1、BRITISH STANDARDBS EN 61937-7:2005Digital audio Interface for non-linear PCM encoded audio bitstreams applying IEC 60958 Part 7: Non-linear PCM bitstreams according to the ATRAC, ATRAC2/3 and ATRAC-X formats ICS 33.160.01g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g4
2、4g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58+A1:2016(IEC 61937-7:2004)BS EN 61937-7:2005+A1:2016This British Standard was published under the authority of the Standards Policy and Strategy Committee on 25 January 2006ISBN 9
3、78 0 580 91329 7National forewordThis British Standard is the UK implementation of EN 61937-7:2005+A1:2016. It is identical to IEC 61937-7:2004, incorporating amendment 1:2016. It supersedes BS EN 61937-7:2005 which is withdrawn.The UK participation in its preparation was entrusted to Technical Comm
4、ittee EPL/100, Audio, video and multimedia systems and equipment.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct applicatio
5、n.Compliance with a British Standard cannot confer immunity from legal obligations.Amendments/corrigenda issued since publication The British StandardsInstitution 2016. Published byBSI Standards Limited 2016Date Comments 31 October 2016 Implementation of IEC amendment 1:2016 with CENELEC endorsement
6、 A1:2016 The start and finish of text introduced or altered by amendment is indicated in the text by tags. Tags indicating changes to IEC text carry the number of the IEC amendment. For example, text altered by IEC amendment 1 is indicated by .!“EUROPEAN STANDARD EN 61937-7NORME EUROPENNE EUROPISCHE
7、 NORM September 2016 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2005 CENELEC - All rights of exploitation in any form and b
8、y any means reserved worldwide for CENELEC members. Ref. No. EN 61937-7:2005 E ICS 33.160.01 English version Digital audio - Interface for non-linear PCM encoded audio bitstreams applying IEC 60958 Part 7: Non-linear PCM bitstreams according to the ATRAC, ATRAC2/3 and ATRAC-X formats (IEC 61937-7:20
9、04) Audionumrique - Interface pour les flux de bits audio codage MIC (PCM) non linaire conformment la CEI 60958 Partie 7 : Flux de bits MIC (PCM) non-linaire selon les formats ATRAC, 2/3 ATRAC et X-ATRAC (CEI 61937-7:2004) Digitalton - Schnittstelle fr nichtlinear-PCM-codierte Audio-Bitstrme unter V
10、erwendung von IEC 60958 Teil 7: Nichtlineare PCM-Bitstrme entsprechend ATRAC-, ATRAC2/3- und ATRAC-X-Formaten (IEC 61937-7:2004) This European Standard was approved by CENELEC on 2005-07-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions
11、for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three of
12、ficial versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical co
13、mmittees of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. :2005+A1 Forewor
14、d The text of the International Standard IEC 61937-7:2004, prepared by Technical Area 4, Digital submitted to the formal vote and was approved by CENELEC as EN 61937-7 on 2005-07-01 withoutany modification. This European Standard supersedes EN 61937-7:2002. It includes the following significant tech
15、nical changes with respect to EN 61937-7:2002: a) a new audio data-type “ATRAC-X“ is added to ATRAC and ATRAC2/3; b) specific properties such as reference points, repetition period, the method of filling stream gaps, and decoding latency are specified for the data-type ATRAC-X. The following dates w
16、ere fixed: latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2006-07-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2008-07-01 Annex ZA has been added by CENE
17、LEC. _ Endorsement notice The text of the International Standard IEC 61937-7:2005 was approved by CENELEC as a European Standard without any modification. In the official version, for Bibliography, the following note has to be added for the standard indicated: IEC 61909 NOTE Harmonized as EN 61909:2
18、000 (not modified). _ EN 61937-7:2005 2 interfaces and protocols, of IEC TC 100, Audio, video and multimedia systems and equipment, wasForeword to amendment A1 The text of document 100/2503/CDV, future IEC 61937-7:2005/A1, prepared by IEC/TC 100, “Audio, video and multimedia systems and equipment“ w
19、as submitted to the IEC-CENELEC parallel vote and approved by CENELEC as EN 61937-7:2005/A1:2016. The following dates are fixed: latest date by which the document has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2017-03-17 latest date b
