 system control capability description. (See also the discussion under H.245v6 in theQ11/16 report, above.) H.245v6 was Determined by SG16 as TD-14(PLEN), TD-22(PLEN),TD-24(PLEN), and TD-69(PLEN).
TD-32(GEN) (G. Hellström, acting as editor) is a revision of H.224 (A real time control protocolfor simplex applications using the H.221 LSD/HSD/MLP channels) to include a T.140 code pointin H.224. SG16 Determined the changes to H.224 as identified in TD-11(PLEN).
high end, what SG11’s involvement should be (e.g., specification of MTP layer content). The useof this transport mechanism is interesting and should be studied in more detail for itsapplicability to H.323. The proposal for providing IN services in H.323 systems appearsvaluable and should be pursued further, possibly resulting in another annex to H.246. Futurecontributions should address use in direct endpoint as well as gatekeeper routed models, andshould study the role of the border element. A liaison should be sent to SG11 to engage theirexpertise on interworking between IN and the packet network. A liaison to ETSI TIPHON WG2might also be appropriate.
TOPICS FOR FUTURE WORK IN Q14/16
• New annexes in H.246 for data support (demod-remod for transit networks), including texttelephony (total conversation)
• H.341 support for H.GCP and other features• H.235 support for profiles• H.246 annex for gateway for H.323 over ATM (ATM Forum AF-SAA-0124.000) - need
reference in H.246 to point to ATMF document• H.235v2• Better consideration of firewall and proxy issues• Repairs• Security issues in gateways• Use of IPSEC• Back-end services, accounting, charging• Security profiles proposed by other bodies• Securing IP fax• Security in H.324
Q15/16 WP3, ADVANCED VIDEO CODING
The Rapporteur of Question 15/16 is G. Sullivan (Microsoft, USA). TD-27(WP3/16) is the statusreport and agenda for this meeting. TD-14(WP3/16) and TD-15(WP3/16) are the reports of theinterim meetings in Seoul (Nov. 1998) and in Monterey (Fe.b 1999), respectively. Nearly all ofthe documents from the Q15/16 interim meetings are available on-line at the Q15 externalinformal ftp site <ftp://standard.pictel.com/video-site>. TD-30(WP3/16) is the Q15/16 report ofthis meeting. The Q15/16 e-mail reflector is hosted by PictureTel ([email protected]) which is managed by automatic majordomo software <itu-adv-video-request@ standard.pictel.com>.
The primary Q15/16 goals for this meeting were:1) Coordination with Q11/16 regarding Decision adoption of H.263v2 into H.320 suite (COM-16-
19(WP3/16))• Consideration of plan to issue a revised edition incorporating prior and in-progress
approved amendments and corrigenda (TD-28(GEN))
The video coding area (Q15/16) within WP3/16 currently has two significant on-going activities:H.263++ and H.26L. The H.263++ development effort is toward near-term standardization ofenhancements to the H.263 video codec for real-time telecommunication and related non-conversational services. The H.26L development effort identifies new video coding technologybeyond the capabilities of incremental enhancements to H.263, for longer-term standardization.In addition, Q15/16 supports any needs regarding the existing prior video coding standards(H.261, H.262, and H.263, and presumably H.120, as necessary).
H.262 AMENDMENT 6, NUMBER OF LINES IN ALL PROFILES OF HIGH LEVEL, FOR DETERMINATION
SG16 Determined the text of Recommendation H.262 | ISO/IEC 13818-2 (Information technology- generic coding of moving pictures and associated audio information: video), Amendment 6 assubmitted in TD-19(WP3/16) and forwarded to the Study Group as TD-3(PLEN). Thisamendment provides new upper bounds on the number of vertical lines in all profiles at High andHigh-1440 levels to reflect the agreement of the square pixel common image formal for HDTVsystems in ITU-R BT.709-3 Part II. The value is changed from 1152 to 1088.
RE-ISSUANCE OF H.262 TO INCORPORATE ALL PRIOR AND IN-PROCESS ALTERATIONS
Q15/16 recommends that an integrated version of Recommendation H.262 (Informationtechnology - generic coding of moving pictures and associated audio information: video) be issuedwhich consolidates together all of the previously-approved and in-process changes for editorialimprovement (Integrated edition of ITU-T Recommendation H.222.0 | ISO/IEC 13818-1 and ITU-T Recommendation H.262 | ISO/IEC 13818-2) as proposed in TD-28(GEN). (See the Q12/16report above regarding H.222.)
COORDINATION REGARDING ADOPTION OF A SIGN LANGUAGE AND LIP-READING APPLICATIONPROFILE FOR VIDEO COMMUNICATION
TD-14(GEN) is a liaison statement from SG13, on the ITU IP Project. While the IP-basedapplication is recognized to be a very important target of the video coding standards, the Q15/16experts believe that the existing and future video coding standards developed by Q15/16 aregeneric and already provide significant support for IP environments. Q15/16 will continue toaddress this important application in its future work, as well as other applications. TD-15(GEN) is another liaison from SG13 on IETF working groups. Q15/16 work is potentiallyrelated to the activity of the AVT WG, since no activity on video codec development is found inIETF WGs.
TECHNICAL PROPOSALS FOR H.263++ AND H.26L PROJECTS: CONTENT-BASED COEFFICIENT MAPPING
The benefit was shown relative to an encoder which made no distinction between foreground andbackground regions.
Some comments noted that the benefit shown using this method should be compared against thebenefit that can be obtained using a well-designed encoder-only region-of-interest enhancementmethod requiring no syntax modification. For example, the reference encoder could usemanipulation of DQUANT step-size changes as defined in H.263 Annex T (along with encodingotherwise according to the test model also using Annexes D, F, I, and J). It was thereforesuggested that the proponent bring such a demonstration in the future to Q15/16.
It was agreed that the technology areas of work designated for the H.263++ and H.26L projectsbe modified to add mention of an investigation of this technology proposal.
PLANNING AND WORK ON H.263++
The H.263++ Workplan follows:
Mtg Dates Type MilestoneQ15-H Aug ‘99 Experts Last Formal Draft AdoptionsSG16-5 Sep ‘99 SGQ15-I Nov ‘99 Experts Final Draft for DeterminationSG16-6 Feb ‘00 SG DeterminationQ15-J May ‘00 Experts Bug-checkingQ15-K Aug ‘00 Experts Final Draft for Decision
Jan ‘01 SG Decision
The group discussed the current status of work on H.263++. The five previous and one new keytechnical areas that appear to be promising for further investigation:
1. Enhanced reference picture selection (adopted as a draft for future Determination as Annex U)2. Error resilient data partitioning (adopted as a draft for future Determination as Annex V)3. Affine motion compensation (in collaborative proposal development)4. IDCT mismatch reduction (one proposal previously received)5. Error concealment (normative or informative, no formal proposals yet received)6. Content-based coefficient mapping (proposal received at this SG16 meeting)
PLANNING AND WORK ON H.26L
The current workplan of the H.26L project is provided in TD-48(PLEN) Annex Q15.A, and isshown below:
Mtg Dates Type MilestoneQ15-H Aug 99 Experts First Formal Draft AdoptionsSG16-5 Sep 99 SGQ15-I Nov 99 ExpertsSG16-6 Feb 00 SGQ15-J May 00 ExpertsQ15-K Aug 00 Experts Final Major Feature Adoptions
The H.26L project appears to be on track, and will continue to be led by Associate Rapporteur K.Hibi (CIAJ). A significant milestone for this project was reached at the Nov. 1998 Rapporteur’sgroup meeting, at which the first full algorithm technical proposals were evaluated for H.26L.
