IEC 61904-2000 pdf free download – Video recording — Helical-scan digital component video cassette recording format using 12,65mm magnetic tape and incorporating data compression (Format digital-L).
|This International Standard applies to the format for video cassette recording of digitalcomponent video signals and associated digital audio signals and related control signals,using 12,65 mm magnetic tape.The video data are recorded using data compression.
This standard specifies characteristics of the cassettes, the tape, the recording patterns onthe tape, the processes of digital audio and video coding, data compression, error protectionand channel coding which are the essential requirements for interchangeability of recordings.
1.2 Normative references
The following normative documents contain provisions which，through reference in this text,constitute provisions of this International Standard. For dated references,subsequentamendments to,or revisions of， any of these publications do not apply.However，parties toagreements based on this International Standard are encouraged to investigate the possibilityof applying the most recent editions of the normative documents indicated below.For undatedreferences, the latest edition of the normative document referred to applies. Members of lECand lSO maintain registers of currently valid International Standards.
IEC60461:1986，Time and control code for video tape recorders
IEC 60958:1989,Digital audio interface
IEC 61213:1993,Analogue audio recording on video tape – Polarity of magnetization
IEC 61237-1:1994，Broadcast video tape recorders – Methods of measurement – Part 1:Mechanical measurements
ITU-R Recommendation BT.601-5:1995,Studio encoding parameters of digital television forstandard 4:3 and wide-screen 16:9 aspect ratios
ITU-R Recommendation BS.647-2:1992,A digital audio interface for broadcasting studios
ITU-R Recommendation BT.656-4:1998,Interfaces for digital component video signals in525-line and 625-line television systems operating at the 4:2:2 level of RecommendationTU-RBT.601 (Part A)
EBU Technical Recommendation R68:1995，Alignment level in digital audio productionequipment and in digital audio recorders
1.3 Abbreviations
For the purposes of this International Standard, the following abbreviations apply.
DCT: Discrete cosine transform
ECC: Error correcting code
TPS: Tracking pilot signal
TTS: Tracking timing signal
VLC: Variable length coding
1.4 Environment and test conditions
Tests and measurements made on the system to check the requirements of this standard
shall be carried out under the following conditions:
– temperature: 20 °C ± 1 °C;
– relative humidity: 50 % ± 2 %;
– barometric pressure: from 86 kPa to 1 06 kPa;
– tape tension: 0,3 N ± 0,05 N;
– tape conditioning: not less than 24 h.
1.5 Reference tape
Two kinds of blank tape may be purchased from the following manufacturer:
Sony Corporation
6-7-35 Kitashinagawa,
Shinagawa-ku, Tokyo, Japan
Product name Purpose
C2B-DB mechanical alignment
C2A-DB electrical alignment
1.6 Calibration tape
Manufacturers of video tape recorders designed for this format specification may sell calibration tapes meeting the following requirements. This information is given for convenience of users of this International Standard and does not constitute an endorsement by the IEC of the product named. Equivalent products may be used if they can be shown to lead to the same results.
1.6.1 Record locations and dimensions
Tolerance shown in table 2 should be reduced by 50 %.
2 Videotape cassette and tape
2.1 Mechanical parameters of cassette
2.1.1 Cassette dimensions
Two sizes of cassettes shall be identified as follows:
S cassette: 96 mm 1 56  mm 25 mm (as shown in figures 1 to 1 3)
L cassette: 1 45 mm 254 mm 25 mm (as shown in figures 1 4 to 26)
2.1 .2 Tape length and play time
The tape length and the play time are shown in table 1 as a reference only, and other combinations may be chosen.IEC 61904 pdf download.