1、- CENELEC ENxbL237-3 95 I 3404583 0163543 605 m BRITISH STANDARD Broadcast video tape recorders - Methods of measurement Part 3. Electrical measurements for analogue component video signals The European Standard EN 61237-3 : 1995 has the status of a British Standard CDC 621.397,458 : 621.317.08 BS E
2、N 61237-3 1995 IEC 1237-3 : 1995 ,incorporating corrigendum ipnl 1995) - CENELEC ENxbL237-3 95 W 3404583 0163544 541 = BS EN 612373 : 1995 This British Standard, having been prepared under the direction of the Electrotechnical Sector Board, was published under the authority of the Standards Board an
3、d comes into effect on 15 November 1995 O BSI 1995 Committees responsible for this British Standard The prepamtion of this British Standard was entnisted to Technical Committee EPU, Recording, upon which the following bodies were represented Association of Professional Recording Services Limited Aud
4、io Engineering Society British Broadcasting Corporation British Kinematograph, Sound and Television Society British we Industry Association Federation of the Electronics Industry ITV Association (ITVA) National Council for Educational Technology (NCET) Royal Photographic Society Royal Television Soc
5、iety Amendments issued since publication I Textaffected The following BSI references relate to the work on this standard Committee reference EPUGO Draft for comment 913063 DC ISBN O M(0 24679 5 CENELEC ENxbL237-3 95 W 3404583 0163545 488 BS EN 612373 : 1995 Contents Committees responsible National f
6、oreword Page Inside front cover Foreword Text of EN 61237-3 2 4 1 CENELEC EN*bL237-3 95 3404583 0363546 314 BS EN 612373 : 1995 National foreword This British Standard has been prepared by Technical Committee and is the English ianguage version of EN 612373 : 1995 Broadcast video tape recm - Methods
7、 of measurement Part 3: Electrical measurements for analogue component video szgnacS, published by the European Committee for Electrotechnical Standardization (CENELEC). It is identical with IEC 12373 : 1995 including the corrigendum of April 1995, published by the Intemational Electrotechnical Comm
8、ission (IEC). It is envisaged that BS EN 61237 wiil consist of the following parts: Part 1 Mechanical measurements Part 2 Electrical rneasurmts of analogue component video signals Part 3 Electrical measurements of analogue component video signals Part 4 Measurements of audio perjrmunce Part 5 Electr
9、ical measurements of digital composite video signds and digital audio SipUdS Part 6 Electrical measuremenh of digital component video signals and digital audio SignUl!S Cross-references Intemational standard Corresponding British Standard EN 60961 : 1994 (IEC 961 : 1993) EN 61105 : 1993 (IEC 1105 :
10、1991) HD 439 s1: 1983 (IEC 698 : 1981) Compliance with a British Standard does not of itself confer immunity from legal obligations. BS EN 60961 : 1994 Specifiation for helical-scan video tape cassette system using 12.65 mm (0.5 in) magnetic tape on twe L BS EN 61105 : 1994 Specification for wfrence
11、 tapes for video tape recorder systems BS 6311 : 1982 MeuzOds for measuring tekwiswn tape machine pammetea ii CENELEC ENxbL237-3 95 3404583 OLL13547 250 .I EUROPEIN STANDARD NORRE EUROPENNE EUROPAZSCHE NORM EN 612373 Febniary 1995 UDC 621.397.452:621.317.08 Descriptors: Electroacoustics, video recor
12、ding, recording apparatus, video tape recorders, radiocommunications, electrical measurements, video signals, analogue signals English version Broadcast video tape recorders - Methods of measurement Part 3: Electrical measurements for analogue component video signals (IEC 1237-3 1995) Magntocopes de
13、 radiodiffusion - Mthodes de mesure Partie 3 Mesures lectriques pour les signaux vido analogiques composantes Videobandgerte fr den Rundfunk Mefiverfahen Teil 3: Elekrische Messungen fur Videosignale mit analogen Komponenten (IEC 1237-3 : 1995) (CE1 1237-3 : 1995) This European Standard was approved
14、 by CENELEC on 1994-03-08. 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
15、 standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language an
16、d notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerl
17、and and United Kingdom. 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 O 1995 Copyright reserved to CENELEC members Ref. No. EN 6
18、1237-3 : 1995 E Page 2 EN 61237-3 : 1995 Foreword The text of document 60B(C0)160 + 1604 future edition 1 of IEC 1237-3, prepared by SC 60B, Video recording, of IEC TC 60, Recording, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61237-3 on 1994-0308. The following
19、dates were xed - latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 19964241 latest date by which the national standards conflicting with the EN have to be withdrawn - (dow) 1996-02-01 Annexes designated normat