Significant progress was made, in particular, in the coding efficiency area, at the two interimRapporteurs group meetings. Q15/16 decided to move forward in expectation of achieving thegoals of H.26L with further improvement by collaborative effort, although no particular proposalfully meets all the requirements for H.26L at this time.
According to the discussion on the similarities in technical natures of H.26L proposals, H.26LKey Technical Areas of interest were identified:
Inter frame prediction coding(1) Variable-size block-based segmentation
- Quad-tree like decomposition of frame- Small block size to 8x8, 4x4
(2) Long-term memory- Increase candidates of reference materials for prediction- Combination with other prediction scheme (e.g., affine warping)
(3) Affine motion model- Adoption of six parameter affine motion model- Coding method and syntax of affine motion parameters- Searching of affine motion parameters
Inter frame residual coding (also applicable to Intra texture coding)(4) 16-sampled waveform coding (4x4)
- Coding with smaller block size than 8x8 DCT(5) VQ, EZW with DCT, multiple waveform coding
- Adoption of (variable-dimension) VQ scheme- Embedded EZW structured coding- Selection from multiple coding modes- Zero-tree structured coding of subset of coefficients
Intra frame coding(6) Directional (pixel-prediction) Intra coding
- Improvement of prediction in Intra coding- Consideration of activity direction of picture
The current technical work of H.26L seems to mainly focus on coding efficiency improvement; allfunctionalities listed in the H.26L requirement document should be finally supported. Q15/16agreed upon the following functionality areas for the H.26L development process:
(a) High compression performance- Capable of 50% or greater bit rate savings relative to ‘98 H.263v2 (DFIJT) at all bit rates
(b) Simplification “back to basics” approach- Adoption of a generally simple, straightforward design using well-known building-blocks- For example, use of one VLC for all parameters to be coded
(c) Flexible application to delay constraints appropriate to a variety of services- Low delay (e.g., no B pictures) for real-time conversational services- Moderate delay usage appropriate for sever-based streaming application
(d) Error resilience- Packet loss resilience- Mobile channel corruption resilience
(e) Complexity scalability in encoder and decoder- Asymmetry of encoder and decoder processing complexity- Scalability between amount of encoder processing and achievable quality
(f) Full specification of decoding (no mismatch)- Resolve mismatch problem (e.g., integer transform, VQ, et al)
(g) High quality application- Performance improvement in higher bitrate- Applicability to entertainment-quality applications
(h) Network friendliness- Ease of packetization- Information priority control
As a next step, since H.26L should move into a collaboration phase as soon as possible,proponents of H.26L technical content are asked to seek common ground. For maximizing aneffectiveness of collaborative effort, the test model for H.26L and relevant core experimentsshould be defined in later stage.
LIAISON STATEMENTS
TD-06(WP3/16) is a liaison from ITU-T TG 8/1 regarding Multimedia coding for IMT-2000. Itrequests that Q15/16 keep them informed on work related to H.263++ and H.26L. The reply, inTD-49(PLEN), discusses H.263 in detail.
TD-09(WP3/16), a liaison from ITU-T SG12 regarding A/V Quality Assessment, notes thatQ10/12 and Q11/12 are planning to address perceptual video quality assessment methods forvideo with transmission errors, and requests any related information from Q15/16. TD-49(PLEN) contains the reply.
A liaison to ISO/IEC JTC1 SC29 WG11 (in TD-49(PLEN)) notes the work in Q15/16 andrequests collaboration with WG11 in video coding development.
TD-38(GEN), an output liaison statement to ISO/IEC JTC1 SC29 WG11, was generated jointlywith Q12/16 regarding publication of an integrated version of Recommendation H.262.
Q16/16 AND Q17/16, MULTIMEDIA HARMONIZATION AND COORDINATION
The Question 16-17/16 Rapporteur is M. Matsumoto (Japan), assisted by T. Taylor (Nortel,Canada). The agenda is in TD-30(GEN). The meeting report is TD-70(PLEN). Some progresswas made on the GII Projects. Projects F.3 (Information Appliances) and M.4 (MultimediaMiddleware) have been closed for lack of interest. Work on Projects F.4 (End to EndInteroperability) and M.3 (E-Commerce) continues and will be progressed at an interim meetingAugust 25-27, 1999 in Geneva. A report of the joint meeting of Q1 and Q16 on Project M.3 is inAnnex 3 of TD-59(PLEN), the WP2 meeting report. (See also the Q1/16 and Q2/16 reports,above.) No substantive activity occurred. A new project, Mediacom 2004, was started tointroduce the role and responsibility of each SG in the multimedia environment. The first draft ofthis work is in Annex 1 of TD-70(PLEN).
LIAISONS
TD-2(GEN) and TD-3(GEN) from JQG1/11 (Joint Question Group created by SG11 for IMT-2000 layer 2 coordination) discusses IMT-2000 multimedia requirements and Layer 2 radiointerface work. They are in response to the SG16 liaison and request additional information onacceptable error rates, H.323 and H.324 requirements. Draft Recommendation Q.1732.1,Functional specifications and requirements for IMT-2000 layer 2 radio interface, is attached toTD-3(GEN). TD-67(WP2/16) is the reply by the Rapporteurs for Questions 11/16 and 13/16,noting new work in SG16.
TD-10(GEN) is progress on work related to middleware from SG10. SG10 is asking forcomments to the report if necessary. On this issue, it was reported that the work of GII M.4 onMiddleware for Multimedia was closed recently. No action was needed. (See also Q2/16, above.)
TD-13(GEN) (SG13) is a copy of the GII Project plan prepared by SG13 at its meeting inFebruary. As a result of the establishment of a new “ITU-T IP Project,” the GII Projects nolonger include I.1 and I.2. These have been incorporated into the new IP Project. However,SG13 will continue its own studies on GII and will continue to monitor the work on the GIIProjects in the other Study Groups. In this regard, SG13 is planning to hold a short meeting toreview the GII work in association with an “IP Experts Meeting” in September.
Q16-17/16 felt that the current activities in SG16 should be input to the planned meeting. Thedeadline for the Input is before the end of July. Q16-17/16 thought that the GII Project, ProjectF.3 on Information Appliance and Project M.4 on Middleware for Multimedia had finished.However it was decided that Projects F.4 on end-to-end interoperability and M.3 on electriccommerce will continue. The F.4 Project draft will be updated, and will be submitted to the next
GII meeting. Annex 2 (to TD-70(PLEN)) is proposed information from the Rapporteur to thisGII meeting in September. (See also Q2/16, above.)
TD-14(GEN) (SG13) introduces the newly established IP Project. In particular, in order toprogress rapidly, the project will be discussed at the IP Experts meeting in September; TD-14(GEN) is also an invitation to join the meeting. (See also Q15/16, above.)
TD-15(GEN) (SG13) lists the relationship between ITU-T Study Groups and IETF WorkingGroups. The information was preliminary and comments on the document were requested.
TD-16(GEN) (SG13) is the multimedia coordination “Status of Activities.” The currentrecommendation status was requested. TD-72(PLEN) is the return liaison.
