JP2682987B2 - Information signal recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a plurality of areas on a recording medium, a plurality of types of information signals different from each other, and a plurality of types of information signals together with a recording position. The present invention relates to an information signal recording / reproducing apparatus for recording a plurality of pieces of synchronization data indicating the numerical values and reproducing the plurality of types of information signals from the recording medium. [Prior Art] Conventionally, as an information signal recording / reproducing apparatus as described above, for example, there is a video tape recorder (hereinafter referred to as VTR). In a VTR, a magnetic head attached to a rotating cylinder during recording forms a plurality of helical tracks on the magnetic tape by recording image signals diagonally to the running direction of the tape, and the helical tracks are reproduced during playback. This device restores the image signal recorded on the magnetic tape by tracing. In addition, recently, a VTR (for example, a well-known 8 mm VTR) capable of recording and reproducing a digitalized audio signal in addition to an image signal has also appeared. FIG. 2 is a diagram showing a schematic structure 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 and 4 are guard spaces G respectively.
S ₁ , GS ₂ and GS ₃ . Further, 6 is the traveling direction of the magnetic head,
Reference numeral 7 is an arrow indicating the traveling direction of the magnetic tape 8. In the conventional 8 mm VTR, when the magnetic head (not shown) traces on the magnetic tape 8 in the direction of the arrow 6 in the figure at the time of recording, the magnetic head is first switched during the period of GS ₁ 13,
Then, the PCM audio signal is recorded in the recording area 2. Then the signal is PCM supplied to the magnetic head during the GS ₂ 4
Is switched from the audio signal to the image signal, the image signal is recorded in the area 1, the formation of the next recording track is performed in the same manner after further passing through the GS ₃ 5. In the 8mm VTR, the above guard space GS ₁ 3, GS ₂ 4,
GS ₃ 5 is provided in order to absorb the error of the switching timing of the magnetic head. [Problems to be Solved by the Invention] However, recently, there is a tendency to perform high-density recording in which as many information signals as possible are recorded on a magnetic tape. Especially in a digital VTR that digitally records an image and an audio signal, the amount of information to be recorded is large, so it is advantageous that the recording area on the magnetic tape is as wide as possible. Need to reduce. However, if the guard space is reduced, the ability to absorb the error in the switching timing of the magnetic head is reduced, and for example, it is written in the image signal recording area at the time of after-recording (after recording) of the PCM audio signal, etc. When reproducing the magnetic tape recorded by the device, since the switching of the magnetic head is slightly different depending on the device, there is a problem that the switching cannot be performed properly and the correct reproduction cannot be performed. The present invention has been made in view of the above problems, and a plurality of types reproduced from a recording medium in which a plurality of types of information signals and a plurality of synchronization data each of which indicates a numerical value corresponding to a recording position are recorded. The switching timing of the information signal of
It is an object of the present invention to provide an information signal recording / reproducing apparatus capable of accurately rewriting an information signal by using a numerical value corresponding to the recording position indicated by the synchronous data, with high accuracy. [Means for Solving the Problem] In the information signal recording / reproducing apparatus of the present invention, a plurality of types of information signals different from each other are recorded in a plurality of areas on a recording medium, and the plurality of types of information signals are respectively recorded in a recording position. In a device for recording a plurality of synchronization data indicating corresponding numerical values and reproducing the plurality of types of information signals from the recording medium, the plurality of types of information signals and the plurality of synchronization data from the recording medium. Reproducing means for reproducing the data, a restoring means for restoring a numerical value corresponding to the recording position indicated by the plurality of synchronization data reproduced by the reproducing means, and a recording position indicated by the plurality of synchronization data restored by the restoring means. On the recording medium, detecting means for detecting the switching timing of a plurality of types of information signals reproduced by the reproducing means by using a numerical value corresponding to Recording means for recording at least one kind of information signal, and recording operation control means for controlling the recording operation start timing in the recording means according to the timing signal from the detecting means are provided. [Operation] With the above configuration, the information signal can be rewritten with high accuracy. EXAMPLES Hereinafter, the present invention will be described using one example of the present invention. FIG. 1 is a schematic configuration diagram of a VTR to which the present invention is applied. In FIG. 1, when a recording or reproducing operation instruction signal is input to the system controller 19 from an operation unit (not shown) during a normal recording or reproducing operation, a recording operation instruction signal is input from the output terminal a of the system controller 19. Sometimes an L (low) level signal is input, and when a playback operation instruction signal is input, an H (high) level signal is a NAND gate
Supplied to 21. Further, when an after-recording recording operation instruction signal is supplied to the system controller 19 from the output terminal b of the system controller 19, an H level signal is output to the flip / flop (FF) 20, and FF20
Is designed to work. That is, at the time of normal recording or reproduction operation, since the H level signal is not output from the output terminal 6 of the system controller 19, the FF 20 does not operate, and the L level signal is supplied to one input terminal of the NAND gate 18, The NAND gate
A NAND gate 21 is supplied with an H level signal from 18.
When a recording operation instruction signal is supplied to the system controller 19 as described above, an L level signal is output from the output terminal a, and an H level signal is supplied from the NAND gate 21 to the switch 10 and the switch 10 Is connected to the H side in the drawing, the input image signal and the audio signal are digitalized in the time division multiplexing circuit 22, respectively, and further time division multiplexed to form a recording signal, and the formed recording signal In the recording signal processing circuit 11, after adding the synchronization data and the ID (index) data representing the position of the synchronization data, the signal is modulated into a signal carrier suitable for the magnetic circuit, amplified by the recording amplifier 12, and then the switch. It is recorded on the magnetic tape 8 by the magnetic head 9 via 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, and an H level signal is supplied from the NAND gate 21 to the switch 10 and the switch 10 is supplied. Is connected to the L side in the figure, 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 10. After that, reproduction signal processing circuit
