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ETSI TS 102 366 V1.3.1 (2014-08) TECHNICAL SPECIFICATION Digital Audio Compression (AC-3, Enhanced AC-3) Standard 2 ETSI TS 102 366 V1.3.1 (2014-08) Reference RTS/JTC-026 Keywords audio, broadcasting, coding, digital 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 à but non lucratif enregistrée à la Sous-Préfecture de Grasse (06) N° 7803/88 Important notice The present document can be downloaded from: http://www.etsi.org 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 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 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 to one of the following services: http://portal.etsi.org/chaircor/ETSI_support.asp 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 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 2014. © European Broadcasting Union 2014. All rights reserved. DECTTM, PLUGTESTSTM, UMTSTM and the ETSI logo are Trade 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 3 ETSI TS 102 366 V1.3.1 (2014-08) Contents Intellectual Property Rights .............................................................................................................................. 15 Foreword ........................................................................................................................................................... 15 Modal verbs terminology .................................................................................................................................. 15 Introduction ...................................................................................................................................................... 15 1 Scope ...................................................................................................................................................... 19 2 References .............................................................................................................................................. 19 2.1 Normative references ....................................................................................................................................... 19 2.2 Informative references ...................................................................................................................................... 19 3 Definitions and abbreviations ................................................................................................................. 20 3.1 Definitions ........................................................................................................................................................ 20 3.2 Abbreviations ................................................................................................................................................... 21 4 Bit stream syntax .................................................................................................................................... 24 4.1 Synchronization frame ..................................................................................................................................... 24 4.2 Semantics of syntax specification..................................................................................................................... 25 4.3 Syntax specification ......................................................................................................................................... 25 4.3.1 syncinfo - Synchronization information ..................................................................................................... 25 4.3.2 bsi - Bit stream information ........................................................................................................................ 26 4.3.3 audblk - Audio block .................................................................................................................................. 27 4.3.4 auxdata - Auxiliary data .............................................................................................................................. 30 4.3.5 errorcheck - Error detection code ............................................................................................................... 30 4.4 Description of bit stream elements ................................................................................................................... 30 4.4.1 syncinfo - Synchronization information ..................................................................................................... 30 4.4.1.1 syncword - Synchronization word - 16 bits ........................................................................................... 30 4.4.1.2 crc1 - Cyclic redundancy check 1 bit to 16 bits .................................................................................... 30 4.4.1.3 fscod - Sample rate code - 2 bits ........................................................................................................... 30 4.4.1.4 frmsizecod - Frame size code - 6 bits .................................................................................................... 31 4.4.2 bsi - Bit stream information ........................................................................................................................ 31 4.4.2.1 bsid - Bit stream identification - 5 bits .................................................................................................. 31 4.4.2.2 bsmod - Bit stream mode - 3 bits .......................................................................................................... 31 4.4.2.3 acmod - Audio coding mode - 3 bits ..................................................................................................... 31 4.4.2.4 cmixlev - Centre mix level - 2 bits ........................................................................................................ 32 4.4.2.5 surmixlev - Surround mix level - 2 bits ................................................................................................. 32 4.4.2.6 dsurmod - Dolby® Surround mode - 2 bits ........................................................................................... 32 4.4.2.7 lfeon - Low frequency effects channel on - 1 bit ................................................................................... 33 4.4.2.8 dialnorm - Dialogue normalization - 5 bits ........................................................................................... 33 4.4.2.9 compre - Compression gain word exists - 1 bit ..................................................................................... 33 4.4.2.10 compr - Compression gain word - 8 bits ............................................................................................... 33 4.4.2.11 langcode - Language code exists - 1 bit ................................................................................................ 33 4.4.2.12 langcod - Language code - 8 bits .......................................................................................................... 33 4.4.2.13 audprodie - Audio production information exists - 1 bit ....................................................................... 33 4.4.2.14 mixlevel - Mixing level - 5 bits ............................................................................................................. 33 4.4.2.15 roomtyp - Room type - 2 bits ................................................................................................................ 34 4.4.2.16 dialnorm2 - Dialogue normalization, Ch2 - 5 bits ................................................................................. 34 4.4.2.17 compr2e - Compression gain word exists, Ch2 - 1 bit .......................................................................... 34 4.4.2.18 compr2 - Compression gain word, Ch2 - 8 bits..................................................................................... 34 4.4.2.19 langcod2e - Language code exists, Ch2 - 1 bit ...................................................................................... 34 4.4.2.20 langcod2 - Language code, Ch2 - 8 bits ................................................................................................ 34 4.4.2.21 audprodi2e - Audio production information exists, Ch2 - 1 bit ...........................................................
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