20、y which the national standards conflicting with the document have to be withdrawn (dow) 2019-06-17 Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CENELEC and/or CEN shall not be held responsible for identifying any or all such pa
21、tent rights. Endorsement notice The text of the International Standard IEC 61937-7:2005/A1:2016 was approved by CENELEC as a European Standard without any modification.+A1:2016 BS EN 61937-7:2005+A1:2016Annex ZA (normative) Normative references to international publications with their corresponding
22、European publications The following referenced documents are indispensable for the application of this document. For da ted references, only the edition cited applies. For undated references, the latest edition of the referenc ed document (including any amendments) applies. NOTE Where an internation
23、al publication has been modified by common modifications, indicated by (mod), the relevan t EN/HD applies. Publication Year Title EN/HD Year IEC 60958-1 - 1)Digital audio interface Part 1: General EN 60958-1 2004 2)IEC 60958-3 - 1)Part 3: Consumer applications EN 60958-3 2003 2)IEC 61937-1 - 1)Digit
24、al audio - Interface for non-linear PCM encoded audio bitstreams applying IEC 60958 Part 1: General EN 61937-1 2003 2)IEC 61937-2 - 1)Part 2: Burst-info EN 61937-2 2003 2)1)Undated reference. 2)Valid edition at date of issue. 3 BS EN 61937-7:2005+A1:2016EN 61937-7:2005+A1:2016 4 CONTENTS 1 Scope 5 2
25、 Normative references .5 3 Terms, definitions and abbreviations .5 3.1 Definitions .5 3.2 Abbreviations 5 4 Mapping of the audio bitstream on to IEC 61937 .6 4.1 General .6 4.2 ATRAC, ATRAC2/3 and ATRAC-X burst-info 6 5 Format of ATRAC, ATRAC2/3 and ATRAC-X data-bursts.6 5.1 General .6 5.2 Audio dat
26、a-bursts 7 5.2.1 The data ATRAC7 5.2.2 Latency of ATRAC decoding.8 5.2.3 The data ATRAC2/3 .8 5.2.4 Latency of ATRAC2/3 decoding9 5.2.5 The data ATRAC-X 10 5.2.6 Latency of ATRAC-X decoding .11 Bibliography .13 Annex ZA (normative) Normative references to international publications with their corres
27、ponding European publications 14 Figure 1 ATRAC data-burst 7 Figure 2 Latency of ATRAC decoding.8 Figure 3 ATRAC2/3 data-burst .9 Figure 4 Latency of ATRAC2/3 decoding 10 Figure 5 ATRAC-X data-burst.10Figure 6 Latency of ATRAC-X decoding11 Table 1 Fields of burst-info.6 Table 2 Data-type-dependent i
28、nformation for data-type ATRAC.7 Table 3 Data-type-dependent information for data-type ATRAC2/39 Table 4 Data-type-dependent information for data-type ATRAC-X .11 BS EN 61937-7:2005+A1:2016IEC 61937-7:2004+A1:2016 5 DIGITAL AUDIO INTERFACE FOR NON-LINEAR PCM ENCODED AUDIO BITSTREAMS APPLYING IEC 609
29、58 Part 7: Non-linear PCM bitstreams according to the ATRAC, ATRAC2/3 and ATRAC-X formats 1 Scope This part of IEC 61937 specifies the method for the digital audio interface specified in IEC 60958 to convey non-linear PCM bitstreams encoded in accordance with the ATRAC, ATRAC2/3 and ATRAC-X formats.
30、 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60958-1, Digital audi
31、o interface Part 1: General IEC 60958-3, Digital audio interface Part 3: Consumer applications IEC 61937-1, Digital audio Interface for non-linear PCM encoded audio bitstreams applying IEC 60958 Part 1: General IEC 61937-2, Digital audio Interface for non-linear PCM encoded audio bitstreams applying
32、 IEC 60958 Part 2: Burst-info 3 Terms, definitions and abbreviations 3.1 Definitions For the purposes of this document, the definitions given in IEC 61937-1 and IEC 61937-2, as well as the following, apply. 3.1.1 latency delay time of an external audio decoder to decode an ATRAC, ATRAC2/3 and ATRAC-
33、X data-burst, defined as the sum of two values of the receiving delay time and the decoding delay time 3.2 Abbreviations ATRAC Adaptive TRansform Acoustic Coding ATRAC2 Adaptive TRansform Acoustic Coding 2 ATRAC3 Adaptive TRansform Acoustic Coding 3 ATRAC2/3 ATRAC2 and/or ATRAC3 ATRAC-X Adaptive TRa
34、nsform Acoustic Coding-X BS EN 61937-7:2005+A1:2016IEC 61937-7:2004+A1:2016 6 4 Mapping of the audio bitstream on to IEC 61937 4.1 General The coding of the bitstream and data-burst shall be in accordance with IEC 61937-1 and IEC 61937-2. 4.2 ATRAC, ATRAC2/3 and ATRAC-X burst-info This 16-bit burst-
35、info shall contain data-burst information structured in accordance with Table 1. Table 1 Fields of burst-info 5 Format of ATRAC, ATRAC2/3 and ATRAC-X data-bursts 5.1 General This clause specifies the audio data-bursts ATRAC, ATRAC2/3 and ATRAC-X. Specific properties such as reference points, repetit
