JPS59202783A - System and apparatus of vtr recording and reproducing - Google Patents

Abstract

PURPOSE:To attain substantially recording/reproducing with high picture quality and high sound quality by arranging the recording track of picture information and sound information in parallel and alternately in a prescribed direction where the track crosses in the tape lengthwise direction and attaining azimuth recording where the azimuth angle of adjacent recording track is different from each other. CONSTITUTION:The recording tracks are arranged in the tape lengthwise direction, i.e., in parallel with the direction where the tracks cross in the tape running direction D at a prescribed angle S, and picture tracks VD1, VD2 and sound tracks PCM1, PCM2 are arranged alternately. Further, the so-called azimuth recording is conducted, where adjacent tracks are provided with a different azimuth angle in order to reduce the mutual interference between the video tracks VD1, VD2 and the sound tracks PCM1, PCM2. In taking the azimuth angle of sound exclusive use heads AH1, AH2 as 0 deg., the reproduced waveform with a good S/N is obtained.

Description

[Detailed Description of the Invention] The present invention provides lead recording//
This article relates to playback technology, and in particular to VTR recording and playback systems and devices that are optimal for recording/playback audio information in the form of PCM (pulse code modulation) encoded information along with image information in rotary/radial helical scan systems. .

[Background of the invention]

Conventional one-turn delivery ＼ Helical scan method V T
R Lj In general, it is difficult to obtain sufficient sound quality compared to the image quality. Examples of reasons for not having enough Y and green onions include the following. Conventionally, in this type of VTR, image information is recorded/played by helical scanning using a rotating head, but audio information is recorded/played using a fixed head. The relative speed between the magnetic tape and the head is slow, and the frequency band that can be recorded becomes narrow.
Since the image information, that is, the video signal, is recorded on the magnetic tape in the first place by helical scanning, the recording trunk for the audio information, that is, the audio number, that is, the audio track is formed with a narrow track width □ at the edge of the tape. In addition to the slow relative speed mentioned above, the signal-to-noise ratio (S) deteriorates.

Therefore, various methods have been considered to improve the sound quality in VTRs as described above.

For example, if the audio signal is Full. (Frequency modulation) A method of modulating and multiplexing it into a video signal has been considered, but this method has the problem of having a negative effect on image quality when trying to widen the audio band.

Also, a method of compressing and recording PCM information during the blanking period of the video signal is also being considered. However, in this case, there is a problem that the planking period [j41 is insufficient time and is sufficient to obtain grandson quality speech: it is not possible to record a PCM code with a number of bits.[Objective of the Invention] The present invention The purpose of this is to improve the recording conditions of audio 1^ information and to develop a VT that can realize high image quality and straight-haired recording and playback.
The object of the present invention is to provide an R-recording relearning formula and a device directly used for its implementation.

[Summary of the invention]

The present invention has a recording format for image and audio information of a VTR, in which recording tracks of image information and audio information are alternately arranged parallel to a predetermined direction intersecting the longitudinal direction of the tape.
The azimuth recording is characterized in that the azimuth angles of adjacent recording tracks are [4].

[A surefire example of invention. , I An example of the present invention will be described with reference to FIGS. 1 to 3.

FIG. 1 schematically shows the structure of the one-transfer head in this embodiment fQ.

As shown in the figure, the two heads VHJ and vj2, which form a pair on the rotating tram RD, are placed at a position of approximately 18 oO.
Iseisengetsu/Head VH 7.

If the attachment position D5 of one head VHz of VH2 is the reference position of the rotating drum RD, that is, the ψ position, then the other head V
H2 is mounted at approximately 180°. The configuration up to this point is similar to that of a rotary head in a conventional VTR. Further, in this embodiment, two audio dedicated heads AHJ and AH2 are provided on the rotary drum RD, for example, exclusively for audio information input from PCM code information. These two audio-only heads AH1, A)f2 forming a pair are at approximately is oO different U on the oral tram RD, and at such a position that they form a relative angle θ with the image-only heads vH1, VB2. Attach. The angle θ is set in accordance with the required image track and sound (PCM) track width ratio. FIG. 1 shows the case where the angle θ is approximately 120°, and the head AH7 is
/ About 120 degrees to this position ii', head A H2 cuff n: 30 CP (position D).

Section 2 (I) is the first section to explain the operation of the rotary head constructed as described above.

That is, in the conventional NrTR, the head, Dowa, and tape T can be rotated approximately 1800 times (fast rotation) on the rotating drum RD. T.G.J. 1゛G2 is a tape guide.

