WO1992009073A1 - Device for recording digital picture signal - Google Patents

Device for recording digital picture signal Download PDF

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Publication number
WO1992009073A1
WO1992009073A1 PCT/JP1991/000755 JP9100755W WO9209073A1 WO 1992009073 A1 WO1992009073 A1 WO 1992009073A1 JP 9100755 W JP9100755 W JP 9100755W WO 9209073 A1 WO9209073 A1 WO 9209073A1
Authority
WO
WIPO (PCT)
Prior art keywords
circuit
data
magnetic
signal
di digital
Prior art date
Application number
PCT/JP1991/000755
Other languages
French (fr)
Japanese (ja)
Inventor
Keiji Kanota
Hajime Inoue
Akihiro Uetake
Moriyuki Kawaguchi
Yukio Kubota
Kazunobu Chiba
Original Assignee
Sony Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to JP2307508A priority Critical patent/JPH04179380A/en
Priority to JP2/307508 priority
Application filed by Sony Corporation filed Critical Sony Corporation
Priority claimed from US08/768,871 external-priority patent/US5384666A/en
Publication of WO1992009073A1 publication Critical patent/WO1992009073A1/en
Priority claimed from US08/219,957 external-priority patent/US5512349A/en

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Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00Details of colour television systems
    • H04N9/79Processing of colour television signals in connection with recording
    • H04N9/80Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback
    • H04N9/804Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback involving pulse code modulation of the colour picture signal components
    • H04N9/8042Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback involving pulse code modulation of the colour picture signal components involving data reduction
    • H04N9/8047Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback involving pulse code modulation of the colour picture signal components involving data reduction using transform coding
    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/008Recording on, or reproducing or erasing from, magnetic tapes, sheets, e.g. cards, or wires
    • G11B5/00813Recording on, or reproducing or erasing from, magnetic tapes, sheets, e.g. cards, or wires magnetic tapes
    • G11B5/00847Recording on, or reproducing or erasing from, magnetic tapes, sheets, e.g. cards, or wires magnetic tapes on transverse tracks
    • G11B5/0086Recording on, or reproducing or erasing from, magnetic tapes, sheets, e.g. cards, or wires magnetic tapes on transverse tracks using cyclically driven heads providing segmented tracks
    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/02Recording, reproducing, or erasing methods; Read, write or erase circuits therefor
    • G11B5/09Digital recording

Abstract

A device for recording digital picture signals has a circuit for converting the input digital picture signals into blocks of data comprising a plurality of picture element data, an encoding circuit which encodes the output of the converting circuit in compressed data for every block, and a channel-encoding circuit which channel-encodes the encoded data outputted from the encoding circuit. The data outputted from the channel-encoding circuit is recorded on a magnetic tape by magnetic heads installed on a rotating drum. In the device, the pitch of the tracks formed on the magnetic tape by the magnetic heads is 5.5 νm or less, the diameter of the rotating drum is 25 mm or less, and the track length per unit time is made to be a predetermined one by setting the rotating speed of the rotating drum at 150 rps or more. Thereby, long recording time is possible by a mechanism part of a small size and further, the error relative to the linearity of the track can be reduced.

Description

Specification

The title of the invention

The magnetic recording apparatus of the di digital image signal

Technical field

This invention relates to apparatus for recording on a magnetic tape di digital image signals, such as di digital video signals, in particular, by selecting the Ajimasu angle head to the magnetic to a predetermined one, for long time recording and related to the magnetic recording apparatus of the di digital image signal

BACKGROUND

Recently, as the di digital VTR for recording on a recording medium such as a magnetic tape by de-digitizing a color video signal, Konboji' preparative shaped Di digital VTR and D 2 Fomatsu capital of component type D 1 Fomatsu bets for broadcasting stations di digital VTR of has been put to practical use.

The former D 1 format di digital VTR of the luminance signal and the first and second color difference signals respectively 1 3. 5 MHz, 6. 7 5 M predetermined signal processing after AZD converted by sampling frequency of Hz used to record on the tape carried out, the ratio of the sampling frequencies of these components components 4: 2: 2 is at or al, 4: 2: 2 format and is also referred to.

The latter D 2 full Omatsu preparative di digital VTR of the Composite Tokara one video signal by performing sampling at four times the frequency of the signal of the frequency f sc of the color subcarrier signal and AZD conversion, a predetermined signal processing after, and to record on the magnetic tape.

These di digital VTR, because they are designed on the assumption that you are used together for broadcast stations, is the image quality priority, in one sample, for example, 8 bits of AZD converted de Jitaruka La one video signal without substantially compressed, and I record Unishi.

- As an example, a description will be given of a data amount of di digital VTR of the former D 1 Fomatsu bets.

Information of the color video signal is a sampling frequency described above, when AZD converted by the Samburu per 8 bits, the information amount of about 2 1 6 M ps (megabit Z seconds). Among Excluding the data of horizontal and vertical blanking period, 1 number of effective pixels 7 2 0 of the luminance signal of the horizontal period, number of effective pixels 3 6 0 of the color difference signal, is the number of effective scanning lines for each field because the NTS C system (5 2 5 Z 6 0) in 2 5 0, the data amount D v of the video signal per second

DV = (720 + 360 +360) X 8 x 250 x 60

= 172.8 Mb ps

To become.

In the PAL system (6 2 5Z5 0) Any Fi number of effective scanning lines for each one field is 3 0 0, considering that the number of fields per second is 5 0, Then, the amount of data is equal to the NTS C system Naruko and is found. When considering the redundant components for error correction and formatting of these data, bit Torre one bets 呋像 de Isseki of about 2 0 5. 8 Mb ps in total. The audio 'data D a is Ri be about 1 2. 8 Mb ps, further gears-up for editing, a preamble, since the additional data D 0, such as post Toanpuru of about 6. 6 Mb ps, recording de total information amount D t Isseki is as follows.

