JPS63217572A - Recording and reproducing device for information signal - Google Patents

Abstract

PURPOSE:To accurately rewrite information signals by controlling a recording action start timing in a recording means in accordance with the switching timing signals of plural kinds of information signals from a detection means. CONSTITUTION:In case executing the after recording action of audio signals, signals of a level H are outputted to an FF20 from an output terminal (b) in a system controller 19, and the signals of the level H are simultaneously outputted from an output terminal (a). On the other hand, PG signals whose level is switched at every field period are supplied to the FF20, and the signals of the level H are supplied to a NAND gate 18 at every field period. If a switching timing is inputted, a monostable multivibrator 17 outputs the signals of the level H for the period equivalent to audio data for one field period. For this period, a switch 10 is connected to an H side, and a system becomes in a recording state, whereby the after recording action of audio data is executed on a magnetic tape 8. Thus, the information signals can accurately by rewritten.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention records different types of information signals in a plurality of areas on a recording medium in a time-sharing manner, and also records the plurality of types of information signals from the recording medium. The present invention relates to an information signal recording and reproducing device for reproducing information.

[Prior Art] Conventionally, as an information signal recording and reproducing device as described above, there is, for example, a video tape recorder (hereinafter referred to as VTR).

In a VTR, a magnetic head attached to a cylinder that rotates during recording forms a plurality of helical tracks by recording image signals on a magnetic tape diagonally with respect to the running direction of the tape. This is a device that restores image signals recorded on magnetic tape by tracing them.

Furthermore, recently, VTRs (for example, the well-known 8 mm VTR) that can record and reproduce digitized audio signals in addition to image signals have also appeared.

FIG. 2 is a diagram showing a schematic configuration of a recording format of an 8 mm VTR as a conventional example.

In FIG. 2, 1 is an image signal recording area, 2 is a PCM audio signal recording area, and 3.4.5 is a guard space GS, GS2. It is GS3. Further, 6 is an arrow indicating the traveling direction of the magnetic head, and 7 is an arrow indicating the traveling direction of the magnetic tape 8.

Conventionally, in an 8 mm VTR, when a magnetic head (not shown) traces the magnetic tape 8 in the direction of the arrow 6 in the figure during recording, the magnetic head is first switched during the period GS, 3. Subsequently, the PCM audio signal is recorded in recording area 2.

Next, the signal supplied to the magnetic head during the period G524 is P
The CM audio signal is switched to the image signal, and the area l
An image signal is recorded on the track, and after passing through G535, the next recording track is formed in the same manner.

In addition, in the 8 mm VTR, the guard space GS, 3. G524. G535 is provided to absorb errors in switching timing of the magnetic head.

[Problems to be Solved by the Invention] However, recently there has been a trend toward high-density recording in which as many information signals as possible are recorded on a magnetic tape. Particularly in digital VTRs that digitize and record image and audio signals, there is a large amount of information to be recorded, so it is advantageous to have as large a recording area as possible on the magnetic tape. need to be reduced.

However, when the guard space is reduced, the ability to absorb errors in the switching timing of the magnetic head decreases, and for example, during post-recording of PCM audio signals, data may be written into the recording area of the image signal, or other errors may occur. When reproducing a magnetic tape recorded with such an apparatus, since the switching of the magnetic head differs slightly depending on the apparatus, a problem arises in that the switching cannot be performed correctly and correct reproduction cannot be performed.

The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide an information signal recording and reproducing device that can detect switching timings of multiple types of information signals with high precision and rewrite information signals correctly. With the goal.

Means for Solving Problem E] The information signal recording and reproducing apparatus of the present invention records different types of information signals in a plurality of areas on a recording medium in a time-sharing manner,
The apparatus also includes a reproducing means for reproducing the plurality of types of information signals from the recording medium and outputting a reproduced signal, and a reproducing means for reproducing the plurality of types of information signals from the recording medium and outputting a reproduced signal; a detection means for detecting switching timing of the plurality of types of information signals using a reproduction signal and outputting a timing signal; a recording means for recording at least one type of information signal on the recording medium; and recording operation control means for controlling the recording operation start timing in the recording means according to the timing signal.

[Operation] With the above-described configuration, it is possible to rewrite the information signal with high precision.

[Example code] Hereinafter, the present invention will be explained using one embodiment of the present invention.

FIG. 1 is a schematic diagram of a VTR to which the present invention is applied.

In FIG. 1, during a normal recording or reproducing operation, when a recording or reproducing operation instruction signal is input to the system controller 19 from an operation section (not shown), the recording operation instruction signal is input from the output terminal a of the system controller 19. Sometimes the L (low) level signal is input, and when the playback operation instruction signal is input, the H (high) level signal is NAND.
The signal is supplied to the gate 21. Further, when the system controller 19 is supplied with an after-recording operation instruction signal, an H level signal is output from the output terminal of the system controller 19, and the flip-flop (F, F,) 20
is supplied to operate F, F, and 20.