In this state, the rotary drum RD is rotated in the direction of the arrow R, and at the same time the tape T is run in the direction of the arrow in the figure. This operation causes each head on the rotating drum RD to move from VH2 to A.
Tape in the order of HI → VH2 → AH2.

In this case, the tape T contacts the tape T and scans the recording surface to alternately record image information and audio information one track at a time.
The recording format on the recording surface is shown in FIG.

In FIG. 3, VD and VD2 are respectively two image dedicated heads VI (L and VH2 recorded by J and VH2).
ii image track, and PCM1 and PCM2 indicate audio tracks recorded by audio-only heads AHJ and AH2, respectively. As shown in the figure, the recording tracks are arranged parallel to each other at a predetermined angle S with respect to the tape longitudinal direction, that is, the tape running direction, and the image tracks VD1. VDz and audio track PC
M1. PCMz alternates ((pain distribution.

has been done. And these image tracks VD], VD
2 and audio track PCM1. The ratio of the track width to the PCM2 may be appropriately set as necessary. In other words, in this case, the audio information is PCM encoded digital information, so the S/N is lower than that of image information consisting of analog information.
There's a lot of leeway. Therefore, as shown in the figure, the image track VD1. Audio track PCIVIJ compared to VDz,
PCM2 can be narrowed. The width of the recording track is determined by the width of the head and the relative angle at which the head is attached to the rotating drum RD. In this case, since azimuth recording is performed as described later, there is very little mutual interference between adjacent recording tracks, and not only is a guard band unnecessary, but even if the recording tracks overlap somewhat, there are many conjugations that are problematic. . 17 Therefore, in such case 1, the width of the recording head is not i8, but
The above-mentioned image dedicated heads VH1, VH/' and audio 7. To Toyokawa"71'A HJ, it is a good idea to set the relative defeat angle of 1 degree θ with AH2 correctly to the required trunk width ratio.In addition, in the case of Figure 3, the track width ratio of image and audio is approximately 2:1 (corresponding to θ; 120°).

Furthermore, in this case, adjacent recording tracks, namely image tracks VDJ, VD2 and audio tracks PCMJ, PC
In order to reduce mutual interference with M and 2, so-called azimuth recording is performed in which the instantaneous contact tracks have different azimuth angles.

Specifically, for example, many VTRs currently perform azimuth recording by setting different azimuth angles between adjacent image tracks, and record audio at an azimuth angle between the two on an audio track inserted between them. Tracks may be set uniformly.

More specifically, many of the current VTRs have an angle of approximately 180 degrees.
For example, image tracks are recorded by setting azimuth angles that are symmetrical about +( and -chi) for each of a pair of image-dedicated heads set at different rotational positions. Since the image-only heads VHJ and VH2 intersect with these heads, if the azimuth angles of the audio-only heads AH2 and IAH2, which are in charge of the audio tracks inserted between them, are both set to φ, the following advantages will occur.

P) Set the azimuth angle of the audio dedicated heads AH1 and AH2 to 0.
By setting it to 0, the relative speed and recording signal reproduction efficiency are theoretically maximized. Therefore, set it to another azimuth angle 'f? : In this case, the recording frequency band of the audio information signal can be widened, and the reproduced waveform with good S/N ratio8
It is possible to pray.

(0) Image dedicated head VH1, V, H2 horse mackerel 77
Since the angles are set to +α and -α, it is possible to match the azimuth angle of the image head of current VTRs, such as α that way and 7 degrees. ).

Please note that this gift image information is mutual &! VTRI' trying to have sex! l: Records in a predetermined video signal format (intensity, modulation, and recording method) that corresponds to the video signal format. In addition, PCM audio information is processed using the consumer PCJVJ encoder/decoder (EIAJ standard STC-007,) specified by the Electronic Machinery Industries Association of Japan.
Use hiteo format. ), or in a separately determined format (correction codes, etc. may be added as necessary). It goes without saying that in recording this PCM sound P information, a modulation method and recording method different from the modulation method and recording method used in the 5-pin recording of the information outside the image, such as a saturation recording method, etc., may be used. .

In this way, by alternately recording image information and audio information one track at a time, audio information can be converted into digital values (P
CM code). therefore,
Since the audio information is converted into PCM, there is no deterioration in sound quality due to dubbing (this is a major feature of PCM). Similarly, since the same track length as the image track is obtained for audio information, it is possible to secure a quantization bit number of 14 bits or more in the audio frequency band of 20 to 20 KHz, resulting in a good S/N.

High-fidelity recording and playback can be achieved by obtaining distortion characteristics and sufficient dynamic range.

