JPS62129972A - Recording and reproducing device - Google Patents

Abstract

PURPOSE:To record and reproduce a video and a band-compressed sound signal on and from a recording medium by providing a switching means which switches the input and output of a sound signal selectively to plural time-base varying elements which perform band compression and expansion. CONSTITUTION:When a video signal is recorded, an optical image from an object which is incident on an image pickup element 2 through an optical system 2a is converted by the element 2 into a video signal, which is recorded on a magnetic sheet 9. Then, a reproduced video signal is displayed on a monitor 23. When a sound is recorded, the sound to be recorded is converted by a micro phone 12 into an electric signal, which is amplified by a preamplifier. Further, it is inputted to time-phase varying elements 14 and 15 through a switch S4 and a switch S5 which is switched at intervals of one horizontal scanning period. Signals which are band-compressed by the elements 14 and 15 are recorded on the sheet 9. A reproduced sound signal is band-expanded by the elements 14 and 15 and outputted as the sound from speaker 17. Thus, the video signal and band-compressed sound signal are recorded on and reproduced to the record ing medium.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a recording/reproducing apparatus for recording and reproducing an audio signal together with a video signal on a recording medium such as a magnetic sheet.

[Prior art]

Conventionally, recording and reproducing devices, such as video disc recorders and video sheet recorders, use so-called rotating recording media such as optical discs or magnetic sheets, to which composite video signals obtained through a television tuner or video camera are recorded. , recording is performed while forming an annular recording track, and this is particularly suitable for recording still images. The video signal recorded in this way is played back by a playback device.For example, by connecting a television receiver, it is possible to display a still image of the signal, or by connecting a printer to create a hard copy. Alternatively, it is also possible to transmit using facsimile.

By the way, the above-mentioned recording medium is capable of recording a band-compressed audio signal, which is different from the video signal.

Therefore, for example, it becomes possible to record a band-compressed audio signal on a part of the recording medium, and when playing back, re-expand the audio signal and play it back together with the related video signal. It is now possible to reproduce still images.

However, conventional recording and reproducing devices require A/J) and D/A conversion when compressing and expanding audio bands, and have many circuit components, making them expensive. .

〔the purpose〕

This invention was made by paying attention to the above problems, and A/
D. It is an object of the present invention to provide a recording/reproducing device capable of compressing and expanding an audio band with a simple circuit configuration without performing D/A conversion.

〔Example〕

Hereinafter, the present invention will be explained with reference to an example in which the present invention is applied to a still video recording and reproducing means. However, the citation of the following example is not intended to limit the scope of the present invention in any way, and the present invention is covered by the above-mentioned patent claims. Changes may be made as appropriate within the range description.

FIG. 1 is a block diagram showing an embodiment in which the present invention is applied to a still video recording and reproducing apparatus.

In the figure, 1 is the system controller (hereinafter referred to as CPU).
It is abbreviated as ), 2 is C for capturing an optical image from the optical system 2a.
An image sensor 3 such as a CD performs predetermined signal processing on the video signal from the image sensor 2, and generates a luminance signal Y and a color signal C.
This is a signal processing circuit that outputs a switch St.
, Sz are connected to terminal al132. 4 is a mixer connected to the switching contact side of switch S1, and 5 is an FM connected to this mixer 4 and the output side of switch S2.
The modulation circuit is connected to the terminal a3 of the switch $3 via the subsequent mute circuit 6 and recording amplifier 7. This mute circuit 6 is turned ON and OFF according to the signal from 0PUI.
F'F'. Reference numeral 8 denotes a single magnetic head as a recording/reproducing means for recording and reproducing signals on a magnetic sheet 9 as a recording medium. OlO connected to the switching contact side of the switch S3 receives signals from the CPU 1. A head moving mechanism 11 is a servo motor that rotates the magnetic sheet 9 in response to a signal from the CPU I.

Reference numeral 12 denotes a microphone that converts sound into an electrical signal (audio signal), which is connected to terminal a4 of switch S4 via amplifier 13.
It is connected to the. The switches 54i-i:a and the subsequent switch SI are connected to each other through switching contacts. 14 is the first terminal connected to the terminal b6 of this switch S6.
The time axis converting element 15 is connected to the terminal a5 of the switch S5, and the second time axis converting element S6 is a switch connected to the two time axis changing elements 14 and 15, which are switched together with the switch S6. means, and its terminal b6
The first time axis changing element 14 is connected to the terminal 86, and the second time axis changing element 14 is connected to the terminal 86.
time axis changing elements 15 are connected to each other. Further, this switch S6 is connected to a subsequent switch S7 through a switching contact. Reference numeral 16 denotes an amplifier connected to the terminal a7 of the switch S7, and its output end is connected to the terminal 1)+ of the switch SI. 17 is a speaker connected to terminal b7 of switch S7 via amplifier 18, 7a is a control input terminal of recording amplifier 7, 19 is a reproduction amplifier whose input terminal is connected to terminal b3 of switch S3,
19a is a control input terminal of the reproducing amplifier 19, and 20 is an l'M demodulation circuit connected to the output terminal of the amplifier I9, the output terminal of which is connected to the switching contact of the switch SR, 39. Further, the terminal a8 of this switch S8 is connected to the terminal b4 of the switch S4 via the amplifier 21, and the other terminal b8 is connected to the monitor 2 via the signal processing circuit 22.
Connected to 3. Reference numeral 24 denotes a dropout detection circuit (1) 0 detection circuit) for detecting dropout of the video signal outputted from the reproduction upstream 19, and the signal processing circuit 22 corrects the dropout according to this output. 25 is a standby switch connected to the power supply vCC. Further, the connection state of each of the switches 5l to 59 with each terminal is changed according to a signal from CP[Jl.

FIG. 2 is a diagram showing the magnetic sheet 9 used in this embodiment. In the figure, 9a is a center core provided at the center of the magnetic sheet 9, and has a hole 9b for coupling with a spindle of a servo motor 11 that rotates the magnetic sheet 9. T
1 to T32 are annular recording tracks on the magnetic sheet tree. For example, in the odd numbered tracks T1 to T31'l, a video signal containing well-known horizontal and vertical synchronization signals is stored.
FM recording is performed at a rate of one field per track. Furthermore, band-compressed audio signals are recorded in even-numbered trunks of tracks T1 to T30. In this embodiment, as will be described in detail later, the compressed audio signal is recorded as an FM signal with horizontal and vertical synchronization signals added, as in the case of the composite video signal. The innermost track T32 contains control information during playback, such as information about the compressed audio recording signal and video signals related to it, playback control information when one unit of audio information spans multiple tracks, and audio information. Records information related to the playback sequence. Note that this data track is not limited to a single track, but may be a plurality of tracks.

In the above configuration, when recording and reproducing video and audio, the standby switch 25 is first turned on and the rotation of the servo motor 1 is stabilized. When recording an image, a predetermined signal is output from 0PUI as a drive control means by operating an operation means (not shown), and switches SL, S2, S
The switching contacts a are connected to terminals ax, a2, and a3, respectively.

Thereafter, the optical image from the subject that enters the image sensor 2 via the optical system 2a is converted into an electrical signal (video signal) by the image sensor 2, and further processed by the signal processing circuit 3 to produce, for example, a luminance signal. Y, color difference signal C is output. The brightness signal Y from the signal processing circuit 3 is processed by the mixer 4 into 0PU
After being mixed with the synchronization signal (SYNO) output from I, the signal is F'M modulated by the FM modulation circuit 5. At the same time, the color signal C from the signal processing circuit 3 is also transmitted to the switch S2.
The signal is input to the FM modulation circuit 5 via the FM modulation circuit 5, where it is subjected to FM modulation. After that, the color signal C passes through the mute circuit 6, which is turned OFF by a signal from the CPU I, and then becomes the luminance signal Y.
The signal is mixed with the recording amplifier 1, and is further amplified by the recording amplifier 1, and recorded on the magnetic sheet 9 by the magnetic head 8. For example, one field of video signals is recorded in one trunk. .

In addition, when playing video, switch S3゜Sa,
The switching contacts of Se are terminals b3 l b81b9 respectively.
The connection will be switched to The video signal reproduced from the magnetic head 8 is then passed through the reproduction amplifier 19 to the FM demodulation circuit 2.
Furthermore, the demodulated signal from this FM demodulation circuit 20 is converted into an NTSO signal by a signal processing circuit 22,
This is output as a video by the monitor 23.

