JP3232669B2 - Magnetic recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus for recording / reproducing a plurality of types of information signals having different data rates.

[0002]

2. Description of the Related Art A magnetic recording / reproducing apparatus (VTR) for recording and reproducing, for example, a video signal as an information signal on a magnetic tape includes a digital VTR for recording and reproducing data obtained by digitizing the video signal. FIG. 8 shows a conventional block configuration of this digital VTR. Reference numeral 50 denotes a digital data input terminal relating to, for example, a video signal, 31 denotes a recording processor, 32 denotes a digital modulator, and 53 and 54 Heads having different azimuths disposed opposite each other, 58 is a magnetic tape, 60 is a digital data output terminal, 41 is a reproduction processing unit, and 42 is a digital demodulator.

[0003] Digital data such as a video signal input to a digital data input terminal 50 at the time of recording is recorded by a recording processing unit.
At 31, the digital code is output to a modulator 32 as an error correction coded digital code for detecting and correcting an error.
The modulator 32 converts the input digital code into a signal in a form suitable for recording, and the magnetic head 53 on the rotating drum 57
At 54, the data is recorded on the magnetic tape 58.

The signals reproduced by the magnetic heads 53 and 54 at the time of reproduction are converted into the original digital codes by the demodulator 42, and the reproduction processing unit 41 performs error correction decoding for detecting and correcting a code error caused by the recording / reproduction process. By doing so, digital data in the same signal form as during recording is output to the digital data output terminal 60.

When recording a video signal,
HDTV is being put into practical use and N is the current TV signal
It is desired that different signal forms called TSC, that is, video signals having different information amounts can be recorded by the same digital VTR. It is also desired that even if the video signals have the same signal form, digital codes having different information amounts can be recorded by the same VTR according to the length of the recording time. In other words, the same VTR must be able to perform recording and reproduction corresponding to different data rates.

[0006]

However, the configuration of the conventional digital VTR shown in FIG. 8 can only cope with recording and reproduction at a single data rate.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and a VTR capable of recording and reproducing information of a plurality of different data rates with the same digital VTR.
It is an object of the present invention to realize a predetermined speed reproduction without any noise at least with respect to information of a high data rate.

[0008]

According to the present invention, there is provided a magnetic recording reproducing apparatus comprising:
The raw device is placed on a rotating drum that rotates at a predetermined drum speed.
At a predetermined traveling speed by scanning a predetermined number of heads provided
The first information is recorded on the running recording medium or at the normal speed.
At the predetermined drum rotation speed (r: from 1: 1)
A large positive number) provided on the rotating drum that rotates
By scanning a predetermined number of heads, the predetermined traveling speed
On the recording medium running at 1 / r, the first information
The second information consisting of the information amount of about 1 / r is recorded or
Speed reproduction is performed, and 1 / r (r: 1
Before being provided on the rotating drum that rotates at a larger positive number)
The predetermined traveling speed is obtained by scanning the predetermined number of heads.
Before being recorded on the recording medium traveling at 1 / r of
A magnetic recording / reproducing apparatus that reproduces the first information at 1 / r speed is provided.
When the first information is reproduced at 1 / r double speed, the r
The information of one field that is sequentially reproduced every field period
Reproduction for each field obtained by compressing the time axis to 1 / r
The information is used continuously for r field periods. Ma
Further, the magnetic recording / reproducing apparatus according to the present invention can
Of a predetermined number of heads provided on a rotating drum
Inspection on a recording medium running at a predetermined running speed.
1 Record information or reproduce at normal speed, and
Before rotating at 1 / r of rotation speed (r: a positive number greater than 1)
The scanning of the predetermined number of heads provided on the rotating drum
Thus, the recording that travels at 1 / r of the predetermined traveling speed
On the medium, the information amount is approximately 1 / r of the first information.
The second information is recorded or reproduced at normal speed, and the predetermined
Rotate at 1 / r (r: a positive number greater than 1)
For scanning of the predetermined number of heads provided on the rotating drum
Therefore, the above-mentioned travel at 1 / r of the predetermined travel speed is performed.
The first information recorded on the recording medium is 1 / (2 ·
r) In the magnetic recording / reproducing apparatus for performing double-speed reproduction, the first
During 1 / (2 · r) double speed playback of information, the r field period
In one field that is sequentially reproduced every interval, one field
Select one of the fields that make up the frame
Then, for each field obtained by compressing the time axis to 1 / r
The playback information is used continuously for 2r fields.
is there.

