1、 ETSI TS 1Universal Mobile TelTranPacket switchTi(3GPP TS 26.2TECHNICAL SPECIFICATION126 245 V13.0.0 (2016elecommunications System (LTE; ansparent end-to-end c ed Streaming Service (PSS)Timed text format .245 version 13.0.0 Release 1316-01) (UMTS); S); 13) ETSI ETSI TS 126 245 V13.0.0 (2016-01)13GPP
2、 TS 26.245 version 13.0.0 Release 13Reference RTS/TSGS-0426245vd00 Keywords LTE,UMTS ETSI 650 Route des Lucioles F-06921 Sophia Antipolis Cedex - FRANCE Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16 Siret N 348 623 562 00017 - NAF 742 C Association but non lucratif enregistre la Sous-Prfecture de G
3、rasse (06) N 7803/88 Important notice The present document can be downloaded from: http:/www.etsi.org/standards-search The present document may be made available in electronic versions and/or in print. The content of any electronic and/or print versions of the present document shall not be modified
4、without the prior written authorization of ETSI. In case of any existing or perceived difference in contents between such versions and/or in print, the only prevailing document is the print of the Portable Document Format (PDF) version kept on a specific network drive within ETSI Secretariat. Users
5、of the present document should be aware that the document may be subject to revision or change of status. Information on the current status of this and other ETSI documents is available at http:/portal.etsi.org/tb/status/status.asp If you find errors in the present document, please send your comment
6、 to one of the following services: https:/portal.etsi.org/People/CommiteeSupportStaff.aspx Copyright Notification No part may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm except as authorized by written permission of ETSI. The
7、content of the PDF version shall not be modified without the written authorization of ETSI. The copyright and the foregoing restriction extend to reproduction in all media. European Telecommunications Standards Institute 2016. All rights reserved. DECTTM, PLUGTESTSTM, UMTSTMand the ETSI logo are Tra
8、de Marks of ETSI registered for the benefit of its Members. 3GPPTM and LTE are Trade Marks of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners. GSM and the GSM logo are Trade Marks registered and owned by the GSM Association. ETSI ETSI TS 126 245 V13.0.0 (2016-0
9、1)23GPP TS 26.245 version 13.0.0 Release 13Intellectual Property Rights IPRs essential or potentially essential to the present document may have been declared to ETSI. The information pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
10、 in ETSI SR 000 314: “Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in respect of ETSI standards“, which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web server (https:/ipr.etsi.org/). Pursuant to the ETSI IPR Poli
11、cy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web server) which are, or may be, or may become, essential to the present document. Foreword This Tech
12、nical Specification (TS) has been produced by ETSI 3rd Generation Partnership Project (3GPP). The present document may refer to technical specifications or reports using their 3GPP identities, UMTS identities or GSM identities. These should be interpreted as being references to the corresponding ETS
13、I deliverables. The cross reference between GSM, UMTS, 3GPP and ETSI identities can be found under http:/webapp.etsi.org/key/queryform.asp. Modal verbs terminology In the present document “shall“, “shall not“, “should“, “should not“, “may“, “need not“, “will“, “will not“, “can“ and “cannot“ are to b
14、e interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of provisions). “must“ and “must not“ are NOT allowed in ETSI deliverables except when used in direct citation. ETSI ETSI TS 126 245 V13.0.0 (2016-01)33GPP TS 26.245 version 13.0.0 Release 13Contents
15、 Intellectual Property Rights 2g3Foreword . 2g3Modal verbs terminology 2g3Foreword . 4g3Introduction 4g31 Scope 5g32 References 5g33 Definitions and abbreviations . 6g33.1 Definitions 6g33.2 Abbreviations . 6g34 Overview 6g35 Timed text format . 6g35.1 Unicode Support . 6g35.2 Bytes, Characters, and
16、 Glyphs 7g35.3 Character Set Support . 7g35.4 Font Support . 7g35.5 Fonts and Metrics . 7g35.6 Colour Support . 8g35.7 Text rendering position and composition . 8g35.8 Marquee Scrolling 10g35.9 Language 11g35.10 Writing direction 11g35.11 Text wrap 11g35.12 Highlighting, Closed Caption, and Karaoke
17、. 11g35.13 Media Handler 11g35.14 Media Handler Header . 12g35.15 Style record 12g35.16 Sample Description Format 12g35.17 Sample Format . 14g35.17.1 Sample Modifier Boxes 14g35.17.1.1 Text Style 14g35.17.1.2 Highlight . 14g35.17.1.3 Dynamic Highlight 15g35.17.1.4 Scroll Delay. 15g35.17.1.5 HyperTex