36、ion period, the method of filling stream gaps, and decoding latency are specified for each data-type of ATRAC, ATRAC2/3 and ATRAC-X. The decoding latency (or delay), indicated for the data-types, shall be used by the transmitter to schedule data-bursts as necessary to establish synchronization betwe
37、en the picture and the decoded audio. NOTE For ATRAC, ATRAC2/3 and ATRAC-X formats, the recommended repetition value period of pause data-bursts is 32 IEC 60958 frames. Bits of Pc Value Contents Reference point R Repetition period of data-burst in IEC 60958 frames 0-4 Data-type 0-13 In accordance wi
38、th IEC 61937-1 and IEC 61937-2 14 ATRAC bit 0 of Pa 512 15 ATRAC2/3 bit 0 of Pa 1 024 16 ATRAC-X Subdata-type dependent Subdata-type dependent 17-31 In accordance with IEC 61937-2 5, 6 002Reserved in ATRAC and ATRAC2/3 formats 002Subdata-type for ATRAC-X bit 0 of Pa 2 048 012Subdata-type for ATRAC-X
39、 low latency bit 0 of Pa 512 102Subdata-type for ATRAC-X low latency bit 0 of Pa 256 112Subdata-type for ATRAC-X low latency bit 0 of Pa 128 7-15 In accordance with IEC 61937-1 and IEC 61937-2 !“BS EN 61937-7:2005+A1:2016IEC 61937-7:2004+A1:2016 7 5.2 Audio data-bursts 5.2.1 The data ATRAC The ATRAC
40、 bitstream consists of sequences of ATRAC frames. The data-type of an ATRAC data-burst is 0Eh. The data-burst is headed with a burst-preamble, followed by the burst-payload, and is stuffed with stuffing bits (see Figure 1). The burst-payload of each data-burst of ATRAC data shall contain one complet
41、e ATRAC frame, and represents 512 samples for each encoded channel. The length of the ATRAC data-burst depends on the encoded bit rate (which determines the ATRAC-frame length). NOTE The reference to the specification for the ATRAC bitstream, representing 512 samples of encoded audio per frame, may
42、be found in the bibliography. ATRAC frame Stuffing ATRAC frame Pa Pb Pc Pd ATRAC Burst_payload ATRAC Burst_payload Pa Pb Pc Pd Bit 0 of Pa Bit 0 of Pa Repetition period of the burst Regular rate of ATRAC frames IEC 1525/04Figure 1 ATRAC data-burst The data-type-dependent information for ATRAC is giv
43、en in Table 2. Table 2 Data-type-dependent information for data-type ATRAC Bits of Pc LSBMSB Data type dependent, bit number LSBMSB Contents 8-12 00h 1Fh reserved, shall be set to 0 The reference point of an ATRAC data-burst is bit 0 of Pa and shall occur exactly once every 512 sampling periods. The
44、 data-burst containing ATRAC frames shall occur at a regular rate, with the reference point of each ATRAC data-burst beginning 512 IEC 60958 frames after the reference point of the preceding ATRAC data-burst (of the same bit-stream-number). NOTE 1 It is recommended that Pause data-bursts are used to
45、 fill stream gaps in the ATRAC bit stream as described in IEC 61937-1, and that Pause data-bursts be transmitted with a repetition period of 32 IEC 60958 frames, except when other repetition periods are necessary to fill the precise stream-gap length (which may not be a multiple of 32 IEC 60958 fram
46、es), or to meet the requirement on burst spacing (see IEC 61937-1). When a stream gap in an ATRAC stream is filled by a sequence of Pause data-bursts, the Pa of the first Pause data-burst shall be located 512 sampling periods following the Pa of the previous ATRAC frame. NOTE 2 It is recommended tha
47、t the sequence(s) of Pause data-bursts which fill the stream gap should continue from this point up to (as close as possible considering the 32 IEC 60958 frame length of the Pause data-burst) the Pa of the first ATRAC data-burst which follows the stream gap. The gap-length parameter contained in the
48、 Pause data-burst is intended to be interpreted by the ATRAC decoder as an indication of the number of decoded PCM samples which are missing (due to the resulting audio gap). BS EN 61937-7:2005+A1:2016IEC 61937-7:2004+A1:2016 8 5.2.2 Latency of ATRAC decoding The latency of an external audio decoder
49、 to decode ATRAC is defined as the sum of the receiving delay time and the decoding delay time, as illustrated in Figure 2. ATRAC frame Stuffing ATRAC framePa Pb Pc Pd ATRAC Burst_payload ATRAC Burst_payload Pa Pb Pc Pd Bit 0 of Pa Bit 0 of Pa Repetition period of the burst Receiving delay Decoding delay Latency of ATRAC decoder IEC 1526/04 Figure 2 Latency of ATRAC decoding EXAMPLE The receiving delay time to receive a whole data-burst is calculated as foll