D t = D v + D a + D o

= 172.8 + 12.8+ 6.6 = 192.2 M bps

For recording data having the amount of information, the de-digital VTR of D 1 full Oma Tsu DOO, as the track pattern, also 1 0 track, one field in the NTSC system, segments using one two tracks in the PAL scheme method has been adopted.

Also be used. For 1 9 顏幅 as recording tape, the tape thickness There are two types of 1 3 / m and 1 6〃M large the cassette for accommodating this (L), Medium ( M), 3 kinds of things are prepared in small (S). Due to the recording information data in full Oma' bets described above these tapes has a ¾ 2 0. 4 i ΐ about as the data recording density. When recording density is high, the waveform degradation due to nonlinearity of the electromagnetic conversion system of the intersymbol interference Aruiwae' de tape, tends error of the reproduction output data is generated. The conventional recording density, even doing error correction coding, numerical values ​​described above was limited.

Together, these parameters Isseki, D 1 format cassette Bok of playback time of each size of Di digital VTR of is as follows. Size z tape thickness 1 3 thickness 1 6 m thickness s 1 3 min 1 1 min

M 4 2 minutes 3 4 minutes

As VTR of L 9 4 min 7 6 min Thus D 1 format di di evening Le VTR broadcasters, although as determined the performance of the image quality priority is of sufficient, 1 9 mm width be used cassettes large equipped with tape having, at most 1. not obtained either Shi reproduction time of about 5 hours, for use as a VTR for home use, it can be said that extremely unsuitable person. To improve the recording density, it is effective to the track Kupitchi small. However, the conventional VT R, when the track pitch is small, yea good linearity of tracks, the tracking error or the like, the error in the reproduced data is increased, there is a limit in terms of the track pitch and the small and t particularly, compatibility between VTR devices had depleted signal problem.

- How, as the current home VTR, ^ method, VHS system, neither is 8 mm system, etc. have been put into practical use and performs recording and reproduction in the form status of the analog signal, the image quality of each is significantly improved and that - although, for example, when trying to copy the dub what was recorded by imaging by the camera, kana Rino image degradation occurs at the stage of this dubbing, if this was repeated several times, mined there is a disadvantage that becomes unbearable to command appreciation. Disclosure of the Invention

Accordingly, an object of this invention is a good linearity of the track, the tracking error difficulty rather occur, therefore, in providing Hisage recording apparatus Di digital surface image signal capable of a track pitch and a small is there.

Another object of the invention, be repeated a plurality of times of dubbing, Mel to _ and to provide a recording apparatus of smaller di digital image signal image degradation o

The present invention, blocks of circuit for converting the data input di digital image signal comprising a plurality of pixel data blocks Unit

And (5, 6), a coding circuit (8) for compressing and encoding the blanking lock unit the output data of the blocking circuit (5, 6), encoding circuitry the output encoded data of (8) Cha tea down channel coding includes a circuit (1 1) and the channel coding circuit for tunnel encoding

(1 1) output data to the magnetic mounted on the rotary drum (7 6) of head (1 3 A, 1 3 B) of di digital image signal to be recorded on the magnetic tape (7 8) by and have you in the magnetic recording device, a magnetic tape by head to the magnetic (1 3 a, 1 3 B)

(7 8) the pitch of tracks formed on 5. 5〃M follows no, select the diameter of the rotary drum (7 6) under 2 5 聽以, 1 the rotational speed of the rotating drum (7 6) the 5 0 rps or more and Nasukoto is the track length per unit time in the magnetic recording apparatus of the di digital image signal to Toku徵 that it has a predetermined one. Improvement of linearity of the track, since the reduction of the tracking error can be achievement, without involvement of moths one Doban de on the magnetic tape 7 8, also natural, can form a track with a narrow track pitch, the long-time recording is It can become.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is block diagram showing the structure of a recording side of the signal processing unit in the embodiment of the present invention, FIG. 2 is a block diagram showing a configuration of a reproducing side of the signal processing unit, Figure 3 is block coding schematic diagram showing an example of a pro click for, FIG. 4 is schematic diagram used for explaining the Sabusanpuri ring and support brine, FIG. 5 is a block diagram of an example of a block encoding circuits, Figure 6 Tsu is proc diagram showing an outline of an example of a channel encoder, proc diagram showing an outline of an example of FIG. 7 is a channel decoder, schematic diagram used for explaining a head arrangement to FIG. 8 is the Figure 9 is schematic diagram used for explaining the azimuth of de, schematic diagram first 0 Figure used for explaining a recording pattern, the first 1 Figure is a top view and a side view showing an example of a head system to the tape, the first 2 Figure stands for order to explain the vibration of the tape occurs in the eccentricity of the drum Fig first 3 Figure schematic diagram Ru employed in the description of the magnetic tape manufacturing method, the first 4 figures are a perspective view showing an example of the structure of the head to the magnetic.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, a description will be given of an embodiment of the present invention. This description is made in the following order.

a. The signal processing unit

b. Proc coded C. Cha emission channel encoder and tea N'nerudekoda

d. heads. tape system

e. electromagnetic conversion system

a. The signal processing unit

First, a description will be given to the signal processing section of the di digital VTR in this embodiment.