[0009]

In the 1 / r speed reproduction of the first information, r
One field of reproduction information obtained by compressing the time axis of the information of one field sequentially reproduced in each field period to 1 / r times is used for the r field period.

In the 1 / (2 · r) double speed reproduction of the first information, one of the fields constituting one frame is selected from one field sequentially reproduced every r field periods. Then, the reproduction information for each field obtained by time compression to 1 / r is used continuously for a period of (2 · r) fields.

[0011]

【Example】

Embodiment 1 FIG. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows recording / reproducing system blocks when performing recording / reproducing corresponding to high data rate information (first information) and low data rate information (second information). In the figure, reference numeral 50 denotes, for example, a digital data input terminal relating to a video signal; 51, an encoder; 52, a digital modulator comprising, for example, two channels; one set of 71A and 71B;
The other set of A and 72B is approximately 18
2 different azimuths that are arranged at 0 degree
A pair of heads, 58 is a magnetic tape, 60 is a digital data output terminal, 61 is a decoder, 62 is a digital demodulator consisting of, for example, two channels, 65 is a selector, and 66 is a compressor.

First, the case of recording the first information will be described. Digital data relating to first information such as a video signal input to the digital input terminal 50 at the time of recording is subjected to error correction coding for detecting and correcting errors and channel division corresponding to the number of recording channels in the encoder 51. Then, for example, two-channel digital codes are output to the digital modulator 52, respectively. The modulator 52 converts the input two-channel digital codes into signals in a form suitable for recording.
Recording is performed on the magnetic tape 58 by a set of magnetic heads 71A to 72B.
In this case, different azimuths θ arranged at almost the same position
One set of magnetic heads 71A, 71B and 72A, 72B of 1, θ2
A pair (two) of tracks having different azimuths are alternately recorded and reproduced almost simultaneously by another set, and four tracks are scanned per rotation of the rotating drum. Here, the number of rotations of the head when recording the first information is R, and the tape speed is V.

FIG. 2 shows a track trace state in the case where the recording corresponding to the first information described above is performed. In the figure, 1
Is a head scanning direction, 2 is a tape running direction, and a pair (two) of the tracks 81A and 81B of the tracks 81A to 82B on the magnetic tape 58 are, for example, magnetic fields of different azimuths θ1 and θ2 arranged at substantially the same position. The tracks 82A and 82B are recorded almost simultaneously by another set of magnetic heads 72A and 72B having different azimuths θ1 and θ2. Here, for example, the information of one field period T in the first information input to the input terminal 50 is:
It is assumed that it is composed of four tracks 81A to 82B during the time T required for one rotation of the drum.

FIGS. 3A and 3B are timing charts at the time of recording the first information described above. FIG. 3A shows time, and FIG. 3B shows two channels related to the first information output from the encoder 51 or the modulator 52. , For example, D1A, D1
The four signals B, D2A, and D2B form a recording signal of the first information corresponding to one field. Then, during the T / 2 period in which the drum makes a half rotation, the recording signals D1A and D1B of two channels are applied to the heads 71A and 71B, respectively.
The recording tracks 81A and 81A of FIG.
B is formed. The time T / when the drum next makes a half turn
During the T / 2 period from 2 to time T, the recording signals D2A and D2B of two channels are simultaneously recorded by the heads 72A and 72B, respectively, and the recording track 82 of FIG.
A and 82B, one rotation of the drum,
At time T corresponding to the field period, 81A to 82B
Are formed.

