1、Audio archive system Part 2: Audio data preservation PD IEC/TS 62702-2:2016 BSI Standards Publication WB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06National foreword This Published Document is the UK implementation of IEC/TS 62702-2:2016. The UK participation in its preparation was entrust
2、ed to Technical Committee 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
3、its correct application. The British Standards Institution 2016. Published by BSI Standards Limited 2016 ISBN 978 0 580 86235 9 ICS 33.160.30; 35.220.30 Compliance with a British Standard cannot confer immunity from legal obligations. This Published Document was published under the authority of the
4、Standards Policy and Strategy Committee on 30 June 2016. Amendments/corrigenda issued since publication Date Text affected PUBLISHED DOCUMENT PD IEC/TS 62702-2:2016 IEC TS 62702-2 Edition 1.0 2016-05 TECHNICAL SPECIFICATION Audio archive system Part 2: Audio data preservation INTERNATIONAL ELECTROTE
5、CHNICAL COMMISSION ICS 33.160.30; 35.220.30 ISBN 978-2-8322-3286-6 Registered trademark of the International Electrotechnical Commission Warning! Make sure that you obtained this publication from an authorized distributor. PD IEC/TS 62702-2:2016 2 IEC TS 62702-2:2016 IEC 2016 CONTENTS FOREWORD . 3 I
6、NTRODUCTION . 5 1 Scope 6 2 Normative references. 6 3 Terms and definitions 6 4 Objective media inspection 6 4.1 Criteria of the objective media . 6 4.2 Criteria of the archival media for preservation and dissemination . 7 5 Digitization of audio content . 7 5.1 Condition and environment 7 5.2 Digit
7、ization method . 7 5.2.1 Content of analogue media . 7 5.2.2 Content of digital media . 8 6 Inspection of digitised file and recorded media . 9 7 Reception of digitised content 10 8 Archival information package . 10 8.1 Content information . 10 8.2 Package format for AIP . 10 9 Preservation 11 10 Ac
8、cess 11 11 Dissemination 11 11.1 Format 11 11.2 Copyright management . 12 Annex A (informative) Digital signal capturing . 13 Annex B (informative) Digitised content inspection in disk media . 15 Annex C (informative) Treatment of content noise. 16 Bibliography . 17 Figure 1 Digitization of analogue
9、 signals 7 Figure 2 Digital signal capturing . 9 Figure A.1 Signal capturing from the D/A converter signal . 13 Figure A.2 Signal capturing from the digital audio interface . 14 Table 1 Digital signal format . 8 Table 2 File format . 8 Table 3 Digital to digital conversion format . 9 Table 4 Audio f
10、ile format 9 Table 5 Content information . 10 Table 6 Dissemination format . 11 PD IEC/TS 62702-2:2016IEC TS 62702-2:2016 IEC 2016 3 INTERNATIONAL ELECTROTECHNICAL COMMISSION _ AUDIO ARCHIVE SYSTEM Part 2: Audio data preservation FOREWORD 1) The International Electrotechnical Commission (IEC) is a w
11、orldwide organization for standardization comprising all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and in addition to othe
12、r activities, IEC publishes International Standards, Technical Specifications, Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested in the s
13、ubject dealt with may participate in this preparatory work. International, governmental and non- governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions
14、 determined by agreement between the two organizations. 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international consensus of opinion on the relevant subjects since each technical committee has representation from all interested IEC National
15、Committees. 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC Publications is accurate, IEC cannot be held responsible for the way in
16、which they are used or for any misinterpretation by any end user. 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications transparently to the maximum extent possible in their national and regional publications. Any divergence between any IEC Publ
17、ication and the corresponding national or regional publication shall be clearly indicated in the latter. 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity assessment services and, in some areas, access to IEC marks of conformity. IEC is
18、 not responsible for any services carried out by independent certification bodies. 6) All users should ensure that they have the latest edition of this publication. 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and members of its tec
19、hnical committees and IEC National Committees for any personal injury, property damage or other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IE
20、C Publications. 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is indispensable for the correct application of this publication. 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subj
21、ect of patent rights. IEC shall not be held responsible for identifying any or all such patent rights. The main task of IEC technical committees is to prepare International Standards. In exceptional circumstances, a technical committee may propose the publication of a technical specification when th
22、e required support cannot be obtained for the publication of an International Standard, despite repeated efforts, or the subject is still under technical development or where, for any other reason, there is the future but no immediate possibility of an agreement on an International Standard. Technic
23、al specifications are subject to review within three years of publication to decide whether they can be transformed into International Standards. IEC 62702-2, which is a technical specification, has been prepared by technical area 6: Storage media, storage data structures, storage systems and equipm
24、ent, of IEC technical committee 100: Audio, video and multimedia systems and equipment. PD IEC/TS 62702-2:2016 4 IEC TS 62702-2:2016 IEC 2016 The text of this technical specification is based on the following documents: Enquiry draft Report on voting 100/2461/DTS 100/2519/RVC Full information on the
25、 voting for the approval of this technical specification can be found in the report on voting indicated in the above table. A list of all parts in the IEC 62702 series, published under the general title Audio archive system, can be found on the IEC website. This publication has been drafted in accor
26、dance with the ISO/IEC Directives, Part 2. The committee has decided that the contents of this publication will remain unchanged until the stability date indicated on the IEC website under “http:/webstore.iec.ch“ in the data related to the specific publication. At this date, the publication will be
27、transformed into an International standard, reconfirmed, withdrawn, replaced by a revised edition, or amended. A bilingual version of this publication may be issued at a later date. PD IEC/TS 62702-2:2016IEC TS 62702-2:2016 IEC 2016 5 INTRODUCTION Sound recordings such as music, speech, and storytel