Next, when recording audio, the magnetic head 8 is moved to a new track by the head moving mechanism 10, and further,
Switches S+, Sa, S4 . 37 is terminal b+
, a:+, a4, and a7, respectively. After the sound to be recorded is converted into an electrical signal by the microphone 12, it is amplified by the preamplifier 13, and then the switch S4 and IH (one horizontal scanning period) are used.
The first and second time axis changing elements 14 and 15 are operated manually via a switch S6 which is switched at each time. The time axis changing elements 14 and 15 are formed of delay lines (for example, VilHOOJ), and recording is performed during each effective horizontal scanning period, and normally the IH when the audio signal is sampled at a frequency of about 14 MHz. capacity, 780b mouth
It has a certain capacity. In addition, this time axis changing element 1
5.16 is driven at a speed according to the drive pulse. The drive pulses vary depending on the number of phases of the time axis changing elements 15 and 16, but in the case of this embodiment, the drive pulses are the above-mentioned drive pulses ra, JZ+b.

These are represented by g62a and $2b.

Here, assuming that the switch S5 is initially connected to the terminal b6, the audio signal sent out via the preamplifier 13 and the switch S4 is transferred to the first time axis changing element 14 which is driven in accordance with the drive pulser 18. You can input it to .

At this time, as the drive pulse lra, a frequency of about 1/1000 of, for example, 14 MHz, the sampling frequency for setting the capacitance of each time axis changing element 14, 15 as described above, that is, about 14 KHz is used. As a result, assuming that the capacity of the first time axis changing element 14 is 780 bits, an audio signal of about 55 m5ec will be accumulated in the first time axis changing element l4. Note that at this time, the switch S6 is connected to the terminal a6. When the storage in the first time axis changing element 14 is completed, the switches S5 and S6 are switched to the terminals a5 and b6, respectively, by the (3) image signal from the CPU l.
Audio signals are similarly accumulated in the second time axis changing element 15. That is, the audio signal sampled by the drive pulse S'2a having the same frequency (14 KHz) as the drive pulse φ1a is accumulated in the second time axis changing element 15. Also, during the storage operation in the second time axis changing element 15, the audio signal currently stored in the first time axis changing element 1 is driven with a frequency (14 MHz) approximately 1000 times higher than the driving pulse 01a. The pulse lZ'+b allows high-speed reading. Then, the audio signal read from the first time axis changing element 14 is transmitted to the switch S6.
) 57 to the mixer 4 via the preamplifier 16 and switch S1, where the synchronizing signal 5YNC sent from the CPUI is added, and then the FM modulation circuit 5
and supplied to the magnetic head 8 via the recording amplifier 7,
The information is recorded on the magnetic disk 9. In this case, on the magnetic disk 9, for example, as shown in FIG. 2, an 18-minute audio signal is recorded only in the recording area T11 of the trunk T1. At this time, the recording amplifier 7 is not ONL in areas other than the recording area Tu. This is terminal 7
This is done by a control signal generated by human power. On the other hand, the second
The audio signal is stored in the time axis changing element 15, and when this storage operation is completed (55 msec has passed since the connection of the switch S5 was changed to the terminal a5), the switch S5 is connected to the terminal a5. Connect to b5. Then, a drive pulse 5Zf Ia having a frequency of 14 KHz is supplied to the first time axis changing element 14 by the CPU 1. Furthermore, the audio signal of, for example, about 55 m5ec stored in the second time axis changing element 15 is processed at high speed (14 MHz) as in the case of the first time axis changing element 14 described above.
The timing is such that the data is recorded in the next area T12 (see FIG. 2) of the recording area Tu. At this time, for example, approximately 55 m5 ec has elapsed from the completion of recording to one recording area to the start of recording to the next recording area T12, during which time the magnetic disk rotates several times (in this case, 4 rotations). ) by repeating 9 or more movements in sequence for about 14 seconds (5
5msec x 240H) audio signal is band-compressed and becomes 1
recorded on the track.