Next, in normal speed reproduction, as in the first information recording, the head rotation speed is R and the tape speed is V, and reproduction is performed in exactly the same track trace state as in the recording. 3B reproduced from the recording track of FIG. 2 by the magnetic heads 71A to 72B together with the time of FIG.
Are reproduced by the demodulator 62 composed of at least two channels into the original two-channel digital codes, and the decoder 61 performs error correction decoding for detecting and correcting a code error caused by the recording / reproducing process. ,
The digital data output terminal 60 outputs digital data relating to the first information in the same signal form as that at the time of recording by performing one-channel conversion by channel synthesis.

Next, a case where a low data rate, that is, the second information is recorded will be described. Here, in order to make the description easy to understand, the information amount of the second information is set to 1/2 (1 / r) of the first information. Accordingly, the head rotation speed is set to R / 2 and the tape speed is set to V / 2. Digital data relating to second information such as a video signal input to the digital input terminal 50 at the time of recording is subjected to error correction encoding for detecting and correcting errors in the encoder 51,
Channel division corresponding to the number of recording channels is performed, and, for example, two-channel digital codes are output to the modulator 52, respectively. The modulator 52 converts the input two-channel digital codes into signals each having a form suitable for recording, and sets two sets of magnetic heads 71 on the rotating drum 57.
A to 72B record on the magnetic tape 58. In this case, a pair of (two) tracks having different azimuths are alternately recorded almost simultaneously by one set of different azimuth θ1, θ2 magnetic heads 71A, 71B and another set of 72A, 72B arranged at substantially the same position. It is reproduced and four tracks are scanned per rotation of the rotating drum.

FIG. 4 shows a track trace state when the recording corresponding to the second information described above is performed. In the figure, 1 is a head scanning direction, 2 is a tape running direction, and a pair (two) of tracks 91A and 91B of the tracks 91A to 92B on the magnetic tape 58 are different, for example, arranged at substantially the same position. Tracks 92A and 92B are recorded almost simultaneously by one set of magnetic heads 71A and 71B of azimuths θ1 and θ2 and tracks 92A and 92B by another set of magnetic heads 72A and 72B of different azimuths θ1 and θ2. Since the head rotation speed is R / 2 and the tape speed is V / 2, the information of one field period T in the second information input to the input terminal 50 is １ ／ of the drum.
It is composed of two tracks 91A and 91B at the time T required for rotation.

FIG. 3C is a timing chart of a two-channel recording signal relating to the second information output from the encoder 51 or the modulator 52 at the time of recording the second information described above. For example, two signals E1A and E1B are used. It forms a recording signal of the second information corresponding to one field. In the period T during which the drum makes a half rotation, the recording signal E of two channels
1A and E1B are simultaneously recorded by the heads 71A and 71B, respectively, and are formed as recording tracks 91A and 91B in FIG. Between time T and time 2T when the drum makes a next half rotation, the recording signal E of two channels
2A and E2B are simultaneously recorded by the heads 72A and 72B, respectively, to form the recording tracks 92A and 92B of FIG.

That is, at the time of recording the second information, both the head rotation speed and the tape speed are １ ／ of those at the time of recording the first information. The track patterns are exactly the same.

Next, in the normal speed reproduction of the second information, the head rotation speed is set to R / R as in the second information recording.
2. The tape speed is set to V / 2, and reproduction can be performed in exactly the same track trace state as during recording. The reproduced signals of two channels shown in FIGS. 3 (a) and 3 (c) reproduced from the recording tracks of FIG. 4 by the magnetic heads 71A to 72B are converted into digital codes of the original two channels by a demodulator 62 comprising at least two channels. The digital data output terminal 60 converts the signal into a one-channel signal having the same signal form as that at the time of recording by performing error correction decoding for detecting and correcting a code error caused by a recording / reproducing process in the decoder 61, or performing one-channel conversion by channel synthesis. Digital data relating to the two information is output.

