1、BRITISH STANDARDBS EN 61937-6:2006Digital audio Interface for non-linear PCM encoded audio bitstreams applying IEC 60958 Part 6: Non-linear PCM bitstreams according to the MPEG-2 AAC and MPEG-4 AAC audio formatsThe European Standard EN 61937-6:2006 has the status of a British StandardICS 33.160.60;
2、35.040g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58Licensed Copy: Wang Bin, na, Fri Dec 15 06:50:54 GMT+00:00 2006, Uncontrolled Copy, (c) BSIBS
3、EN 61937-6:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 October 2006 BSI 2006ISBN 0 580 49327 XNational forewordThis British Standard was published by BSI. It is the UK implementation of EN 61937-6:2006. It is identical with IEC 619
4、37-6:2006. It supersedes BS EN 61937-6:2002 which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee EPL/100, Audio, video and multimedia systems and equipment.A list of organizations represented on EPL/100 can be obtained on request to its secretary.This publi
5、cation does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.Amendments issued since publicationAmd. No. Date CommentsLicensed Copy: Wang Bin, na, Fri
6、Dec 15 06:50:54 GMT+00:00 2006, Uncontrolled Copy, (c) BSIEUROPEAN STANDARD EN 61937-6 NORME EUROPENNE EUROPISCHE NORM July 2006 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Se
7、cretariat: rue de Stassart 35, B - 1050 Brussels 2006 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 61937-6:2006 E ICS 33.160.60, 35.040 Supersedes EN 61937-6:2002English version Digital audio Interface for non-linear PCM encode
8、d audio bitstreams applying IEC 60958 Part 6: Non-linear PCM bitstreams according to the MPEG-2 AAC and MPEG-4 AAC audio formats (IEC 61937-6:2006) Audionumrique Interface pour les flux de bits audio codage MIC non linaire, conformment la CEI 60958 Partie 6: Flux de bits MIC non linaire selon les fo
9、rmats MPEG-2 AAC et MPEG-4 AAC (CEI 61937-6:2006) Digitalton Schnittstelle fr nichtlinear-PCM-codierte Audio-Bitstrme unter Verwendung von IEC 60958 Teil 6: Nichtlineare PCM-Bitstrme nach MPEG-2 AAC- und MPEG-4 AAC-Audio-Formaten (IEC 61937-6:2006) This European Standard was approved by CENELEC on 2
10、006-07-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions 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 b
11、e obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in two official versions (English and 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 Centr
12、al Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the N
13、etherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Licensed Copy: Wang Bin, na, Fri Dec 15 06:50:54 GMT+00:00 2006, Uncontrolled Copy, (c) BSIForeword The text of the International Standard IEC 61937-6:2006, prepared by IEC TC 100, A
14、udio, video and multimedia systems and equipment, was submitted to the formal vote and was approved by CENELEC as EN 61937-6 on 2006-07-01 without any modification. This European Standard supersedes EN 61937-6:2002. It includes the following significant technical changes with respect to EN 61937-6:2
15、002: a) addition of data-type for MPEG2 AAC low sampling frequency; b) additon of data-type for MPEG-4 AAC. The following dates were 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) 2007-07-01 latest d
16、ate by which the national standards conflicting with the EN have to be withdrawn (dow) 2009-07-01 Annex ZA has been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 61937-6:2006 was approved by CENELEC as a European Standard without any modification. _ EN 61937-6:200
17、6 2 Licensed Copy: Wang Bin, na, Fri Dec 15 06:50:54 GMT+00:00 2006, Uncontrolled Copy, (c) BSICONTENTS FOREWORD.4 1 Scope.6 2 Normative references .6 3 Terms, definitions, abbreviations and presentation convention 6 3.1 Terms and definitions .6 3.2 Abbreviations 7 3.3 Presentation convention 7 4 Ma
18、pping of the audio bitstream on to IEC 61937 7 4.1 MPEG-2 AAC burst-info.7 4.2 MPEG-4 AAC burst-info.8 5 Format of MPEG-2 AAC and MPEG-4 AAC data-bursts 8 5.1 Pause data-burst.9 5.2 Audio data-bursts 9 Figure 1 MPEG-2 AAC data-burst 9 Figure 2 Latency of MPEG-2 AAC decoding.10 Figure 3 MPEG-2 AAC ha
19、lf-rate low sampling frequency data-burst .11 Figure 4 Latency of MPEG-2 AAC half-rate low sampling frequency decoding12 Figure 5 MPEG-2 AAC quarter-rate low sampling frequency data-burst13 Figure 6 Latency of MPEG-2 AAC quarter-rate low sampling frequency decoding 14 Figure 7 MPEG-4 AAC data-burst