14, supplied to the synchronous data detection circuit 15. It should be noted that the recording signal is added with synchronization data and ID data during recording, and in particular, the synchronization data is added to the recording signal at a predetermined ratio. In this embodiment, when the input image signal is an NTSC television signal,
100 pieces of sync data are added at equal intervals to one field of image data, and one piece of sync data is added to the head portion of the audio data corresponding to one field period. I shall. The synchronous data detection circuit 15 detects the synchronous data added as described above from the reproduction signal supplied at the time of recording,
When the synchronous data is detected, the detection signal is supplied to the counter circuit 16. Further, in the reproduction signal processing circuit 14, the supplied reproduction signal is demodulated into the original signal form and supplied to the output switching circuit 23 and the counter circuit 16. In the counter circuit 16, the ID data of the sync data detected according to the sync data detection timing in the sync data detection circuit 15 is fetched from the supplied reproduction signal,
The position of the detected synchronization data is determined. If the position of the detected synchronization data is "20" in the counter circuit 16, the counter circuit 16 outputs "10".
The counting operation is performed until the synchronous data at the position of "0" is supplied, and when the count value becomes "101", the switching timing signal is supplied to the output switching circuit 23, and the output switching circuit 23 supplies the switching timing. The reproduced signal is decoded into analog in synchronism with the signal, separated into an image signal and an audio signal, and output, and the count value of the counter circuit 16 is reset. The dubbing operation of the audio signal in this embodiment will be described below: In Fig. 1, when performing the dubbing operation, first, the dubbing operation instruction signal is supplied to the system controller 19, and the system controller 19 outputs the output terminal b. A higher H level signal is output to the FF 20, and at the same time, an H level signal is output from the output terminal a. A PG signal that switches between the H level and the L level is supplied for each field period, and an H level signal is output for each field period and supplied to the NAND gate 18. Also, as described above, the system controller. Since an H level signal is output from the output terminal a of 19, the switch
Reference numeral 10 is first connected to the L side in the drawing, the reproducing operation is performed in the same manner as described above, and the counter circuit 16 detects the switching timing of the image data and the audio data. Then, in the counter circuit 16, the switching timing signal output when the switching timing is detected is supplied to the mono-multi vibrator (MM) 17. When the switching timing signal is input, the MM17 has a high level for a period corresponding to one field of audio data.
A level signal is output, and during the period when the H level signal is being output from the FF 20, the period when the H level signal is being generated from the MM 17, that is, the recording recorded on the magnetic tape 8. During the audio data area of the signal, the switch 10 is connected to the H side in the drawing to enter the recording state, and the audio data post-recording operation is performed. In this embodiment, a case has been described as an example where two types of information signals, an image signal and an audio signal, are recorded on a magnetic tape and a new audio signal is post-recorded with respect to the recorded audio signal. However, in the examples, M.
By preparing a plurality of M.s and operating the plurality of MMs at different timings according to the value detected by the counter circuit, even when more types of information signals are recorded, Rewriting can be performed with high accuracy. Further, although the present 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 devices. [Effects of the Invention] As described above, according to the present invention, reproduction is performed from a recording medium on which a plurality of types of information signals and a plurality of synchronization data each showing a numerical value corresponding to a recording position are recorded. An information signal recording that can accurately rewrite the information signal by detecting the switching timing of a plurality of types of information signals with high accuracy by using the numerical value corresponding to the recording position indicated by the synchronization data. A playback device can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS 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 structure of a recording format of an 8 mm video recorder as a conventional example. 10 …… Switch, 15 …… Synchronous data detection circuit, 16 …… Counter circuit, 17 …… Mono multivibrator, 18,21 …… NAND gate, 19 …… System controller, 20 …… Flip flop.

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Meisuke Kakura               3-30-2 Shimomaruko, Ota-ku, Tokyo               Inside Canon Inc.                (56) References JP-A-60-237778 (JP, A)                 Actual Development Sho 61-79839 (JP, U)

Claims (1)

(57) [Claims] A plurality of types of information signals different from each other are recorded in a plurality of areas on a recording medium, and a plurality of synchronization data each of which indicates a numerical value corresponding to a recording position together with the plurality of types of information signals, and the recording is performed. In a device for reproducing the plurality of types of information signals from a medium, a reproduction unit that reproduces the plurality of types of information signals and the plurality of synchronization data from the recording medium, and the plurality of synchronization data reproduced by the reproduction unit. Restoring means for restoring the numerical value corresponding to the recording position indicated by, and a plurality of types of information signals reproduced by the reproducing means using the numerical values corresponding to the recording positions indicated by the plurality of synchronization data restored by the restoring means Detecting means for detecting the switching timing of the recording medium and outputting a timing signal; recording means for recording at least one type of information signal on the recording medium; In response to a timing signal from the means, the information signal, characterized in that it comprises a recording operation control means for controlling the recording operation start timing in the recording means recording and reproducing apparatus.