1、SMPTE 371 M-2002 SMPTE STANDARD for Television - 6.35-mm Type D-12 Component Format - Digital Recording at 1 O0 Mb/s 1080/60, 1080/50i, 720/60p Page 1 of 71 pages Table of contents 1 Scope 2 Normative references 3 Environment and test conditions 4 Tape 5 Helical recordings 6 Program track data 7 Aud
2、io processing 8 Video processing 9 Subcode processing 1 O Longitudinal tracks Annex A Tape tension Annex B Track pattern during insert editing Annex C Cross-tape track measurement technique Annex D Tape length and recording time Annex E . Abbreviations and acronyms Annex F Interface Annex G Bibliogr
3、aphy 1 Scope This standard specifies the content, format, and recording method of the data blocks containing video, audio, and associated data which form the helical records on 6.35-mm tape in cassettes as specified in SMPTE 307M. In addition, this standard specifies the content, format, and recordi
4、ng method for longitudinal cue and control tracks. One compressed video channel, eight independent audio channels and sub-code data are recorded on tape in the digital form. Each of these channels is capable of independent editing. The helical recordings are synchronized to on the following digital
5、video formats: - 1080-line/59.94-Hz field frequency - 1080-line/50-Hz field frequency - 720-line/59.94-Hz frame frequency Copyright 02oM by THE SOCIIY OF Approved August 7,2002 MOTION PICNRE AND TELEVISION ENGINEERS 595 W. Hartsdale Ave., White Plains. NY 10607 (914) 761-1100 SMPTE 371M-2002 These a
6、re hereafter referred to as the 1080/60i, 1080/50i, and 720/60p systems, respectively. Similarly, in this document, the 60-Hz system nomenclature refers to both 1080/60i and 720160 systems; whereas, the 50-Hz system refers only to the 1080/50i system. Nomenclature 1080-line system refers to both 108
7、0/60 and 1080/50i systems, while,the 720-line system refers only to the 720/60p system. The recorded digital video signal shall be compressed according to the DV-based 100-Mb/s specification. The recorded digital video signal, eight audio channels, and sub-code data shall be defined by the data stru
8、cture according to the DV-based lOO-Mb/s specification. 2 Normative references The following standard contains provisions which, through reference in this text, constitute provisions of the standard. At the time of publication, the edition indicated was valid. All standards are subject to revision,
9、and parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent edition of the standard indicated below. AES3-1992 (R1997), Serial Transmission Format for Two-Channel Linearly Represented Digital Audio Data ANSIBMPTE 276M-1995, Television -
10、Transmission of AES/EBU Digital Audio Signals Over Coaxial Cable SMPTE 12M-1999, Television, Audio and Film - Time and Control Code SMPTE 307M-2002, Television Digital Recording - 6.35-mm Type D-7 and Type D-12 Component Format - Tape Cassette SMPTE 321M-2002, Television - Data Stream Format for the
11、 Exchange of DV-Based Audio, Data and Compressed Video over a Serial Data Transport Interface SMPTE 37OM-2002, Television - Data Structure for DV-Based Audio, Data and Compressed Video at 100 Mb/s 1080/60i, 1080/50i, 720/60p 3 Environment and test conditions 3.1 Environment Tests and measurements ma
12、de on the system to check the requirements of this standard shall be carried out under the following conditions: - Temperature: 20C f 1C - Relative humidity: (50 5 2)% - Barometric pressure: From 86 kPa to 106 kPa - Tape conditioning: Not less than 24 h - Center tape tension: 0.09 N 0.02 N (see anne
13、x A) 3.2 Reference tape A blank tape for reference recordings shall be available from the format holder or approved source. 3.3 Calibration tapes The calibration tapes meeting the requirements of 3.3.1, 3.3.2, and clause 4 are available from manufacturers who produce digital television tape recorder
14、s and players in accordance with this standard. Page 2 of 71 pages SMPTE 371 M-2002 3.3.1 Record locations and dimensions All tolerances shown in table 1 or table 2 and clause 4.2 will be reduced by 50%. 3.3.2 Calibration signals Two sets of signals shall be recorded on the calibration tape: a) - Vi
15、deo: 1 O0 / O / 100 / O color bars compressed according to SMPTE 370M - Audio: 1 kHz tone at 20 dB below full scale on each audio channel - Cue: 1 kHz and 6 kHz tone at the analog recording reference level b) A signal of constant recorded frequency (Le., the Nyquist frequency) for the purpose of mec
16、hanical alignment. Recording level shall conform to 6.1.4.3 4 Tape 4.1 Base The base material shall be polyester or equivalent. 4.2 Width The tape width shall be 6.350 mm I 0.005 mm. The tape, covered with glass, is measured without tension at a minimum of five different positions along the tape usi
17、ng a calibrated comparator having an accuracy of 0.001 mm (1 pm). The tape width shall remain within the above specifications at any measuring position. 4.3 Width fluctuation Tape width fluctuation shall not exceed 5 pm peak-to-peak. Measurement of tape width fluctuation shall be taken over a tape l
18、ength of 900 mm. The tape width fluctuation shall be within the aforementioned specification at each of ten equally spaced points in the 900 mm span. 4.4 Reference edge straightness The maximum deviation of the reference edge straightness is 6 pm peak-to-peak. Edge straightness fluctuation is measur
19、ed at the edge of a moving tape guided by three guides having contact on the same edge and having a distance of 85 mm from the first to second guide and 85 mm from the second to third guide. Edge measurements are averaged over a 10 m length and are made 5 mm from the midpoint between the first and s
20、econd guide towards the first guide. 4.5 Tape thickness The total tape thickness shall be 8.8 pm + 0.0 pm - 0.8 pm and 6.7 pm + 0.0 pm - 0.4 pm. 4.6 Transmissivity Transmissivity shall be less than 5%, measured over the range of wavelengths 800 nm to 1000 nm. 4.7 Offset yield strength The offset yie
21、ld strength shall be greater than 3 N. The force to produce 0.2% elongation of a 1000-mm test sample with a pull rate of 10 mm per minute shall be used to confirm the offset yield strength. The line Page 3 of 71 pages SMPTE 371 M-2002 beginning at 0.2% elongation parallel to the initial tangential s
22、lope is drawn and then read at the point of intersection of the line and the stress-strain curve. 4.8 Magnetic coating The magnetic layer of the tape shall consist of a coating of metal particles or equivalent. 4.9 Coating coercivity The magnetic coating coercivity shall be a class 2300 (approximate
23、ly 2300 Oe / 184000 Ah), with an applied field of 10000 Oe / 800000 Alm measured by a vibrating sample magnetometer. 5 Helical recordings 5.1 Tape speed The tape speed shall be 1 35.2801 mm/s for the 60-Hz system and 135.41 54 mm/s for the 50-Hz system. The tolerance shall be * 0.2%. 5.2 Sectors Eac
24、h recorded track contains an IT1 sector, an audio sector, a video sector and a subcode sector. 5.3 Record location and dimensions The record location and dimensions for continuous recording shall be as specified in figures 1 and 2 and table 1 or table 2. In recording, sector locations on each helica
25、l track shall be contained within the tolerance specified in figure 1 and table 1 or table 2. The reference edge of the tape for dimensions specified in this standard shall be the lower edge as shown in figure 1. The magnetic coating, with the direction of tape travel as shown in figure 1, is on the
26、 side facing the observer. As indicated in figure 1, this standard anticipates a zero guard band between recorded tracks. The nominal record head width shall be equal to the track pitch of 18 pm. The scanner head configuration should be chosen such that the recorded track widths are contained within
27、 the limits of 16 pm to 20 prn. The format requires flying erasure for recording. In insert editing, this standard provides a guard band of 3 Fm f 1.5 prn between the previously recorded track and the inserted track at editing points only. A typical track pattern for insert editing is shown in figur
28、e B.1 of annex B. 5.4 Helical track record tolerance zones The lower edge of eight consecutive tracks starting at the first track in each frame shall be contained within the pattern of the eight tolerance zones established in figure 3. Each zone is defined by two parallel lines which are inclined at
29、 an angle of 9.1784 basic with respect to the tape reference edge. The centerlines of each zone shall be spaced apart 18.0 pm basic. The width of zone 2 shall be 3 pm and the width of zones 1, 3 to 8 shall be 5 pm. These zones are established to contain track angle errors, track straightness errors,
30、 and vertical head offset tolerance (the measuring technique is shown in annex C). Page 4 of 71 pages SMPTE 371M-2002 5.5 Relative positions of recorded information 5.5.1 Relative positions of longitudinal tracks Audio, video, control track and cue track with information intended to be time coincide
31、nt shall be positioned as shown in figures 1 and 2. 5.5.2 Program area reference point The program area reference point is determined by the intersection of a line parallel to the reference edge of the tape at a distance YO from the reference edge and the centerline of track O in each IT1 sector (se
32、e figures 1 and 2). The end of the preamble and beginning of SSA in the IT1 sector shall be recorded at the program area reference point, and the tolerance of dimension XO. The locations are shown in figures 1 and 2; dimensions XO and Yo are specified in tables 1 and 2. The relationship between sect
33、ors and contents of each sector is specified in clause 6. e Figure 1 - Location and dimensions of recorded tracks Page 5 of 71 pages SMPTE 371 M-2002 P2 cue, track fa, P1 Control Direction of track tapetravel )/- ZFnce Wavorrn i j Recorin current -1 i Magnetization on the tape Detail A Detail C Deta