18、t . 16g35.17.1.6 Textbox . 16g35.17.1.7 Blink 16g35.17.1.8 Text Wrap Indication 16g35.17.1.9 Stereo Disparity . 17g35.18 Combinations of features 17g3Annex A (informative): Change history . 19g3History 20g3ETSI ETSI TS 126 245 V13.0.0 (2016-01)43GPP TS 26.245 version 13.0.0 Release 13Foreword This T
19、echnical Specification has been produced by the 3rdGeneration Partnership Project (3GPP). The contents of the present document are subject to continuing work within the TSG and may change following formal TSG approval. Should the TSG modify the contents of the present document, it will be re-release
20、d by the TSG with an identifying change of release date and an increase in version number as follows: Version x.y.z where: x the first digit: 1 presented to TSG for information; 2 presented to TSG for approval; 3 or greater indicates TSG approved document under change control. y the second digit is
21、incremented for all changes of substance, i.e. technical enhancements, corrections, updates, etc. z the third digit is incremented when editorial only changes have been incorporated in the document. The 3GPP transparent end-to-end packet-switched streaming service (PSS) specification consists of six
22、 3GPP TSs: 3GPP TS 22.233 1, 3GPP TS 26.233 2, 3GPP TS 26.234 3, 3GPP TS 26.244 4, 3GPP TS 26.246 5 and the present document. The TS 22.233 contains the service requirements for the PSS. The TS 26.233 provides an overview of the PSS. The TS 26.234 provides the details of protocol and codecs used by
23、the PSS. The TS 26.244 defines the 3GPP file format (3GP) used by the PPS and MMS services. The TS 26.246 defines the 3GPP SMIL language profile. The present document defines the Timed text format used by the PSS. The TS 26.244, TS 26.245 (present document) and TS 26.246 start with Release 6. Earlie
24、r releases of the 3GPP file format, the Timed text format and the 3GPP SMIL language profile can be found in TS 26.234. Introduction Timed text is text that is rendered at the terminal, in synchronization with other timed media such as video or audio. Timed text is used for such applications as clos
25、ed captioning, titling, and other visual annotation of timed media. ETSI ETSI TS 126 245 V13.0.0 (2016-01)53GPP TS 26.245 version 13.0.0 Release 131 Scope The present document defines the timed text format relative to the 3GPP file format. This specification defines the format of timed text in downl
26、oaded files. 2 References The following documents contain provisions which, through reference in this text, constitute provisions of the present document. References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific. For a specific referenc
27、e, subsequent revisions do not apply. For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document. 1 3
28、GPP TS 22.233: “Transparent End-to-End Packet-switched Streaming Service; Service aspects; Stage 1“. 2 3GPP TS 26.233: “Transparent end-to-end packet switched streaming service (PSS); General description“. 3 3GPP TS 26.234: “Transparent end-to-end packet switched streaming service (PSS); Protocols a
29、nd codecs“. 4 3GPP TS 26.244: “Transparent end-to-end packet switched streaming service (PSS); 3GPP file format (3GP)“. 5 3GPP TS 26.246: “Transparent end-to-end packet switched streaming service (PSS); 3GPP SMIL Language Profile“. 6 3GPP TR 21.905: “Vocabulary for 3GPP Specifications“. 7 The Unicod
30、e Consortium: “The Unicode Standard“, Version 3.0 Reading, MA, Addison-Wesley Developers Press, 2000, ISBN 0-201-61633-5. 8 “Unicode Standard Annex #13: Unicode Newline Guidelines“, by Mark Davis. An integral part of The Unicode Standard, Version 3.1. 9 ISO/IEC 14496-14:2003 “Information technology
31、Coding of audio-visual objects Part 14: MP4 file format“. 10 ETSI EN 300 743 v1.4.1“Digital Video Broadcasting (DVB); Subtitling systems“. ETSI ETSI TS 126 245 V13.0.0 (2016-01)63GPP TS 26.245 version 13.0.0 Release 133 Definitions and abbreviations 3.1 Definitions For the purposes of the present do
32、cument, the following terms and definitions apply: continuous media: media with an inherent notion of time. In the present document speech, audio, video and timed text discrete media: media that itself does not contain an element of time. In the present document all media not defined as continuous m
33、edia PSS client: client for the 3GPP packet switched streaming service based on the IETF RTSP/SDP and/or HTTP standards, with possible additional 3GPP requirements according to the present document PSS server: server for the 3GPP packet switched streaming service based on the IETF RTSP/SDP and/or HT
34、TP standards, with possible additional 3GPP requirements according to the present document 3.2 Abbreviations For the purposes of the present document, the abbreviations given in 3GPP TR 21.905 6 and the following apply. 3GP 3GPP file format MMS Multimedia Messaging Service MP4 MPEG-4 file format PSS
