1、 International Telecommunication Union ITU-T J.181TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (01/2014) SERIES J: CABLE NETWORKS AND TRANSMISSION OF TELEVISION, SOUND PROGRAMME AND OTHER MULTIMEDIA SIGNALS Digital transmission of television signals Digital program insertion cueing message for ca
2、ble television systems Recommendation ITU-T J.181 Rec. ITU-T J.181 (01/2014) i Recommendation ITU-T J.181 Digital program insertion cueing message for cable television systems Summary Recommendation ITU-T J.181 supports frame accurate signalling of events in MPEG-2 transport streams along with assoc
3、iated descriptive data. This Recommendation supports the splicing of MPEG-2 transport streams for the purpose of digital program insertion, which includes advertisement insertion and insertion of other content types. An in-stream messaging mechanism is defined to signal splicing and insertion opport
4、unities and it is not intended to ensure seamless splicing. As such, this Recommendation does not specify the splicing method used or constraints applied to the streams being spliced, nor does it address constraints placed on splicing devices. A fully compliant MPEG-2 transport stream (either multi
5、program transport stream (MPTS) or single program transport stream (SPTS) is assumed. No further constraints beyond the inclusion of the defined cueing messages are placed upon the stream. This Recommendation specifies a technique for carrying notification of upcoming Splice Points and other timing
6、information in the transport stream. A splice information table is defined for notifying downstream devices of splice events, such as a network break or return from a network break. The splice information table, which pertains to a given program, is carried in one or more PID(s) referred to by that
7、programs program map table (PMT). In this way, splice event notification can pass through most transport stream remultiplexers without need for special processing. History Edition Recommendation Approval Study Group Unique ID*1.0 ITU-T J.181 2001-03-09 9 11.1002/1000/5386-en 1.1 ITU-T J.181 (2001) A
8、md. 1 2003-04-04 9 11.1002/1000/6355-en 2.0 ITU-T J.181 2004-06-29 9 11.1002/1000/7379-en 3.0 ITU-T J.181 2014-01-13 9 11.1002/1000/12102-en _ *To access the Recommendation, type the URL http:/handle.itu.int/ in the address field of your web browser, followed by the Recommendations unique ID. For ex
9、ample, http:/handle.itu.int/11.1002/1000/11830-en. ii Rec. ITU-T J.181 (01/2014) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standard
10、ization 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 Telecommunication Standardization Assembly (WTSA), which
11、 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 WTSA Resolution 1. In some areas of information technology which fall within ITU
12、-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation
13、 is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “mus
14、t“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation ma
15、y involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of thi
16、s Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementers are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent data
17、base at http:/www.itu.int/ITU-T/ipr/. ITU 2014 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T J.181 (01/2014) iii Table of Contents Page 1 Scope 1 2 References. 1 3 Definitions 2 3.1 Terms defined e
18、lsewhere 2 3.2 Terms defined in this Recommendation . 2 4 Abbreviations and acronyms 4 5 Conventions 5 6 Introduction 5 6.1 Splice points (Informative) . 5 6.2 Program splice points (Informative) . 6 6.3 Splice events (Informative) 6 6.4 Content storage considerations (Informative) 6 6.5 PID selecti
19、on 7 6.6 Message flow (Informative) . 8 7 XML notational conventions 8 7.1 Normative XML schema 8 7.2 Unknown/unrecognized/unsupported XML elements and attributes . 9 7.3 Element order . 9 8 PMT descriptors . 9 8.1 Registration descriptor 9 8.2 Cue identifier descriptor . 10 8.3 Stream identifier de
20、scriptor 11 9 Splice information table 12 9.1 Overview 12 9.2 Splice info section 13 9.3 Splice commands 18 9.4 Constraints 29 10 Splice descriptors 31 10.1 Overview 31 10.2 Splice descriptor . 31 10.3 Specific splice descriptors 33 11 Encryption 46 11.1 Overview 46 11.2 Fixed key encryption 46 11.3
21、 Encryption algorithms 46 12 SCTE 35 XML elements and types 47 12.1 Ext element . 47 iv Rec. ITU-T J.181 (01/2014) Page 12.2 PTSType . 48 Appendix I CableLabs metadata identifier . 49 Bibliography. 50 Rec. ITU-T J.181 (01/2014) 1 Recommendation ITU-T J.181 Digital program insertion cueing message fo
22、r cable television systems 1 Scope This Recommendation supports frame accurate signalling of events in MPEG-2 transport streams along with associated descriptive data. This Recommendation supports the splicing of MPEG-2 transport streams for the purpose of Digital Program Insertion, which includes a
23、dvertisement insertion and insertion of other content types. An in-stream messaging mechanism is defined to signal splicing and insertion opportunities and it is not intended to ensure seamless splicing. As such, this Recommendation does not specify the splicing method used or constraints applied to
24、 the streams being spliced, nor does it address constraints placed on splicing devices. A fully compliant MPEG-2 transport stream (either multi program transport stream (MPTS) or single program transport stream (SPTS) is assumed. No further constraints beyond the inclusion of the defined cueing mess
25、ages are placed upon the stream. This Recommendation specifies a technique for carrying notification of upcoming Splice Points and other timing information in the transport stream. A splice information table is defined for notifying downstream devices of splice events, such as a network break or ret
26、urn from a network break. The splice information table, which pertains to a given program, is carried in one or more packet identifiers (PIDs) referred to by that programs program map table (PMT). In this way, splice event notification can pass through most transport stream remultiplexers without ne
27、ed for special processing. 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other refere
28、nces are subject to revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The reference t