MEDIACOM 2004
Q16-17/16 felt that it was time to develop Multimedia Project, which will introduce the role andresponsibility of each Study Group in the multimedia environment. It was confirmed that thework on the update of Rec. H.200 should be the umbrella of the MEDIACOM 2004 Project.
The title for the project as “MEDIACOM 2004” was proposed and agreed in the meeting. TheRapporteur prepared the first draft Multimedia Project, version 0.1. An interim meeting on thisissue is planned for August 25-27 in Geneva. The first draft is in Annex 1 of TD-70(PLEN).
Q19/16 WP3, EXTENSION TO EXISTING ITU-T SPEECH CODING STANDARDS AT BIT RATESBELOW 16 KBIT/S
The Q19/16 Rapporteur is S. Hayashi (NTT, Japan). The agenda is TD-1(WP3/16). Themeeting report is TD-35(WP3/16).
VBD CAPABILITY FOR THE 40-KBIT/S EXTENSION OF G.728 ANNEX J, FOR DETERMINATION
Q19/16 is currently testing the performance of a 40 kbit/s extension to G.728. The extension isaimed at DCME applications mainly for data transmission. The test methodology for voice-banddata (VBD) capability assessment of a 40 kbit/s extension to G.728 was finalized in Feb. 1998.COMSAT performed VBD tests on the candidate algorithm submitted by MOC Israel using thistest methodology.
After revision of the test results, Q19/16 was satisfied with the performance and decided that thecandidate should be Determined as the draft Annex J (Variable bit-rate operation of LD-CELPmainly for VBD applications in DCME) to G.728 with the following conditions:
• The text of the draft Annex J should be corrected by the editing group, taking into account theErrata presented by Mitsubishi in the September SG16 meeting in 1998;
• Test reports on the DTMF capability should be presented at the next Rapporteurs meeting,although performance with DTMF signals is an objective. The test will be performed by theproponent.
• Test vectors (used to certify an implementation) should be made available before Decision(scheduled for September 1999)
• In case any algorithmic modification is made after the Determination, data performance testsshould be performed to ensure that either bit exactness is achieved, or that no degradation innon-voice performance is observed.
G.728 Annex J was Determined by SG16 as TD-67(PLEN).
The Rapporteur reported receiving a number of written communications indicating possibleproblems in the text of Annex G (16 kbit/s fixed point) to G.728. Although the current technicalcontent of the Annex is believed to be correct, there may still be a few editorial errors in G.728Annex G. The Rapporteur will prepare a list of the possible errors and make it available to theexperts via correspondence. A Corrigendum will be proposed at the next SG16 meeting ifdeemed necessary.
PACKETIZATION FOR G.729 ANNEXES C, D AND E IN H.225.0
The recently approved Annexes D (6.4 kbit/s CS-ACELP speech coding algorithm) and E (11.8kbit/s CS-ACELP speech coding algorithm) to Rec. G.729 provide variable bit rate operationcapability to G.729 (Coding of speech at 8 kbit/s using conjugate-structure algebraic-code-excitedlinear-prediction, CS-ACELP) and G.729 Annex A (Reduced complexity 8 kbit/s CS-ACELPspeech codec) codecs. Annex C specifies a floating point version of these two algorithms. TD-28(WP3/16) (Q19/16 Rapporteur) defines packetization for each of these codec extensions. Inparticular, these definitions are consistent with the packetization adopted in I.TRUNK (I.362.2,AAL Type 2 service specific convergence sublayer for trunking). This material was provided toQ13/16 for incorporation in H.225.0 version 3, Section F.3.
recognized that quality improvement is possible with this algorithm and encouraged independentquality verification tests of the current algorithm, or alternative methods or variations.Contributions on how to extend the algorithm for ADPCM coding such as G.726 are alsoencouraged. The initial target of this work will be to produce an Appendix to G.711, possiblyextending support for other waveform based coding. The target date to complete the technicalwork is Sept. 1999.
LIAISONS
TD-8(WP3/16) is a liaison from SG12. Q14/12 notes Q19/16’s request for methodologies requiredto test VAD (voice activity detection), CNI (comfort noise insertion), DTX (discontinuoustransmission) and similar algorithms. Information may appear at the next SG12 meeting.
TD-49(PLEN) includes a liaison to ITU-R TG8/1, regarding the formal approval of Annex I toG.728 (Frame Erasure Concealment for LD-CELP at 16, 12.8 and 9.6 kbit/s), and of aCorrigendum for Annex H to G.728. It also reports the progress of the work on frame erasureconcealment techniques for waveform-based speech coding such as G.711.
TD-4(WP3/16) is a liaison from Q6/15 noting that G.767 (Digital circuit multiplication equipmentusing 16 kbit/s LD-CELP, digital speech interpolation and facsimile demodulation/remodulation)was Decided, and that G.767 expects to use the VBD-optimized coding algorithm from G.728Annex J. The reply to ITU-T SG15 is in TD-49(PLEN); it announces that a Corrigendum toAnnex H to G.728 was formally approved, and that Annex J to G.728 was Determined by SG16.
FUTURE WORK
Q19/16 will hold a Rapporteurs meeting September 27-29 1999 in Geneva, subject to thesubmission of contributions. The issues to be addressed are:
• Contributions addressing the Decision of Annex J to G.728,• Extension of Annex C to G.729 to include Annexes B, D, and E (floating point),• Approval of the frame erasure concealment algorithm as an Appendix to G.711,• Test vectors for Annex C to G.729,• Maintenance of existing speech coding recommendations.
Q20/16 WP3, AUDIO AND WIDEBAND CODING IN PUBLIC TELECOMMUNICATIONNETWORKS
The Q20/16 Rapporteur is R. D. De Iacovo (CSELT/Italy). TD-11(WP3/16) is the meetingagenda; TD-12(WP3/16) is the Q20/16 progress report. TD-38(WP3/16) is the meeting report.
The Q20/16 objectives were to evaluate the results of the selection test for wideband coding at 24and 32 kbit/s and define the Terms of Reference for wideband coding at bit-rates around 16kbit/s.
PRESENTATION OF SELECTION TEST RESULTS AT 24 AND 32 KBIT/S
The six listening laboratories participating in the selection listening tests presented theirrespective results:
All of them were judged compliant in meeting their deliverables according to the contents of thesigned Memorandum of Understanding. As a consequence, the listening laboratories areexpected to send a bill to ITU-T TSB for payment.
The global analysis of the wideband codec selection tests (24/32 kbit/s) was presented by theRapporteur.
Annex A to TD-38(WP3/16) presents the results for each laboratory and global (normalized byMOS) results. On the basis of the measured performance of the tested algorithms, the followingmain conclusion were drawn:
1. EXP1: requirements were not met by both candidates in connections with 3% random frameerasure conditions. Candidate A met requirements and objectives in clean speech conditions(1, 2 and 3 tandems). Candidate B met requirements in clean speech conditions at 24 kbit/s (1,2 and 3 tandems) and the requirement at 32 kbit/s in 1 tandem.
2. EXP2: requirements and objectives were met by candidate A except in random frame erasureconditions (1%, 3%, 5%). Requirements and objectives were met by candidate B.
3. EXP3: requirements (except one case) and objectives were met by candidate A. Requirementsand objectives (except two objectives) were met by candidate B.
DISCUSSION OF TEST RESULTS
TD-13(WP3/16) contains the version 2.0 (December 1998) Selection Test Plan for the ITU-TWideband (7 kHz) Speech Coding Algorithm at 24 and 32 kbit/s.