28、ling are an important human heritage and should be preserved whenever possible. However, we were unable to record and preserve sounds until Edison achieved the first recording in 1877. Although various technologies were invented later, most of them have a limited lifespan with respect to audio archi
29、ving because storage and sound quality deteriorates when it is transferred to the next generation storage device. The progress of LSI technology made it possible to digitize recorded sound. The digital recording is very suitable for audio archiving because the migration is performed by copying digit
30、al data. There can be various recording materials for this purpose, they are optical disks, magnetic disks, magnetic tape and non-volatile memories such as phase change memory. This Technical Specification specifies physical and logical aspects for a standard of audio archives of various storage typ
31、es which are typically used for audio archives in markets. The IEC 62702 series currently consists of: Part 1 which specifies the minimum requirements on physical aspects of optical disks for digital sound recordings. Part 1-1 specifies DVD optical disk, Part 1-2 specifies BD optical disk. Part 2 wh
32、ich specifies the minimum requirements for digitization of content, format of digitised content, content information and media inspection. PD IEC/TS 62702-2:2016 6 IEC TS 62702-2:2016 IEC 2016 AUDIO ARCHIVE SYSTEM Part 2: Audio data preservation 1 Scope This part of IEC 62702, specifies the requirem
33、ents for digitization of audio data for audio preservation. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the la
34、test edition of the referenced document (including any amendments) applies. IEC 62227, Multimedia home server systems Digital rights permission code 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 audio archive archive that consists of audio
35、data preservation 3.2 audio data preservation data of audio stored in physical media for preservation 3.3 AIP archival information package 3.4 dissemination distribution of preserved audio content to users 3.5 objective media media whose storage is based on impartial criteria 4 Objective media inspe
36、ction 4.1 Criteria of the objective media In order to objectively determine whether recorded audio content should be digitised and migrated to an archival media for long term preservation, the following criteria should be applied. Evaluate the availability of the media and its playback means in the
37、long term with consideration to the format of the media; whether the media specification is internationally PD IEC/TS 62702-2:2016IEC TS 62702-2:2016 IEC 2016 7 standardized or publically accessible and available. If the availability is limited in its lifespan, i.e. less than the archive systems tar
38、get term, then the media is worth preserving. Evaluate the degradation of the media. If the degradation of the media causes degradation of the reproduction, of sound, or if playback is difficult, then the media should be preserved. Evaluate the continuity of the organization that possesses the media
39、 to determine whether the media should be preserved. 4.2 Criteria of the archival media for preservation and dissemination To determine what kind of media should be used for archival media for preservation and dissemination media, the following criteria should be applied. For archival media, evaluat
40、e the long term availability, durability and energy efficiency. However, it depends on the policy of the archive organization. For dissemination of media, evaluate the media format of availability, popularity, availability of reproduction devices or software. Copy protection or rights management sys
41、tems are considered if the content is copyrighted. If rights management systems apply, see IEC 62227. 5 Digitization of audio content 5.1 Condition and environment The objective media has its own original characteristics of reproduced sound quality. The condition and environment including digitise e
42、quipment should be determined to guarantee the original sound quality of audio content. The sound quality factors are: S/N ratio; frequency characteristics; frequency deviation (jitter, wow-flatter). 5.2 Digitization method 5.2.1 Content of analogue media 5.2.1.1 System The digitization of analogue
43、signals of analogue media is described in Figure 1. Figure 1 Digitization of analogue signals There are various types of signal processing methods with respect to the analogue output signal. The choice of method depends on the policy of preservation. If all signals are preserved exactly as they are,
44、 signal processing is not applied. Signal processing is used to enhance or modify audio signals. For noise reduction, or any compensation for noise of the audio signal of content, see Annex C. IEC Media Player Signal processing A/D converter Digital output Analogue output PD IEC/TS 62702-2:2016 8 IE
45、C TS 62702-2:2016 IEC 2016 5.2.1.2 Digital signal format The player of the analogue media reproduces analogue signals. An analogue to digital converter digitises that analogue signal to digital data. The basic format of analogue to digital conversion is described in Table 1. Table 1 Digital signal f
46、ormat Codec Liner PCM Sampling frequency 48 kHz or 96 kHz Bit length 24 bit Channels Same as the analogue content The sampling frequency depends on the content frequency characteristic. For instance, LP analogue records have a frequency response over 30 kHz that may be utilized for a 4 channel appli
47、cation, in this case 96 kHz sampling is recommended. 5.2.1.3 Audio file format The file format for digital signals is is described in Table 2. Table 2 File format File format BWF RIFF/WAVE 5.2.1.4 Information of time code or address Content of analogue media may not have a time code or address infor
48、mation. Mostly playing time information is provided separately by other media. Playing time, or start and end time or address of an audio track may not be provided. However, after digitization, the time code or address can be embedded in digitised content or provided separately. All information conc
49、erning time code or address of audio track of analogue media should be provided. 5.2.2 Content of digital media 5.2.2.1 System The player of the digital media reproduces analogue and/or digital signals. If the available player has only an analogue signal output, a digital signal before an A/D converter in the player should be used as a reproduced signal. In case an available player has a digital audio signal output or interface, a reproduced signal is obtained from
