JPS63133355A - Information signal recording system and information signal recording medium - Google Patents

Abstract

PURPOSE:To attain most video signals to be recorded without any modification by recording a video signal and an audio signal simultaneously after a level of a prescribed frequency part including a frequency common band of the video signal so as to facilitate to make a luminance signal used in a broad band. CONSTITUTION:A video signal being the result of common band multiplex to a chrominance carrier signal obtained by applying orthogonal biphase modulation to a chrominance subcarrier of 2.56MHz by means of two kinds of color difference signals and a luminance signal subject to broad band processing by the frequency interleaving method is supplied to an input terminal 1. The signal is supplied to a noise attenuation filter 2 and an LPF 3. The luminance signal level giving an adverse effect as a noise to a sound FM signal with the noise attenuation filter 2 is attenuated by the filter 2. Then a noise reduction filter 2 attenuates a luminance signal level giving adverse effect as noise onto an audio FM signal. Only the luminance signal subject to broad band processing is obtained by an LPF 3. The video signal passing through the filter 2 and the LPF 3 is inputted to a variable attenuation circuit 4, where the radio of summation is changed and the result is amplified by amplifiers 5, 6. Moreover, a BPF 7 passes through the audio frequency band giving adverse effect onto the audio FM signal in the video signal, the signal of the said frequency band is smoothed (8) and fed to a slider of the circuit 4 as a control signal, and the result is added (9) in the output of the amplifiers 5, 6 as the output.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to an information signal recording method and an information signal recording medium, and particularly relates to an information signal recording method and a video signal recording method for simultaneously recording a video signal and an audio signal on a recording medium. The present invention relates to an information signal recording medium on which an audio signal and an audio signal are simultaneously recorded.

(Prior Art) Various multiplexing means are used when simultaneously recording a video signal and an audio signal on a recording medium. Conventionally, a band-limited luminance signal and a low-frequency conversion carrier color signal are Band-sharing multiplexing is performed on the high frequency part of the band-limited luminance signal, and the frequency of this band-sharing multiplexed signal is modified using an audio signal on a carrier wave whose frequency is higher than the upper limit frequency of the luminance signal. A method in which the FM audio signal obtained by FJ4 (FM) is frequency-division multiplexed, and the FM signal obtained by frequency-modulating the - carrier wave with this frequency-division multiplexed signal is recorded on a recording medium. There are recording media.

According to such a recording method and recording medium, even if the distortion in the transmission system is relatively large, due to the single carrier characteristic, the luminance signal and the Wi transmission white signal can be recorded without causing beat disturbance in the demodulated video signal. In addition to being able to record two or more channels of audio signals on the same track, it also has various other excellent features.

For this reason, capacitance change reading detection type video discs called VHD (registered trademark) recorded using such an information signal recording method are currently in practical use and are widely used. In addition, there is also a reflected light type video disk in which information signals recorded on a recording medium are read and detected by reflecting a laser beam.

FIG. 4(a) is a diagram showing the frequency spectrum of the above-mentioned VHD system information signal. As shown in the figure, the video signal includes a luminance signal with a band of 3.1MlI2 or more, a color subcarrier of 2.56 MH7 (162,5fH; where fH is the horizontal scanning frequency), and a color signal with a bandwidth of ±500kllz. , are superimposed while maintaining the frequency interleaving relationship.

Two channels of audio signals each have two carrier waves,
3.43 MHz (217,75f+) and 3.7
3 MH2 (237, 25f H) and frequency modification "A (
The maximum deviation is ±75 kllz) and superimposed on the video signal. Furthermore, this composite signal is frequency-modulated using one carrier wave and then recorded on the disk.

Note that FIG. 4(b) is a diagram showing the frequency spectrum of the information signal of the NTSC system, and clarifies the correspondence with FIG. 4(a).

FIG. 5 is a diagram showing the frequency spectrum of a frequency-modulated information signal recorded on the above-mentioned Vl-1[) system video disc. As shown in Figure 4 (
When the signal shown in a> is frequency modulated, the frequency shift amount is from the synchronization signal (-4018E) to the white peak (+1001) with reference to the video signal pedestal 6.7M1lz@.
There are 1.8 MIIz up to RE), and the white side has a high frequency. Therefore, the tip of the synchronization signal is 6.1M1lZ
, the white peak is 7.9 MIIZ. Further, the relationship between the sidebands of the luminance signal, one color signal, and the audio signal, two channels, is as shown in FIG. That is, in the same figure,
It shows the range in which each sideband moves when the level of the luminance signal changes, centering on the sideband relationship at the blanking period level (6, 7 MIIZ) of the luminance signal. As can be seen from this figure, the respective sidebands do not overlap at the same time, so they are not influenced by each other.