TD-20(WP3/16) (Q20/16 Rapporteur with SQEG/12 chair) is a global analysis of the widebandcodec selection test.
Starting from the subjective test results obtained in the selection phase, Q20/16 discussed how toprogress in the activity of wideband coding at 24 and 32 kbit/s.
Requirements on QualityIn 3% random frame erasure condition, with speech as input signal, the requirements were notmet by both candidates. One party wanted to stick to the requirements and objectives as theyare in the actual Terms of Reference for wideband coding. The majority, however, expressed thedesire to select one of the two candidate algorithms on the basis of their performance results andcomplexity. To substantiate a decision, the group started considering several aspects, as follows.
Quality in frame erasure conditionsAs regards the robustness of the candidate algorithms in error prone environments (especially inconditions with frame erasure conditions), both proponents declared that improvements arepossible in their respective algorithms; a common feeling of Q20/16 was that a viable approach isto defer to a subsequent study the inclusion of those improvements in an Annex, if aRecommendation is Determined at this meeting.
ApplicationsFollowing the reasoning above, it was attempted to define the applications that can beaccommodated by each candidate algorithm, on the basis of their performance andcharacteristics. The definition of the area of applicability was considered important, whatevercandidate will be chosen.
As preliminary indication, the first four applications of the Terms of Reference were listed:
1. ISDN videotelephony on Basic Rate Access (Note 1)2. ISDN video-conferencing on Basic Rate Access (Note 1)3. ISDN wideband telephony (e.g., for multichannel applications) (Note 2)4. Wideband transmission over Internet (Note 3)
Note 1: One of the envisaged scenario is hands-free communication in presence of backgroundnoise, even if a wider range of environments is possible.
Note 2: Both hands-free and handset communications are envisaged.Note 3: The range of applicability is restricted to the applications where error protection is
accomplished using appropriate protocols.
At the same time, the issue of complexity was raised; Q20/16 considered this to be of primeimportance.
ComplexityThe computational complexity and memory requirements of the NTT candidate algorithm (A) arereported in Table 4. A bit-exact, fixed-point descriptive approach was followed using the G.729basic operations.
The implementation details of the PictureTel candidate algorithm (B) are reported in Table 5 forboth fixed and floating point implementations.
DecisionThe following four possible scenarios were discussed:1. Select no candidate, since not all requirements are met.2. Select the codec with lower complexity (which has some problems in clean speech conditions)
for hands-free operation.3. Select the codec which has better clean speech performance but higher complexity.4. Consider both codecs for different sets of applications as appropriate.
While scenarios 1 and 4 had no or little support, the majority favored the scenario 2. On thatbasis, Q20/16 agreed to pursue scenario 2 and select candidate B for Determination at thepresent SG16 meeting. It was felt that the coder met the need of the hands-free applicationsoutlined in section 0.
As confirmed by a letter signed by AT&T (the third party laboratory in the blinding procedure),Candidate B is the PictureTel candidate algorithm.
TD-21(PLEN) is G.722.1 (ex-G.WB1) proposed for Determination: 7 kHz Audio Coding at 24and 32 kbit/s for hands free operation in systems with low frame loss. It was Determined bySG16, with changes in TD-51(PLEN).
Other Issues: C-code and Test VectorsSome organizations requested to have, at the Decision meeting, the C-code based on the library ofbasic operations that is under definition in Q22/16 (a superset of the G.729 basic operations).
PictureTel declared that work will be started in that direction and that collaboration withorganizations that have experience in the field would be helpful.
PictureTel also asked for collaboration in the preparation of an appropriate set of test vectors forthe wideband algorithm.
The question was raised: Should the C-code contained in a Recommendation for speech/audiocoding be used just as a reference, and should different implementations be allowed, or should itbe mandatory? It was agreed that a global answer, valid for all the Recommendations understudy in WP3, should be given.
The provisional contact person in case problems are revealed by third parties in the C sourcecode is Antony Crossman, PictureTel, Phone : +1 978 623 4557, Fax : +1 978 749 2804, E-mail:[email protected]
Other Issues: Characterization Test PlanIt was agreed to ask SG12 for guidance in preparation of a characterization test plan for thewideband algorithm at 24 and 32 kbit/s. It must take into consideration the scope of theRecommendation and test results already obtained in the previous selection test phase. Fundinghas not yet been identified for the Characterization Tests.
Other Issues: Annex Robust Under Frame Erasure ConditionsContributions are solicited for the next Rapporteur’s meeting from the interested organizations onthe possible techniques to be used to increase robustness in frame erasure conditions. Anappropriate way forward will be planned on the basis of those contributions.
TERMS OF REFERENCE FOR WIDEBAND CODING AT AROUND 16 KBIT/S
The following general guidelines were discussed and considered relevant for this widebandactivity:• Input and output audio signals should have a bandwidth of 7 kHz at a sampling rate of 16
kHz.• Primary signals of interest are clean speech and speech in background noise. Music
performance requirements set at higher bit-rates (24 kbit/s).• High speech quality with the objective of equivalence to G.722 at 56/64 kbit/sec.• 16 kbit/s is the main bit-rate. The candidate is required to be able to scale in bit rate to lower
bit-rates (less then 16 kbit/s) and up to 24 kbit/s with no fundamental changes in either thetechnology or the algorithm used.
• Robustness to frame erasures and random bit errors.• Low algorithmic delay (frame size of 20 ms or integer sub-multiples)
Based on the above, the Terms of Reference for a new wideband (7 kHz) coding activity at around16 kbit/s, with focus on speech, were prepared as contained in Annex 20.B to TD-48(PLEN).
Q20/16 is considering adopting the fixed-point description based on the library of basicoperations, under study in Q22/16, and some inputs on this Q22/16 action point are expectedfrom organizations involved in the wideband activity (see the Q22/16 report, below).
The discussion was held on the time schedule and T0 time (starting point in time of thestandardization process). It was generally agreed that if frozen Terms of Reference and acorresponding Qualification test plan are ready at the next Rapporteur’s meeting (September1999), the possibility of having T0 time at the next SG16 meeting (February 2000) will be
considered. Moreover, Q20/16 briefly addressed how to proceed in testing the candidatealgorithms. Some views were expressed in favor of a centralized host lab approach (sameapproach followed in the 4 kbit/s effort) even if a firm decision was not reached. The matter willbe addressed at the next Rapporteur’s meeting.
LIAISON STATEMENTS
TD-03(WP3/16) is a liaison from SG15. Q6/15 (CME) noticed that there is an objective forvariable bit-rate compatibility in the Q20/16’s terms of reference for Speech Coding Algorithm at24, 32 kbit/s referring to the capability of easy adaptation for packet and DCME applications.Q6/15 does not currently plan to use a 24, 32 kbit/s variable bit rate wideband speech codec inCME applications, such as DCMEs or ATM Voice CLAD (Cell Assembly/Disassembly).
TD-5(WP3/16) is a liaison from ITU-R Task Group 8/1, noting applications they foresee for theQ20/16 wideband coder for videotelephony and audio conferencing in IMT-2000. Another replyliaison was drafted to inform ITU-R TG8/1 of continuing activities on the wideband codingactivities (TD-40(WP3/16)).
