1、BRITISH STANDARDBS EN 61146-4:1998Video cameras (PAL/SECAM/NTSC) Methods of measurement Part 4: Automatic functions of video cameras and camera-recordersThe European Standard EN 61146-4:1998 has the status of a British StandardICS 33.160.40g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54
2、g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN 61146-4:1998This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 December 2005 BSI 30 December 200
3、5ISBN 0 580 46237 4National forewordThis British Standard is the official English language version of EN 61146-4:1998. It is identical with IEC 61146-4:1998.The UK participation in its preparation was entrusted to Technical Committee EPL/100, Audio, video and multimedia systems and equipment, which
4、has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary.Cross-referencesThe British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section e
5、ntitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Complia
6、nce with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep UK interests informed; monitor related inter
7、national and European developments and promulgate them in the UK.Summary of pagesThis document comprises a front cover, an inside front cover, the EN title page, pages 2 to 21 and a back cover.The BSI copyright notice displayed in this document indicates when the document was last issued.Amendments
8、issued since publicationAmd. No. Date CommentsEUROPEAN STANDARD EN 61146-4NORME EUROPENNE EUROPISCHE NORM August 1998 ICS 33.160.40 Descriptors: Video equipment, motionpicture cameras, magnetoscope, characteristics, control functions, automatic, measurements, test results, testing condition, compari
9、son, mire, illuminance, luminance, colours English version Video cameras (PAL/SECAM/NTSC) - Methods of measurement Part 4: Automatic functions of video cameras and camera-recorders (IEC 61146-4:1998) Camras vido (PAL/SECAM/NTSC) Mthodes de mesure Partie 4: Fonctions automatiques des camras video et
10、des camscopes (CEI 61146-4:1998) Videokameras (PAL/SECAM/NTSC) Meverfahren Teil 4: Automatische Funktionen von Videokameras und Camcordern (IEC 61146-4:1998) This European Standard was approved by CENELEC on 1998-08-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations wh
11、ich 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 the Central Secretariat or to any CENELEC member. This Europea
12、n 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 the same status as the official versions. CENELEC members are the
13、 national electrotechnical committees of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. European Committee for Electrotechnical Standardization Comit Europ
14、en de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 1998 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 61146-4:1998 ECENELEC Foreword T
15、he text of document 100C/221/FDIS, future edition 1 of IEC 61146-4, prepared by SC 100C, Audio, video and multimedia subsystems and equipment, of IEC TC 100, Audio, video and multimedia systems and equipment, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61146-4 on
16、 1998-08-01. 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) 1999-05-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2001-05-
17、01 Annexes designated “normative“ are part of the body of the standard. In this standard, annexes A and ZA are normative. Annex ZA has been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 61146-4:1998 was approved by CENELEC as a European Standard without any modifi
18、cation. _ 2 EN 61146-4:1998 3 CONTENTS Page Clause 1 Scope . 5 2 Normative references 5 3 Terms and definitions 5 4 Conditions . 6 4.1 Environmental conditions . 6 4.2 Conditions of measurement 6 4.2.1 Illumination . 6 4.2.2 Shooting conditions. 6 4.2.3 Settings of the equipment under test . 6 4.2.4
19、 Reliability of measured results. 7 5 Method of measurement of automatic functions . 7 5.1 Automatic exposure control 7 5.1.1 Dependency on illumination level 7 5.1.2 Dependency on average brightness. 9 5.1.3 Dynamic response 12 5.2 Automatic focusing. 13 5.2.1 Assessment of focusing response time 1
20、3 5.2.2 Focusing accuracy 14 5.3 Automatic white balance. 15 5.3.1 Dependency on colour temperature of illumination. 15 5.3.2 Dynamic characteristics of automatic white balance. 18 Annex A (normative) Specification of the tracking chart 20Annex 2A (normative) Normative references to international pu
21、blications with their corresponding European publications . 21 Figure 1 Equipment arrangement for measurement of dependency on illumination level 8 Figure 2 Equipment arrangement for measurement of dependency on average brightness 10 Figure 3 Waveform of a horizontal line for B = 27 % 11 Figure 4 Wa
22、veform of a horizontal line for B = 77 %. 11 Figure 5 Waveform of a horizontal line for B = 9 %. 11 Figure 6 Typical response (1) . 12 Figure 7 Typical response (2) . 12 Figure 8 Equipment arrangement for measurement of focusing time 13 Figure 9 Equipment arrangement for measurement of automatic whi
23、te balance 16 Figure 10 Colour temperature conversion block and its specification . 17 Figure A.1 Dimensional specification of the large-sized tracking chart . 20 EN 61146-4:1998Page Table 1 Automatic exposure control Dependency on illumination level 9 Table 2 Automatic exposure control Dependency o