In this way, in the recording method using the V I-I D method,
Since the audio FM signal is frequency-modulated with the same carrier wave as the video signal, audio beats, which are mainly caused by non-linear parts of the recording system or reproduction system, are less likely to appear on the screen, making it an ideal signal form. Furthermore, when one carrier wave is modulated by all the signals, it is called SCC (5inql
e Carrier Composite) method.

In addition, a tracking signal for tracking the playback button during playback, f 01: 511kllz (
32,5f H), f 112: 716kl
lZ (45,5f H), index signal f p
3: 275kllz (17,5fH) is an odd number multiple of 10 of the horizontal synchronizing signal frequency,
Also, a frequency is selected that does not overlap with the band of the first sideband of the frequency-modulated information signal.

Incidentally, FIG. 6 is a diagram showing, for reference, the frequency spectrum of a frequency-modulated information signal recorded on the above-mentioned reflected light type video disk. [Refer to "Introduction to Video Discs and CAD" edited by the Television Society of Japan, published by Coronasha Co., Ltd., November 1, 1975] (Problems to be solved by the invention) By the way, recording is done using this method. When attempting to widen the frequency band of a band-limited luminance signal among information signals for the purpose of higher resolution, an audio carrier [3,43MH2
, 3, 73MH2I (audio FM signal) band (hereinafter referred to as audio frequency band) exists, so in order to widen the frequency band of the above luminance signal, it is necessary to not record these audio FM signals from the beginning. , or move it to another frequency position.

However, with this information signal recording method, there are already a large number of recorded video discs and video disc playback devices, and in order to maintain compatibility with these existing recorded video discs, the audio FM signal It is not possible to move the recording frequency position or stop recording of the audio FM signal itself.

In addition, as mentioned above, when attempting to widen the frequency band of the band-limited luminance signal for the purpose of higher resolution, it is necessary to prevent the luminance signal from having a negative influence as noise on the audio FM signal. By using a level attenuation filter having a characteristic that allows a luminance signal having frequency characteristics as shown in FIG.
It is conceivable to always attenuate and record the level (or energy component) of the luminance signal that occupies a band including z.

However, according to this method, the luminance signal is not sufficiently separated by the luminance signal separation filter, and therefore the level of the luminance signal component occupying the audio frequency band is sufficiently low, which adversely affects the audio FM signal as noise. Even when not much is applied, the level of the audio frequency band of the luminance signal is always attenuated by the level attenuation filter having the characteristics as shown in FIG.

Furthermore, experiments have shown that in normal NTSC video signals, it is rare for the luminance signal in the audio frequency band to have a high level, and that by using a level attenuation filter with the characteristics shown in Figure 7, the luminance signal is always kept low. It has been found that the luminance signal does not have a significant negative effect on the audio signal without reducing the level of the audio frequency band of the signal.

Therefore, in view of the above-mentioned conventional technology, the present invention is capable of recording video signals in a wide band while maintaining compatibility with the existing recording method of a recorded recording medium and the recorded recording medium using this existing recording method. The object of the present invention is to provide an information signal recording method and an information signal recording medium.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides an information signal recording method in which a video signal and an audio signal are simultaneously recorded on a recording medium. In a band portion where a frequency is shared on the frequency spectrum of each of these signals, when the level (or energy component) of the frequency sharing band portion of the video signal exceeds a certain level, the frequency sharing band portion of the video signal is Provided is an information signal recording method characterized in that the video signal and the audio signal are simultaneously recorded on a recording medium after attenuating the level (or energy component) of a predetermined frequency band portion including the
Further, in an information signal recording medium in which a video signal and a g-audio signal are simultaneously recorded, a frequency sharing of the video signal is provided in a band portion where the video signal and the audio signal share a frequency on the frequency spectrum of each signal. Band level (
or energy component) exceeds a certain level, the level (or energy component) of the video signal in a predetermined frequency band portion including the frequency sharing band portion of the video signal is attenuated and recorded. The present invention provides an information signal recording medium having the following characteristics.