In other words, during normal recording or playback operation, an H-level signal is not output from the output terminal 6 of the system controller 19, so F, F, and 20 do not operate, and one input terminal of the NAND gate 18 receives an L-level signal. is supplied,
From the NAND gate 1-18, H is applied to the NAND gate 21.
A level signal is supplied. Then, as described above, when the recording operation instruction signal is supplied to the system controller 19, an L level signal is output from the output terminal a, and the NAND
An H level signal is supplied from the gate 21 to the switch 10, the switch IO is connected to the t side in the figure, and the input image signal and audio signal are respectively digitized in the time division multiplexing circuit 22, and then A recording signal is formed by time division multiplexing, and the formed recording signal is added with synchronous data and ID (index) data representing the position of the synchronous data in the recording signal processing circuit 11, and is suitable for magnetic recording. After being amplified by a recording amplifier 12, the signal is recorded on a magnetic tape 8 by a magnetic head 9 via a switch 10. Further, as described above, when the reproduction operation instruction signal is supplied to the system controller 19, an H level signal is output from the output terminal a, an L level signal is supplied from the NAND gate 21 to the switch 10, and the switch 10 Connect to the L side in the diagram,
The recording signal recorded on the magnetic tape 8 is reproduced by the magnetic head 9 to obtain a reproduction signal, and the reproduction signal is amplified by the reproduction amplifier 13 via the switch IO, and then sent to the reproduction signal processing circuit 14 and the synchronization data. The signal is supplied to the detection circuit 15.

Note that synchronization data and ID data are added to the recording signal at the time of recording, and in particular, the synchronization data is added to the recording signal at a predetermined rate.

In this embodiment, when the input image signal is an NTSC television signal, 100 pieces of synchronization data are added at equal intervals to the image data for 1 field, which corresponds to the period of 1 field. It is assumed that one piece of synchronization data is added to the beginning of the audio data.

The synchronous data detection circuit 15 detects the synchronous data added as described above during recording from the supplied reproduction signal,
When synchronous data is detected, a detection signal is supplied to the counter circuit 16. In addition, the reproduced signal processing circuit 14 demodulates the supplied reproduced signal into its original signal form, and supplies it to the output switching circuit 23 and the counter circuit 16.

The counter circuit 16 takes in the ID data of the detected synchronous data from the supplied reproduction signal in accordance with the detection timing of the synchronous data in the synchronous data detection circuit 15, and determines the position of the detected synchronous data.

Now, if the position of the synchronization data detected in the counter circuit 16 is "20", the counter circuit 16 performs a counting operation until the synchronization data at the position "100" is supplied, and the count value reaches "101'". When this happens, a switching timing signal is supplied to the output switching circuit 23, and the output switching circuit 23 decodes the playback signal to analog in synchronization with the supplied switching timing signal, separates it into an image signal and an audio signal, and outputs the signals. , the count value of the counter circuit 16 is reset.

A normal recording or reproducing operation is performed in the following manner. The audio signal dubbing operation in this embodiment will be described below.

In FIG. 1, when performing post-recording operations, first,
A dubbing operation instruction signal is supplied to the system controller 19, and the system controller 19 outputs an H level signal from the output terminal to F, F, 20, and at the same time, an H level signal is output from the output terminal a. be done.

F, F, 20 have H level and L level for each field period.
A PG multiplied signal whose level is switched is supplied, and an H level signal is outputted every field period and supplied to the NAND gate 18.

Furthermore, as mentioned above, since a signal of level I is output from the output terminal a of the system controller 19, the switch IO is first connected to the L side in the figure, and the playback operation is performed in the same way as mentioned above. The counter circuit 16 detects the switching timing between image data and audio data.

Then, in the counter circuit 16, a switching timing signal outputted when the switching timing is detected is supplied to a mono-multi pie break (M, M,) 17.

When the switching timing signal is input, the M, M, 17 output an H level signal for a period corresponding to audio data for one field period, and the F, F, 20
During the period when a signal of higher H level is being output, the M9
M, 17 to I (period in which a level signal is generated,
That is, during the period of the audio data area of the recording signal recorded on the magnetic tape 8, the switch 10 is connected to the H side in the figure, and enters the recording state, so that the audio data dubbing operation is performed.

In this embodiment, two signals, an image signal and an audio signal, are used.
The explanation has been given by taking as an example a case where different types of information signals are recorded on a magnetic tape and a new audio signal is dubbing the recorded audio signal.
By preparing a plurality of M and operating the plurality of M at different timings depending on the value detected by the counter circuit, it is possible to record even more types of information signals. Information signals can be rewritten with high precision.

Further, although this embodiment shows a case where the present invention is applied to a VTR, the present invention is not limited to this, and the present invention can be applied to other types of recording/reproducing apparatuses.

〔Effect of the invention〕

As explained above, according to the present invention, there is provided an information signal recording and reproducing device that can detect the switching timing of multiple types of information signals with high precision and can rewrite the information signals correctly. I can do things.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a schematic configuration of a video tape recorder to which the present invention is applied as an embodiment of the present invention. FIG. 2 is a diagram showing a schematic configuration of a recording format of an 8 mm video recorder as a conventional example. lO・・・・・・・・・・・・・・・・・・・・・・・・・・・
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・River・・・・・・・・・Switch, 15・・・・・・・・・
・・・・・・・・・・・・・・・ Song/song rotation synchronization data detection circuit, 16・・・・・・・・・・・・・・・・・・
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...... Counter circuit, 17...
・・・・・・Song...River...Song Kaijima Multivi Break, 18.21・・・・・・・・・・・・・・・・・・
...Song...Song...NAND game
), 19・・・・・・・・・・・・・・・・・・
...Song...System Controller, 20...
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Songs, songs, flip-flops. 1-N-1

Claims (1)

[Scope of Claims] An apparatus for recording different types of information signals in a plurality of areas on a recording medium in a time division manner, and reproducing the plurality of types of information signals from the recording medium, wherein reproducing means for reproducing different types of information signals and outputting the reproduced signals; and detection for detecting switching timings of the plurality of types of information signals using the reproduced signals reproduced by the reproducing means and outputting timing signals. a recording means for recording at least one type of information signal on the recording medium; and a recording operation control means for controlling a recording operation start timing in the recording means in accordance with a timing signal from the detection means. An information signal recording and reproducing device characterized by: