1、BRITISH STANDARD BS EN 61041-2:1996 BS7434-2: 1996 IEC1041-2: 1994 Methods of measurement Non-broadcast video tape recorders Part 2: Video characteristics chrominance SECAM The European Standard EN61041-2:1996 has the status of a BritishStandard ICS 33.160.40BSEN61041-2:1996 This BritishStandard, ha
2、ving been prepared under the directionof the Electrotechnical Sector Board, was published underthe authority of the Standards Board and comesintoeffect on 15July1996 BSI04-2000 The following BSI reference relates to the work on this standard: Committee reference EPL/100/2 ISBN 0 580 26119 0 Committe
3、es responsible for this BritishStandard The preparation of this BritishStandard was entrusted by Technical Committee EPL/100, Audio, video and multimedia systems and equipment, to Subcommittee EPL/100/2, Recording, upon which the following bodies were represented: Association of Professional Recordi
4、ng Services Limited British Broadcasting Corporation British Kinematograph, Sound and Television Society British Radio and Electronic Equipment Manufacturers Association British Tape Industry Association Federation of the Electronics Industry Independent Television Association (ITVA) Royal Televisio
5、n Society Amendments issued since publication Amd. No. Date CommentsBSEN61041-2:1996 BSI 04-2000 i Contents Page Committees responsible Inside front cover National foreword ii Foreword 2 Text of EN61041-2 3 List of references Inside back coverBSEN61041-2:1996 ii BSI 04-2000 National foreword This Br
6、itishStandard has been prepared by Subcommittee EPL/100/2 and is the English language version of EN61041-2:1996, Non-broadcast video tape recorders Methods of measurement Part2: Video characteristics chrominance SECAM, published by the European Committee for Electrotechnical Standardization (CENELEC
7、). It is identical with IEC1041-2:1994, published by the International Electrotechnical Commission (IEC). For ease of reference to other Parts of BS7434, this standard has also been designated as BS7434-2. This BritishStandard was not circulated for public comment as it is only used within the Frenc
8、h television system. IEC1041 consists of the following parts: Part1: General video (NTSC/PAL) and audio (longitudinal) characteristics; Part2: Video characteristics chrominance SECAM; Part3: Audio characteristics for FM recording. A British Standard does not purport to include all the necessary prov
9、isions 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. Cross-references Publication referred to Corresponding British Standard EN61041-1:1995 (IEC1041-1:1994) BS EN6
10、1041 Non-broadcast video tape recorders. Methods of measurement Part1:1995 aGeneral video (NTSC/PAL) and audio (longitudinal) characteristics a Also designated as BS7434-1. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, theEN title page, pages2 to12, an
11、inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN61041-2 January1996 ICS 33.160.40 Descriptors:
12、 Recording apparatus, video recording, magnetoscopes, frequency modulation, measurements, characteristics, chrominance, cross talk, luminance English version Non-broadcast video tape recorders Methods of measurement Part2: Video characteristics chrominance SECAM (IEC1041-2:1994) Magntoscopes hors ra
13、diodiffusion Mthodes de mesure Partie2: Caractristiques vido chrominance SECAM (CEI1041-2:1994) Videobandgerte fr den Gebrauch auerhalb des Rundfunks Meverfahren Teil2: Videoeigenschaften Chrominanz SECAM (IEC1041-2:1994) This European Standard was approved by CENELEC on1995-11-28. CENELEC members a
14、re 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 be obtained on application to
15、 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 and notified to the Central Secretariat has th
16、e 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, Switzerland and United Kingdom. CENELEC European Com
17、mittee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels 1996 Copyright reserved to CENELEC members Ref. No. EN61041-2:1996 EEN61041-2:1996 BSI 04-2000 2 Forew
18、ord The text of the International Standard IEC1041-2:1994, prepared by SC100B, Recording, of IEC TC100, Audio, video and multimedia systems and equipment, was submitted to the formal vote and was approved by CENELEC as EN61041-2 on1995-11-28 without any modification. The following dates were fixed:
19、Annexes designated “normative” are part of the body of the standard. Annexes designated “informative” are given for information only. In this standard, Annex ZA is normative and Annex A is informative. Annex ZA has been added by CENELEC. Contents Page Foreword 2 1 Scope 3 2 Normative references 3 3