35、 Packet-switched Streaming Service SMIL Synchronised Multimedia Integration Language UTF-8 Unicode Transformation Format (the 8-bit form) UTF-16 Unicode Transformation Format (the 16-bit form) 4 Overview Operators may specify additional rules and restrictions when deploying terminals, in addition to
36、 this specification, and behavior that is optional here may be mandatory for particular deployments. In particular, the required character set is almost certainly dependent on the geography of the deployment. 5 Timed text format 5.1 Unicode Support Text in this specification uses the Unicode 3.0 7 s
37、tandard. Terminals shall correctly decode both UTF-8 and UTF-16 into the required characters. If a terminal receives a Unicode code, which it cannot display, it shall display a predictable result. It shall not treat multi-byte UTF-8 characters as a series of ASCII characters, for example. Authors sh
38、ould create fully-composed Unicode; terminals are not required to handle decomposed sequences for which there is a fully-composed equivalent. Terminals shall conform to the conformance statement in Unicode 3.0 section 3.1. Text strings for display and font names are uniformly coded in UTF-8, or star
39、t with a UTF-16 BYTE ORDER MARK (uFEFF) and by that indicate that the string which starts with the byte order mark is in UTF-16. Terminals shall recognise the byte-order mark in this byte order; they are not required to recognise byte-reversed UTF-16, indicated by a byte-reversed byte-order mark. ET
40、SI ETSI TS 126 245 V13.0.0 (2016-01)73GPP TS 26.245 version 13.0.0 Release 135.2 Bytes, Characters, and Glyphs This clause uses these terms carefully. Since multi-byte characters are permitted (i.e. 16-bit Unicode characters), the number of characters in a string may not be the number of bytes. Also
41、, a byte-order-mark is not a character at all, though it occupies two bytes. So, for example, storage lengths are specified as byte-counts, whereas highlighting is specified using character offsets. It should also be noted that in some writing systems the number of glyphs rendered might be different
42、 again. For example, in English, the characters “fi“ are sometimes rendered as a single ligature glyph. In this specification, the first character is at offset 0 in the string. In records specifying both a start and end offset, the end offset shall be greater than or equal to the start offset. In ca
43、ses where several offset specifications occur in sequence, the start offset of an element shall be greater than or equal to the end offset of the preceding element. 5.3 Character Set Support All terminals shall be able to render Unicode characters in these ranges: a) basic ASCII and Latin-1 (u0000 t
44、o u00FF), though not all the control characters in this range are needed; b) the Euro currency symbol (u20AC) c) telephone and ballot symbols (u260E through u2612) Support for the following characters is recommended but not required: a) miscellaneous technical symbols (u2300 through u2335) b) “Zapf
45、Dingbats“: locations u2700 through u27AF, and the locations where some symbols have been relocated (e.g. u2605, Black star). The private use characters u0091 and u0092, and the initial range of the private use area uE000 through uE0FF are reserved in this specification. For these Unicode values, and
46、 for control characters for which there is no defined graphical behaviour, the terminal shall not display any result: neither a glyph is shown nor is the current rendering position changed. 5.4 Font Support Fonts are specified in this specification by name, size, and style. There are three special n
47、ames which shall be recognized by the terminal: Serif, Sans-Serif, and Monospace. It is strongly recommended that these be different fonts for the required characters from ASCII and Latin-1. For many other characters, the terminal may have a limited set or only a single font. Terminals requested to
48、render a character where the selected font does not support that character should substitute a suitable font. This ensures that languages with only one font (e.g. Asian languages) or symbols for which there is only one form are rendered. Fonts are requested by name, in an ordered list. Authors shoul
49、d normally specify one of the special names last in the list. Terminals shall support a pixel size of 12 (on a 72dpi display, this would be a point size of 12). If a size is requested other than the size(s) supported by the terminal, the next smaller supported size should be used. If the requested size is smaller than the smallest supported size, the terminal should use the smallest supported size. Terminals shall support unstyled text for those characters it supports. It may also support bold, italic (oblique) and