TD-7(WP3/16) is a liaison from ISO/IEC JTC1/SC29/WG11 on the MPEG-4 audio verificationtest results: audio on the Internet. Attached are the details of MPEG’s multi-language MOSverification tests referenced to existing codecs:• Audio tools in MPEG-4 on speech applications (16 to 56 kbit/s)• Digital audio broadcasting on AM modulated bands (16 to 24 kbit/s)• Internet audio applications (6 to 56 kbit/s)
TD-8(WP3/16), a liaison from SG12, notes that the final test plans and laboratory allocationswith be provided to Q20/16 after the next SG12 meeting.
TD-39(WP3/16), a liaison to SQEG/SG12, informs them about the new Determined ITU-TRecommendation on wideband coding at 24, 32 kbit/s, asks support in developing an appropriatecharacterization test plan, and asks which listening laboratories are available for testing. It alsorequests them consider the preparation of a qualification test plan for wideband coding around 16kbit/s, based on the ToR as defined in the present meeting. The aim is that if minor refinementsare made to the ToR during the September 1999 meeting, they should be easily incorporated inthe final version of the Qualification test plan.
FUTURE WORK
The tentative schedule for Decision of the 24, 32 kbit/s algorithm is planned at the September1999 meeting in Geneva. A Q20/16 Rapporteur’s meeting is also planned during September 27-29, 1999.
Q21/16 WP3, ENCODING OF SPEECH SIGNALS AT BIT RATES AROUND 4-KBIT/S
The Q21/16 Rapporteur is P. Barrett (BT, UK). TD-23(WP3/16) is the report of the previousQ21/16 meeting (September 1998). TD-25(WP3/16) is the agenda and objectives for thismeeting. TD-34(WP3/16) is the report from this meeting.
The objective of this meeting was to prepare for the Coordinated Qualification Phase of the ITU-T4-kbit/s speech coding work (G.4k). Declarations of intent were submitted for sixteen candidatespeech coding algorithms. The meeting approved the schedule for the qualification phase andaddressed outstanding issue. The results of the qualification experiments will be reviewed at aRapporteur’s meeting September 27-29, 1999.
Fifteen candidate proponents identified their intent to submit candidate algorithms to the ITU-T4-kbit/s qualification phase. Ascend Communications declared their intention to submit (and fundthe testing for) two codecs, making a total of sixteen candidate algorithms. All fifteen candidateproponents confirmed that they would abide by item 2.2 of the ITU patent policy with respect totheir ITU-T 4-kbit/s candidate submission. The candidate proponents (and documents of intentsubmitted to this meeting) are listed in Table 6 (see also Annex Q21.A of TD-48(PLEN)).
* Ascend Communications Inc. declared the intent to submit two candidate algorithms.
Table 6. List of 4-kbit/s speech codec proponents.
QUALIFICATION PHASE: LABORATORY BIDS
Q21/16 reviewed three bids for the laboratory functions of the qualification phase (TD-16(WP3/16)). ARCON and COMSAT submitted bids for both the host laboratory and listeninglaboratory functions; DYNASTAT submitted a bid for the listening laboratory function only. TheRapporteur confirmed that these bids had been received by the April 19, 1999 deadlineannounced on the WP3 and SQEG/22 e-mail reflectors.
In light of the large number of candidate algorithms and the short period available to perform thequalification phase, the three laboratories agreed to share the workload: ARCON stated thatthey could process the speech material for both qualification experiments at a cost of US$4,000per candidate; DYNASTAT stated that they could perform Experiment 1 (ACR test) at a cost ofUS$7,500 per candidate; COMSAT stated that they could cross-check the processing of thespeech material and perform Experiment 2 (CCR test) at a cost of US$10,000 per candidate.Q21/16 agreed upon this subdivision of the work for the costs stated.
DYNASTAT stated that they would also provide previously unused North American Englishspeech material for both qualification experiments; ARCON stated that they would providesuitable background noise material for Experiment 2 and process the demonstration material.
QUALIFICATION PHASE: MOU MATTERS
The Rapporteur proposed the process contained in TD-17(WP3/16) as the basis for themanagement of the legal aspects of the 4-kbit/s qualification phase. This process is based on theprocedure used for the ITU-T Q20/16 wideband selection phases, whereby the ITU acts as acentral agent between the candidate proponents and the laboratories. The ITU charges a 5%administration fee in addition to the laboratory costs. Q21/16 agreed that this procedure wouldbe adopted for the 4-kbit/s qualification phase. The total cost of the qualification phase willtherefore be US$22,575 per candidate algorithm.
The fifteen candidate proponents and the three laboratories stated that they agreed to versions1.1 of the MoU and NDA distributed in TD-17(WP3/16). The necessary editorial changes will bemade to accommodate the cross-checking function and the use of two listening laboratories.
QUALIFICATION PHASE ISSUES
ARCON and COMSAT confirmed that they could support a number of processing platforms, andit was agreed that candidate proponents could submit their executables for the platform of theirchoice. The Rapporteur undertook to compile a list of platform requirements.
Q21/16 agreed that demonstration material would be provided for each candidate algorithmpresented for further consideration in September 1999. The demonstration material will besupplied using a blind mapping (different to that used between the host and listeninglaboratories). The mapping of the demonstration material will not be disclosed. DYNASTATagreed to provide additional sentences from the speech corpus used for the qualificationexperiments for the demonstration material. It was agreed that the background noise materialused in Experiment 2 would be used for the demonstration material.
The processed speech material will be provided to the listening laboratories for each experimentusing a blind candidate mapping. Candidate proponents will only see the qualification testresults for their own codec algorithms(s) prior to the September Q21/16 meeting. Proponents willbe given the opportunity to withdraw their candidate(s) prior to this meeting, under whichcircumstances the qualification test results and the demonstration material for the candidate inquestion will be kept in confidence by the listening and host laboratories. The qualificationresults of the remaining candidate algorithms will be presented to the Q21/16 meeting inSeptember 1999 on the basis of one document per candidate algorithm. The name of thecandidate proponent will be clearly stated in each set of qualification results submitted to Q21/16.
REVIEW OF 4-KBIT/S QUALIFICATION TEST PLAN
ARCON and COMSAT agreed to an annex to the Qualification Test Plan describing the cross-checking procedure. The annex, TD-48(PLEN) Annex Q21.E, was originally submitted as TD-18(WP3/16). A further annex (TD-48(PLEN) Annex Q21.F) will be added to the test planspecifying the format of the executable code to be delivered by candidate proponents to the hostlaboratory. The G.711 processing stages will comprise A-law codecs preceded by 16 to 13 bitrounding. The listening laboratories agreed that no fewer than 10 male or 10 female subjects willbe used in any experiment.
After a discussion on the relative merits of handset or headset testing, it was agreed to adopt theuse of headsets as specified in version 2.3 of the test plan.
REVIEW OF SCHEDULE
Q21/16 agreed upon the ITU-T 4-kbit/s Qualification Phase Schedule in TD-48(PLEN) AnnexQ21.B. This schedule plans to complete the qualification testing by September, 1999. Q21/16also modified the main 4-kbit/s Schedule (TD-48(PLEN) Q21.D) for the ITU-T 4-kbit/sstandardization program. The revisions were the use of wMOPS rather than a DSP simulationfor the selection phase complexity evaluation, and a clarification of the qualification deliverableswith respect to noise suppression technology. The overall schedule proposed for the developmentof a 4-kbit/s speech-coding algorithm is shown in Table 7.