24、n average brightness 12 Table 3 Automatic focusing Assessment of focusing response time 14 Table 4 Automatic white balance Dependency on colour temperature of illumination. 18 Table 5 Optical filters used for conversion of colour temperature. 19 Table A.1 Positions of equi-centred small circles and
25、triangle markers 20 4 EN 61146-4:1998METHODS OF MEASUREMENT Part 4: Automatic functions of video cameras and camera-recorders 1 Scope This part of IEC 61146 applies to the assessment of characteristics of automatic functions which are implemented in colour video cameras and camera-recorders. The per
26、formance to be assessed in this standard is limited to automatic functions relating to light input from the lens and to the electronic output from video cameras and the video camera portions of camera-recorders. This standard defines test patterns, measurement conditions, methods of measurement and
27、the presentation of measured results so as to make possible the comparison of the measurement results. This standard intends to provide an objective method of measurement for each characteristic of the automatic functions but the results of objective measurements may not correlate well with the subj
28、ective assessment of automatic functions. It does not specify limiting values for the various characteristics related to automatic functions. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this part of IEC 6
29、1146. At the time of publication, the editions indicated were valid. All normative documents are subject to revision, and parties to agreements based on this part of IEC 61146 are encouraged to investigate the possibility of applying the most recent editions of the normative documents listed below.
30、Members of IEC and ISO maintain registers of currently valid International Standards. IEC 61146-1:1994, Video cameras (PAL/SECAM/NTSC) Methods of measurement Part 1: Non-broadcast single-sensor cameras ISO 8341:1989, Photography Slide projectors and filmstrip projectors Illumination test 3 Terms and
31、 definitions For the purpose of this part of IEC 61146, the following definitions apply. 3.1 grey scale chart test chart which has logarithmic grey steps of = 2,2 specified in item 1 of annex A of IEC 61146-1 5 EN 61146-4:1998 6 3.2 tracking chart test chart with a radial arrangement of black and wh
32、ite wedges (see annex A) 3.3 resolution chart test chart specified in item 4 of annex A of IEC 61146-1 3.4 uniform white chart test chart specified in item 2 of annex A of IEC 61146-1 3.5 equipment under test colour video camera and camera-recorder with electronic output(s) 4 Conditions 4.1 Environm
33、ental conditions All measurements shall be carried out within the environmental conditions as specified by the manufacturer. The environmental conditions during measurement, at least the temperature and the relative humidity, shall be reported together with the presentation of the measurement result
34、s. 4.2 Conditions of measurement 4.2.1 Illumination a) The illumination of test charts should be performed by two or four spot lights depending on the characteristics to be measured. b) The correlated colour temperature of the spot light shall be 3 100 K 100 K. c) Unless otherwise specified, the ill
35、umination level of the test chart shall be 2 000 lx 100 lx. d) The non-uniformity of the illumination shall be less than 5 %. e) The methods used for all the measurements shall be in line with the standard methods specified in ISO 8341. 4.2.2 Shooting conditions a) An optical axis of the equipment u
36、nder test shall coincide with a normal line of the test chart. b) Unless otherwise specified, the distance between the test chart and the equipment under test should be approximately 2 m. c) Unless otherwise specified, the zooming should be adjusted so that horizontal and vertical markers just fit t
37、he full frame of an under-scan monitor. 4.2.3 Settings of the equipment under test Except when otherwise indicated, the following setting shall be used: a) focus shall be adjusted for the best condition; EN 61146-4:1998b) white balance shall be adjusted automatically or manually for a correlated col
38、our temperature of 3 100 K 100 K; c) iris control of the lens may be automatic or manual; d) gain control may be automatic or manual. 4.2.4 Reliability of measured results The reliability and repeatability of measured results may be affected by the automation processes incorporated in the equipment
39、under measurement. Some automatic functions may exhibit instability. Therefore, averaging of data obtained by multiple measurement may be necessary if additional precision is required. 5 Method of measurement of automatic functions 5.1 Automatic exposure control 5.1.1 Dependency on illumination leve
40、l 5.1.1.1 Characteristics to be measured Dependency of absolute luminance signal levels and their relative deviation on illumination level. 5.1.1.2 Measurement conditions The measurements shall be conducted using the grey scale chart of = 2,2. The equipment arrangement shall be as shown in figure 1.