Further, a case where the above first information is reproduced at 1/2 speed (1 / r speed reproduction) will be described.
The values of the number of rotations of the head and the tape speed in 1/2 speed reproduction are the same as those in the case of the recording or the normal speed reproduction relating to the second information, in other words, the values of 1/2 times the recording of the first information. 1 / 2R and 1 / 2V where
And Therefore, as described above, the track relating to the first information shown in FIG. 2 is recorded by the one set of heads 71A and 71B and the other set of heads 72A and 72B every 1/2 rotation of the drum. And head tracing can be performed in exactly the same manner. FIG. 5 (a) shows the time expressed on the same time axis as FIG. 3 (a), and FIG. 5 (b) shows a two-channel reproduced signal output from the demodulator 62 during 1/2 speed reproduction.

As is clear from the comparison with the timing chart at the time of recording the first information shown in FIG. 3B, the information is reproduced by, for example, two-channel heads 71A and 71B. The two-channel digital codes D1A and D1 constituting the first information in the half field period T / 2 during recording.
B is reproduced at a time T twice as long as the recording time. Similarly,
2 reproduced by two-channel heads 72A and 72B
The digital codes D2A and D2B of the channels are also reproduced at twice the time T during recording. That is, the recording signal of the first information in the predetermined period is reproduced in the half-speed reproduction in a period twice as long as the predetermined period, and is reproduced in a state where the recording signal is extended twice as long as the recording time. Will be.

The reproduced signal of two channels output from the demodulator 62 at the half speed reproduction shown in FIG.
The decoder output shown in FIG. 6 (b) is obtained by performing error correction decoding for detecting and correcting a code error caused by the recording / reproducing process and one-channel conversion by channel synthesis. Note that the decoder output in FIG. 6B is expressed in FIG. 6A on the same time axis as in FIG. 3A.
In FIG. 6B, F1, F2, F3, F4, F5, F6,
... Are information in units of one field for each two-field period 2.T, which is time-expanded twice as long as the recording time.
F1 is a reproduced signal D1 of two channels in FIG.
A, D1B, D2A, and D2B, and F2 is D
From 3A, D3B, D4A and D4B, F3 is D5
From A, D5B, D6A, and D6B, F4 is D7, D
This is a field obtained by channel combining from 7B, D8A, and D8B. Here, F1, F3, F5, etc. belong to the odd field, and F2, F4, F6
Etc. belong to the even field. Then, the frame FR1 is divided into the adjacent odd-numbered field F1 and the even-numbered field F3 by the adjacent odd-numbered field F3.
And an even field F4, a frame FR2, and an adjacent odd field F5 and an even field F6, a frame FR3.

The decoder output of FIG. 6 (b) is input to the selector 65, and as shown in FIG. 6 (c), for example, F1, F2, F
3, F4, F5, etc., are selected in the order of fields, and then a compressor 66 composed of a field memory or the like is used.
Is time compressed to 1/2. Time compression of 1/2 can be easily realized, for example, by reading the information of the sequential fields written in the memory included in the compressor 66 at twice the speed at the time of writing. FIG. 6D shows one field period T at the time of 1/2 speed reproduction, which is read out from the compressor 66 with a delay of about T period with respect to the writing of the information for each field sequentially and time-compressed to 1/2. This is information for each one field. At this time, in the compressor 66, the above-mentioned one-field period T
Information for each field is read out and output continuously for two field periods. As a result, the information F1, F2, F3, F4, etc., for each field are output successively for two field periods, as shown alternately by the solid line part and the dotted line part in FIG. 6 (d).

That is, the information F1 and F1 for each field which coincides with the original one field period T at the time of recording.
2, F3, F4, etc. are sequentially 2 fields (1 frame)
Since the information of each minute is composed and output, there is no noise at all, and all recorded fields are reproduced.
/ 2x speed reproduction can be realized.

The capacity of the memory included in the compressor 66 is, at most, data (for example, F1 data) obtained in the two-field period 2.T at the output of the selector 65 in FIG. 6C. If the memory has twice the capacity of the above, a normal compression operation can be performed without the writing and reading for the compression overlapping in the same memory area.

