1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS EN 60843-4:2001 IEC 60
2、843-4:2000 The European Standard EN 60843-4:2000 has the status of a British Standard ICS 33.160.40 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Helical-scan video tape cassette system using 8 mm magnetic tape (8 mm video) Part 4: Video subcode (VSC)This British Standard, h
3、aving been prepared under the direction of the Electrotechnical Sector Committee, was published under the authority of the Standards Committee and comes into effect on 15 April 2001 BSI 04-2001 ISBN 0 580 36848 3 BS EN 60843-4:2001 Amendments issued since publication Amd. No. Date Comments National
4、foreword This British Standard is the official English language version of EN 60843-4:2000. It is identical with IEC 60843-4:2000. The UK participation in its preparation was entrusted by Technical Committee EPL/100, Audio, video and multimedia systems and equipment, to Subcommittee EPL/100/2, Recor
5、ding, which has the responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promu
6、lgate them in the UK. A list of organizations represented on this subcommittee can be obtained on request to its secretary. From 1 January 1997, all IEC publications have the number 60000 added to the old number. For instance, IEC 27-1 has been renumbered as IEC 60027-1. For a period of time during
7、the change over from one numbering system to the other, publications may contain identifiers from both systems. Cross-references Attention is drawn to the fact that CEN and CENELEC Standards normally include an annex which lists normative references to international publications with their correspon
8、ding European publications. The British Standards which implement these international or European publications may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalo
9、gue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document compr
10、ises a front cover, an inside front cover, the EN title page, pages 2 to 26, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued.Page2 EN608434:2000 BSI 04-2001 CONTENTS Page Clause 1 General . 5 1.1 Scope. 5 1.2 Norm
11、ative references . 5 2 Area allocation and dimensions . 5 2.1 Types of video subcode (VSC) 5 2.2 1 block VSC 5 2.3 5 block VSC 5 3 Data structure 6 3.1 1 block VSC 6 3.2 5 block VSC 6 4 Channel coding 6 4.1 Modulation 6 4.2 Transmission rate. 6 4.3 Erase code . 6 4.4 Search mark . 6 4.5 Synchronizat
12、ion code . 7 4.6 End mark 7 5 Data contents 7 5.1 Block 7 5.2 Word 7 5.3 CRC code and error detection. 7 5.4 Mode 7 6 Recording method of mode data (Block 4) . 8 6.1 Time code. 8 6.2 Recording date/Recording time. 8 6.3 Video control code 8 6.4 Pre-recorded tape modes . 8 Annex A (normative) Code as
13、signment 19 Annex B (informative) Pre-recorded tape . 25 Annex ZA (normative) Normative references to international publications with their corresponding European publications 26 Figure 1 Area allocation and dimensions of 1 block VSC. 9 Figure 2 Area allocation and dimensions of 5 block VSC with PCM
14、 audio 10 Figure 3 Area allocation and dimensions of 5 block VSC without PCM audio. 11 Figure 4 1 block VSC 12 Figure 5 5 block VSC 13 Figure 6 Synchronization code 14 Page3 EN608434:2000 BSI 04-2001 Page Table 1 Search mark. 14 Table 2 Block contents 14 Table 3 Word contents 15 Table 4 Mode content
15、s 15 Table 5 Time code (525 line 60 field system) 15 Table 6 Time code (625 line 50 field system) 16 Table 7 Recording date/Recording time (525 line 60 field system) 16 Table 8 Recording date/Recording time (625 line 50 field system) 16 Table 9 Recording length 17 Table 10 Pre-recorded tape (525 lin
16、e 60 field system) 17 Table 11 Pre-recorded tape (625 line 50 field system) 18 Table A.1 Control command 20 Table A.2 Numeral code 24 Table B.1 Structure of pre-recorded tape. 25 Page4 EN608434:2000 BSI 04-2001 HELICAL-SCAN VIDEO TAPE CASSETTE SYSTEM USING 8 mm MAGNETIC TAPE (8 mm VIDEO) Part 4: Vid
17、eo subcode (VSC) 1 General 1.1 Scope This part of IEC 60843 specifies a method of auxiliary data recording and playback with the IEC 60843 8 mm video system. This part is applicable to both 525 line 60 field and 625 line 50 field television systems. 1.2 Normative references The following normative d
18、ocuments contain provisions which, through reference in this text, constitute provisions of this part of IEC 60843. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this part of IEC 60843 are encouraged t
19、o investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of IEC and ISO maintain registers of currently valid International Standards. IEC 60461:198
20、6, Time and control code for video tape recorders IEC 60843 (all parts), Helical-scan video tape cassette system using 8 mm magnetic tape 2 Area allocation and dimensions 2.1 Types of video subcode (VSC) There are two types of VSC which are 1 block VSC and 5 block VSC. 2.2 1 block VSC Figure 1 shows
21、 the recording area of 1 block VSC. The recording area of 1 block VSC shall be specified by the head switching point. All of the data area, search mark and erase code should be recorded. 2.3 5 block VSC 2.3.1 5 block VSC with PCM audio Figure 2 shows the recording area of 5 block VSC with PCM audio.