1. One advantage of recording image information and audio information alternately on one track at a time is that
One example of this is that it can reduce crosstalk of color signals (chroma). In other words, since the color signal is converted to a low frequency band, the recording frequency is low (approximately 629 IIG(z)), and the crosstalk reduction effect of azimuth recording becomes weak.
In azimuth recording, the lower the frequency, the more severe the crosstalk becomes. ) However, in this embodiment, since a large amount of audio information including color information is distributed between old tracks, the color reputation crosstalk between image tracks becomes extremely small.

Of course, the VTR of this embodiment can also be used as a CM recording/playback machine, which has high-quality interlocking recording/playback functions, by using only the audio head (audio track).

Note that the present invention is not limited to the embodiments described above and shown in the drawings, but may be modified in any way. Various modifications can be made within the scope.

For example, if compatibility with the conventional system (current system) is not considered, it is only necessary to make sure that the angles do not match between adjacent tracks. , VH2 may be exchanged, or the azimuth angles may be made different between the image-only head and the audio-only head, as shown in the striped diagram 4.

That is, FIG. 4 schematically shows the recording format, and for image quality 4 h' V H,1', VH2
' is set to a common first azimuth angle, image tracks VD1' and VD2' are recorded/saved, and both audio heads AHJ' and AHz' are set to a common first azimuth angle. The audio tracks P CM 2' and P CM z' are recorded/played at an azimuth angle of 2.

In addition, in the above description, it was not specified whether the image-only head or the audio-only head is a recording/playback head, a recording-only head, or a playback-only head, but if it is a normal VTR, any of them can be used for both recording and playback. Generally, a head is used, and if a recording-only head and a playback-only head are used, each can be configured as described above.
A combination of a recording/reproducing head, a recording-only head, and a reproduction viewing angle head may be used.

Of course, when configuring it as a VTR exclusively for MJ recordings or a VTR exclusively for regeneration, it is necessary to use
Alternatively, it is necessary to use a playback-only head, but it is also possible to use separate rotating drums for recording and playback, or separate rotating drums for audio and images.

[Efficacy of “From:”]

According to the present invention, it is an object of the present invention to provide a raw VTR recording method and its equipment that can improve the recording process of audio information and realize recording and reproduction with high picture quality and high sound quality.

[Brief explanation of drawings]

FIG.
FIG. 2 is a schematic diagram for explaining the operation of the embodiment, FIG. 3 is a schematic diagram for explaining the recording format of the embodiment, and FIG. 4 is a schematic diagram for explaining the recording format of the embodiment. FIG. 7 is a schematic diagram for explaining a recording format in another embodiment. VH7, VH2, VH1', VH2' - Image-only head, Al7. Al1. AMP', AH2'...Audio/dedicated head, RD...rotating drum, T...magnetic tape.

Claims (1)

[Scope of Claims] (1) Recording of image information and audio information on the same magnetic tape at the same time. (4) On the recording surface (at C), the recording tracks arranged parallel to a predetermined direction intersecting the longitudinal direction of the tape are arranged alternately one track at a time, and have an azimuth angle that corresponds to that of the adjacent recording tracks. (5) A VTR recording and reproducing method characterized in that the image information is recorded using an azimuth pointer, and the image information is simultaneously and separately reproduced using the azimuth angle. (2) Claims M! In the VTR recording and reproducing method described in item (1), the azimuth angle is alternately set to +α and -α (α<900) for the image information track, and uniformly set to ψ for the audio information track.
TR recording and playback method. In the VTR recording and reproducing method described in claim (1), the azimuth angle is set to −f41 for each of the image information track and the audio information track, and the azimuth angle is made different between the image information track and the audio information track. A VTR recording and playback system characterized by: In the VTR recording and reproducing method according to claim 1 of claims (1) to (3), the audio information is I)
A VTR characterized by recording in the form of CM code information
Recording and playback method. In a VTR that records/reproduces image information using a rotating head helical scan method, two dedicated rotating heads are used for image information and audio information, and two rotating heads are used for each of the above. 18oO heads
The two sets are arranged at different rotational angle positions and at a relative angle corresponding to a predetermined track width ratio between the WJ image information and the audio information, and are arranged on approximately the same circumference, and in the head rotation direction. vTRo ( 6) In the VTR described in claim (5), the two single-plane image information heads are set at different azimuth angles other than ψ, and the two audio production and information heads are both set at 00. Set the azimuth angle of I~t\! f
VTR 8 (7) In the VTR described in claim (5), the head for picture information and the head for sound piece information JY are uniformly used among heads of the same type, and monthly between heads of different types. VTR8 characterized by being set at different azimuth angles