IEC 62122 pdf download – Methods of measurement for consumer-use digital VTRs – Electronic and mechanical performances

admin
IEC 62122 pdf download – Methods of measurement for consumer-use digital VTRs – Electronic and mechanical performances

IEC 62122 pdf download – Methods of measurement for consumer-use digital VTRs – Electronic and mechanical performances
This standard specifies the basic methods of measurement for evaluating the electronic andmechanical performances of consumer-use digital VTRs.
The formats of open reel VTRs,Beta,VHS, and 8 mm VTRs have been standardized.Methods ofmeasurement for these analogue VTRs have been standardized in IEC 61041-1,IEC 61041-2,IEC 61041-3,IEC 61041-4,IEC 61041-5,and EC 61146-3. Digital VTR 6,35 mm DV formatand 12,65 mm D-VHS format have now been brought on the market. The methods ofmeasurement for these consumer-use digital VTRs should be specified and standardized.
With these measurement techniques,some items for the evaluation of performances specificto digital VTRs have also been included.
There are two objectives for the proposed methods of measurement.One is to check theinterchangeability and characteristics of the equipment under test which are indispensable tomanufacturers,and the other is to evaluate the quality of image and sound,which concernsthe customer.The latter is a priority for consumer satisfaction.
Since a consumer can use only general-purpose instruments, any test which needs dismantlingof apparatus and requires special instruments is in principle not specified.As error rate isimportant for digital equipment, an example of a method for measuring error rate is given inannex A.
2Normative references
The following referenced documents are indispensable for the application of this document.Fordated references,only the edition cited applies. For undated references,the latest edition ofthe referenced document (including any amendments) applies.
IEC 60094-3:1979, Magnetic tape sound recording and reproducing systems – Part 3: Methodsof measuring the characteristics of recording and reproducing equipment for sound onmagnetic tape
lEC 60386:1972,Method of measurement of speed fluctuations in sound recording andreproducing equipment
IEC 60883:1987,Measuring method for chrominance signal-to-random noise ratio for videotape recorders
IEC 61041-1:1990,Non-broadcast video tape recorders – Methods of measurement – Part 1:eneral, video (NTSC/PAL) and audio (longitudinal) characteristics
IEC 61041-5:1997,Non-broadcast video tape recorders – Methods of measurement – Part 5:High-band video tape recorders including those equipped with Y/C video connectors(NTSC/PAL)
IEC 61834 (all parts),Recording – Helical-scan digital video cassette recording system using6,35 mm magnetic tape for consumer use (525-60,625-50,1125-60 and 1250-50 systems)ITU-R BT.471-1:1986,Nomenclature and description of colour bar signals
ITU-R BT.500-10:2000,Methodology for the subjective assessment of the quality of televisionpictures
ITU-R BT.1204:1995,Measuring methods for digital video equipment with analogue input/output
3Terms and definitions
For the purposes of this International Standard, the following terms and definitions apply.
3.1
consumer-use digital VTR
consumer-use video tape recorder using digital recording technology,6,35 mm to 12,65 mmwidth videotape and bandwidth compression technology for the image signal. Two tape formatsare standardized, as defined in the following two definitions.Although different formats may beintroduced in the future, fundamental measuring methods can be adapted to all formats
3.1.1
DV format
6,35 mm helical-scan vTR standardized in lEC 61834
3.1.2
D-VHS format
12,65 mm helical-scan VTR which will be standardized in the near future.Until then,refer tothe outline of the D-VHS format in documents [1]1 and [2]
3.2
ferrofluid development
direct observation of the magnetization on the videotape by the adherence of iron powder to itssurface by dipping the tape into a fluid containing powder of fine iron in order to observe therecorded pattern using a microscope
3.3
byte
unit which separates the information series 1 into m bits. m usually consists of 8 bits, but notalways
3.4
error rate
ratio of the number of erroneous elements to the total number of elements reproduced and/ortransmitted during a given time interval
NOTE 1 The elements may be, for example, digits, code words or blocks.NOTE 2 “Error ratio” is dafined in similar terms as in lEv 704-18-03.
3.5
byte error rate
error rate for a signal constructed from byte units
(number of erroneous byte units)/(total number of elements of byte units)
3.6
MPEG-2 transport streamMPEG-2 TS
data transmission format standardized by ISO/IEC MPEG (Moving Picture image codingExperts Group)
3.7
three dimensional(3D) signal processing
TV video signal process taken from three viewpoints: the horizontal and vertical directions andthe time domain.Generally, it contains the operation processing between the fields or betweenframes using a field memory or a frame memory