Start time Item Estimatedcalendar time
T0 Submission of qualification deliverables 9/99 during SG12T0 + 4 months Commence selection testingT0 + 9 months Selection of one candidate for further consideration (the selected
candidate not necessarily identical to one of the source candidatesdue to possible compromise mixture);
mid 2000, duringSG12
T0 + 12 months Determination of Recommendation and C-source code 9/00 SG16 WP3T0 + 13 months Final text of Recommendation and C-source code available for TSBT0 + 18 months Approval (Decision) of Recommendation. Q1, 2001 SG16
Table 7. Development Schedule for 4 kbit/s Speech Coding Algorithm.
REVIEW OF TERMS OF REFERENCE (TOR)
Noise SuppressionQ21/16 discussed a request for clarification on the use of noise suppression in candidate codecalgorithms, since this is not addressed in the ToR (TD-48(PLEN) Annex Q21.C). A number ofdelegates felt that it was difficult to specify what does, and does not, constitute a noisesuppression algorithm, because some techniques are essentially embedded in the codec
architecture. Other delegates felt that separate pre-processing stages should be excluded.Concerns were also expressed over the use of the CCR (Comparison Category Rating) method ofspeech quality assessment for algorithms utilizing noise suppression techniques.
Given the July 5, 1999, deadline for the delivery of qualification executables, Q21/16 agreed notto add any restrictions in the ToR with respect to noise suppression. A liaison will be sent toSQEG asking them to consider the possibility of noise suppression algorithms existing incandidate algorithms when preparing the ITU-T 4-kbit/s Selection Test Plan.
ComplexityThere was a request to clarify the complexity requirement in the ToR. The Rapporteur drewQ21/16’s attention to fact that the objective for complexity is “as low as possible” and thatcomplexity had been an important factor in the selection of the wideband codec by Q20/16 at thisSG16 meeting.
The Rapporteur stated that Q21/16 had clear goals for the first part of the next Study Period,and reminded the meeting of the work items on voice activity detection and higher and lower bit-rate extensions in the ToR. The text of Q21/16 will be distributed on the WP3/16 reflector forcomment prior to the next SG16 meeting.
LIAISON STATEMENTS
TD-8(WP3/16) is a liaison from SG12. It notes that a revised section on listening methods foruse in the 4 kbit/s qualification was prepared and included in the Qualification Test Plan Rev2.30. Subjective testing labs were informed of the Q21/16 desire to have a single lab conductqualification tests and have been invited to contact the Q21/16 Rapporteur.
TD-10(WP3/16) is a liaison from ITU-R TG 8/1, noting the upcoming revision of Rec. ITU-RM.1079, Speech and voiceband data performance requirements for IMT-2000. It requestsinformation concerning applicable existing or forthcoming recommendations.
A liaison statement was drafted to inform SQEG of the progress in Q21/16, and to inform SQEGthat the selection phase may contain algorithms that utilize noise suppression technology. Aliaison was also drafted to ITU-R TG 8/1 to inform them of the number of candidates algorithmsto be evaluated in the qualification phase. Both are contained in TD-37(WP3/16).
Q22/16 WP3, SOFTWARE AND HARDWARE TOOLS FOR STANDARDIZATION OF SPEECH ANDAUDIO CODING ALGORITHMS
The Q22/16 Rapporteur is S. F. Campos-Neto, COMSAT). TD-22(WP3/16) provides a report ofthe interim activities.
Currently Q22/16 is dealing with the maintenance and future enhancements of the ITU-TSoftware Tool Library, release 1996 (STL96). Q22/16 reviewed and approved the maintenancework performed by correspondence; it also agreed to add existing basic operators to the ITU-Tsoftware tool library (STL), and to discuss by correspondence the definition of new operators aswell as a revision of the weights currently associated with the existing basic operators. Littleprogress was made in this period, although some minor bugs were corrected and identified.
Q22/16 also agreed to work towards Determination of a new release of the ITU-T STL at the nextSG16 meeting, code-named STL2000.
SOFTWARE TOOLS: MAINTENANCE AND REVISIONS
A problem was identified at the last meeting: files in some instances were processed for lesssamples than the total specified by the user when the file size was not a multiple of the block size.This problem has been fixed in g726demo.c, filter-d.c, g722demo.c (originally reported forsv56demo.c and actlevel.c). Additionally, the header file ugstdemo.h preamble was changed todefine MS-DOS for the gcc compiler under Win95/CYGWIN32 as well as for the MS Visual Ccompiler.
FIR. The receive side of the modified IRS filter (provided by Voxware) has not yet beenimplemented in the STL. An optional sample delay was implemented in the demo program filter.cwhen the asynchronization option is selected. This was done in response to the fact that filteringby itself by the wideband asynchronization filter in the STL introduces only a very small amountof asynchronization, in the order of a few samples. For the wideband exercise, a value of 160 waschosen and set as default. This change was incorporated in a “sister” version of filter.c, calledfilter-d.c in order to avoid confusion in the wideband selection exercise as to which version of thetool should be used. The filter-d.c was checked in HPUX, DJGPP, and TCC. Two new processedfiles were produced, tst-asyd.flt and tst-asys.flt. Appropriate portability tests were added to themakefiles.
Q22/16 agreed to replace eSTL9801’s filter.c with the new version. Q22/16 also agreed with theprinciple to include the ETSI MSIN filter characteristic into the FIR module.
G.726. DSPC provided a fix for g726.c that is supposed to fix the long-standing problem with onetest vector for the 40 kbit/s rate. Verification of the impact of the change remains to be checked.
EID. A bug was fixed in gen-patt.c when the option to skip some bits or frames was selected forbit error/frame erasure:• It was saving 0x007F to file when the skip option was enabled for (B)FER mode when it should
be 0x6B21• It was saving the wrong number of bits or frame flags• It was computing the BER/(B)FER based on the ratio of disturbed bits over processed bits.
This is OK for skip==0, but for skip>0, the proper ratio is disturbed/generated (generated isprocessed plus skipped).
The problem was corrected and tested under HPUX. The change needs to be verified in otherplatforms, but should not present any problems.
Still in the EID module, Q22/16 removed cosmetic compilation warning in file save_EID_to_file(),which affects compilation of files eiddemo.c and eid_io.c.
Unsupported Tools. In support for the wideband selection tests cross-check activity, a portable32-bit CRC calculation tool was made available. The reported number of comparisons performedin compfile.c, which was incorrectly reported when file sizes were not a multiple of block size, hasbeen corrected. Information regarding usage of the delay option was improved. In oper.c,modified formatting of usage information was modified, and the confusing message “trimming bythe size of ... file” when files are of the same size was removed.
During discussion, it was clarified that the main purpose of the basic operators is to emulateinstructions available in current digital signal processors; the basic operator definition willbenefit future standardization efforts.
Q22/16 agreed to incorporate the updated G.729 operators into the STL, together with the threeG.723.1 basic operators not present in G.729. More discussion is necessary on the definition ofnew basic operators.
Q23/16 WP1, PCM MODEMS
The Rapporteur for 23/16 is L Brown (Motorola, USA). The agenda for the meeting is TD-21(WP1/16). TD-22(WP1/16) is the report of the San Diego, California, Q23/16 Rapporteurmeeting in December, 1998.