In addition, if the audio signal to be recorded is for a long time (in this case, over 14 seconds), even if F
′! It is also possible to record across multiple adjacent trunks. In this case, the magnetic head 11 is moved in the radial direction by the head moving mechanism 10, but during this movement, each time axis changing element 14.1
By delaying the output timing from 5, it becomes possible to record continuous audio signals.

When reproducing audio signals from the magnetic disk 9, the switches S3, S4, S7, and S8 are connected to the terminal t.
):+, b4, bt, and a3, and the magnetic head 8 moves to a predetermined track.

Then, the reproduced audio signal is reproduced up 19, FM
Demodulator 20, switch S8, preamplifier 21 and two switches S4. First time axis changing element I via SS
The output pulses are sampled and stored by the drive pulser 1b having a frequency of, for example, about 14 MHz. When this storage operation is completed, switches Ss, Ss are connected to terminals a5. b6, and the 18-minute audio signal reproduced by the magnetic head 8 is stored in the second time axis changing element 16. Also, during this storage operation, the compressed audio signal of 18 minutes stored in the first time axis changing element 15 is 14K.
Output at low speed by Hz O drive pulse z1a, 5
This becomes a 5m5ec audio signal, which is amplified by the amplifier 18 and then output from the speaker 17 as audio. In addition, the magnetic disk will rotate under the magnetic head 3 to 4 times until all 18 minutes of audio signals are output, and during this time the next 18 minutes of audio signals are extracted. It is stored in the second time axis changing element 15. Then, when all the audio signals for 1 f-I are output σ from the first time axis changing element 14, the switches S5 r 86 are connected to the terminals b5. The connection is switched to a6, and the accumulated audio signal is 14K from the second time axis changing element 15.
It is read out by a pulse χ2b of Hz.

As a result, the 2H-th audio signal is continuously output from the speaker 7 without causing any unnatural sound.

Also, during this time, the next IH is sent to the first time axis changing element 14.
By repeating the above operation, the speaker 17 can reproduce, for example, 14 seconds of compressed audio signals.

Furthermore, noise with a period of 55 m5ec, for example, may be added to the audio signal reproduced by the above embodiment, and a buzz sound of approximately 20 Hz may be generated.
This can be easily reduced by providing a pre-hold circuit in front of the M demodulator 20 to sample and hold the final value of the IH audio signal to smoothly demodulate the audio.

In addition, in the above embodiment, two time axis changing elements 1
Although the case where 4.15 is used is shown, it is also possible to use two or more time axis changing elements. In addition, although a single magnetic head 8 was used to record and reproduce images and audio while switching between them, it is also possible to record and reproduce images and audio using separate magnetic heads and circuits. .

In the above embodiment, a case where a synchronization signal is added to an audio signal is shown, but the present invention is particularly applicable to a case where a synchronization signal is not added, and the present invention is also applicable to a case where a synchronization signal is not added to an audio signal. The present invention can be applied not only to recording and reproducing audio signals input from a microphone, but also to recording and reproducing video and audio signals transmitted from external sources such as a television receiver, Vi''R, and video disk.

〔effect〕

As explained above, according to the present invention, it is possible to perform audio recording and playback by compressing and expanding the band without performing A/D and D/A conversion, which are essential for conventional devices. At the same time, it is possible to significantly reduce the number of parts, which has the effect of reducing costs.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the invention, and FIG. 2 is a diagram showing a magnetic sheet used in the embodiment of the invention. 1・・・・・・・・・・・・CPU 9・・・・・・・・・Magnetic sheet 14・・・・・・
...First time axis changing element 15...
Second time axis changing element Fig. 2

Claims (3)

[Claims] (1) A plurality of time axis changing elements that perform band compression and expansion by changing the time axis of an input signal, a switching means that selectively switches input and output of audio signals in each time axis changing element, and a recording medium. 1. A recording and reproducing device comprising a recording and reproducing means for recording and reproducing video and band-compressed audio signals. (2) The recording and reproducing apparatus according to claim 1, characterized in that it includes two time axis changing elements. (3) The recording and reproducing apparatus according to claim 1 or 2, wherein the time axis changing element is composed of a CCD.