In recording the first and second information, the first input to the digital input terminal 50 is performed.
The information and the second information may be information compressed by a high-efficiency encoder for reducing a recording data rate not shown in FIG. In this case, the digital data and the 1st information relating to the first information output to the digital data output terminal 60 during the normal speed reproduction of the first and second information are output.
Digital data output from the compressor 66 during / 2 (1 / r) double-speed reproduction may be decoded by a high-efficiency decoder (not shown).

Further, the above-described high-efficiency coding may be performed in the encoder 51 of FIG. In this case, the decoder 61 of FIG. 1 preferably performs high-efficiency decoding both at the time of normal speed reproduction of the first and second information and at the time of 1/2 (1 / r) double speed reproduction of the first information. In addition, in 1/2 speed reproduction of the first information, digital data output from the compressor 66 may be decoded by a high efficiency decoder (not shown).

Embodiment 2 FIG. 1/1 of the first information of the first embodiment.
In the process at the double speed reproduction, all the recorded fields have been reproduced. However, only the odd or even field constituting one frame is used, and the 1st information is reproduced at the quarter speed reproduction (1/1). (2 · r) double speed reproduction). Even in the 1/4 speed reproduction in this embodiment, the values of the head rotation speed and the tape speed are the same as those of the second embodiment.
And the same value as in the case of the recording or the normal speed reproduction of the first information, in other words, 1 / 2.R and 1 / 2.V, which are 1/2 times the value at the time of recording the first information. FIG.
(b) is the same as the decoder output of FIG. 1 shown in FIG. 6 (b). In FIG. 7 (b), F1, F2, F3, F4, F
.., F6, F7, F8, F9, F10,... Are information in units of one field for each two-field period 2.T which is twice as long as the recording time, and F1 is the information in FIG. The two-channel reproduced signals D1A, D1B, D2A,
And D2B, and F2 is D3A, D3B, D4
From A and D4B, F3 is D5A, D5B, D6A,
And D6B, F4 is D7, D7B, D8A, and D
8B is a field synthesized from 8B. Here, F1, F3, F5 and the like belong to odd fields, and F2, F4 and F6 belong to even fields.

The output of the decoder shown in FIG. 7 (b) is input to the selector 65, and as shown in FIG. 7 (c), for example, F1, F3, F5
After only odd-numbered fields are selected, for example, a compressor 66 composed of a field memory
Time compressed. Time compression of 1/2 can be easily realized, for example, by reading the information of the sequential fields written in the memory included in the compressor 66 at twice the speed at the time of writing. FIG. 7D shows the state of the compressor 66.
This is information in a unit of one field for each one-field period T at the time of １ ／ × speed reproduction, which is time-compressed to １ ／ and output. At this time, the compressor 66 reads out and outputs the information F1, F3, F5, etc. in the unit of one field for each one-field period T, which has been time-compressed by half, for four consecutive field periods. As a result, FIG.
As shown alternately by the solid line portion and the dotted line portion, the information F1, F3, F5, etc., for each field are successively output for four field periods.

That is, information F1 and F1 for each field that match the original one-field period T during recording.
3, F5, etc. are sequentially formed as information for four fields (two frames), so that the noise-free quarter-speed reproduction consisting of one of the fields constituting one recorded frame is completely free. Can be realized.

In the second embodiment, the capacity of the memory included in the compressor 66 is at most the data obtained in the two-field period 2.T at the output of the selector 65 in FIG. , F1), the write operation and the read operation for the compression do not overlap in the same memory area, and a normal compression operation can be performed.

The fields used in the 1/4 speed reproduction are the even field F selected by the selector 65.
2, F4, F6, F8 and the like. further,
A configuration in which odd fields and even fields are mixed may be employed.

The operation of recording the first information and the second information or reproducing at the normal speed in the second embodiment is the same as that in the first embodiment, and the description is omitted here.

In recording the first and second information, the first information input to the digital input terminal 50 is recorded.
The information and the second information may be information compressed by a high-efficiency encoder for reducing a recording data rate not shown in FIG. In this case, the digital data and the 1st information relating to the first information output to the digital data output terminal 60 during the normal speed reproduction of the first and second information are output.
Digital data output from the compressor 66 during / 4 × speed reproduction may be decoded by a high-efficiency decoder (not shown).

