1、INTERNATIONAL TELECOMMUNICATION UNION ITU-T TE LEC OM M U N i CAT I ON STAN DARD IZATI ON SECTOR OF ITU J .90 (OW200 O) SERIES J: TRANSMISSION OF TELEVISION, SOUND PROGRAMME AND OTHER MULTIMEDIA SIGNALS Ancillary digital services for television transmission Electronic programme guides for delivery b
2、y digital cable television and similar methods - Reference operating scenario and requirements ITU-T Recommendation J.90 (Formerly CCITT Recommendation) General Recommendations General specifications for analogue sound-programme transmission Performance characteristics of analogue sound-programme ci
3、rcuits Equipment and lines used for analogue sound-programme circuits Digital encoders for analogue sound-programme signals Digital transmission of sound-programme signals Circuits for analogue television transmission Analogue television transmission over metallic lines and interconnection with radi
4、o-relay links Digital transmission of television signals Ancillary digital seMe televisin transmission Operational requirements and methods for television transmission Interactive systems for digital television distribution Transport of WEG-2 signals on packetised networks Measurement of the quality
5、 of service Digital television distribution through local subscriber networks ITU-T J-SERIES RECOMMENDATIONS TRANSMISSION OF TELEVISION, SOUND PROGRAMME AND OTHER MULTIMEDIA SIGNALS For further details, please refer to the list of ITU-TRecommendaiions J.l-J.9 J. 10-J.19 J.20-J.29 5.30-J.39 J.40-J.49
6、 J.50-J.59 J.60-J.69 J.70-J.79 J.80-J.89 J.90s.99 J. 100-J. 109 J.llO-J.129 J.130-J.139 J. 140-J. 149 J.150-J.159 ITU-T Recommendation J.90 Electronic programme guides for delivery by digital cable television and similar methods - Reference operating scenario and requirements Summary This Recommenda
7、tion specifies a reference operating scenario and a number of requirements applicable to Electronic Programme Guide (EPG) information delivered to the home by digital cable television and other similar distribution methods. Delivery of EPG information may be implemented through various operating sce
8、narios; a typical scenario is described in Appendix I by way of an example and to serve as a reference. The importance of properly structured EPGs in which home viewers can readily navigate is becoming increasingly important with the current large increase in the number of programmes offered to the
9、home, which is made possible by digital television delivery systems that employ bit rate reduction. This Recommendation is meant to catalyse the .development of an efficient structure for EPG information, conducive to user-friendly interactive navigation tools that will help viewers to find their wa
10、y among EPG information. Source ITU-T Recommendation J.90 was revised by ITU-T Study Group 9 (1 997-2000) and approved under the WTSC Resolution 1 procedure on 18 May 2000. FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunica
11、tions. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunicati
12、on Standardization Conference (WTSC), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSC Resolution 1. In some areas of i
13、nformation technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with IS0 and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating
14、agency. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Proper
15、ty Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, impl
16、ementors are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database. O ITU 2001 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including ph
17、otocopying and microfilm, without permission in writing from ITU. CONTENTS 1 2 3 4 4.1 4.2 4.3 4.4 4.5 4.6 4.7 5 Scope Nonnative references Terms, definitions and acronyms . Discussion on Electronic Programme Guides for delivery by digital cable television . Information to be provided by EPGs Labell
18、ing of EPG information Conditional access Delivery of EPG information to the home . Presenting EPG information on consumer receivers Considerations on interoperability Refiesh rates . Summary of guidelines and specifications . Page 1 1 1 2 2 3 3 4 4 4 5 6 Appendix I - Example of an operating scenari
19、o for the generation, assembly and delivery of EPG information . 6 I. 1 Introduction 6 1.2 Sourcing EPG information . 6 1.3 . Assembling EPG information . 7 I;5: , Presenting EPG information . 7 7 . . 14. . ., Delivenng EPG information . ,. I .I : .i 1 .; 8 - :, . . ,i Appendix II - Bibliography . 1
20、. . ITU-T Recommendation J.90 Electronic programme guides for delivery by digital cable television and similar methods - Reference operating scenario and requirements 1 Scope This Recommendation specifies a reference operating scenario and a number of requirements applicable Electronic Programme Gui
21、des (EPGs) delivered to the home by digital cable television and other similar distribution methods. The specified approach is based on the identification of the various items of information that should be delivered to the home; those items of information may be divided into categories having differ
22、ent degrees of importance or delivery priorities, and identification codes must be used for them, to allow unequivocal retrieval upon reception. Although the scope of this Recommendation is focused on EPG delivery over digital channels, its main operational concepts, and the structure for EPGs based
23、 on them are generally also applicable to EPGs delivered by teletext over analogue television channels. A typical operating scenario is described in Appendix I as an example of the way the generation, assembly and delivery of EPG information may be organised. This scenario is taken as a reference in
24、 the presentation of the Recommendation. This Recommendation does not cover the mechanism to download EPG information on user request (Le. interactive applications), nor the labelling of the various components in the WEG-2 (i of Appendix II) bit stream used to deliver digital television to the home:
25、 it just specifies the reference operating scenario and a number of user requirements for EPGs. Individual labelling of the various items of EPG information carried in the bit stream is specified in clause 2/J.94 i, Service information for digital broadcasting in cable television systems. Normative
26、references following ITU-T Recommendations and other references contain provisions which, through ce in this text, constitute provisions of this Recommendation. At the time of publication, the s indicated were valid. All Recommendations and other references are subject to revision; Recommendation ar
27、e therefore encouraged to investigate the possibility of applying the edition of the Recommendations and other references listed below. A list of the currently -T Recommendations is regularly published. ITU-T J.94 (1 998), Service information for digital broadcasting in cable television systems. 3 T