Figure 1 is illustrates as a whole structure of the recording side. 1 Y, 1 U, 1 V, in the three primary color signals R from the input terminal each indicating for example, a color video camera, G, Di digital Brightness signal Y formed from B, di digital color difference signals U, V are supplied that. In this case, the clock rate of each signal is the same as the frequency of each component signal of the D 1 Fomatsu bets described above. That is, sampling frequency 1 3. 5 MHz each. 6. is a 7 5 MHz, which and is number of bits per sample of these 8 bits.従Tsu Te ', the input terminals 1 Y, 1 U, as the data quantity of the signal supplied to IV, as described above, is about 2 1 6 Mb ps. The data blanking period removed out of the signals, the data amount is compressed to about 1 6 7 Mb ps only by the taking out effective information extraction circuit 2 information of the effective area. Effective luminance signal Y among the output of the information extraction circuits 2 are supplied to a frequency conversion circuit 3, sampling frequency Ru is converted to 3/4 from 1 3. 5 MHz. As the frequency converting circuit 3, for example, decimation filter is used, are adapted to aliasing distortion. No. The output signal of the frequency conversion circuit 3 is supplied to a plot click circuit 5, the order of the luminance data is converted into the order of the blocks. Block circuit 5 is provided for the proc encoding circuit 8 disposed downstream.

Figure 3 shows the structure of a proc units of coding. This example is a three-dimensional block, for example by dividing the straddle plane surfaces two frames, as shown in FIG. 3, the unit block is formed in a large number of (4 lines X 4 pixel X 2 frame) It is. In FIG. 3, the solid line indicates a line of an odd field, dashed lines indicate the lines of the even field.

Further, among the outputs of the effective information extraction circuit 2, the two color difference signals U, V are supplied to Sabusanpuri ring and subline circuit 4, after the sampling frequency is converted to a half from each 6. 7 5 M Hz, two di digital color difference signals are selected line by line alternately, are combined into one channel of data. Therefore, Di digital and color difference signals which are successively of the line from this Sabusanpuri ring and subline circuit 4 is obtained. The pixel configuration of the sub sample and sub-line of the signal by the circuit 4 shown in FIG. 4. In Figure 4, 〇 indicates sampled in g pixels of the first color difference signal U, △ denotes a sampled pixel of the second color difference signal V, X is shows the positions of the pixels decimated by the subsampling be o

Sabusanpuri line sequential output signal of the ring and the sub-line circuit 4 is supplied to the proc circuit 6. Similar to the block circuit 5 in plots click circuit 6, the color difference data of the order of scanning of the television job tone signal is converted into data of the order of blocks. The Bed α click circuit 6, like the plot click circuit 5, converts the evening chrominance data into block structure of (4 lines X 4 pixel X 2 frames). The output signal of the block circuit 5 and 6 is fed subjected to the synthesizing circuit 7.

The combining circuit 7, the luminance signal 及 beauty chrominance signal converted into the order of blocks are converted into data of one channel, the output signal of the combining circuit 7 is supplied to the plot click encoding circuit 8. As the pro click encoding circuit 8, (referred to as ADRC) encoding circuit adapted to da Inami click range for each block as will be described later, DCT (Discrete Cosine Transform) circuit or the like can be applied. The output signal of block encoding circuit 8 is supplied to a framing circuit 9 and converted into data of a frame structure. In the framing circuit 9, instead riding the clock of the clock and the recording system of the image system is performed.

The output signal of the framing circuit 9 is supplied to a parity generating circuit 1 0 error correction code parity of error correction code is generated. The output signal of the parity generating circuit 1 0 is supplied to the tea N'neruen coder 1 1, tea N'nerukodi ring such as to decrease the low frequency portion of recording data is performed. The output signal of the tea N'neruen coder 1 1 is subjected fed to the magnetic heads 1 3 A, 1 3 B via the recording amplifier 1 2 A, 1 2 B and the rotary preparative lance (not shown), recorded on the magnetic tape It is.

The audio signal is also not shown, the video signal is separately compressed and encoded, is supplied to the tea down channel encoder.

The signal processing described above, the data amount 2 1 6 Mb ps input is reduced to about 1 6 7 Mb ps by extracting only the effective scanning period, further frequency conversion and sub-sample by a sub-line, which is 8 4 M It is reduced to bps. This data by compression coding by plotting click encoding circuit 8, is compressed to about 2 5 bs, added subsequent parity, additional information such as audio signals, the recording data of 3 1 . on the order of 5 6 M bps.

It will now be described with reference to Figure 2 the structure of the reproducing side. Play de one evening from the magnetic heads 1 3 A, 1 3 B is supplied to a channel decoder 2 2 via a rotary transformer (not shown) and playback amplifier 2 1 A, 2 1 B in the second view. In channel Rudekoda 2 2, the demodulation of the channel-coded ring, the output signal of the channel decoder 2 2 is Kyo耠 the TBC circuit (time between base corrector) 2 3. And it has the signature 8_Rei circuit 2 3 Nio, time base fluctuation component of the reproduced signal is removed. Reproducing data from the TBC circuit 2 3 are supplied to the ECC circuit 2 4, and the error correction and error modification using error one correction code is performed. 0 the output signal of the ECC circuit 2 4 Ru is supplied to a frame separation circuit 2 5

The deframing circuit 2 5, together with other components of the block code Cadet Isseki are respectively separated, transfer of the image system clock is made from the recording system clock. Each data separated by the frame separation circuit 2 5 is supplied to the proc decoding circuit 2 6, restoring data corresponding to the original data in each block is decoded. Decoded data is supplied to the distribution circuit 2 7. In this distribution circuit 2 7, the decoded data is separated into a luminance signal and color difference signals. Luminance signal and color difference signals are respectively supplied to the plot click separation circuit 2 8 and 2 9. Block separation circuit 2 8 and 2 9, the plot click circuit 5 and 6 opposite the transmission side, converts the decoded data of the order of blocks in the order of raster scanning.