20、15 Figure 7 Latency of MPEG-4 AAC decoding.16 Figure 8 MPEG-4 AAC half-rate low sampling frequency data-burst .16 Figure 9 Latency of MPEG-4 AAC half-rate low sampling frequency decoding17 Figure 10 MPEG-4 AAC quarter-rate low sampling frequency data-burst18 Figure 11 Latency of MPEG-4 AAC quarter-r
21、ate low sampling frequency decoding 19 Figure 12 MPEG-4 AAC double-rate high sampling frequency data-burst .20 Figure 13 Latency of MPEG-4 AAC double-rate high sampling frequency decoding21 Table 1 Fields of burst-info (data-type=7) 7 Table 2 Fields of burst-info (data-type=19).8 Table 3 Fields of b
22、urst-info (data-type=20).8 Table 4 Repetition period of pause data-bursts 9 Table 5 Repetition period of pause data-bursts 9 Table 6 Data-type-dependent information for data-type MPEG-2 AAC10 Table 7 Data-type-dependent information for data-type MPEG-2 AAC half-rate low sampling frequency.11 Table 8
23、 Data-type-dependent information for data-type MPEG-2 AAC quarter-rate low sampling frequency .13 EN 61937-6:2006 3 Licensed Copy: Wang Bin, na, Fri Dec 15 06:50:54 GMT+00:00 2006, Uncontrolled Copy, (c) BSITable 9 Data-type-dependent information for data-type MPEG-4 AAC15 Table 10 Data-type-depende
24、nt information for data-type MPEG-4 AAC half-rate low sampling frequency.17 Table 11 Data-type-dependent information for data-type MPEG-4 AAC quarter-rate low sampling frequency .18 Table 12 Data-type-dependent information for data-type MPEG-4 AAC double-rate high sampling frequency 20 EN 61937-6:20
25、06 4 Licensed Copy: Wang Bin, na, Fri Dec 15 06:50:54 GMT+00:00 2006, Uncontrolled Copy, (c) BSI 5 DIGITAL AUDIO INTERFACE FOR NON-LINEAR PCM ENCODED AUDIO BITSTREAMS APPLYING IEC 60958 Part 6: Non-linear PCM bitstreams according to the MPEG-2 AAC and MPEG-4 AAC formats 1 Scope This part of IEC 6193
26、7 specifies the method for IEC 60958 to convey non-linear PCM bitstreams encoded in accordance with the MPEG-2 AAC (Advanced Audio Coding) and MPEG-4 AAC formats. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, o
27、nly the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60958 (all parts), Digital audio interface IEC 61937 (all parts), Digital audio Interface for non-linear PCM encoded audio bitstreams applying IEC 60958 IEC 61
28、937-1, 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 IEC 60958 Part 2: Burst-info ISO/IEC 13818-7:2004, Information technology Generic coding of moving p
29、ictures and associated audio information Part 7: Advanced Audio Coding (AAC) ISO/IEC 14496-3:2001, Information technology Coding of audio-visual objects Part 3: Audio Amendment 1 (2003) 3 Terms, definitions, abbreviations and presentation convention For the purposes of this document, the following t
30、erms, definitions, abbreviations and presentation convention apply. 3.1 Terms and definitions 3.1.1 subdata-type reference to the type of payload of the data-burst defined for use with the specified data-type 3.1.2 LC profile low complexity profile identified in ISO/IEC 13818-7 EN 61937-6:2006Licens
31、ed Copy: Wang Bin, na, Fri Dec 15 06:50:54 GMT+00:00 2006, Uncontrolled Copy, (c) BSI3.1.3 LC profile with SBR low complexity profile with spectral band replication identified in ISO/IEC 13818-7 3.1.4 latency delay time of an external audio decoder to decode a MPEG-2 AAC or MPEG-4 AAC data-burst def
32、ined as the sum of two values of the receiving delay time and the decoding delay time 3.1.5 AAC profile AAC profile identified in ISO/IEC 14496-3 3.1.6 HE-AAC profile HE-AAC profile identified in ISO/IEC 14496-3 3.2 Abbreviations AAC Advanced Audio Coding ADTS Audio Data Transport Stream SBR Spectra
33、l Band Replication HE-AAC High Efficiency AAC 3.3 Presentation convention 012Value “01” in binary format 4 Mapping of the audio bitstream on to IEC 61937 The coding of the bitstream and data-burst is in accordance with IEC 61937. 4.1 MPEG-2 AAC burst-info MPEG-2 AAC burst-info (data-type=7) is given
34、 in Table 1. Table 1 Fields of burst-info (data-type=7) Bits of Pc Value Contents Reference point R Repetition period of data-burst in IEC 60958 frames 0-4 Data-type 7 MPEG-2 AAC ADTS Bit 0 of Pa 1 024 5,6 002Reserved 7-15 In accordance with IEC 61937-1 and IEC 61937-2 MPEG-2 AAC burst-info (data-ty
35、pe=19) is given in Table 2. EN 61937-6:2006 6 Licensed Copy: Wang Bin, na, Fri Dec 15 06:50:54 GMT+00:00 2006, Uncontrolled Copy, (c) BSITable 2 Fields of burst-info (data-type=19) Bits of Pc Value Contents Reference point R Repetition period of data-burst in IEC 60958 frames 0-4 Data-type 19 MPEG-2