28、erms, definitions and acronyms ause lists some specific terms, definitions and acronyms used in this Recommendation. application-free EPG: An EPG in which the provider can freely select the content and the of the presentation, in a way that is implemented by the consumer televisiodmultimedia capacit
29、y provider: The entity that provides the technical facilities needed to deliver a display. 3.2 programme schedule (e.g. the common carrier). 3.3 consumer premises equipment provider: The entity that supplies the televisiodmultimedia equipment at the consumer premises (e.g. the equipment manufacturer
30、). 3.4 programme producer or the owner of its rights). 3.5 information on programmes to be broadcast or cablecast. 3.6 EPG: Electronic Programme Guide. 3.7 that constitute the EPG database. 3.8 operation of the consumer televisiodmultimedia display is not. 3.9 sequenced on a delivery channel (e.g. t
31、he broadcaster). 3.10 distribution service, to which a specific programme should be distributed. content provider: The entity that provides the creative content of a programme (e.g. the electronic programme guide: A structured multimedia database, intended to provide EPG provider: The entity that co
32、llects, collates and assembles the elements of information presentation-free EPG: An EPG for which the information content is specified, but the schedule provider: The entity that decides the schedule in which programmes are area availability code: A code used to denote that part of the area covered
33、 by a programme 4 Discussion on Electronic Programme Guides for delivery by digital cable television 4.1 EPGs should preferably provide the following “basic“ items of information, concerning the content of each delivered programme: Information to be provided by EPGs O programme title and subtitle or
34、 episode title; programme category (drama, sports, news, etc.); parental rating (children, adult, etc.); area availability code (blackout identification information); talent (director, cast, photographer, music, author, etc.); O O O programme duration; O producer; O date of production; O short text
35、summary of the programme; technical format (wide screen, stereo sound, etc.). O EPGs may also optionally provide the following supplementary items of information on each delivered programme: O long text summary of the programme; O press reviews; O press/critics rating, if available; O photos of the
36、leading performers; photos of posters, if available; O O stage photos; O video clips or “teasers“; O music excerpts or “teasers“; 1 The content-related information and the delivery-related information listed in this clause are not necessarily arranged in order of importance, nor in the order in whic
37、h they should be displayed. e production company; e production facility; a production staff; a intellectual property rights; e copyright aspects; e others. l EPGs should preferably provide the following “basic“ items of information, concerning the delivery of each offered programme: a designation of
38、 the broadcast or cable channel; e day and time of broadcast; first screening on TV, repeat screening, etc.; ancillary services: subtitling, audio for the hearing-impaired, etc.; information on access entitlement, if any; codes to programme automatic video recording, etc. e e e e It is clear fi-om t
39、he lists above that EPG information can be described as a multimedia database. 4.2 Labelling of EPG information Every item of EPG information delivered to the home must be labelled in a unique way, in order that it may be unequivocally retrieved and processed in the home. The objective is to allow c
40、onsumers at home to freely navigate through the EPG information if their receiver has adequate intelligence and memory. This Recommendation does not speci the label or the data length for EPG infomation. Such labelling is specified in clause 2/J.94 i, Service information for digital broadcasting in
41、cable television systems. 4.3 Conditional access Delivery of EPGs is likely to be subjected to some degree of conditional access. A consumer that wishes to receive basic information on all programmes as a separate service is likely ready to pay for it. The mechanism for conditional access in this ca
42、se may be similar to the one used for conditional access in television subscription services (see ITU-T J.93, Requirements for conditional access in the secondary distribution of digital television on cable television systems, 4 in Appendix II). Delivery of EPG information to professional parties is
43、 also generally subject to conditional access. In this respect different professional parties are generally granted different degrees of access. For instance, “write“ access is generally only granted to some selected parts of the EPG multimedia database, while “read-only“ access is more generally gr
44、anted. Specifically, schedule providers are generally granted write access only to information that concerns programmes on their channels. Other professional parties such as publishers of printed programme guides may well be willing to pay a “professional“ subscription fee to be entitled to receive
45、the complete content of the EPG multimedia database and to print selected parts of it. It is obvious that the EPG multimedia database must have adequate capacity to carry conditional access information for each part of it. 4.4 Digital delivery of EPGs to the home amounts to downloading a digital mul
46、timedia application to the user. Since digital delivery of television to the home is based on the delivery of MPEG-2 transport streams, the logical choice for delivering EPGs to the home is to use that part of the capacity in the MPEG-2 transport stream that is set aside for data delivery. EPG deliv
47、ery in the MPEG-2 multiplex must obviously comply with the protocols specified for assembling a MPEG-2 transport stream. This Recommendation does not cover those protocols. If it is not possible to set aside a sufficiently large capacity for EPG delivery in the capacity for data of the MPEG-2 transp
48、ort stream, then only selected parts of the EPG database will be delivered in it. Delivery of the remaining parts of the database to the home will then require the use of some shared data capacity available in the delivery channel, outside the MPEG-2 transport stream. Standardisation of protocols fo
49、r the management of the data capacity of a delivery channel is under study; some specifications already exist in regional standards. Another approach may be to apply compression to the EPG database in order to achieve more efficient transmission and storage. Several algorithms exist for this purpose. If such an approach is used for the EPG database, then a compatible algorithm to expand the database needs to be provided in the consumer receiver. Modulation of EPG data in view of its delivery to the home in the MPEG-2 transport stream must obviously comply with the modu