Decoded luminance signal from the plot click separation circuit 2 8 interpolation fill evening

It is supplied to the 3 0. In the interpolation filter 3 0, San pre Ngure preparative luminance signal is converted from 3 fs 4 to fs (4 fs = 1 3. 5 MHz). Di digital luminance signal Y from the interpolation filter 3 0 are obtained from an output terminal 3 3 Y.

- How, di digital color difference signals from the block separation circuit 2 9 is supplied to a distribution circuit 3 1, line sequence has been de-di Yuru color Sashin No. U, V are each separated into di digital color difference signals U and V that. Di digital color difference signals U from the distribution circuit 3 1, V is supplied to the interpolation circuit 3 2, they are respectively interpolated. Interpolation circuit 3 2 is intended to interpolate the data of decimated lines and pixels using the restored pixel data from the interpolation circuit 3 2, sampling Ngure bets is 4 fs di digital color difference signals U and V It is obtained, respectively taken out to the output terminal 3 3 U, 3 3 V.

b. block coding

The plot click coding circuit 8 in FIG. 1 described above, Japanese Patent Application No. Sho present applicant previously filed 5 9 - 2 6 6 4 0 7 No. and No. Sho 5 9 - 2 6 9 8 6 6 No. AD RC (Adaptive Dynamic Range Coding) encoder shown in the like can be used. The AD RC encoder detects a maximum value MAX and the minimum value MIN of a plurality of pixel data contained in each block, detects a dynamic range DR of the proc from these maximum values ​​MA X and the minimum value MIN, the dynamic range It performs encoding adapted to the DR, and performs re-quantized by a small number of bits than the number of bits of the original pixel data. Other examples of proc coding circuit 8, after the DCT the surface elements data of each block (Di screte Cosine Transform), the coefficient data obtained by the DCT and quantization, run-length Huffman quantized data it may be used a configuration in which compressed and encoded with encoding.

Here, using the ADRC encoder, further also surface quality deteriorates when the multi-dubbing is an example of an encoder with reference to FIG. 5 will be described which does not occur.

In FIG. 5, 4 1 Di digital example one sample input terminal shown is quantized to 8 bits in the video signal (or de I digital color difference signal) is input from the combining circuit 7 of FIG. 1. Maximum block data from the input terminal 4 1 is Kyo耠 to the minimum value detection circuit 4 3 and the delay circuit 4 4. Maximum value, the minimum value detecting circuit 4 3, the minimum value MIN, detects a maximum value MAX for each block. From the delay circuit 4 4, the time required for the maximum and minimum values ​​are detected, delays the input data. Test pixel data from the delay circuit 4 4 to the comparison circuit 4 5 and the comparison circuit 4 6

^ It is.

Maximum value, the maximum value MAX from the minimum value detecting circuit 4 3 is supplied to the subtracting circuits 4 7, the minimum value MIN Ru is supplied to the adding circuit 4 8. These subtraction circuit 4 7 and the adding circuit 4 8, 1 quantization step width in the case of the Roh down edge pine quenching amount Coca from bit tosylate oice circuit 4 9 4-bit fixed-length value (厶 = 1/1 6 DR) is supplied. Bit Toshifu DOO circuit 4 9 is a division to perform, to 4 bits tosylate oice a dynamic Kurenji DR configuration of (1 Bruno 1 6). From the subtraction circuit 4 7, (MAX - △) threshold is obtained, and from the adding circuit 4-8 is obtained threshold (MIN + △). Threshold from these subtraction circuit 4 7 and the summing circuit 4 8 are respectively subjected feeding the comparator 4 5 and 4 6.

Note that this value defines the threshold △ is not limited to the quantization step width may be a fixed value corresponding to the noise level. The output signal of the comparator circuit 4 5 is supplied to the AND gate 5 0, the output signal of the comparator circuit 4 6 is supplied to the AND gate 5 1. The AND gate 5 0 and 5 1, Isseki input data from the delay circuit 4 4 is supplied. The output signal of the comparator circuit 4 5 becomes a high level when the input data is greater than the threshold, therefore, the output terminal of the AN D gate 5 0, included in the maximum level range of (MAX~MAX- △) input data of pixel data is Ru are extracted. The output signal of the comparator circuit 4 6 becomes a high level when input data Isseki is smaller than the threshold, therefore, the output terminal of the AND gate 5 1, the minimum (Μ Ι Ν~Μ Ι Ν + Δ) pixel data of the input data contained in the level range is extracted.

Attitude signal of the AND gate 5 0 is supplied to the averaging circuit 5 2, the output signal of the AND gate 5 1 is supplied to an averaging circuit 5 3. These averaging circuit 5 2 and 5 3, and calculates an average value for each block, reset signals of block period is supplied to the averaging circuit 5 2 and 5 3 to the terminal 5 4. From the averaging circuit 5 2, (MAX~MAX- △) maximum average value MAX of the pixel data belonging to level range 'is obtained, the averaging circuit 5 3 or colleagues, the (MIN~MIN + 厶) the average value of the image element data belonging to the minimum level range MIN 'are obtained. Is subtracted by the subtraction circuit 5 5 'average value MIN from' average MAX, the subtraction circuit 5 Five et dynamic range DR 'is obtained.

The average value MIN 'is supplied to the subtraction circuit 5 6, the delay circuits 5 7 from the input data through the average value MIN' is subtracted in the subtraction circuits 5 6, data PD 1 after minimum removal There is made form. The Deda PD 1 and retouching has been dynamic Kkure Nji DR 'is supplied to the quantization circuit 5 8. In this embodiment, (not transmitted code signal) number of bits n is 0 bit assigned to the quantization, 1 bit, 2 bits, 3 bits, variable length that is one of 4 bits a ADR C, edge matching quantization is performed. Assign bit number n is determined in the bit number deciding circuit 5 9 for each block, Isseki de bits number n is Kyo耠 the quantization circuit 5 8.

Variable-length ADRC is 'the small block is allocated bits preparative number n less, dynamic range DR' dynamic range DR in the large proc, by increasing the allocation bit number n, efficient code reduction can be carried out. Immediately Chi, the threshold of the T 1~T 4 (Τ 1 rather T 2 rather T 3 ° .tau.4) in determining the number of bits n, block of (DR 'Ku T 1), the code signal There is not transmitted, only the dynamic range DR one information is transmitted, (T 1 ≤DR <T 2) blocks is a (n = l), a block of (T 2≤DR 'Ku T 3) is , and (n = 2) is a, (T 3≤DR 'Ku T 4) blocks of, (n = 3) is a, (DR' block of ≥ T 4) is, (n = 4) It is.

In the this changing such length threshold T 1 to T 4 in ADRC, can be controlled amount of information generated (so-called buffer-ring) is. Accordingly, one field or a variable-length A DR C even for a transmission path such as di digital VTR of this invention can be the amount of generated information per one frame to a predetermined value is required can be applied.

The In Figure 5, 6 0 indicates buffer-ring circuit for determining the threshold value T 1 to T 4 for the amount of generated information to a predetermined value, the Baffua-rings circuit 6 0, the threshold set (T l, Τ 2, Τ 3, Τ 4) are prepared a plurality of, for example 3 2 sets, sets of these thresholds parameters Isseki code P i (i = 0, 1, 2, · • It is distinguished by 3 1). Roh,. According to the numbering i size Kunar shimmer Isseki code P i, the amount of generated information is to decrease monotonously, are set. However, as the amount of generated information decreases, the picture quality of the restored image is degraded.

Roh Ffa threshold T 1 to T 4 from-ring circuit 6 0 is supplied to the comparator circuit 61, dynamic received through the delay circuit 6 2 click range DR 'is supplied to the comparison circuit 6 1. . The delay circuit 6 2, the time required to set the threshold value is determined by Roh Ffa-ring 6 0 delays the DR '. In the comparison circuit 61, a dynamic range DR 'of the block and the threshold are compared, respectively, the comparison output is supplied to the bit number determining circuit 5 9, allocation bit number n of the block is determined . The quantization circuit 5 8, dynamic Kurenji DR 'and the allocation bit number n and the data PDI after the minimum value removing that through the delay circuit 6 3 using the by quantization of Etsu di matching code signal DT It is converted to. Quantization circuit 5 8 is composed of, for example, ROM.

The delay circuit 6 2 and 6 4 respectively through and gets been dynamic Kurenji DR ', the average value MIN' are output, parameter one Tako de P i is of output showing still set of code signal DT and the threshold It is. In this example, once based on Roh down edge matching quantized signal a new dynamic range information, face image deterioration when the dubbed because it is the edge matching quantization is assumed small.

c. tea down channel encoder and tea N'nerudekoda

Then channel encoder 1 1 of FIG. 1 and Chiyan'nerude coder 2 2 will be described. For more information about these circuits, but the specific configuration in Japanese Patent Application No. 1 one 1 4 3 4 9 No. 1 the present applicant has filed is disclosed, with reference to FIGS. 6 and 7 for the schematic structure It described Te.

In Figure 6, 7 1, adaptive scrambling circuit which the output of the parity generating circuit 1 0 of FIG. 1 is supplied, the scrambling circuit of the plurality of M-series is prepared, most with respect to the input signal therein M-sequence, such as a small output of the high-frequency component and a DC component is obtained is configured to be selected. 7 2 precoder 1/1 for Pasha Le response class 4 detection type - calculation of D 2 (D is the unit delay circuit) is performed. The precoder output of this recording amplifier 1 2 A, 1 2 magnetic heads 1 3 via the B Alpha, by 1 3 beta, recording and playing, amplifying the playback output playback amplifier 2 1 Alpha, the 2 1 beta It has been made as to 0

In a seventh diagram showing the configuration of a channel decoder 2 2, 7 3 shows the processing circuits of the reproducing side of the partial response class 4, 1 + D operations of playback amplifier 2 1 Alpha, to the output of the 2 IB It is performed Te. 7 4 represents a so-called Viterbi decoding circuit, by calculation using correlation and probability of data with respect to the output of the arithmetic processing circuit 7 3, decoding of strong data noise is performed. The output of the Viterbi decoding times 7 4 is supplied to a descramble circuit 7 5, data sequence replaced secretly by scrambling at the recording side is in the raw data back to the original sequence is restored. The bi evening bi decoding circuit 7 4 used in the examples of this, than the case of performing decoding for each bit, is obtained an improvement of 3 d B in regeneration CZN terms.

d. Tape heads system

Head 1 3 A and 1 3 B to the above-described magnetism, sea urchin by that shown in FIG. 8 A, with respect to the rotating drum 7 6, are attached to take in the opposing distance of 1 8 0 °. Alternatively, as shown in FIG. 8 B, it is installed in the drum 7 6 in a form as head 1 3 A and 1 3 B gar structures to magnetic. The peripheral surface of the drum 7 6, slightly large squid than 1 8 0 °, or magnetic tape (not shown) at slightly less winding angle is wound at an angle. The head arranged to shown in FIG. 8 A, the magnetic to head 1 3 A and 1 3 B is in contact with the substantially alternately with respect to the magnetic tape, the head disposed to the shown in FIG. 8 B, the magnetic head 1 trioctahedral and 1 3 B scans the magnetic tape at the same time.