Further, the above-described high-efficiency encoding may be performed in the encoder 51 of FIG. In this case, both at the time of the normal speed reproduction of the first and second information and at the time of the quarter speed reproduction of the first information, FIG.
It is preferable to perform high-efficiency decoding by the decoder 61. The first
In 1/4 speed reproduction of information, digital data output from the compressor 66 may be decoded by a high-efficiency decoder (not shown).

In the first and second embodiments, the case where the information amount of the second information is 1/2 of that of the first information has been described. However, the present invention is not limited to this. The present embodiment can be applied to the information amount of r. In other words, in the recording of the second information or the normal speed reproduction, the head rotation speed and the tape speed may be set to 1 / r respectively when recording the first information or reproducing at the normal speed. Further, if the head rotation speed and the tape speed are the same as those at the time of recording the second information or at the time of normal speed reproduction, the 1 / r multiple speed reproduction or 1-time reproduction of the first information described in the first and second embodiments will be described. / (2 · r) double speed reproduction can be realized.

In the first and second embodiments, recording and reproduction are performed on two channels. However, the number of channels is not limited to two. Can be applied. Furthermore, in the first and second embodiments, the time required for one rotation of the drum in the recording of the first information or in the normal speed reproduction is described as being the same as the one-field period T. It is not limited to being.

In the first and second embodiments, a digital VTR in which recording is performed digitally has been described. However, the same concept as in the first and second embodiments can be applied to an analog VTR. .

[0040]

As described above, according to the present invention, the predetermined
A predetermined number of rotating drums
A recording medium that runs at a predetermined running speed by scanning the head
The first information is recorded or reproduced at normal speed on the body,
1 / r (r: a positive number greater than 1) of the predetermined drum rotation speed
The predetermined number of heads provided on the rotating rotating drum
Travel at 1 / r of the predetermined traveling speed.
About 1 / r of the first information on the recording medium
Record or reproduce at normal speed the second information consisting of
1 / r of the specified drum rotation speed (r: a positive number greater than 1)
The predetermined number of heads provided on the rotating drum
Travel at 1 / r of the predetermined travel speed
The first information recorded on the recording medium
In the magnetic recording / reproducing apparatus for reproducing at / r double speed, the first
At the time of 1 / r double speed reproduction of information, the
Time axis of information of one field to be reproduced next is reduced to 1 / r
The playback information for each field obtained by compression is
At least the first information
No noise at 1 / r speed playback of
Complete 1 / r where all recorded fields are reproduced
Double speed playback can be realized.

Further , according to the present invention, the predetermined drum rotation
Of a certain number of heads provided on a rotating drum
On a recording medium traveling at a predetermined traveling speed by scanning,
The first information is recorded or reproduced at normal speed, and the
Rotate at 1 / r (r: a positive number greater than 1)
For scanning of the predetermined number of heads provided on the rotating drum
Therefore, the above-mentioned travel at 1 / r of the predetermined travel speed is performed.
On the recording medium, an information amount of about 1 / r of the first information is formed.
The second information is recorded or reproduced at normal speed, and the predetermined
Rotate at 1 / r (r: positive number greater than 1) of ram rotation speed
Scanning of the predetermined number of heads provided on the rotating drum
By the above, traveling at 1 / r of the predetermined traveling speed
The first information recorded on the recording medium is 1 / (2 ·
r) In the magnetic recording / reproducing apparatus for performing double-speed reproduction, the first
During 1 / (2 · r) double speed playback of information, the r field period
In one field that is sequentially reproduced every interval, one field
Select one of the fields that make up the frame
Then, for each field obtained by compressing the time axis to 1 / r
Since the playback information is used continuously for 2r fields,
At least 1 / (2 · r) double speed reproduction of the first information
And one of the frames constituting one recorded frame
Complete 1 / field-free, completely noise-free
(2 · r) double speed reproduction can be realized.