20、General 3 4 Chrominance amplitude frequency response 3 5 Chrominance signal-to-noise ratio 3 6 Luminance-to-chrominance crosstalk 4 7 Chrominance-to-luminance crosstalk 5 8 Chrominance-to-luminance displacement 5 Annex A (informative) Colour bar signal 11 Annex ZA (normative) Normative references to
21、 international publications with their corresponding European publications 11 Figure 1 Chrominance amplitude frequency response 6 Figure 2 Chrominance signal-to-noise ratio 7 Figure 3 Luminance-to-chrominance crosstalk 8 Figure 4 Chrominance-to-luminance crosstalk 9 Figure 5 Chrominance-to-luminance
22、 displacement 10 latest date by which the ENhas to be implemented at national level by publication of an identical national standard or by endorsement (dop)1996-12-01 latest date by which the national standards conflicting with the EN haveto be withdrawn (dow)1996-12-01EN61041-2:1996 BSI 04-2000 3 1
23、 Scope This part of IEC1041 describes the measurement methods to evaluate the chrominance performance in SECAM non-broadcast video tape recorders. Because of the frequency modulation used in the SECAM system, special methods of measurement are required for testing the chrominance performance. 2 Norm
24、ative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this part of IEC1041. At the time of publication, the editions indicated were valid. All normative documents are subject to revision, and parties to agreements based
25、on this part of IEC1041 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. IEC1041-1:1990, Non-broadcast video tape recorders Methods of m
26、easurement Part1: General video (NTSC/PAL) and audio (longitudinal) characteristics. CCIR Recommendation471-1, Nomenclature and description of colour bar signals. 3 General The general requirements given in section1, and the methods of measurement described in sections2,4 and5 of IEC1041-1 are appli
27、cable. 4 Chrominance amplitude frequency response 4.1 This measurement determines the amplitude frequency response of the chrominance channel. 4.2 The circuit arrangement shall be as shown in Figure 1. 4.3 The test signal shall be as shown in Figure 1. The sinusoidal sweep signal(0,1MHz to1MHz) is p
28、resent during the active part of the field and has a peak-to-peak amplitude of300mV superimposed on a50% pedestal. This signal has no sync pulse. 4.4 Put the switch SW1 in position1 in order to check the demodulator amplitude frequency response of the chrominance channel. The amplitude V p-pof the o
29、utput signal at each frequency(100kHz250kHz500kHz) shall be measured on the (R-Y) signal and the (B-Y) signal. The peak-to-peak amplitude at each of the above-mentioned frequencies shall be related to the reference level V refat100kHz. The amplitude frequency response is given by the following formu
30、la: 4.5 Put the switch SW1 in position2 in order to check the amplitude frequency response of the chrominance channel of the VTR. The amplitude at each marker on the (R-Y) signal and the (B-Y) signal shall be measured as mentioned in4.4. 4.6 The amplitude/frequency response of (R-Y) and (B-Y) channe
31、ls of the VTR shall be reported taking into account the demodulator response obtained in4.4 if this one is not flat from zero to500kHz. 5 Chrominance signal-to-noise ratio 5.1 This measurement determines the noise behaviour of the chrominance channel. 5.2 The circuit arrangement shall be as shown in
32、 Figure 2. 5.3 The test signal shall be a full-field blue or red SECAM signal corresponding to the blue or red part of the100/0/75/0 colour bars defined in CCIR Recommendation471-1. 5.4 The measurement of the chrominance signal-to-noise ratio is made as explained below. 5.4.1 Put the SW2 switch in p
33、osition1 in order to measure the demodulator noise level on (R-Y) and (B-Y) signals, SW1 being in position1 and2 respectively.EN61041-2:1996 4 BSI 04-2000 The noise level (r.m.s.) will be taken as NR0 for (R-Y) and NB0 for (B-Y). 5.4.2 Put the SW2 switch in position2 and record the red signal on one
34、 tape section and then the blue signal on another one. 5.4.3 During playback of both sections, make the following measurements on (R-Y) and (B-Y) signals: The noise level (r.m.s.) taken as NR1 and NB1 respectively. The peak-to-peak signal level taken as VR1 and VB1 respectively. 5.4.4 The chrominanc
35、e signal-to-noise ratio of the VTR under test is given as follows: 5.5 The results of measurement shall be stated in the unweighted value of the S/N (dB) obtained in (R-Y) and (B-Y) output. 6 Luminance-to-chrominance crosstalk 6.1 This measurement determines the degree of crosstalk of FM-luminance s