29、o a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. ITU-T H.222.0 Recommendation ITU-T H.222.0 (2012) | ISO/IEC 13818-1:2013, Information Technology Generic coding of moving pictures and associated audio information: Systems. IETF RFC
30、3986 IETF RFC 3986 (2005), Uniform Resource Identifier (URI): Generic Syntax, www.ietf.org/rfc/rfc3986.txt/ ISO 15706-2 ISO 15706-2:2007 Information and documentation International Standard Audiovisual Number (ISAN) Part 2: Version identifier. ATSC A/57B ATSC A/57B ATSC Standard: Content Identificat
31、ion and Labeling for ATSC Transport Document A/57B, 26 May 2008. FIPS PUB 46-3 FIPS PUB 46-3, Data Encryption Standard (DES), 25 October 1999. FIPS PUB 81 FIPS PUB 81, DES Modes of Operation, 2 December 1980. SMPTE 330M SMPTE 330M-2004 SMPTE Standard for Television Unique Material Identifier. XML W3
32、C, Extensible Markup Language (XML) 1.0 (Fourth Edition), W3C Recommendation 16 August 2006, http:/www.w3.org/TR/2006/REC-xml-20060816/ 2 Rec. ITU-T J.181 (01/2014) XMLInfoSet W3C, XML Information Set (Second Edition), W3C Recommendation, 4 February 2004, http:/www.w3.org/TR/2004/REC-xml-infoset-200
33、40204/ 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the following terms defined elsewhere: 3.1.1 pointer_field ITU-T H.222.0: The first byte of a transport packet payload, required when a section begins in that packet. 3.1.2 presentation unit (PU) ITU-T H.222.0: A decoded audio
34、 access unit or a decoded picture. 3.1.3 uniform resource identifier (URI): See IETF RFC 3986. 3.1.4 extensible markup language (XML): See XML. 3.2 Terms defined in this Recommendation This Recommendation defines the following terms: 3.2.1 access unit: A coded representation of a presentation unit.
35、3.2.2 advertisement (also called “ad“): An inducement to buy or patronize. As used in the cable industry, usually with a duration under 2 minutes (sometimes called “short-form“ content). 3.2.3 analogue cue tone: In an analogue system, a signal that is usually either a sequence of dual tone multi-fre
36、quency (DTMF) tones or a contact closure that denotes to ad insertion equipment that an advertisement avail is about to begin or end. 3.2.4 avail: Time space provided to cable operators by cable programming services during a program for use by the community antenna television (CATV) operator; the ti
37、me is usually sold to local advertisers or used for channel self promotion. 3.2.5 bit stream format: An encoding of information resulting in a compliant MPEG-2 transport stream. 3.2.6 break: Avail or an actual insertion in progress. 3.2.7 chapter: A short section of a longer program, usually situate
38、d to permit a viewer to easily locate a scene or section of the program. 3.2.8 component splice mode: A mode of the cueing message whereby the program_splice_flag is set to 0 and indicates that each PID/component that is intended to be spliced will be listed separately by the syntax that follows. Co
39、mponents not listed in the message are not to be spliced. 3.2.9 content: Generic term for television material, either advertisements or programs. 3.2.10 cueing message: See message. 3.2.11 event: A splice event or a viewing event. 3.2.12 in point: A point in the stream, suitable for entry, that lies
40、 on an elementary presentation unit boundary. An in point is actually between two presentation units rather than being a presentation unit itself. 3.2.13 in stream device: A device that receives the transport stream directly and is able to derive timing information directly from the transport stream
41、. 3.2.14 message: In the context of this Recommendation a message is the contents of any splice_info_section. Rec. ITU-T J.181 (01/2014) 3 3.2.15 multi program transport stream: A transport stream with multiple programs. 3.2.16 out of stream device: A device that receives the cue message from an in
42、stream device over a separate connection from the transport stream. An out of stream device does not receive or pass the transport stream directly. 3.2.17 out point: A point in the stream, suitable for exit, that lies on an elementary presentation unit boundary. An out point is actually between two
43、presentation units rather than being a presentation unit itself. 3.2.18 packet identifier (PID): A unique 13-bit value used to identify the type of data stored in the packet payload. 3.2.19 payload_unit_start_indicator: A bit in the transport packet header that signals, among other things, that a se
44、ction begins in the payload that follows. 3.2.20 PID stream: All the packets with the same PID within a transport stream. 3.2.21 presentation time: The time that a presentation unit is presented in the system target decoder. 3.2.22 presentation unit: A decoded Audio Access Unit or a decoded picture
45、(see b-ITU-T H.262). 3.2.23 program: A collection of video, audio, and data PID streams that share a common program number within an MPTS (see ITU-T H.222.0). As used in the context of the segmentation descriptor, a performance or informative presentation broadcast on television, typically with a du
46、ration over 5 minutes (sometimes called “long-form“ content). 3.2.24 program in point: A group of PID stream in points that correspond in presentation time. 3.2.25 program out point: A group of PID stream out points that correspond in presentation time. 3.2.26 program splice mode: A mode of the cuei
47、ng message whereby the program_splice_flag is set to 1 and indicates that the message refers to a Program Splice Point and that all PIDs/components of the program are to be spliced. 3.2.27 program splice point: A program in point or a program out point. 3.2.28 receiving device: A device that receive
48、s or interprets sections conforming to this Recommendation. Examples of these devices include splicers, ad servers, segmenters and satellite receivers. 3.2.29 registration descriptor: Carried in the program map table (PMT) of a program to indicate that, when signalling splice events, splice_info_sec
49、tions shall be carried in a PID stream within this program. The presence of the Registration Descriptor signifies a programs compliance with this Recommendation. 3.2.30 reserved: The term “reserved“, when used in the clauses defining the coded bit stream, indicates that the value may be used in the future for extensions to the Recommendation. Unless otherwise specified, all reserved bits shall be set to 1 and this field shall be ignored by receiving equipment. 3.2.31 segment: Either
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