22、 The recording area of 5 block VSC with PCM audio shall be specified by the distance from the head switching point. Page5 EN608434:2000 BSI 04-2001 All the data area, search mark and erase code should be recorded. The erase code should have a variable length relative to the position of PCM data area
23、. 2.3.2 5 block VSC without PCM audio Figure 3 shows the recording area of 5 block VSC without PCM audio. The recording area of 5 block VSC without PCM audio shall be specified by the distance from the head switching point. All of the data area, search mark and erase code should be recorded. 3 Data
24、structure 3.1 1 block VSC Figure 4 shows the data area of 1 block VSC. 1 block VSC consists of a block named Block 4. Block 4 is common to 5 block VSC and 1 block VSC. 3.2 5 block VSC Figure 5 shows the data area of 5 block VSC. 5 block VSC has an extended data area from Block 0 to Block 3. 4 Channe
25、l coding 4.1 Modulation The modulation method shall be a bi-phase mark, except for the synchronization code. 4.2 Transmission rate The transmission rate shall be 368 times the horizontal sync frequency, 5,79 Mbit/s for the 525 line 60 field system and 5,75 Mbit/s for the 625 line 50 field system. 4.
26、3 Erase code The erase code shall be all “1”. 4.4 Search mark The data sign of the search mark shall be all “0” for enable. Page6 EN608434:2000 BSI 04-2001 The data sign of the search mark shall be all “1” for disable. Table 1 shows the recording condition of the search mark. 4.5 Synchronization cod
27、e Figure 6 shows the synchronization code. The synchronization code indicates the start position of each CRC block. 4.6 End mark The end mark shows the end of the data area. The end mark consists of 12 successive synchronization codes. 5 Data contents 5.1 Block Table 2 shows the contents of the bloc
28、k. A block consists of the synchronization code, five words and the CRC code. Blocks from Block 0 to Block 3 shall be used with 5 block VSC only. Block 4 is common to 5 block VSC and 1 block VSC. 5.2 Word Table 3 shows the contents of the word. Word 0 shows the mode which indicates a category of dat
29、a code. Words from Word 1 to Word 4 consist of the data code for the mode. 5.3 CRC code and error detection The error detection system shall be based on the CRC method. The CRC block consists of five words and the CRC code. The CRC code contains 8 bits and its generator polynomial G(x) shall be as f
30、ollows:MSB LSB G(x) = 8 + 1 (preset “11001100“) 5.4 Mode Table 4 shows the outline of the contents of the mode. See annex A for details. Page7 EN608434:2000 BSI 04-2001 6 Recording method of mode data (Block 4) 6.1 Time code 6.1.1 Basic recording rules The time code shall be recorded on all the trac
31、ks if it is not necessary to record other data. If other data are recorded, by replacing some of the time code data, the time code shall be recorded at least by the pattern specified in 6.1.2. 6.1.2 Recording patterns Tables 5 and 6 show the recording conditions of the time code. 6.2 Recording date/
32、Recording time 6.2.1 Basic recording rules The recording date/recording time shall be recorded on the specific track simultaneously with the time code. The recording date and the recording time shall be recorded simultaneously. 6.2.2 Recording patterns Tables 7 and 8 show the recording conditions of
33、 the recording date/recording time. 6.3 Video control code The contents shall be indicated in accordance with clause A.4. 6.3.1 Recording rules The video control code shall be recorded on the same track as the other data. Both video control code and time code shall be recorded. For pre-recorded tape
34、, the video control code shall be recorded on the track on which the next chapter code is permitted to be recorded. 6.3.2 Recording length Table 9 shows the recording length of the video control code. 6.4 Pre-recorded tape modes 6.4.1 Contents of mode Pre-recorded tape can deal with four modes: the
35、present chapter, the next chapter, the pre- recorded tape ID and the total time/total chapter numbers in addition to the time code. The “time code” shows the time elapsed in the active programme. The “present chapter” shows the chapter number at the tape position and the time elapsed in the chapter.