[0042]

[Brief description of the drawings]

FIG. 1 is a block diagram for explaining signal processing during recording and reproduction according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a track trace state in recording of first information or normal speed reproduction for describing an embodiment of the present invention.

FIG. 3 is a diagram showing a timing chart in the case of recording first and second information for explaining the embodiment of the present invention.

FIG. 4 is a diagram illustrating a track trace state in recording of second information or normal speed reproduction for explaining an embodiment of the present invention.

FIG. 5 is a diagram showing a timing chart of a demodulator output signal at the time of 1/2 speed reproduction and 1/4 time speed reproduction of the first information in the first and second embodiments of the present invention.

FIG. 6 shows 1 / first information in Embodiment 1 of the present invention.
FIG. 3 is a diagram showing a timing chart of a 2 × speed reproduction signal.

FIG. 7 shows 1/1/1 of first information in Embodiment 2 of the present invention.
FIG. 4 is a diagram showing a timing chart of a quadruple speed reproduction signal.

FIG. 8 is a diagram illustrating an operation at the time of recording and reproduction in a conventional VTR.

[Explanation of symbols]

 1 Head scanning direction 2 Tape running direction 50 Digital data input terminal 51 Encoder 52 Modulator 57 Rotating drum 58 Tape 60 Digital data output terminal 61 Decoder 62 Demodulator 65 Selector 66 Compressor 71A head 71B head 72A head 72B head 81A Recording track 81B recording track 82A recording track 82B recording track 91A recording track 91B recording track 92A recording track 92B recording track

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toru Inoue 1 Baba Zoshosho, Nagaokakyo-shi Inside Mitsubishi Electric Corporation's Electronic Product Development Laboratory (56) References JP-A-2-195576 (JP, A) (58) Survey Field (Int.Cl. ⁷ , DB name) G11B 5/09 H04N 5 / 782,5 / 783

Claims (2)

(57) [Claims] 1. A method for recording first information or reproducing at a normal speed on a recording medium running at a predetermined running speed by scanning a predetermined number of heads provided on a rotating drum rotating at a predetermined drum rotation speed; The recording medium running at 1 / r of the predetermined running speed by scanning of the predetermined number of heads provided on the rotating drum rotating at 1 / r of the drum rotation speed (r: a positive number greater than 1). Above, approximately 1 / r of the first information
Recording or reproducing at a normal speed the second information composed of the information amount of the predetermined number of heads provided on the rotating drum rotating at 1 / r (r: a positive number greater than 1) of the predetermined drum rotation speed. by scanning a magnetic recording and reproducing apparatus for reproducing the recording medium on the 1 / r speed the first information recorded in running at 1 / r of said predetermined running speed, 1 / r speed of the first information During playback, r field period
The information of one field that is sequentially reproduced every interval is 1 / r
The playback information for each field obtained by compressing the time axis to
Magnetic field characterized by being used continuously for r field periods
Recording and playback device . 2. A rotary drum rotating at a predetermined drum rotation speed.
A predetermined traveling speed is obtained by scanning a predetermined number of heads provided above.
The first information is recorded or transmitted on a recording medium
Regenerate at normal speed, and perform 1 / r (r: 1
Number) provided on the rotating drum rotating in the predetermined number
By scanning the head, 1 / r of the predetermined traveling speed
On the running recording medium, approximately 1 / r of the first information
Recording or normal speed reproduction of the second information having the information amount of
And, wherein the predetermined drum rotation speed of 1 / r (r: 1 more positive
Number) provided on the rotating drum rotating in the predetermined number
By scanning the head, 1 / r of the predetermined traveling speed
The first information recorded on the traveling recording medium
Recording / reproducing apparatus for reproducing 1 / (2 · r) double speed
Te, wherein the 1 / (2 · r) at double speed reproduction of the first information, r Fi
One field that is played back sequentially every field period
One of the fields constituting one frame
1 field obtained by compressing the time axis to 1 / r
Playback information for each field is used continuously for 2 · r field periods
A magnetic recording / reproducing apparatus characterized by the above-mentioned.