JPS63283285A - Intermittent magnetic sound and picture recording device - Google Patents

Abstract

PURPOSE:To obtain a sound recording and reproducing function also in an intermittent recording system and to attain the record and reproduce of excellent and continuous sounds by means of the small number of rotary heads by using a field memory by compressing a sound signal about a time axis in a magnetic tape stopping state and writing the signal on a magnetic tape by means of the rotary head. CONSTITUTION:A sound signal is compressed about the time axis by the memory 14 and the compressed sound signal is recorded in a sound signal recording track on the magnetic tape through the rotary head 4. A sound signal and a video signal are alternately recorded in each track pitch, said operation is repeated every intermittent sending with a prescribed time interval, and even in the intermittent sending, continuous sounds are successively recorded in a sound recording tracks. A trouble increasing video noises on the way of the intermittent sending due to the existence of the sound signal track between the video signal tracks is resolved by temporarily storing a video signal in an image field memory at its stopped state and reproducing the contents of the field memory as a video output at the time other than the field memory writing time. In case of using the image field memory, video tracks and sound tracks can be alternately formed in each track pitch only by one rotary head.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application] The present invention relates to an intermittent magnetic recording/recording device that performs long-term recording and playback by intermittent recording and is used for monitoring purposes and the like.

[Conventional technology]

In a rotating head helical scan type VTR (video tape recorder), the video signal is recorded as a still image at a rate of one sheet every few seconds by intermittent feeding of magnetic tape.
An intermittent magnetic recording/reproducing device (referred to as a time lag VTR) that performs long-time recording/reproducing of about 40 to 480 hours is widely used for monitoring purposes such as gold M [seki, etc.].

An example of this intermittent recording time lag VTR is disclosed in, for example, Japanese Patent Laid-Open No. 58-62985.

However, because the time-lag VTR records intermittently, the method of recording and reproducing audio on a linear track, which is generally used for VTR audio recording, cannot be used. It only has an audio recording and reproducing function using =7 tracks, and it was not possible to record and reproduce audio in an intermittent recording mode of about 24 to 480 hours, which is actually required for monitoring.

[The gap that the invention attempts to solve]

The conventional technology described above has the inconvenience of not being able to record audio signals using the intermittent recording method that uses a linear track for audio and repeating the running and stopping of a magnetic tape intermittently, and lacks an audio recording function. Ta.

SUMMARY OF THE INVENTION An object of the present invention is to provide an intermittent magnetic recording/recording device t which enables high-quality continuous recording and reproduction of audio information even in an intermittent recording method, has a simple configuration, and is miniaturized.

[Means for solving problems]

The above purpose is a means to compress the time axis of the audio No. 1g using a semiconductor memory even when the magnetic tape is stopped and to write it onto the magnetic tape at every Pfr construction time using a rotating video head or a separate head. This is achieved by providing video signal recording tracks and audio signal recording tracks alternately for each track pitch.

[Effect]

The audio signal is compressed on a nine-time axis by a memory, and the compressed audio number 1g is recorded on a magnetic tape as an audio signal recording track through a rotary head.

Audio signals and video signals are recorded alternately at each track pitch, and this operation is repeated every predetermined time interval (intermittent transmission), so that continuous audio can be recorded one after another on the audio recording track even with intermittent transmission. .