(Function) According to the information signal recording method having the above configuration, when the level (or energy component) of the frequency shared band portion of the video signal exceeds a certain level in the frequency shared band portion of the video signal and the audio signal, Only then, the level (or energy component) of a predetermined frequency band portion including the frequency sharing band portion of the video signal is attenuated before being recorded on a recording medium.

Further, according to the information signal recording medium having the above configuration, only when the level (or energy component) of the frequency shared band portion of the video signal exceeds a certain level in the frequency shared band portion of the video signal and the audio signal, The level (or energy component) of a predetermined frequency band portion including the frequency sharing band portion of the video signal was attenuated and recorded.

(Example) Examples of the information signal distribution system and information signal recording medium according to the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the information signal recording method according to the present invention.

In the same figure, input terminal 1 has a band of 0 to 5, 21yl.
A carrier chrominance signal obtained by quadrature two-phase modulation of a 2.56 MHz color Dllll transmission wave using two types of chrominance signals is band-sharing multiplexed using a frequency interleaving method on a wideband luminance signal of llz. A video signal is supplied. This video signal is then processed by a noise attenuation filter (F2). The signal is supplied to a low pass filter (LPF) 3.

The noise attenuation filter 2 filters the audio frequency band (approximately 3.43 MHz to 3.73 MHz) that adversely affects the Fukusei FM signal as noise, as described above, among the input video signals.
The low-pass filter 3 has a characteristic (that is, the frequency characteristic of the luminance signal shown in FIG. 7) that attenuates the level (or energy component) of the luminance signal in the band O ~5.2MIIZ
It has a characteristic of passing a broadband luminance signal.

Furthermore, a noise attenuation filter 2. The video signals that have passed through the low-pass filters 3 are supplied to the amplifier 5.6 via the two variable resistors VRI and VR2 of the variable attenuation circuit 4, respectively.

The variable attenuation circuit 4 has two variable resistors VR.

The movable contact piece of VB2 is moved and varied, and functions to change the addition ratio when the output of the noise attenuation filter 2 and the output of the low-pass filter 3 are tightened.

On the other hand, the video signal coming into the input terminal 1 is supplied to a band pass filter (BPF) 7. This bandpass filter 7 has characteristics complementary to the above-mentioned noise attenuation filter 2, that is, among the input video signals, the audio frequency band (approximately 3.43 MllZ ~3.73
The band that includes MH7) is allowed to pass through. and,
The signal that has passed through the bandpass filter 7 is smoothed by a smoothing circuit 8 and then supplied to the variable attenuation circuit 4 as a movable control signal for the two movable contact pieces.

Further, the outputs of the amplifiers 5 and 6 are respectively supplied to an adder 9 and added together, and the output of the adder 9 is outputted via an output terminal 10. Then, this output video signal passes through a known video signal recording system circuit and is recorded on various information signal recording media (for example, a video disc described later), thereby creating an information signal recording medium recorded by this recording method. is obtained.

In the above configuration, the level of the audio frequency band (approximately 3.43 Mllz to 3.73 MHz including approximately 3.43 Mllz to 3.73 MHz) of the video signal input to the input terminal 1 that adversely affects the audio FM signal as noise is bandpassed. Detected by the filter 7 and the smoothing circuit 8, two sets of variable resistors VR+ and VR2 constitute the variable attenuation circuit 4 according to the level of the detected output.
Two sets of movable contact pieces are controlled.

By controlling the movable contact piece of the variable attenuation circuit 4 in this way, the addition ratio of the output of the noise attenuation filter 2 and the output of the low-pass filter 3 can be changed, and the addition ratio of the output of the noise attenuation filter 2 and the output of the low-pass filter 3 can be changed, and the addition ratio of the output of the noise attenuation filter 2 and the output of the low-pass filter 3 can be changed. A desired video signal can be obtained from the output.

In other words, among the video signals that enter the input terminal 1, the audio frequency band (
When the level of the band (band including approximately 3.43 MHz to 3.73 Mllz) is lower than a certain level, only the output that has passed through the low-pass filter 3 is outputted via the amplifier 6 and the adder 9, and its frequency characteristics are low-pass. A variable attenuation circuit 4 is installed so that all bands passing through the filter 3 are flat.
Two sets of movable contact pieces of two sets of variable resistors VR, , VR2 constituting are controlled.