36、idebands into the down-converted chrominance band, being demodulated as unwanted colour signals (the so-called “crosscolour”). 6.2 The circuit arrangement is shown in Figure 3. 6.3 The following two test signals shall be used: a) A full-field grey signal having a luminance amplitude of350mV (C in Fi
37、gure 3) with superimposed chrominance subcarrier (in Figure 3). b) A sinusoidal frequency sweep signal(0,5 MHz to2,5MHz) having a period of one active line and a peak-to-peak amplitude of300mV (D in Figure 3). This signal must be superimposed on signal of Figure 2 specified ina), the mixed signal be
38、ing given in , Figure 3. 6.4 The measurement of the crosstalk is made as follows: 6.4.1 Put the SW1 switch in position1 in order to check the chrominance signal-to-noise ratio when the test signal is a full-field grey signal (in Figure 3). The signal-to-noise ratio shall be measured on the (R-Y) and
39、 (B-Y) output signals. These figures shall be S/N.R0 and S/N.B0 respectively in unweighted value. 6.4.2 Put the SW1 switch in position2 in order to check the chrominance signal-to-noise ratio when the test signal is a sinusoidal frequency sweep signal. The signal-to-noise ratio shall be measured on
40、the (R-Y) and (B-Y) output signals. 6.5 The cross colour S/N shall be calculated by means of the following formulae: NOTEThe filters HPF and LPF have the same characteristics template as shown in Figure 2.EN61041-2:1996 BSI 04-2000 5 7 Chrominance-to-luminance crosstalk 7.1 This measurement determin
41、es the degree of crosstalk of chrominance sidebands into the luminance channel, being demodulated as unwanted luminance signals. 7.2 The circuit arrangement shall be as shown in Figure 4. 7.3 The test signal (see Figure 4a) shall be a grey level(350mV) superimposed by a chrominance signal. This chro
42、minance signal during the active line period is composed of eight bars having the colours: cyan, red, cyan, red, blue, yellow, blue, yellow successively (see note). 7.4 After recording the test signal, the luminance signal shall be separated from the play-back composite signal by means of a low-pass
43、 filter and measured on an oscilloscope. The low-pass filter shall have a nominal cut-off frequency of2,8MHz(3dB). The colour subcarriers frequency shall be suppressed by46dB at4,25000MHz and at4,40625MHz. The reference level V refshall be the amplitude of the100% output picture signal(700mV) from b
44、lanking level to white level. The peak-to-peak amplitude of the unwanted luminance signals (V p-p ) (Figure 4b) superimposed on the50% grey level at the points of transitions between colour bars shall be measured and related to the reference V refin order to obtain the chrominance-to-luminance cross
45、talk CL by means of the following formula: 7.5 The value of CL in decibels shall be reported in the presentation of results. NOTEThe test signal is composed of eight bars whose colours correspond to those of the standard colour bars(100/0/75/0) defined in the CCIR Recommendation471-1. Such colours w
46、ere chosen in order to obtain the maximum frequency deviation, that is 280kHz and+230kHz in (R-Y) and (B-Y) respectively. 8 Chrominance-to-luminance displacement 8.1 This measurement determines the displacement of chrominance information with respect to the accompanying luminance information in the
47、output signal due to the separate processing of luminance signal and chrominance signal. 8.2 The circuit arrangement shall be as shown in Figure 5a. 8.3 The test signal shall consist of two parts as explained below: 1) In the first half of the active field period the test signal shall be a50% white
48、level superimposed by a chrominance signal. The chrominance signal is that of green and magenta colour corresponding to the green and magenta part of the100/0/33/0 colour bars (see Figure 5b and Figure 5c and Annex A). 2) In the second half of the active field period the test signal shall be a numbe
49、r of2T pulses having an amplitude of30% and superimposed on a black level according to Figure 5d. The number of2T pulses shall be equal to the number of transitions between green and magenta. 3) The timing of the2T pulses in relation to the timing of the transition between green and magenta bars shall be in accordance with Figure 5b, Figure 5c and Figure 5d. 8.4 Put theSW1 andSW2 switches in position2 (see Figure 5a) in order to measure the chrominance-to-luminance displacement of the video colour monitor itself. 8.5 Put theSW1 andSW
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