The problem of increased video noise during intermittent interpolation due to the creation of audio signal tracks between video signal tracks is II!
llIM! This can be solved by temporarily storing the video signal in a field memory for use in a stopped state, and then using the contents of the field memory as the reproduced video output except when loading the field memory. If a 7'C11ill image field memory is used, it is possible to alternately form video tracks and audio tracks at each track pitch using only one rotary head.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 4 is a block diagram of an intermittent magnetic recording device according to an embodiment of the present invention), in which 1 is a magnetic tape, 2 is a rotating head 3.6' for video, and a rotating head 4 for audio. Rotating drum, 5 is a capstan motor, 6 is a capstan control circuit, 7 is a drum control circuit, 8 is a servo circuit, 9 is a device for preventing aliasing noise when digitizing the input sound μ prime signal Lf'11. Low pass filter LPF,,
10 and 19 are switches that are switched by the recording mode signal part C which is 'h' during recording and %LiT during playback, and the black circle side indicates the recording mode. 11 digitizes the output AD IN of the changeover switch 10. A/D for (
12 is a gate for outputting the output data of the A/D converter to the data bus DATABUS, 13 is an address counter that specifies the address of the compression/expansion memory 14, and 15 is an intermittent magnetic converter according to the present invention. In order to perform intermittent recording and playback of video and audio signals in response to a mode command from a system control (abbreviated as system controller, not shown) of the recording/recording device, KltlJ11 signals W and CLK are sent to each section.
, 几e, the controller that supplies the mouse, 16 is D/A
(Digital to Analogue) :+
The inverter 17 is a low-pass filter LPF, 1 for removing unnecessary frequency components generated by sampling.
8 is a rotary head 4 for audio by modulating the compressed audio signal
20 is an F'M oL modulator for frequency demodulating the fc signal obtained from the Nyu audio rotary head 4 to obtain a compressed demodulated audio signal 5ICj, and 21 is an 5I ( Low-pass filters LPF3, 22 are used to prevent aliasing noise when digitizing j, and low-pass filters LPf11..23 are used to remove expensive frequency components generated by sampling. This is an inverter for inverting the control signal w=2.

2 shows a top view of the mouth 1 drum 2 of FIG. 4, and FIG. 3 shows a front view. In the embodiment of FIG. 4, the video rotary head 3.3' has a gap of the same azimuth angle, the audio rotary head 4 has a different azimuth angle from 5.3', and the 3.3'
The heads of the i161 are installed at the same height (zero step difference). Figure @4 shows a recording pattern recorded by this rotating drum 2. The magnetic tape 1 moves intermittently in the direction of the arrow 25, and the magnetic tape 1 moves intermittently in the direction of the arrow 25, with a width of one track pitch P. Recording track Vl.

■,... and audio dd recording track A, , A,...
・Or is formed.

Arrow 26 indicates the scanning direction of rotary head 5.5',4.

Next, the present invention will be explained in detail using the block diagram in FIG. 4, the recording pattern factors in FIG. 4, and the signal waveform diagram of each part in FIG. 5 shown in FIG.

Under the control of the servo circuit, the capstan control circuit 6 drives the capstan motor 5 intermittently so that a recording pattern of one track pitch is formed at predetermined time intervals, and records one image when the magnetic tape 1 is stopped. The rotating head 3 records video recording tracks V, , V, . . . (v.

(is formed after moving 2 track pitches after 1 formation)
ft is formed, and is intermittently driven in the same manner as during reproduction, and the video signal is reproduced with the image head at a four azimuth angle of 3.5' stopped on the video recording track of the magnetic tape 1.

When recording an audio signal, a low-pass filter LPF of 9 is applied to the input audio signal, recording status (1-LEC') 1''
), a digital signal (6 bits in the embodiment) is converted to VC by an A/D converter 11. The period when the read/write control signal W is 1H1 is 85.
As shown in the figure, the clock CLK is a low frequency (faL), and the audio signal passing through the gate 12 is the data bus L).
ATA BLIS' to the memory 140 predetermined reservoir. The controller sets w'2'H' at a cycle T twice that of the predetermined intermittent drive, outputs a k pulse to initialize the address counter 13, and then moves the magnetic tape 1 by one track pitch and then stops. Thereafter, the period W (T-r) remains at 8%, and the audio signal is stored in the memory 14 using the low-speed clock (faL). Then, by setting the period of τ immediately before the next intermittent drive to Wt-'l,'',
The recorded audio signal is read out from the memory, compressed in time axis, and sent to the D/A converter 16 via I) ATABUS.
Supplied via. That is, at the falling edge of W, the address counter 13 is reset and initialized again, and
Clock CLKt high frequency (falI) and compression ratio 1
Compressed 71 times. Here, compression ratio T/τ= fslI
/feL. The compressed digital audio signal is D/
It is converted into an analog signal DAOUT by the A converter 16, frequency-modulated by the modulator 18 to all F2 of LPF2, and then Dk
LV (frequency + 2!! number modulation wave) becomes changeover switch 1
9 (low state) and is supplied to the audio head 4.

