1、BRITISH STANDARD BS EN 61937-1:2007Digital audio Interface for non-linear PCM encoded audio bitstreams applying IEC 60958 Part 1: GeneralICS 33.160.30nullnull nullnullnullnullnullnullnull nullnullnullnullnullnullnull nullnullnull nullnullnullnullnullnullnullnullnullnull nullnullnullnullnullnull null
2、null nullnullnullnullnullnullnullnullnull nullnull nullnullnullnullnullnullnullnullnull nullnullnull+A1:2011National forewordThis British Standard is the UK implementation of EN 61937-1:2007+A1:2011. It is identical to IEC 61937-1:2007 incorporating amendment 1:2011. It supersedes BS EN 61937-1:2007
3、 which is withdrawn.The start and finish of text introduced or altered by amendment is in-dicated in the text by tags.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 !“.The UK participation in its preparation wa
4、s entrusted to Technical Com-mittee 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 responsi
5、ble for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.BS EN 61937-1:2007+A1:2011This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 May 2007 BSI 2011Amendments/corrigenda issued since
6、publicationDate Comments 31 December 2011 Implementation of IEC amendment 1:2011 with CENELEC endorsement A1:2011.ISBN 978 0 580 76934 4EUROPEAN STANDARD EN 61937-1:2007+A1NORME EUROPENNE EUROPISCHE NORMCENELEC European Committee for Electrotechnical Standardization Comit Europen de NormalisationEle
7、ctrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2007 CENELEC - All rights of exploitation in any formand byanymeans reserved worldwide for CENELEC members. Ref. No. EN 61937-1:2007 E ICS 33.160.30 Supersedes EN 61937-1:2003Eng
8、lish version Digital audio - Interface for non-linear PCM encoded audio bitstreams applying IEC 60958 - Part 1: General (IEC 61937-1:2007)Audionumrique - Interface pour les flux de bits audio codage MIC non linaire conformment la CEI 60958 -Partie 1: Gnralits (CEI 61937-1:2007) Digitalton - Schnitts
9、telle fr nichtlinear-PCM-codierte Audio-Bitstrme unter Verwendung von IEC 60958 -Teil 1: Allgemeines (IEC 61937-1:2007) This European Standard was approved by CENELEC on 2007-02-01. CENELEC members arebound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving
10、 thisEuropean Standard the status ofanational standardwithout anyalteration.Up-to-date lists and bibliographical references concerning suchnational standards may be obtained on application to the Central Secretariat or toanyCENELEC member. This European Standard exists in two official versions (Engl
11、ish and German). A versionin anyother language made by translation under the responsibilityof aCENELEC memberintoits own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Bu
12、lgaria, Cyprus, theCzechRepublic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,Latvia, Lithuania,Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania,Slovakia, Slovenia, Spain,Sweden, Switzerlandand theUnited Kingdom. November 2011 2 Foreword
13、The text of document 100/1101/CDV, future edition 2 of IEC 61937-1, prepared by Technical Area 4,Digital system interfaces and protocols, of IEC TC 100, Audio, video and multimedia systems andequipment, was submitted to the IEC-CENELEC parallel Unique Acceptance Procedure and was approved by CENELEC
14、 as EN 61937-1 on 2007-02-01. This European Standard supersedes EN 61937-1:2003. This edition contains the following significant technical changes with respect to EN 61937-1:2003. The data-type field in Pc is expanded from bit 0-4 to bit 0-6. A new additional definition of Pd is specified. The numbe
15、rs of times for symbol frequency are changed to refer to each part of EN 61937. The requirement for burst spacing is changed. The following dates were fixed: latest date by which the EN has to be implementedat national level by publication of an identical national standard or by endorsement (dop) 20
16、07-11-01 latest date by which the national standards conflictingwith the EN have to be withdrawn (dow) 2010-02-01 Annex ZA has been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 61937-1:2007 was approved by CENELEC as a EuropeanStandard without any modification. _
17、 Foreword to amendment A1 The text of document 100/1810/CDV, future edition 2 of IEC 61937-1:2007/A1, prepared by technical area 4, “Digital system interfaces and protocols“, of IEC TC 100 “Audio, video and multimedia systems and equipment“ was submitted to the IEC-CENELEC parallel vote and approved
18、 by CENELEC as EN 61937-1:2007/A1:2011. 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) 2012-08-16 latest date by which the national standards conflicting with the docume
19、nt have to be withdrawn (dow) 2014-11-16 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 patent rights. Endorsement notice The text of the Internatio
20、nal Standard IEC 61937-1:2007/A1:2011 was approved by CENELEC as a European Standard without any modification. BS EN 61937-1:2007+A1:2011 EN 61937-1:2007+A1:2011 (E) 3 CONTENTS1Scope 52Normative references.53Terms, definitions, abbreviations and presentation53.1 Definitions.53.2 Abbreviations73.3 Pr