36、 AAC ADTS low sampling frequency Depends on subdata-type 5,6 Subdata-type 002Subdata-type for MPEG-2 AAC ADTS half- rate low sampling frequency Bit 0 of Pa 2 048 012Subdata-type for MPEG-2 AAC ADTS quarter-rate low sampling frequency Bit 0 of Pa 4 096 102,112Reserved 7-15 In accordance with IEC 6193
37、7-1 and IEC 61937-2 4.2 MPEG-4 AAC burst-info MPEG-4 AAC burst-info (data-type=20) is given in Table 3. Table 3 Fields of burst-info (data-type=20) Bits of Pc Value Contents Reference point R Repetition period of data-burst in IEC 60958 frames 0-4 Data-type 20 MPEG-4 AAC Depends on subdata-type 5,6
38、Subdata-type 002Subdata-type for MPEG4 AAC Bit 0 of Pa 1024 012Subdata-type for MPEG4 AAC half-rate low sampling frequency Bit 0 of Pa 2 048 102Subdata-type for MPEG4 AAC quarter-rate low sampling frequency Bit 0 of Pa 4 096 112Subdata-type for MPEG4 AAC double-rate high sampling frequency Bit 0 of
39、Pa 512 7-15 In accordance with IEC 61937-1 and IEC 61937-2 5 Format of MPEG-2 AAC and MPEG-4 AAC data-bursts This clause specifies the audio data-bursts MPEG-2 AAC and MPEG-4 AAC. Specific properties such as reference points, repetition period, the method of filling stream gaps, and decoding latency
40、 are specified for each data-type. The decoding latency (or delay), indicated for the data-types, should be used by the transmitter to schedule data-bursts as necessary to establish synchronization between the picture and the decoded audio. EN 61937-6:2006 7 Licensed Copy: Wang Bin, na, Fri Dec 15 0
41、6:50:54 GMT+00:00 2006, Uncontrolled Copy, (c) BSI5.1 Pause data-burst 5.1.1 The data MPEG-2 AAC The pause data-burst for MPEG-2 AAC is given in Table 4. Table 4 Repetition period of pause data-bursts Repetition period of pause data-burst Data-type of audio data-burst Mandatory Recommended MPEG-2 AA
42、C MPEG-2 AAC and half-rate low sampling frequency MPEG-2 AAC and quarter-rate low sampling frequency - - - 32 IEC 60958 frames 64 IEC 60958 frames 128 IEC 60958 frames 5.1.2 The data MPEG-4 AAC The pause data-burst for MPEG-4 AAC is given in Table 5. Table 5 Repetition period of pause data-bursts Re
43、petition period of pause data-burst Data-type of audio data-burst Mandatory Recommended MPEG-4 AAC MPEG-4 AAC and half-rate low sampling frequency MPEG-4 AAC and quarter-rate low sampling frequency MPEG-4 AAC double-rate high sampling frequency - - - - 32 IEC 60958 frames 64 IEC 60958 frames 128 IEC
44、 60958 frames 16 IEC 60958 frames 5.2 Audio data-bursts 5.2.1 The data MPEG-2 AAC The stream of the data-bursts for MPEG-2 AAC consists of sequences of MPEG-2 AAC ADTS frames. The data-type of an MPEG-2 AAC data-burst is 7. The data-burst is headed with a burst-preamble, followed by the burst-payloa
45、d, and stuffed with stuffing bits. The burst-payload of each data-burst of MPEG-2 AAC data shall contain one complete MPEG-2 AAC ADTS frame and represents 1 024 samples for each encoded channel. The length of the MPEG-2 AAC data-burst depends on the encoded bit rate (which determines the MPEG-2 AAC
46、ADTS frame length). The reference to the specification for the MPEG-2 AAC bitstream, representing 1 024 samples of encoded audio per frame is found in ISO/IEC 13818-7. Bit 0 of Pa AAC frame MPEG-2 AAC burst_payload Pd Pa Pb Pc AAC frame Repetition period of the burst Stuffing Bit 0 of PaRegular rate
47、 of the MPEG-2 AAC framesMPEG-2 AAC burst_payload Pd Pa Pb Pc Figure 1 MPEG-2 AAC data-burst The data-type-dependent information for MPEG-2 AAC is given in Table 6. EN 61937-6:2006 8 Licensed Copy: Wang Bin, na, Fri Dec 15 06:50:54 GMT+00:00 2006, Uncontrolled Copy, (c) BSITable 6 Data-type-dependen
48、t information for data-type MPEG-2 AAC Bits of Pc LSBMSB Value Contents00 No indication 01 LC profile 02, 03 Reserved for future profile 8-12 04-31 Reserved The reference point of an MPEG-2 AAC data-burst is bit 0 of Pa and occurs exactly once every 1 024 sampling periods. The data-burst containing
49、MPEG-2 AAC frames shall occur at a regular rate, with the reference point of each MPEG-2 AAC data-burst beginning 1 024 IEC 60958 frames after the reference point of the preceding MPEG-2 AAC data-burst (of the same bitstream number). It is recommended that pause data-bursts are used to fill stream gaps in the MPEG-2 AAC bit- stream as described in IEC 61937, and that pause data-bursts be transmitted with a repetition period of