20、ive are part of the body of the standard. Annexes designated informative are given for information oniy. In this standard, annex ZA is node and annex A is informative. Annex ZA has been added by CENELEC. CENELEC EN*bL237-3 95 3404583 0163549 023 Page 3 EN 61237-3 : 1995 CONTENTS Clause Scope and obj
21、ect Normative references . General : . Test conditions Measuring methods and test signals . 5.1 Manual and automatic methods of measurement . 5.2 Measurement of differences between adjacent tracks (fields/segments) 5.3 Procedure of measurement . 5.4 Test signals . Measurement of characteristics 6.1
22、6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 6.1 O 6.1 1 6.1 2 6.13 6.14 6.15 6.16 6.17 6.18 6.19 6.20 6.21 6.22 Luminance bar amplitude error . Synchronizing pulse amplitude error Bar tilt . Pulse/bar ratio error Pulse shape distortion Amplitude/video-frequency characteristic Chrominance-luminance gain inequali
23、ty Chrominance-luminance delay inequality Line-time non-linearity High-frequency non-linearity High-frequency intermodulation . Crosstalk between channels Luminance random noise . Chrominance random noise . Group delay 4 4 5 5 6 6 6 6 7 9 9 10 11 Il 12 13 13 14 15 16 16 17 18 19 19 FM characteristic
24、 frequencies 20 Jitter 21 Velocity errors 23 Moir . 23 Noise reduction 24 Coder alignment 24 Power-supply interference 24 Figures 25 . Annexes ZA (normative) Other international publications quoted in this standard with the A (informative) Bibliography 38 references of the relevant European publicat
25、ions . 39 CENELEC EN*bL237-3 75 I 3404583 0363550 845 I Page 4 EN 61237-3 : 1995 BROADCAST VIDEO TAPE RECORDERS - METHODS OF MEASUREMENT Part 3: Electrical measurements for analogue component video signals 1 Scope and object This pari of IEC 1237 describes the test signals and measurement methods fo
26、r equipment mainly dedicated to record/playback of analogue component TV signals on magnetic tape on reels or in cassettes. It may also be applied for measuring methods for general use in television production and transmission. The allowable tolerances for the rated values for acceptable performance
27、 are not given in this standard, but may be derived from appropriate system specif ications, manufacturers specif ications, etc. The necessary reference and calibration tapes are either mentioned in the specific IEC Publication of the equipment under test or included in IEC i 105 (reference tapes) a
28、nd IEC technical report 1295 (calibration tapes) i. The methods are applicable to acceptance tests, performance comparisons and, as far as possible, to routine checks. The principal object of this document is to describe the methods of measurement, test signals and procedures which may apply to char
29、acteristics of video recording/playback machines mainly intended for professional use. The measuring methods described hereafter do not directly concern home equipment and it would appear that some will be difficult to apply to them. 2 Normative references The following normative documents contain p
30、rovisions which, through reference in this text, constitute provisions of this pari of IEC 1237. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this part of IEC 1237 are encouraged to investigate the possibilit
31、y of applying the most recent editions of the standards indicated below. Members of IEC and IS0 maintain registers of currently valid International Standards. IEC 961 : 1993, Helical-scan video tape cassette system using 72,65 mm (03 in) magnetic tape on type L Figures in square brackets refer to an
32、nex A, Bibliography. CENELEC EN*b3237-3 75 3404583 O363553 7L = Page 5 EN 61237-3 : 1995 IEC 1 105: 1 991, Reference tapes for video tape recorder systems ITU-R Recommendation 471 -1 : 1990, Nomenclature and description of colour bar signals (Vol. XI-1) ITU-R Recommendation 567-3: 1990, Transmission
33、 performance of television circuits designed for use in international connections (Vol. XII) ITU-R Recommendation 601 -2: 1990, Encoding parameters of digital television for studios (Vol. XI-1) ITU-R Recommendation 656: 1986, Interfaces for digital component video signals in 525-line and 625-line te
34、levision systems (Vol. Xl-I) 3 General To ensure that the results obtained at a specific time at a specific place are comparable to other measurements, it is advisable to specify the test signals, measuring devices and types of tapes used together with results obtained. Since measurements of televis