LIAISONS
TD-1(WP1/16), a liaison from SG8 concerns connection problems with some V.34 half-duplexmodems; Q23/16 agreed that Q4/16 should address the issue. (See the Q4/16 report, above.)
TD-4(WP1/16), a liaison reply from SG15 provides the ANT (Access Network Transport)standardization plan issue 1, October, 1998. TD-44(PLEN) includes Q23/16’s reply. It providesmodifications to the entry pertaining to Rec. V.90 and notes that V.91 is now Approved.
TD-5(WP1/16) is a liaison statement from SG15 on “network characteristics” for information.Two major points are addressed: CME (Circuit Multiplication Equipment) from Q6/15, andInterworking from Q8/15.
Q6/15 is currently studying the method to convey higher-bit-rate modem signals, such as V.34 orV.90. There are two methods envisaged. The first is to use 64 kbit/s clear channels for VBDsignals instead of 40 kbit/s coded channel, with an attendant sacrifice of CME channel efficiency.The second method is to discriminate incoming higher-bit-rate modem signals from conventionallower-bit-rate modem signals and assign 64kbit/s clear channels only for the higher-bit-ratesignals.
Q8/15 notes the widespread use of digital pads on the order of 3-6 dB on virtually every inter-switch call and the attendant degradation this causes V.90 modems. It also notes that manyPT&Ts have chosen to implement the digital trunk connections between the local switching officeand the ISP without digital padding. TD-44(PLEN) provides the Q23/16 liaison response toQ6/15 supporting the discrimination of higher-bit-rate modems.
TD-7(WP1/16) is a liaison reply from SG15 responding to the Q23/16 request to clarify theadaptive component of build-out delay. Delays in PCME (G.764 and G.765) consist of mainly twocomponents: a fixed delay and a variable delay. The fixed delay arises from signal propagationon the transmission link and fixed processing delays. Variable delays result primarily from thequeuing and processing of packets. The maximum allowable variable delay for a virtual path orvirtual circuit is specified as the build-out. The terminating endpoint must therefore store thevoice band packets (data or speech) that arrive before their scheduled play-out time and playthem at regular intervals. Packets exceeding the build-out delay are considered late and aredropped. The build-out delay is added only once at the terminating endpoint. Therefore the build-out delay is a fixed delay. In order to avoid future confusion, clarifying text was added notingthat build-out delay can be set by the operator in accordance with I.356 to a value between 300microsec. and 3 millisec. in 100 microsec. steps. Q23/16 agreed that no further liaison isnecessary at this time.
TD-8(WP1/16) from Q5/SG2 raises questions on the operation of V.34 and the operation of V.34for fax. Attached is draft E.hispeed (10/11/98), Measurements and metrics for monitoring theperformance of V.34 G3 facsimile. The liaison reply (in TD-44(PLEN)) provides the requestedinformation on V.34, noting that it is feasible to demodulate the control channel; it notes that theV.34 MPh sequence can occur during initial start-up, inter page data rate signaling changes, andcontrol channel retrains.
PCM MODEM ISSUES LIST
Q23/16 approved TD-23(WP1/16), the issues list for the on-going work on PCM modems updatedto reflect the agreements reached at the Q23/16 Rapporteur meeting in San Diego, California.
The following companies indicated verbally that they may have IP pertaining to draftRecommendation V.91 and either have submitted or plan to submit patent statements: Conexant,3Com, Lucent Technologies, Motorola and MGCS Panasonic. The following companies havemade similar verbal statements at previous meetings: Matsushita and Lake Datacomms.
FUTURE MEETINGS
Two interim Rapporteur meetings are planned to progress the work of Q23/16. These meetingswill be held jointly with the Q8/16 and Q23/16 Rapporteur Groups. The meetings are scheduledfor Sept. 13-17, 1999 in Belgium, and for Jan. 10-14, 2000 in Ft. Lauderdale, FL.
Austria Gerhard ListAustria Telekom Austria Bernard HandlAustria Telekom Austria Klaus SamborAustria Telekom Austria Andreas SteinerAustria Telekom Austria Michael WelserBelgium Telindus NV Paul AertsBrazil Georges ClaessonBrazil Maximiliano Martinh˜ñoCanada Roch LefebvreCanada Redwan SalamiCanada Tom TaylorCanada Mitel David WalkerCanada Nortel Networks (Canada) François AudetCanada Nortel Networks (Canada) Peter YueChile Entel, S.A Mauricio Castillo RebolledoChile Entel, S.A Mauricio Andres Grandon AravenaChina Xiao Hui DaiChina Lin Tao JiangChina Xing Ming LiChina Xin Yue LiuChina Guo Wen SongChina Yuezheng WenChina Yun Tao XuChina Hong Bin YuFinland Marko LuomiFinland Helsinki Telephone Co. Juha Kauppi
Finland Nokia Ari HeikkinenFinland Nokia Kim NordlundFinland Nokia Pekka RissanenFinland Tellabs Oy Jerry SkeneFrance Jean Pierre BlinFrance Yves Robin-ChampigneulFrance Alcatel CIT Bahman MobasserFrance Alcatel CIT Nicolas TranFrance France Telecom Claude LamblinFrance France Telecom Franck LelongFrance Matra Nortel François CapmanGermany Rolf RôggebergGermany Istvan SebestyenGermany Bosch Jens VollmerGermany Deutsche Telekom Ralf-Rainer DammGermany Deutsche Telekom Joachim StegmannGermany Siemens Gero Base
Germany Siemens Robert CallaghanGermany Siemens Martin EuchnerGermany Siemens Neal KingGermany Siemens Karl KlaghoferGermany Siemens Juha KorpiGermany Siemens Markku KorpiGermany Siemens Bernard WimmerGermany TELES Jorg OttIndia Pradeep Kumar AgarwalIsrael Meir AgassyIsrael Orit LevinIsrael Boaz MichaelyIsrael Lior MoscoviciIsrael Sasha RuditskiIsrael Uzi ShalevItaly Mauro FalconeItaly Roberto FlaianiItaly CSELT Rosario Drogo De IacovoItaly CSELT Livio LambarelliItaly CSELT Federico ToscoJapan Kouichi IidaJapan Mitsuji MatsumotoJapan Sakae OkuboJapan Canon Masao HosakaJapan CIAJ Keiichi HibiJapan Fujitsu Yasuji OtaJapan Fujitsu Kiyoshi SakaiJapan Hitachi Toshiaki SuzukiJapan KDD Hideaki Yamada
Japan Matsushita Electric Industrial Akira AtsutaJapan Matsushita Electric Industrial Hiroyuki EharaJapan Mitsubishi Electric Kazuhiro MatsuzakiJapan Mitsubishi Electric Yushi NaitoJapan NEC Hidenobu HarasakiJapan NEC Masahiro SerizawaJapan NTT Shinji HayashiJapan NTT Naoki KobayashiJapan NTT Kazunori ManoJapan NTT Shigeaki SasakiJapan OKI Electric Industry Yasuo AoyagiJapan OKI Electric Industry Yasubumi ChimuraJapan OKI Electric Industry Minoru MiyazakiJapan Toshiba Barry AronsonJapan Toshiba Yoshihiro KikuchiJapan Toshiba Masahiro OshikiriJapan Toshiba Hirokazu TanakaKorea Don-Whan HyunKorea Samsung Electronics Doh-Suk Kim