Also, among the video signals entering the input terminal 7-1, the audio F
The rich frequency band ta, which adversely affects the M signal as noise,
<3.43 Mllz ~ 3.73 MHz) When the level exceeds a certain level, the level of the output that has passed through noise attenuation filter 2 and the output that has passed through low-pass filter 3 is reduced by half of each level. is added,
The output is sent to the amplifier 6. The signal is output via the adder 9, and its frequency characteristic has a level intermediate between the level of the output that has passed through the noise attenuation filter 2 and the level of the output that has passed through the low-pass filter 3 in the audio frequency band. However, the two movable contacts of the two variable resistors VR, VR2 constituting the variable attenuation circuit 4 are controlled so that the other bands are flat.

In this way, by processing so that the level of the audio frequency band of the video signal (1-period borrowed sign) is attenuated only when the level of the audio frequency band of the video signal exceeds a certain level, it is possible to As for the video signal, it is possible to record the video signal as it is, and there is no need to always attenuate the level of the audio frequency band of the video signal (luminance signal) in order to widen the band of the luminance signal, as was the case in the past.

Furthermore, in order to increase the sharpness of the video signal, it is also possible to supply a signal that has been subjected to equalization processing in the high frequency range of the video signal as the video signal input. In this case as well, the first
The operation is similar to the circuit shown in the figure.

Next, the present invention will be described in detail regarding the case where the brightness signal of a frequency modulated video signal, for example, a video signal having a frequency spectrum as shown in FIG. 5 or 6, is widebanded and recorded on a recording medium. .

FIG. 2 is a block system diagram showing another example of the information signal recording method according to the present invention. Note that the same components in FIG. 1 of Tateyama are given the same reference numerals and their explanations are omitted.

In the figure, the input terminal 11 includes the input terminal 1 of FIG.
A video signal (modulated video signal) obtained by frequency modulating the incoming video signal is supplied to the input video signal. This modulated video signal is then supplied to a bypass filter (HPF) (or band pass filter (BPF)) 12° all-band pass filter 13.

The bypass filter (or bandpass filter) 12 filters 8 of the input modulated video signals as described above.
It has a characteristic of removing the energy component or level of the luminance signal occupying the audio frequency band (band of about 3 MHz or less) that adversely affects the voice FM signal as noise, and the all-band pass filter 13 has a wide band. It has a characteristic of passing all luminance signals.

In addition, bypass filter (or bandpass filter)
12 is the height 1i! of the reproduced signal in the disc on which the information signal is recorded and the nonlinear circuit part of the reproduction system of the information signal recorded on the disc. If there is a sideband on the side, the sideband on the low frequency side will also be reproduced, so what happens when the low frequency side of the information signal is dropped? This is provided by punching out in order to attenuate the X region side as well.

On the other hand, the modulated video signal that enters the input terminal 11 is supplied to a C-pass filter (<LPF) 14. This low-pass filter 14 has characteristics complementary to the low-frequency side characteristics of the bypass filter (or band-pass filter) 12 described above, that is, among the input modulated video signals, the audio FM signal is Voice frequency band that has a negative impact as noise (band IJ1 below approximately 3 MIIz)
It allows the passage of

The signal that has passed through this low-pass filter 14 is
After being smoothed by the smoothing circuit 8, it is supplied to the variable attenuation circuit 4 as a movable control signal for the two movable contact pieces.

Further, since the variable attenuation circuit 4 and other circuit configurations are the same as those in FIG. 1, their explanation will be omitted.

In this embodiment, the sideband of the modulated video signal is a tracking signal of a VHD recording signal having a frequency spectrum shown in FIG. Audio signal among signals,
Or VHD format.

This is to avoid affecting the digital and re-signals of reflected light video discs.

Although the characteristics of filters 12, 13, and 14 in FIG. 2 are different from those of filters 2, 3, and 7 in FIG. 1, similar effects can be obtained through the same operation as the circuit in FIG. However, in the case of this embodiment, the frequency characteristics of the video signal slightly change when the output video signal is close to the black side and when it is close to the white side.

Here, a specific circuit of the variable attenuation circuit 4 shown in FIGS. 1 and 2 will be explained.

FIG. 3 is a diagram showing an example of a specific circuit of the variable attenuation circuit 4.

As shown in the figure, the variable attenuation circuit 4 includes two variable gain amplifiers 15 and 16 and an inverting circuit 17.