Magnetic heads 1 3 A and 1 3 extending direction of the gap of each of B

(Referred to as azimuth angle) is different. For example, as shown in FIG. 9, between the head 1 3 A to the magnetic 1 3 B, azimuth angles of ± 2 0 ° is set. The Ri by the difference of the azimuth angles, a magnetic tape, the recording pattern shown in the first 0 Figure is formed. As can be seen from the first 0 Figure, tracks TA and TB adjacent formed on the magnetic tape, the magnetic azimuth angle is a phase differences head 1 3 A and 1 3 were also formed respectively by B Noto Become. Therefore, during reproduction, the azimuth loss, it is possible to reduce the amount of crosstalk between Tonarigo cormorants tracks. The first Figure 1 A and the first 1 Figure B shows a more specific configuration of the case of the integral structure of the magnetic heads 1 3 A, 1 3 B (so-called double azimuth heads). For example, for on the drum 7 6 which is rotated at a high speed (common rotational speed in the NTSC or PAL) 1 5 0 rps, One takes the head 1 3 A and 1 3 B to a monolithic magnetic vignetting , the lower drum 7 7 there is a fixed. Thus, magnetic tape - on-flop 7 8, in the case of the NTSC system, one field of de Isseki are recorded divided into five tracks. The segmenting preparative method, it is possible to shorten the length of the track, small errors linearity of tracks Kudekiru. It is wound-out with the angle 0 of the magnetic tape 7 8 for example, 1 6 6 °, the drum type ø is the 2 5 瞧以 under example 1 6. 5 mm.

5. When 5 you realize recording of small consisting track pitch such as m, the mechanical error of the relationship Surue' de drum mechanism compatibility devices, static track linearity error one , error one dynamic tiger Kkingu a pair Ali ing the head 1 3 a and 1 3 B to a pair of magnetic.

Error one static track linearity, non-linearity of the lead on the drum, resulting in-out misalignment, inclination of the rotation axis of the drum 7 6 tape running system. Nonlinearity of the lead, adjusting bad tape running system is related to the track length, the inclination of the rotation axis is related to the diameter of the drum 7 6. In other words, Tiger Kkingu function indicating a static track linearity is proportional to track Kupitchi, inversely proportional to the product of the track length and the drum diameter. In the above example, as compared with the conventional 8 MMV TR, reduced drum diameter from 4 0 mm to 1 6. 5 mm, since the track length decreases from 7 4 negation 2 6 marrow, the track pitch 5.5 it is // rather small as m, the resulting tracking function on 8 mm VTR or more. Accordingly, not more than the conventional static track linearity error.

In addition, using a double azimuth heads, it is carried out simultaneous recording. Normally, the eccentricity of the rotating portion of the upper drum 7 6, the vibration of the magnetic tape 7 8 occurs, error dynamic tracking occurs. As shown in the first 2 Figure A, even pressing the magnetic tape 7 8 below the? Vignetting, and as shown in 1 2 Figure B, the magnetic tape 7 8 is pulled upward, thereby the magnetic tape 7 8 vibrates, the linearity of the track deteriorates. However, compared to that head to a pair of magnetic in 1 8 0 ° are opposed to each other, by performing the simultaneous recording in head to dub Ruajimasu, small errors of such Toratsuki ring Kudekiru. Further, head to the double azimuth, since the distance between the heads is small, there is an advantage that it is possible to perform the pairing more precise adjustments. Such head system to a tape, it is possible to perform recording and reproducing of the tracks of narrow width.

Thus, it is possible to reduce errors caused by tape heads mechanism 5. As 5 m, small les, be performed recorded at a track pitch can be achieved.

e. electromagnetic conversion system

Next, a description will be given electromagnetic conversion system used in the present invention. First, a magnetic tape as a recording medium is manufacturing in the following manner.

That is, the thickness of 7 zm polyethylene phthalate (PET) film Yori made based on, after coating the solution containing the Emarujo down mainly containing § click acrylic acid ester Rate' box, and drying, based the formation of the Emarujiyo down fine particles by Li Cheng fine protrusions on the one main surface. Based surface roughness subjected to such processing, the density of the center line average roughness R, in 0. 0 0 1 5 / zm, or microprojections was about 5 0 0 thousands thigh 2.

Thereafter, it has 甩 the vacuum evaporation apparatus shown in the first FIG. 3, as follows is formed by oblique deposition in the magnetic layer in an oxygen atmosphere which contains a C 0 on the base Ichisu.

In the first 3 Figure, reference numeral 8 1 a, 8 1 b is the vacuum chamber, 82 is a partition plate, 8 3 is a vacuum exhaust valve. 8 4 supply roll base beta, 8 5 the take-up roll, 8 6 Guy Dror, 8 7 a, 8 7 b is a coulis Nguki Ya down Guy sul cylindrical base B. Also, 8 8 a, 8 8 b is an evaporation source of C o, .8 9 a, 8 9 b is an electron beam heating evaporation source 8 8 a, 8 8 b, respectively. 9 0 a, 9 0 b Habe shield for regulating the incident angle of the evaporation beams 对 to Ichisu B, 9 1 a, 9 1 b is the introduction pipe of the oxygen gas.