Netherlands Royal KPN Jeroen De MuijnckSweden L.M. Ericsson Robert BaumlSweden L.M. Ericsson Christian GrovesSweden L.M. Ericsson Roar HagenSweden L.M. Ericsson Gunnar HellströmSweden L.M. Ericsson Goran RothSweden Telia Research Annika KilegranSwitzerland Swisscom Pierre-André ProbstUK John MagillUK Joseph PointerUK BT Paul BarrettUK BT John BoucherUK BT Morgan PotterUK Lucent Technologies Mike BuckleyUK Lucent Technologies Brian MooreUK Madge Networks Andrew DraperUSA Bruce De GrasseUSA Gary FerenoUSA Jeff HeathUSA Granger KelleyUSA James LordUSA An NguyenUSA Radhika RoyUSA Andrea SaksUSA Alan SharpleyUSA John TardelliUSA Benjamin WalstonUSA 3-COM Fred LucasUSA Alcatel, USA Clifford ThomasUSA Ameritech Services Fred KujawskiUSA Analog Devices Joshua KablotskyUSA Ascend Communications Gerard J. AguilarUSA Ascend Communications Dale SkranUSA Ascend Communications Robert ZopfUSA AT&T David KapilowUSA Cisco Systems Richard BowenUSA Cisco Systems Hascall SharpUSA COMSAT Corporation Simao Campos-NetoUSA COMSAT Corporation Suat YeldenerUSA Conexant Systems Keith T. ChuUSA Conexant Systems Tom GearyUSA Conexant Systems Jes ThyssenUSA Databeam Paul JonesUSA Databeam Patrick MuphyUSA Delta Information Systems Paul RandallUSA Dialogic Corporation Steven MagnellUSA ESS Technology Jordan CookmanUSA Intel Vineet KumarUSA Intel Gregory Meyer
USA Intel Mark R. WalkerUSA Lucent Technologies Robert AbramsUSA Lucent Technologies Rex ColdrenUSA Lucent Technologies Glen FreundlichUSA Lucent Technologies Milo OrsicUSA Lucent Technologies Sean RamprashadUSA Microsoft Gary SullivanUSA Motorola Info. Systems Bruce AdamsUSA Motorola Info. Systems Les BrownUSA Motorola Info. Systems Edgar MartinezUSA Motorola Info. Systems William SchmidtUSA Motorola Info. Systems Randall StewartUSA Motorola Info. Systems Qiaobing XieUSA PictureTel Antony CrossmanUSA PictureTel Kaynam HedayatUSA PictureTel George HelderUSA PictureTel Patrick LuthiUSA Qualcomm, Inc. Amitav DasUSA Qualcomm, Inc. Peter JacksonUSA Tekelec Virgil LongUSA Telcordia Technologies Hong Liu
USA Telcordia Technologies Michael RamalhoUSA Telcordia Technologies Richard RubinUSA Texas Instruments Jacek StachurskiUSA Texas Instruments Vishu ViswanathanUSA Videoserver Bryan HillUSA VTEL Smita GuptaUSA WorldCom Douglas Clowes
ITU-TSB Fabio BigiITU-TSB Gabrielle Regan
The next issue of Communications Standards Review - Telecommunications (Vol. 10 #7) isscheduled for August 1999.
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ACELP Adaptive CELPACF Authentication Control FunctionACR Absolute Category RatingAM Amplitude ModulationAMR Adaptive MultiRateANSI American National Standards InstituteARQ Automatic Repeat RequestASN Abstract Symbol NotationATM Asynchronous Transfer ModeATMF ATM ForumAV AudioVisualAVT Audio/Visual TransportBAS Bit rate Allocation SignalBER Bit Error Rate(B)FER Burst Frame Error RateBRQ Bandwidth RequestC&I Commands and IndicationsCCR Comparison Category RatingCDMA Code Division Multiple AccessCELP Code Excited Linear PredictionCIC Carrier Identification CodeCME Circuit Multiplication EquipmentCNI Comfort Noise InsertionCRC Cyclic Redundancy CodeCS-ACELP Conjugate Structure ACELPDCE Data Circuit terminating EquipmentDCME Digital Circuit Multiplication Eqpt.DCT Discrete Cosine TransformDQUANT Field for modified quantization mode (H.263+)DRQ Disengage RequestDS0 64 kbit/s ChannelDSP Digital Signal ProcessingDSS2 Digital Subscriber Signaling 2DTE Data Terminal EquipmentDTMF Dual Tone Multi FrequencyEDH Electronic Document HandlingEID Equipment IdentifierFIR Finite Impulse ResponseGII Global Information InfrastructureGK GateKeeperGSM Global System for Mobile CommunicationsGW GateWayHDLC High Level Data Link ControlHDTV High Definition TelevisionHSD High Speed Data ChannelIDCT Inverted Discrete Cosine TransformIETF Internet Engineering Task ForceIMT International Mobile Telecommunications (IMT-2000,)IMTC International Multimedia Teleconferencing ConsortiumIN Intelligent NetworkIP Internet ProtocolIPSEC IP Security (IETF)IPTEL Internet Protocol Telephony (IETF Working Group)IRS Intermediate Reference SystemISDN Integrated Services Digital NetworkISOC Internet SocietyISP Internet Service ProviderISUP ISDN User Part
ITU Int’l Telecommunication UnionJRG Joint Rapporteurs GroupLD CELP Low Delay CELPLSD Low Speed Data channelMCS Multi-point Control Services (T.122)MCU Multi-point Control UnitMCV Multipoint Command VisualizationMEGACO MEdia GAteway COntrolMG Media GatewayMGC Media Gateway ControllerMGCP Media Gateway Control ProtocolMIB Management Information BaseMIPS Million Instructions Per SecondMIV Multipoint Indication VisualizationMLP Multi-Layer ProtocolMOS Mean Opinion ScoreMOU Memorandum of UnderstandingMPEG Motion Picture Experts GroupMTP Multicast Transport ProtocolMUX MultiplexerOID Object IdentifierPCM Pulse Code ModulationPCME Packet Circuit Multiplication Eqpt.PDU Protocol Data UnitPINT PSTN Interworking (IETF)POTS Plain Old Telephone ServicePSTN Public Switched Telephone NetworkPT&T Public Telephone and TelegraphQOS Quality of ServiceRAS Registration, Admission, and StatusRFC Designation for an Internet StandardRTCP Real-time Transport Control ProtocolRTP Real Time Transport ProtocolSCN Switched Circuit NetworkSDP Session Description ProtocolSET Simple Endpoint TypesSG Study Group (ITU, CCITT)SQEG Speech Quality Expert GroupSS7 Signaling System 7STL Software Tool LibraryTA Terminal AdapterTCP Transmission Control ProtocolTIPHON Telecommunications and Internet Protocol Harmonization Over Networks (ETSI Project)TOR Terms of ReferenceTPKT Transport Packet (T.123)TSAG Telecommunication Standardization Advisory Group (ITU)TSB Telecommunications Standardization Board (ITU)UDP User Datagram ProtocolURL Uniform Resource LocatorVAD Voice Activity DetectorVBD Voice Band DataVBR Variable Bit RateVCI Virtual Channel IdentifierVLC Variable Length CodewordVoIP Voice Over Internet ProtocolVPI Virtual Path IdentifierWAP Wireless Application ProtocolWG Working Group
WMOPS Weighted MOPSWP Working Party (ITU)xDSL all the different Digital Subscriber Line equipment
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