The output of the noise attenuation filter 2 (or bypass filter 12) is supplied to a variable gain amplifier 15, and the output of the low pass filter 3 (or all bandpass filter 13) is supplied to a variable gain amplifier 16. The output of the smoothing circuit 8 is supplied to the variable gain amplifier 15 as its control signal, while the output of the smoothing circuit 8 has its polarity inverted via the inverting circuit 17 and is supplied to the variable gain amplifier 16 as its control signal.

As a result, the gains of the variable gain amplifiers 15 and 16 are varied in a complementary manner by control signals having different polarities, respectively.
As a result, the addition ratio between the output of the noise attenuation filter 2 (or bypass filter 12) and the output of the low-pass filter 3 (or all-band pass filter 13) is changed, and the desired video signal is output from the output of the adder 9. can get.

Next, an embodiment of the information signal recording medium according to the present invention will be described. Information signals (video signals and 8-voice signals) are then recorded on the information signal recording medium described below using the information signal recording method according to the present invention described above.

FIG. 8 is a diagram showing the shape of an embodiment of the information signal recording medium according to the present invention.

In the figure, the information signal recording medium 18 is a conductive disk, and the signal is transmitted from the outer circumference to the inner circumference for a maximum of one hour on one side.
recorded in a spiral. The starting position is diameter 24
The area from the 4sa+ position to the outer circumference 31111, 250 mm in diameter, is the part where the sensor (needle with an electrode for reading signals) descends first, which is called the lead-in section. The lead-in section has a playback time of 2 minutes and 30 seconds. Therefore, after the sensor lands on this portion with the mechanical precision of the playback device, the beginning of the program (signal), that is, the Oth page (Oth track) is searched for and playback is started. For this reason,
Playback always starts at the same position, ie from the beginning of the program.

Also, the pitch of the track where the signal is recorded is 1.35μ
m, there will be up to 54,000 lines lined up in a one-hour program. The number of revolutions is 90,000 revolutions per minute, or 15 revolutions per second. Therefore, four fields corresponding to two frames of the television signal are recorded in one rotation. exactly 9
One field is recorded every 0 degrees. For a disc containing an entire hour of programs, the end portion will have a diameter of 98.2 mm. Therefore, since the diameter starts at 244 mm and ends at 98.2 nua, one hour's worth of video signals and two channels of audio signals are recorded within a width of 73 m1. The portion after the program ends is called a program end signal section.

Signals recorded on a disk are expressed by the size of holes (bits) drilled on the surface of a flat disk, the presence or absence of holes, and the ratio of the area without holes.

Further, in the portion of the video signal (television signal) where the horizontal synchronization signal is recorded, a tracking signal is recorded so that the sensor can correctly trace one track.

This tracking signal is recorded between an information signal track on which a video signal or an audio signal is recorded and an adjacent information signal track. As shown in FIG. 9, the electrodes of the sensor accurately trace the information signal track while simultaneously reading the tracking signals recorded on both sides of the track.

In this way, even if the disk surface is flat and has no grooves for sensor tracing, it will be electrically tracked by this tracking signal.

Now, if the center of the electrode of the sensor deviates from the center of the information signal track and moves to the right due to the sensor shifting to the right, the tracking signal on the right side will be read more often than the tracking signal on the left side. Therefore, it is only necessary to control the position of the sensor so that the left and right tracking signals are always read equally. Tracking signal is flat
There are two types of tracking signals: (51tkllZ) and fl)2 (716kHz), and these two tracking signals are recorded alternately between the information signal tracks. That is, in one rotation, NJ+ is on the right side of the sensor and fD2 is on the left side, and vice versa, and fD2. is on the right side in the next rotation. fpl on the left
There will be. Therefore, indexing @f'3 (275kllz) indicating that the left and right tracking signals are swapped once per rotation is recorded superimposed on the information signal at the position where the left and right tracking signals are swapped.

Also, the width of the hole (bit) of the information signal is 0.68 to 0.9
5 μm, the depth is 0.22 to 0.38 μm, and the width of the tracking signal hole (bit) is 0.46 to 0.5
4 μm, and the depth is 0.085 to 01155 μm. The tracking signal has approximately half the width and depth of the information signal.

Further, in normal reproduction, a sensor reads the tracking signals fp+ and fp2 at the same time as the information signal, and traces according to a spiral track. At this time, the servo polarity with respect to fp+ and fD2 is changed every time fo3 is obtained once per rotation.