In such a vacuum vapor deposition apparatus thus configured, the base B is transported from the supply roll 8 4 coulis Ngukyan 8 7 a, Guy Dror 8 6, coulis Ngukyan 8 7 b, in the order of the take-up roll 8 5. At this time, Oite the coulis Ngukyan 8 7 a, 8 7, a magnetic layer composed of two layers C 0 layer in an oxygen atmosphere is formed by oblique vapor deposition.

The vacuum deposition, while maintaining the vacuum chamber 8 1 a, 8 1 b to a vacuum degree of 1 x 1 0- 'Torr, introduced into these vacuum chamber 8 1 a, 8 in 1 b Bruno. Conducted while introducing oxygen gas at a proportion of 2 5 0 cc / min by Eve 9 1 a, 9 1 b. In this case, the incident angle of evaporation bi chromatography beam relative to the base B is in the range of 4 5 to 9 0 °. Also, C o layer is deposited to a thickness of each 1 0 0 0 A in coulis Ngukyan 8 7 a, 8 7 b, Ru total thickness of the magnetic layer is a 2 0 0 0 A ο

In this way, the base B of the magnetic layer is formed consisting of C 0. layer of two layers, the bets Ppuko preparative carbon and Epokishi system consisting of binder Bas Kkuko preparative and consisting par full O b polyether lubricant after applying, to produce a magnetic tape and cut it into 8 thigh width.

Characteristics of the finally obtained magnetic tape, a residual magnetic flux density B r

= 4 1 5 0 G, coercivity He = 1 6 9 00e, R s = 7 9 der ivy. The surface roughness of the magnetic tape, reflecting the surface roughness of the base B, the center line average roughness R, in was very small and 0.1.

The measurement of the surface roughness is usually performed by JISB 0 6 0 1, the measurement of this time was performed under the following conditions.

Measuring instrument: Other Li step (made by Rank Taylor Co., Ltd.)

Needle diameter: 0. 2 X 0. 2 m, the squareness needle

Stylus force: 2 mg

Nono I-pass filter: 0. 3 3 Hz

The first 4 figures show head to the recording magnetic for use in the present invention. As shown in the first 4 figures, head to this magnetism, monocrystalline Mn- Zn ferrite core 1 0 1 A, 1 0 1 B on the formed Ri by the sputter evening method the F e- G a - S i - and a gap 1 0 4 between R u soft magnetic layer 1 0 2, 1 0 3. This is on both sides of the gears-up 1 0 4 in the track width direction is glass 1 0 5, 1 0 6 Takashi塡, this Yotsute track width is regulated to about 4 / zm wide. 1 0 7 a winding hole, recording coil in this 卷線 hole 1 0 7 (not shown) is wound. The effective gear-up length of the head to the magnetic is 0.5.

Head is to the magnetic saturation flux density B in the vicinity of the gap 1 0 4, but 1 4. 5 k G of F e - a R u soft magnetic layer 1 0 2. 1 0 3 - G a- S i due to the use, it is possible to perform the recording without the even against a high coercive force of the magnetic tape results in magnetic saturation of the head.

Te cowpea to the use of head to ΜΕ tape and the magnetic as described above, 1. 2 5 m 2 Zb it less recording density can be realized. That is, as described above, 1. 2 5 ^ m 2 Zb it is achieved by recording the signal of the shortest wavelength 0. 5〃M the track width of 5〃M. However, CZN reproduction output are known to degrade as the recording wavelength and track width are reduced, in order to suppress this deterioration, head configuration tape and into the aforementioned are used.

The applicant, was a prototype di digital VT R of the shortest wavelength 0. 5〃M using the 8 wicked person ME tape in 1 9 8 8 years in truck pitch 1 5〃M. At this time rotates the drum 6 0 r pm using a rotary drum 4 0 mm diameter, was recorded reproduction. The recording wavelength 1 m in this system, the C / N of 5 1 d B was obtained. Bit 'Erare bets of the system was 4 X 1 0 one 5.

As in the embodiment of the invention, 5 the m that use track width, so that the C / N not only obtained image quality of about 4 4 d B of the same specification is deteriorated. To compensate for this 7 d BC / N degradation, so that is used configuration of the invention described above.

That is, generally recorded and scan Beshingu between head to the tape during playback it is known that the signal output level is reduced if the size Kunare, the amount of spacing Yi flatness of the tape it is also known to reside. In the case of the coating type tapes, but the flatness of the tape one-flop dependent on the coating material, in the case of evaporated tape, it is known to depend on the flatness of the base itself. In the embodiment above mentioned, the experimental result that C ZN increases 1 d B by selecting the surface roughness of the base film as much as possible into small is obtained. Further, the vapor deposition material of the embodiment described above, by using a vapor deposition method, CZN improvement in 1 9 8 1996 3 d B in pairs to 甩 need tape prototype when the is obtained as a result of the experiment. From the above, by using the heads and tape of the present invention, so that the increase of C / N of 4 d B were obtained for the previous prototype.

Further, in this invention, since the Biyubi decoding is used for channel decoding, it was confirmed that the increase of 3 d B the decoded for each bit that was used in previous prototype is obtained .

Thus, it is possible to compensate for the CZN deterioration amount as a whole 7 d B, it becomes one. 2 5 at a recording density of 〃M 2 bit, the 1 9 8 8 years equivalent error one rate and prototype is obtained . And about the reproduction output, when the error rate of the previous stage of the correction process of the error correction code is needed to be at 1 0 _ 4 below, using the error correction code redundancy of about 2 0% correction the amount of the extent possible in order to reduce the E error.