21、esentation convention74General description75Interface format86Mapping of the audio bitstream on to IEC 60958.86.1 Coding of the bitstream86.2 Burst-payload136.3 Stuffing.147Format of data-bursts.147.1 Pause data-burst.157.2 Audio data-bursts187.3 Null data-burst.18Annex A (normative) Channel status
22、when IEC 60958 isused in consumerapplications19 Annex ZA (normative) Normative references to international publications withtheircorresponding European publications21Bibliography.20Figure 1 IEC 60958 interface format.8Figure 2 Data-burst format.10Figure 3 Burst-preamble.10Figure 4 Burst-preamble wit
23、h extended preamble .12Figure 5 Length of the burst-payload specified by Pd13Figure 6 Burst spacing.14Figure 7 Flow chart of transmission ofa bitstream15Figure 8 Bridging gaps in-betweendata-bursts with three pause data-bursts.16Figure 9 Data-burst format of the data-type pause17Figure 10 Null data-
24、burst18Table 1 Bit allocation of the IEC 60958 frame.8Table 2 Bit allocation of data-burst in IEC 60958 subframes9Table 3 Burst-preamble words11Table 4 Bit map of burst-preambles11Table 5 Fields of burst-info.11Table 6 Burst-preamble words12Table 7 Fields of Pe (extended data-type)12BS EN 61937-1:20
25、07+A1:2011 EN 61937-1:2007+A1:2011 (E) 4 Table 8 Fields of Pf12Table9 Values of data -type-dependent info ofthe pause data-burst .17Table10 Burst-payload of pause data-burst18Table 11 Fieldsof a null data-burst18Table A.1 Allocation of the channel statusbits19BS EN 61937-1:2007+A1:2011 EN 61937-1:20
26、07+A1:2011 (E) 5 DIGITAL AUDIO INTERFACE FOR NON-LINEAR PCM ENCODED AUDIO BITSTREAMS APPLYING IEC 60958 Part 1: General 1 Scope This part ofIEC 61937 applies to the digital audio interface using the IEC 60958 series for the conveying of non-linear PCM encodedaudio bitstreams. It describes theway inw
27、hich this digital interface canbe used in consumerapplications. The professional mode (AES/EBU) is not considered within the scope of thisstandard. 2 Normative references Thefollowing referenced documents are indispensable for the application of this document. Fordated references, only the edition c
28、itedapplies. For undated references, the latesteditionof the referenced document (includingany amendments) applies. IEC 60958 (all parts), Digital audio interfaceIEC 61937 (all parts), Digital audio Interface for non-linear PCM encoded audio bitstreamsapplying IEC 609583 Terms, definitions, abbrevia
29、tions and presentation For the purposes of this document, the following terms, definitions, abbreviations and presentation convention apply. 3.1 Definitions3.1.1 audio data-burstdata-burst with an encoded audio frame as burst-payload3.1.2 audio data-word16-bit data word3.1.3 audio framefixed number
30、of audio samplesNOTE The number of samples in an audio frame is dependent on the particular encoding system which is used toencode the audio frame into the encoded audio frame. 3.1.4 audio gap period in the sequence of baseband audio samples where valid samples of audio are not availableBS EN 61937-
31、1:2007+A1:2011 EN 61937-1:2007+A1:2011 (E) 6 3.1.5 bitstream non-linear PCM encoded audio source, r epresented in a sequence ofbitsNOTE In this interface the bitstream consists of a sequence of data-bursts. 3.1.6 data-burstpacket of data, including theburst -preamble, to be transmitted across the in
32、terface3.1.7 burst-payload information content of the data-burst3.1.8 burst-preamble header for the data-burst, containing synchronization, and information about the data contained in the burst-payload 3.1.9 data-type reference tothe type of payload of the data-bursts 3.1.10encoded audio frame minim
33、um decodable unit of an encoded data sequenceNOTE Each encoded audio frame is the encoded representation of a fixed number of audio samples (for each original audio channel). The number of samples which are encoded into an encoded audio frame depends on theparticular encoding system which is used to
34、 encode the audio frame into the encoded audio frame. 3.1.11idle state in which the interface is not used to convey any sequence of data-bursts or PCM dataNOTE The channel status data is still active (bit b1 is set to 1 when further non-linear PCM encoded audio isanticipated; see Figure 7). 3.1.12le
35、ngth-codecode indicating the length of the data-burst-payload in bits, bytes or 8-bytes unit3.1.13repetition period period between the reference point of the current data-burst and the referencepoint of the immediately following data-burst of the same data-type3.1.14sampling frequencysampling freque
36、ncy of the encoded PCM audio samples (i.e. before encoding and after decoding) 3.1.15sampling period time period related to the sampling frequency of the PCM audio samples,represented in theencoded bitstream 3.1.16stuffingoccupying the unused data capacity of the interface! “BS EN 61937-1:2007+A1:20
37、11 EN 61937-1:2007+A1:2011 (E) 7 3.1.17stuffing subframeoccupying the unused data capacity in 16-bit audio datawords3.1.18stream gapperiod within the encoded audio bitstream without any audio frame; adiscontinuity in the bitstreamNOTE Typically, a stream gap will occur between encoded audio frames.