)) In modulation 6, the inverted signal of W from the inverter 23 is input, and the recording current is supplied to the head 4 only during the period τ. τ is a period corresponding to one field of video, and is equal to the vertical synchronizing signal period vI/c, which is 1759.94 (seconds) in the NTSC system.

The formation of the video recording pattern and the audio recording pattern will be explained in chronological order as follows.

- When the tape is stopped, a video signal is first recorded on one recording track V by the rotary head 3, and immediately thereafter, it is driven intermittently by one track pitch (P). Thereafter, after a predetermined period of time (approximately T/2) has elapsed, the compressed audio signal is transferred to the rotating head 4.
Recorded on the audio recording track during the period τ in the figure, immediately after Vc
It is driven intermittently by one track pitch (P). Then, after passing for a predetermined period of time (approximately T/2), the rotating head 3
11j! is recorded at the same azimuth angle on V, and in the same manner as described above, it is recorded every 1 track pitch! 1! No. I recording tracks and audio signal recording tracks are formed alternately.

Next, using the waveform diagram of each part during audio reproduction shown in FIG. 6, it will be explained how the compressed audio signal is expanded and restored to the original continuous audio.

Since this is the time of reproduction, Ic is % L'. rotating head 4
4A, the top, the compressed audio signal from the head passes through the changeover switch 19 (white circle 9111) and is frequency demodulated by the anti-demodulator 20 to the baseband 5I (
The signal passes through the filter, LPF, and changeover switch 10 and is converted into a digital signal by an A/D converter 11. When head 4 or A is on top, R from controller 15
At the same time as the e-hals is output and the address counter 13 is initialized, the period of τ w'? :'h, the compressed audio signal passing through the gate 12 passes through DATABLI8 and is stored in the memory 14 using the high-speed clock f8m (clock CLK is W
is in the state of high-speed clock fBH because it is H1), and one field is stored. Immediately after that (when W becomes % La), the 611 tape 1 is moved by one track pitch P by intermittent driving.

Re Hals is fully output and read from the first address using the low-speed clock feb (because W is s1.a), l)A
'l'ABLIS=km, and the expanded and restored audio signal is input to the D/A converter 16. At the same time, when W changes from 1F1' to 'L1', it is intermittently driven by one track pitch P to move to the position 3 in FIG. 4, and the video signal is reproduced by the head 6.5'. By repeating the above operation at a cycle of T, the 8E expanded audio A is expanded as shown by DAUUT in FIG. 6, and the original recorded audio signal is continuously restored. The DAULJT signal passes through the LPB'4, and unnecessary signals during the period τ being stored in the memory 14 are removed, and an output signal (JLJT) is output.

In this embodiment, a VH8 type 2-hour recording mode tape is used to record compressed audio at 4 (second) intervals, and the pressure rope ratio is 240 times, making it possible to record for 480 hours. Also, the missing period while filling the memory 14 is 1159.94 (seconds) out of 4 (seconds), which is not a problem.Also, the timing of intermittent driving during recording and playback of video and audio as explained above is not a problem. is an example.

Next, as a second embodiment, a case will be described in which a predetermined difference is provided between the video rotary head and the audio rotary head. 7th
FIG. 8 shows a top view of the rotary drum 2 of the second embodiment, FIG. 8 shows a front view, and m9(2) shows the recording pattern factor. Here, the recording patterns A1 and A are all shown in FIG. 4 (although they are not the same, the same symbols are used for convenience of explanation as they are similar to those in FIG. 4 (the same applies hereafter). When using a head configured as shown in FIG.
A, , V, , A, ... were recorded alternately, but Vl and A were recorded in a stopped state, and then V, A, and V, all recorded with intermittent recording equivalent to 2 track pitch 2P. 5 actions can be performed. By doing this, although the small recording pattern remains the same, it is possible to simultaneously read out the video signal v1 even during KAlt-reading during playback, and it is possible to eliminate the omission of instantaneous video.

Next, as a fifth embodiment, a case will be described in which a two-head configuration is used and one field memory for one dormitory is used.

In order to simplify the configuration and reduce costs, it is desirable that the number of heads of K is small. Figure 40 shows the rotary drum 2 of the m6 embodiment.
FIG. 41 shows a front view, and FIG. 42 shows a recording pattern diagram.If the video rotary heads 5 and 6' have the same azimuth, head 3 is shared as the audio head, and If the timing control of intermittent drive during recording and reproduction is performed in the same manner as in the fourth embodiment, the operation will be similar to that in y. The difference is that the recording azimuth angles of Vl, v2 and A, , A, are the same. In this case, if the head width is narrowed and a guard band is provided between each recording track, the influence of crosstalk can be almost ignored.

Furthermore, when the azimuth angle [' of the rotary head 3.3' is made different, the intermittent drive timing control during recording is exactly the same, and the formed recording pattern diagram (FIG. 42) can be exactly the same as FIG. 4. However, during playback, for example, video recording field V
+t'' can be reproduced with head 5, but since the azimuth is different in head 3', a dropout occurs for each field. This problem can be solved by providing a video signal reproducing circuit shown in FIG.

In Fig. 43, 31 is a video signal processing circuit, and the rack is an A/
D converter, 33 is 1 field meter for projection stage% IJ
, 34 is a D/A converter, 55 is a video writing (changeover switch that becomes the black circle side when the M number WV is h'', 66 is 1
This is a controller that outputs addresses No. 15 ADR, :WV to control the field memory 33 and changeover switch 35. The operation of this circuit is shown in Figure 8g13.
This will be explained using Figure 44 of the No. g Sakata map.

When playing Eirin No. 1g, for example, when reproducing video recording field 1, the output 5IGV of No. 16 processing circuit is missing one field at a time, as shown in FIG.

Therefore, after stopping the intermittent drive, as shown in FIG. 44, WV is set to "H" for one field period and one field of video 1g digitized by the A/D converter 32 is written into the one field memory 33, and then returns to Wvi'L', reads the video signal from the 1-field memory, and then returns to Wvi'L'.
/A converter and a changeover switch to obtain the continuous nine missing video signals shown on VUUT.

Note that while 5I (jV) is being written to the total 1 field memory 35, the changeover switch 35 outputs 5IGVt- to prevent omission.

As a fourth embodiment, it will be shown that the present invention can be constructed with only one oral transmission head by using the one-field memory described above. FIG. 45 shows a top view of the rotary drum 2 of the fourth embodiment, FIG. 46 shows a front view, and FIG. 47 shows a recording pattern diagram.

If the head 3 is shared as the audio head and the timing system of intermittent drive during recording is performed as in the embodiment shown in FIG.
The operation is the same as the ``S'', and the recording pattern is the same except that the azimuth angles of the video and audio tracks are the same. In other words ■
Immediately after creating 1 pattern, after running intermittently equivalent to 1 track pitch, after a predetermined period, immediately after creating v1 pattern, 1
All you have to do is run the track in alternating pitches. During playback, the 1-field memo Vt in Figure 45 is used, and the operation is the same as in the example when the azimuth angles of V, , V, and A, , A are different in Figure 42. The video signal can be a continuous signal.

Furthermore, even for the same one head, as shown in the top view in Figure 48 and the front view in Figure 49, the diameter of the rotating drum is set to 1/n (n is a positive number), and the magnetic tape is wound so that the corner is Double and
If the number of revolutions of the rotating drum is multiplied by n to form a video and audio recording track, the drum diameter and winding shown in Fig. 47 can form a recording pattern that is exactly the same as the normal format before changing the corner. The present invention can be implemented using only one head and a small diameter cylinder, and intermittent magnetic recording of an ultra-small camera-integrated VTR can be realized.

〔Effect of the invention〕

As explained above, according to the present invention, when the magnetic tape is stopped, the time axis of the audio 100 is compressed and transferred to the rotating head.
Since it is written on the magnetic tape, it becomes possible to perform audio recording and playback functions that were not possible before, and also prevents loss of image signals due to intermittent movement of the tape. , it becomes possible to record and reproduce continuous audio with a small number of rotating heads.

[Brief explanation of drawings]

FIG. 4 is a block diagram of an intermittent magnetic recording device according to an embodiment of the present invention, FIG. 2 is a top view of the rotating drum of FIG. 4,
Fig. 6 is a front view of the rotating drum shown in Fig. 4, Fig. 4 is a recording pattern diagram by the rotating head shown in Fig. 2, Fig. 5 is a signal waveform diagram of each part during recording, and Fig. 6 is a diagram of each part during playback. The signal waveform diagram, Figures 7 and 8 are the top view and front view of the rotating drum according to the second *m example, respectively. A top view and a front view of the rotating drum according to the third embodiment, respectively, and FIG.
Figure 45 is a block diagram of a video signal circuit using field memo Vt, Figure 44 is a signal waveform diagram of each part of Figure 43, and Figures 15 and 46 are respectively for the fourth embodiment. Top and front views of the rotating drum according to No. 47
The figure is a recording pattern diagram of FIG. 45, and FIGS. 48 and 49 are a top view and a plan view, respectively, in the case of a small-diameter rotating drum. 2... Rotating drum, 5.6'... Image head, 4
...Audio head, 5...Capstan motor, ?
, 17.21°22...Low pass filter, 11.
...A/D converter, 16...D/A converter,
14...Memory, 15...Con No. 1 Illustration 2 Ward No. 3 Drawing and construction drawing Construction drawing broom + Drawing No. S drawing DT<V &----←←-Kuichi No. 6 Drawing 7 Drawing name 8 Figure 89 Figure collection 10 Figure Island 11 Drawing surface 1 Front view broom I2 Figure collection 13 Surface inspection 14- Figure LJY Yi Reiji! 'Island 15 Figure Collection! 6 diagram king f1 side ball frta island 17 diagram

Claims (1)

[Scope of Claims] 1. A means for intermittently repeating running and stopping of the magnetic tape at predetermined time intervals, and at least one rotary head for recording video signals, which records one field of video signals during the stop period. In an intermittent magnetic recording device having a means for recording audio signals on a magnetic tape as one video recording track, a memory for compressing and decompressing an audio signal in the time axis, and a rotary head for recording the video signal or a separate memory for compressing and expanding the audio signal in the time axis. Intermittent magnetic recording, characterized in that it has means for recording on a magnetic tape at predetermined time intervals using a rotating head, and is configured to alternately form video signal recording tracks and audio signal recording tracks at every track pitch. Device. 2. It has a field memory that temporarily stores the video signal of the recorded video signal track, the contents of which are reproduced and output, and the video signal is read intermittently from the recorded video signal track while the magnetic tape is stopped, and the field memory is 5. The intermittent magnetic recording/recording device according to claim 4, wherein the contents of the memory are updated each time. 3. A common feature is that only one rotary head is used for video signal recording and audio signal recording, and video signal recording tracks and audio signal recording tracks are alternately formed for each track pitch. An intermittent magnetic recording recording device according to claim 2. 4. The diameter of the drum equipped with a rotating head is set to 1/n,
Claim 2, characterized by having means for forming a recording pattern that is exactly the same as the normal format before changing the drum diameter and the winding angle by increasing the winding angle of the magnetic tape around the drum by n times. 6. The intermittent magnetic recording recording device according to item 5.