This invention, therefore can record di digital image signal in a small becomes a track pitch, the recording density. Can be increased, it is possible for a long time recording and reproducing using a small cassette. Since the diameter of the rotary drum is small, in reducing the size of the mechanism portion 93

02

2 I

0 t

9

SSZ.00 / l6df / JOd ε 厶 060 / Z6 OAV

Claims

The scope of the claims
1. a proc means for converting the input di digital image signal comprising a plurality of pixel data pro Tsu data of click units Isseki, encoding means for compression encoding to the proc unit output data of the plot click means When, and a channel coding means for tea down channel encoding the output encoded data of the encoding means, the head of the output data of the Chillan panel Goka means to the magnetic mounted on the rotary drum, the magnetic in the magnetic recording apparatus of di digital Menzo signal it is recorded on the tape,
5 the pitch of the tracks formed on the magnetic tape by the head to the magnetic. 5 m or less and no, select the diameter of the rotary drum below 2 5 mm, 1 the rotation speed of the rotary drum 5 0 by forming a rps or higher, the magnetic recording apparatus of the di digital image signal to Toku徵 in that the track length per unit time as the predetermined.
2. The compression encoding means, DCT (Di screte Cos i ne Transf orm) magnetic recording apparatus di digital image signal of Claims claim 1 wherein the Toku徵 that it is.
3. The above channel encoding means, a magnetic recording apparatus of di digital image picture signal of Claims claim 1 wherein the Toku徵 that the adaptive scrambling circuit.
4. the channel encoding means further magnetic recording apparatus of di digital image signal of the third term recited claims having a precoder for partial Response 'class 4 detection type.
5. the adaptive scrambling circuit comprises a plurality of M sequence, the claims highest frequency component and Μ series low not output can be obtained in the DC component is made to be selected for the input signal in which the the magnetic recording apparatus of the di digital image signals of the three terms described.
PCT/JP1991/000755 1990-11-14 1991-06-05 Device for recording digital picture signal WO1992009073A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP2307508A JPH04179380A (en) 1990-11-14 1990-11-14 Magnetic recorder for digital picture signal
JP2/307508 1990-11-14

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US08/768,871 US5384666A (en) 1990-11-14 1991-06-05 Digital picture signal recording apparatus in which a field interval is recorded in a plurality of tracks exhibiting a track pitch no greater than 5.5 μm by a rotary drum having a diameter no greater than 25 mm and a rotary speed no less than 150 rps
CA 2073194 CA2073194C (en) 1990-11-14 1991-06-05 Magnetic recording apparatus of digital picture signal
US08/219,957 US5512349A (en) 1990-10-31 1994-03-30 Method and apparatus for magnetic recording digital video signals and magnetic recording medium therefor

Publications (1)

Publication Number Publication Date
WO1992009073A1 true WO1992009073A1 (en) 1992-05-29

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Application Number Title Priority Date Filing Date
PCT/JP1991/000755 WO1992009073A1 (en) 1990-11-14 1991-06-05 Device for recording digital picture signal

Country Status (3)

Country Link
JP (1) JPH04179380A (en)
CA (1) CA2073194C (en)
WO (1) WO1992009073A1 (en)

Cited By (3)

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Publication number Priority date Publication date Assignee Title
US5702754A (en) * 1995-02-22 1997-12-30 Meadox Medicals, Inc. Method of providing a substrate with a hydrophilic coating and substrates, particularly medical devices, provided with such coatings
US6468649B1 (en) 1995-02-22 2002-10-22 Scimed Life Systems, Inc. Antimicrobial adhesion surface
US6558798B2 (en) 1995-02-22 2003-05-06 Scimed Life Systems, Inc. Hydrophilic coating and substrates coated therewith having enhanced durability and lubricity

Citations (4)

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Publication number Priority date Publication date Assignee Title
JPS59119519A (en) * 1982-12-27 1984-07-10 Sony Corp Recorder of pcm signal
JPS62262208A (en) * 1986-05-07 1987-11-14 Mitsubishi Electric Corp Rotary head type magnetic recording and reproducing device
JPS63306504A (en) * 1987-06-08 1988-12-14 Canon Inc Digital signal recorder
JPH01307003A (en) * 1988-06-03 1989-12-12 Hitachi Ltd Rotary head type pcm recording and reproducing device

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Publication number Priority date Publication date Assignee Title
JPS59119519A (en) * 1982-12-27 1984-07-10 Sony Corp Recorder of pcm signal
JPS62262208A (en) * 1986-05-07 1987-11-14 Mitsubishi Electric Corp Rotary head type magnetic recording and reproducing device
JPS63306504A (en) * 1987-06-08 1988-12-14 Canon Inc Digital signal recorder
JPH01307003A (en) * 1988-06-03 1989-12-12 Hitachi Ltd Rotary head type pcm recording and reproducing device

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5702754A (en) * 1995-02-22 1997-12-30 Meadox Medicals, Inc. Method of providing a substrate with a hydrophilic coating and substrates, particularly medical devices, provided with such coatings
US6048620A (en) * 1995-02-22 2000-04-11 Meadox Medicals, Inc. Hydrophilic coating and substrates, particularly medical devices, provided with such a coating
US6468649B1 (en) 1995-02-22 2002-10-22 Scimed Life Systems, Inc. Antimicrobial adhesion surface
US6558798B2 (en) 1995-02-22 2003-05-06 Scimed Life Systems, Inc. Hydrophilic coating and substrates coated therewith having enhanced durability and lubricity

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JPH04179380A (en) 1992-06-26
CA2073194C (en) 2000-08-01

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