34、il B Figure 2 - Location of recorded cue and control track Page 6 of 71 pages SMPTE 371 M-2002 Table 1 - Record location and dimensions for the 6 - 24-25 modulation; - Precoding. The program track data of IDO shall be processed through two operations as shown below: - Randomization; - Precoding. The
35、 preamble and postamble shall be 24-25 modulated by selecting pattern A or B according to the modulation rule in 6.1.3.2. The sync pattern shall not be processed through 24-25 modulation, but is selected from pattern F or G for audio and video sync blocks and pattern D or E for subcode sync block ac
36、cording to modulation rules in 6.1.3.2. Figure Il shows a possible block diagram of the process. 6.1.3.1 Randomization The data except sync patterns shall be randomized. The randomizing is equivalent to performing the exclusive-or operation between the input serial data and the serial data generated
37、 by the polynomial function below: x7+x3+ 1 where Xi are place-keeping variables in GF(2), the binary field. The first term is the most significant and the first to enter the division computation. The randomization is reset at IDO. The randomization limits the run length of the same binary value. Pa
38、ge 14 of 71 pages SMPTE 371 M-2002 bits 9nc API Syb,Panty recodin recoding PT Pre-codin Precodin recodin 1 ppd Pattern 1x2 1x14 I I I Precodin re-codin 77- Data sync Post-sync Audio block block Audio preamble post-amble Audio sync block Figure 8 - Modulation for audio sector Page 15 of 71 pages CMPT
39、E 371M-2002 Video preamble Randomi- Randomi- Lo; lLor 1 Pre-sync Data sync Post-sync Video sync block block block block post-amble 1 odulatio Pre-din recodin TT L 1 *+i odulatio cdulatio Pre-din re-codin Pre-codin TT? - LO?,+, Randomi- Randomi- 1 pR2:j odulatio Pre-codin Precodin pi Figure 9 - Modul
40、ation for video sector Page 16 of 71 pages SMPTE 371M-2002 .,.,. MSE LSB FR Res Res Res Arb Arb Arb Arb FR 4 . 25 ., 24 /I. d Arb Arb Arb Arb Syb, Syb2 Syb, Arb Sybl nr . 17 . Sync - Subcode preamble Cync pattem D or E - MSI LSE MSI Lse Data sync Subcode block post-amble bis Randomi- Randomi- Random
41、i- I mm modulation modulati n Pre-coding Preceding Pre-coding PPP Pattern Figure 10 - Modulation for subcode sector Page 17 of 71 pages SMPTE 371 M-2002 41 Input I DO Sync, preamble, and post-amble Recording amplifier I Figure 11 - Possible block diagram for signal processing Page 18 of 71 pages SMP
42、TE 371 M-2002 8 bits 6.1.3.2 24-25 modulation 8 bib 8 bits The 24-25 modulation is applied to the randomized data. An extra bit is inserted before the three consecutive randomized bytes as shown in figure 12. The modulated output, 25 bit data, is referred to as a codeword. The following criteria are
43、 used to insert the extra bit: 1111111 1111111 1) If the run length of Os or Is is ten or more, including the extra bit to be inserted at the junction, then the value of the extra bit shall be chosen so as not to make the run length any longer except in the case that the value of the bit in front an
44、d behind the junction is different and the run length is the same. 1111111 _-_ 2) If the run length is 9 or less, including the extra bit to be inserted at the junction, then the value of the extra bit shall be chosen to make the frequency characteristics of the pre-coded data nearer to the pilot si
45、gnal as shown in figures 13 and 14. 3 consecutive randomized bytes c =-l. 3) If the value of the bit in front and behind the junction are different and each run length is same, the value of the extra bit shall be chosen to make the frequency characteristics of the pre-coded data nearer to the pilot
46、signal as shown in figures 13 and 14. For the generation of the ATF signal, 24-25 modulation is applied to the data. The converted data satisfies the following conditions: - Track Fo: Attenuation of fl and f2 frequency components by at least 9 dB; - Track F1: Generation of f, component of at least 1
47、6 dB, but not more than 19 dB; - Track F2: Generation of f2 component of at least 16 dB, but not more than 19 dB. where fl = fb / 90 (Hz) f2 = fb / 60 (HZ) fb =The frequency whose period is a time interval of one channel bit(Hz) The modulated data are recorded on the tracks in the repeated cycle of
48、Fo - F1 - Fo - F2 sequence. Table 4 shows the relation between track and servo information. 6.1.3.3 Precoding The modulated bit stream shall be converted to interleaved NRZI as shown in figure 15. -I- codeword d- codeword _- codeword _-_ MSB LSB MSB LSB MSB LSB 1 -A -_- I 4 / Extia bit Figure 12 - B
49、it stream before interleaved NRZI modulation Page 19 of 71 pages CMPTE 371M-2002 Depth of notch: greater than 9 dB fl f, Frequency(Hz) (a) Track FO Pilot signal 1, CNR: reater than 16 dB and Depth of notch: greater than 3 dB ?esc than 19 dB Lev f, f, Frequency (Hz) (b) Track F1 Levy( Pilot sq CNR: reater than 16 dB and Depth of notch: greater than 3 dB !es than 19 dB f, Frequency(Hz) f, (c) Track F2 NOTES 1 fi=fb/QO(Hz) f, = fb / 60 (HZ) fb =The frequency whose period is a time interval of one channel bit(Hz) Resolution bandwidth =fd20925(Hz) Daia is obta
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