35、ion tape machines on the basis of a single test-line per field may not be fully representative of the full-field performance (see 5.1 and 5.2), they may give results which differ from those obtained or calculated with full-field test signals. Therefore it is necessary to additionally specify the mea
36、suring method: - single line measurement (line number); - block measurement (start-line, step-by-step line(s), number of steps); - full-field measurement. Additionally, it should be stated if the selection of lines coincides with a single record/playback head only. 4 Test condltlons If not otherwise
37、 stated all measurements shall be carried out at the following atmospheric conditions: Temperature (20 f 1) “C Relative humidity (50 f 2) % Air pressure 86 kPa to 106 kPa Conditioning before testing 24 h CENELEC EN*bL237-3 75 W 3404583 0163552 bLB Page 6 EN 61237-3 : 1995 5 Measuring methods and tes
38、t signals 5.1 Manual and automatic methods of measurement If automatic measuring apparatus is designed to give reliable results under the special conditions of television tape playback as e.g. drop-out, jitter, noise, time-base errors, suppression of vertical blanking interval or insufficient head-t
39、o-tape contact, a significant improvement in measurement speed, accuracy and comparability of results can be achieved. Therefore preference was given to measurement methods which can be carried out by automatic measuring equipment or which are suitable for automatic measuring techniques. Except wher
40、e a distinction is made in particular clauses between manual and automatic methods of measurement, the measurement procedures given in this standard are valid for both methods. However, although in the case of automatic measurements the procedure is carried out automatically by the test signal analy
41、zer, the various steps are described as if they were performed manually. 5.2 All currently standardized recording formats make use of segmented recording techniques. The length of the segments (tracks) varies between approximately 16 lines and one field where the latter is often termed “non-segmente
42、d recording“ which only indicates that there is no cut within the field. Measurement of differences between adjacent tracks (fields/segments) Since two or more heads are used for record and playback of the video information to and from the tracks, it is desirable to restrict the measurement to segme
43、nts or tracks related to a specific head. This requires a special signal arrangement which provides identical information to the heads or segments in turn. A suitable arrangement for most formats is to repeat a packet of up to 16 different signals of a duration of one line within a field and to make
44、 the signals identical in both fields 2. 5.3 Procedure of measurement The measurements shall be carried out by measuring the playback signal after recording on the same machine (best-case configuration). Before testing the overall performance, the playback channel shall be measured by means of a cal
45、ibration tape (see clause 1). In certain particular cases, if the multigeneration performance of a video recording system is measured, the measurements shall be carried out by measuring the playback signal after recording on a different machine (worst-case configuration). If the television tape mach
46、ine under test is equipped with external controls, e.g. tracking control, gain control, etc., these controls shall be set to their preset- or mid-position for all measurements. CENELEC EN*b2237-3 95 P 3404583 0163553 554 M Sync Page 7 EN 61237-3 : 1995 -300 42.8 -300 42,8 5.4 Test signals 5.4.1 Intr
47、oduction A representative range of test signals is shown in figures 1 to 10. For ease of reference, they are indicated by roman numerals. Other test signals not shown in the figures are collected in 5.4.2. All signals are defined as a luminance and two colour-difference signals. In practice, these s
48、ignals are generally represented by the symbols Y, B-Y, R-Y, but in the following a short form of the notation adopted by the ITU-R (Ey, EcB and EcR) has been used: Y$, and CR These components are defined in terms of the primary signals R, G and B by: Y = 0,587 . G + 0,299 3 R + 0,114. B, Cs = 0,564
49、 (B-Y), CR = 0,713 (R-Y) It should be noted that some of the test signals will produce “illegal“ values of R, G, B or composite if dematrixed and/or coded. 5.4.2 The amplitude of the signals is given in per cent of full-picture amplitude of the luminance and/or chrominance signals. The nominal full amplitude shall be identical but may differ between systems. The preferred levels given in table 1 are those defined by the common EBUISMPTE Standard (EBU N10, SMPTE 253) (3 and 4). They are in use in all 625-line countries. In 525-line countries several oth