38、3.2 Abbreviations 3.2.1 MPEGMoving Pictures Expert Group, ajoint committee of ISO and IEC3.2.2 SMPTE The Society of Motion Picture and Television Engineers 3.2.3 ETSI European Telecommunication Standards Institute3.2.4 ATSCAdvanced TelevisionStandards Committee3.3 Presentation conventionF872h Value
39、F872 in hexadecimal format 4 General description The formatof the IEC 60958 interface consists of a sequence of IEC 60958 subframes. Each IEC 60958 subframe is normally used to carry one linear PCM sample but may also be usedto convey data. The non-linear PCM encoded audio bitstreams to be transport
40、ed over this interfaceare formed into a sequence ofdata-bursts.Eachdata-burst consists of a 64-bit burst-preamble, followed by the burst-payload. The burst-preambleconsists of a sync-word, information about the burst-payload and a bitstream number. The interface may convey one or more bitstreams. Ea
41、ch type of bitstream may impose aparticularrequirement for the repetition period for the data-bursts that make up the bitstream (see Clause 7). The 16 bits of a data-burst are placedin time-slots 12-27 ofanIEC 60958 subframe. Both odd and even IEC 60958 subframes (ch1, ch2) are simultaneously used t
42、o carry 32 bits of data. This allows IEC 60958, in the consumer mode, to convey either two-channel linearPCM audio, or a set of non-linear PCM encoded bitstreams (alternating data words), but not bothsimultaneously. BS EN 61937-1:2007+A1:2011 EN 61937-1:2007+A1:2011 (E) 8 5 Interface format The inte
43、rface formatasdefined in IEC 60958-1 and IEC 60958-3 is used. 6Mappingof the audio bitstream on toIEC 609586.1 Coding of the bitstreamThe non-linear PCM encoded audio bitstream is transferred using the basic 16-bit data area of the IEC 60958 subframes,i.e. in time-slots 12 to 27. Because the non-lin
44、ear PCM encodedaudio bitstream to betransported is at alower data rate than that supported by the IEC 60958 interface, the audio bitstream is broken into a sequence ofdiscrete data-bursts, and stuffing between the data-bursts is necessary (see6.3). Each data-burst contains data of an encoded audio f
45、rame that is the encoded representationof a fixed number of audio samples per PCM audio channel. The number of samples to beencoded into an encoded audio frame depends on the particular encoding system. It is possible for this interface to simultaneously convey multiple non-linear PCM encoded audio
46、bitstreams. One of the applications of this capability would be to convey botha mainaudio service and an associated audio service. W B W MFrame 0 Frame 0Frame 191 Frame 1 Frame 1911 block = 192 framesPreamble Auxiliary LSB MSB V U C P0 3 4 7 8 11 12 27 28 3116-bit of bitstreamIEC 1288/03Figure 1 IEC
47、 60958 interface formatTable 1 Bit allocation of the IEC 60958 frameField IEC 60958 time-slot Value 0 3 Preamble IEC 60958 preamble 4 7 Auxiliary field Not used, all “0” 8 11 Unused data bits Not used, all “0” 12 27 16-bit data Sections of the bitstream 28 Validity flag According to IEC 60958 29 Use
48、r data According to IEC 60958 30 Channel status According to IEC 60958 31 Parity bit According to IEC 60958 BS EN 61937-1:2007+A1:2011 EN 61937-1:2007+A1:2011 (E) 9 6.1.1Bit map of bitstream Themethod of placing the data into the IEC60958 bitstream is to format the data tobetransmittedinto data-burs
49、ts and to send each d ata-burst in a continuous sequence of IEC 60958 frames. Table 2 Bit allocation of data-burst in IEC 60958 subframes Bit of subframes Subframe MSB b27 b26 b25 b14 b13 LSB b12 Frame 0; subframe B or M 0 1 14 15 Frame 0; subframe W 16 17 30 31 Frame 1; subframe B or M 32 33 46 47 Frame 1; subframe W 48 49 62 63 Frame 2; subframe B or M 64 65 78 79 - - Last subframe B or M of data-burst n-32