36、 Page8 EN608434:2000 BSI 04-2001 The “next chapter” shows the next chapter number and the remaining time of the present chapter. The “pre-recorded tape ID” indicates the pre-recorded tape. The “total time/total chapter number” shows the total chapter number and the time elapsed in the active program
37、me. 6.4.2 Basic recording rules All the data should be recorded according to the rules shown in tables 10 and 11. The present chapter and the next chapter shall be recorded in pairs. The pre-recorded tape ID and the total data shall be recorded in pairs. The time code and the chapter number of the p
38、resent chapter are mandatory. The time code shall be based on a non-drop frame sequence. The length of each chapter shall be more than 2 min. 6.4.3 Recording patterns Tables 10 and 11 show the recording patterns of pre-recorded tape. Erase code Search mark Data area Video overlap After recording mar
39、gin Direction of head motion PCM data area * 2,3 H (2,8 H) * 1,0 H(1,0 H) * 1,0 H(1,3 H) * 0,24 H (0,24 H) VSC area Video Head switching position IEC 121/2000 Key *: 525 line 60 field system (): 625 line 50 field system H: horizontal scanning line The figure is viewed from the magnetic coating side.
40、 NOTE The tolerance of the distance from the switching position to the end of the data area along the track is: (2,3 0,75) H for the 525 line 60 field system; (2,8 0,90) H for the 625 line 50 field system. Figure 1 Area allocation and dimensions of 1 block VSC Page9 EN608434:2000 BSI 04-2001 Erase c
41、ode Search mark Video overlap After recording margin Direction of head motion PCM data area * 2,3 H (2,8 H) * 1,0 H(1,0 H) VSC area Video Head switching position * 0,8 H(0,8 H) Data area 0,1 H IEC 122/2000 Key *: 525 line 60 field system (): 625 line 50 field system H: horizontal scanning line The f
42、igure is viewed from the magnetic coating side. NOTE The tolerance of the distance from the switching position to the end of the data area along the track is: (2,3 0,75) H for the 525 line 60 field system; (2,8 0,90) H for the 625 line 50 field system. Figure 2 Area allocation and dimensions of 5 bl
43、ock VSC with PCM audio Page10 EN608434:2000 BSI 04-2001 Erase code Search mark Video overlap Direction of head motion * 2,3 H (2,8 H) * 1,0 H(1,0 H) VSC area Video Head switching position * 0,8 H(0,8 H) Data area * 3,5 H(3,9 H) IEC 123/2000 Key *: 525 line 60 field system (): 625 line 50 field syste
44、m H: horizontal scanning line The figure is viewed from magnetic coating side. NOTE The tolerance of the distance from the switching position to the end of the data area along the track is: (2,3 0,8) H for the 525 line 60 field system; (2,8 1,0) H for the 625 line 50 field system. Figure 3 Area allo
45、cation and dimensions of 5 block VSC without PCM audio Page11 EN608434:2000 BSI 04-2001 * Sync Erase code Search mark Data area Recording direction Block 4 * End 36 bits 51 bits 1 CRC Block ( 48 bits ) 3 bits 8 bits 8 bits 8 bits 8 bits 8 bits 8 bits Word 0 Word 1 Word 2 Word 3 Word 4 CRCC B0 B1 B2
46、B3 B4 B5 B6 B7 8 bits LSB MSB IEC 124/2000 Key *Sync: synchronization code *End: end mark Figure 4 1 block VSC Page12 EN608434:2000 BSI 04-2001 * Sync Erase code Search mark Data area Recording direction Block 0 * End 36 bits 51 bits 1 CRC Block ( 48 bits ) 3 bits 8 bits 8 bits 8 bits 8 bits 8 bits
47、8 bits Word 0 Word 1 Word 2 Word 3 Word 4 CRCC B0 B1 B2 B3 B4 B5 B6 B7 8 bits LSB MSB Block 1 Block 2 Block 3 Block 4 IEC 125/2000 Key *Sync: synchronization code *End: end mark Figure 5 5 block VSC Page13 EN608434:2000 BSI 04-2001 Bit interval T 1,5 T 1,5 T 0 1 1 0 1 0 0 1 Synchronization code IEC
48、126/2000 NOTE The frequency of the synchronization code shall be 368/3 times the horizontal sync frequency. Figure 6 Synchronization code Table 1 Search mark 525 line 60 fieldsystem 625 line 50 fieldsystem Search mark SP a : from 10 s to 11 s Recording time LP b : from 15 s to 16 s NOTE The recommen
49、ded recording interval is 1 min minimum. a SP: standard play b LP: long play Table 2 Block contents Block number Contents Block 0 Block 1 Extension blocks Block 2 (5 block VSC only) Block 3 Block 4 Common blocks Page14 EN608434:2000 BSI 04-2001 Table 3 Word contents Word number Contents Word 0 Mode number Word 1 Word 2 Data code Word 3 Word 4 Table 4 Mode contents Mode number (hexa) Co