41、 7 EN 61146-4:1998EN 61146-4:1998 8 LampLampNeutral density filterEquipmentundertest10 000 lxTest chartOscilloscopeUnder-scan monitorTerminated by 75 Not terminatedIEC 724/98Figure 1 Equipment arrangement for measurement of dependency on illumination level 5.1.1.3 Method of measurement a) The test c
42、hart illuminated with 10 000 lx by lamps having a correlated colour temperature of 3 100 K 100 K shall be imaged to fill the full screen. b) The luminance signal level Y (corresponding to a white part at the centre of the test chart) relative to the blanking level shall be measured with an oscillosc
43、ope. The measurements shall be conducted with the following densities D of neutral density optical filters placed in front of the lens: D = 0,0 (effective illumination of 10 000 lx); D = 0,7 (effective illumination of 2 000 lx); D = 1,4 (effective illumination of 400 lx); D = 2,1 (effective illumina
44、tion of 80 lx). c) The measured results are noted as Y10 000, Y2 000, Y400and Y80. d) The dependency of luminance signal level on the illumination level shall be calculated by the following equation: RYYnn=2 0001 100 % where n = 10 000, 400 and 80. 5.1.1.4 Presentation of results The absolute lumina
45、nce signal levels and their relative deviations shall be reported as in table 1. Table 1 Automatic exposure control Dependency on illumination level 10 000 lx 2 000 lx 400 lx 80 lx Absolute level (mV) Y10 000Y2 000Y400Y80Relative deviation (%) R10 0000 R400R80NOTE Measured results will not directly
46、relate to a practical automatic function. The result should be understood as showing a tendency of the equipment under test. 5.1.2 Dependency on average brightness 5.1.2.1 Characteristics to be measured Luminance signal level and its relative deviation as a function of average brightness of shooting
47、 target. 5.1.2.2 Conditions of measurement The equipment arrangement shall be as shown in figure 2 with the grey scale chart having = 2,2. The test chart surrounded by a white or black background shall be illuminated to give the standard illumination condition specified in 4.2.1. The white board sha
48、ll have a reflectance of 83 % 3 %, and the black background shall have a reflectance of less than 5 %. 9 EN 61146-4:1998 10 LampLampTest chart withreflecting boardsEquipmentundertestWhite or black boardsGrey scale chartTerminated by 75 Not terminatedOscilloscopeUnder-scan monitorIEC 725/98Figure 2 E
49、quipment arrangement for measurement of dependency on average brightness 5.1.2.3 Method of measurement a) The grey scale test chart shall be imaged to fill the full screen and the luminance signal level V5,corresponding to the fifth step of the chart (see figure 3) shall be measured using an oscilloscope. The measured result which corresponds to average brightness B = 27 % is noted as Y27. EN 61146-4:1998V10V51 H