Furthermore, still image playback is possible by moving the sensor back one track per rotation. Note that the track is returned to the fp3 position. Furthermore, slow motion control playback can be done by alternately repeating still image playback and normal playback.
The speed is determined by the ratio between still image playback and normal playback. Quick motion playback is possible by forcing the sensor to the next track.

In addition, the signal recorded on the disk is read by electrically picking up the maximum rrp capacitance change between the disk, which is made of plastic mixed with fine carbon particles to make it conductive, and the electrode of the sensor. .

In areas where there are holes (bits), the capacitance value decreases,
The capacitance value increases in areas where there are no holes (bits). Note that the amount of change in capacitance value at this time is only 10-4 p.
It is about F, but about I G fiz (1000M 1
By connecting it to a circuit resonating at 150 kHz (1/10000), the resonant frequency changes by about 150 kHz (1/10000).

This change is then detected by an electronic circuit and further amplified.
A video signal and an audio signal are obtained. Additionally, a tracking signal can also be obtained at the same time.

The above is an information signal recording medium according to the present invention, and an information signal (video signal and audio signal) is recorded on the information signal track of such a recording medium (disc) by the above-described information signal recording method according to the present invention. Ru.

Note that the information signal recording medium of the present invention is limited to one in which the information signal is recorded by changing the capacitance value as described above, for example, one in which the information signal is recorded by changing the reflectance of laser light. It may also be recorded by magnetic changes.

(Effects of the Invention) As described above, according to the information signal recording method and information signal recording medium of the present invention, it is compatible with the recording method of an existing recorded recording medium and the recording medium recorded by this existing recording method. The video signal can be recorded in a wide band while maintaining the brightness, and there is no need to constantly attenuate the level of the audio frequency band of the video signal in order to widen the brightness signal as in the past.
The feature is that most video signals can be recorded as they are.

[Brief explanation of the drawing]

1 and 2 are block diagrams showing each embodiment of the information signal recording system according to the present invention, FIG. 3 is a diagram showing an example of a specific circuit of the variable attenuation circuit constituting the present invention, and FIG. figure(
a) is a diagram showing the frequency spectrum of an information signal in the V)(D format, FIG. 4(b) is a diagram showing the frequency spectrum of an information signal in the NTSC format, and FIG. 5 is a diagram showing the frequency spectrum of an information signal in the VHD format. FIG. 6 is a diagram showing the frequency spectrum of a frequency-modulated information signal recorded on a reflected light method video disk, and FIG. FIG. 8 is a diagram showing the shape of an embodiment of the information signal recording medium according to the present invention. FIG. 9 is a diagram showing the frequency characteristics of the wideband information signal to be recorded. FIG. 9 is the information signal recording medium according to the present invention. It is a diagram for explaining the state of a trace of a sensor that reads a signal recorded in an example of 1.11... Input terminal, 2... Noise attenuation filter (F), 3.14...・Low pass filter (LPF), 4...
Variable attenuation circuit, 5.6... Amplifier, 7... Band pass filter (BPF), 8... Smoothing circuit, 9... Adder, 10... Output end f, 12... Bypass Filter (HPF), 13... All band pass filter, 15, 16... Variable gain amplifier, 17... Inverting circuit, 18... Information signal recording medium, VRI, VB2...
Variable resistance. ((2> (b)
剟■? 6, 2φ old B figure 62 %9 figure

Claims (4)

[Claims] (1) In an information signal recording method in which a video signal and an audio signal are simultaneously recorded on a recording medium, the video signal and the audio signal share a frequency on the frequency spectrum of each signal. When the level (or energy component) of this frequency sharing band portion exceeds a certain level, the level (or energy component) of a predetermined frequency band portion including the frequency sharing band portion of the video signal is attenuated, and then the video signal is An information signal recording method characterized in that a signal and the audio signal are simultaneously recorded on a recording medium. (2) The information signal recording system according to claim 1, wherein the video signal is a modulated signal. (3) In an information signal recording medium on which a video signal and an audio signal are simultaneously recorded, the frequency of the video signal is shared in a band portion that shares a frequency on the frequency spectrum of each signal of the video signal and the audio signal. Band level (
or energy component) exceeds a certain level, the level (or energy component) of the video signal in a predetermined frequency band portion including the frequency sharing band portion of the video signal is attenuated and recorded. Information signal recording medium. (4) The information signal recording medium according to claim 3, wherein the video signal is a modulated signal.