JPH0564132A - Still picture recording and reproducing device - Google Patents

Abstract

PURPOSE:To prevent deterioration in picture quality at recording and reproduction by using a track of an Hi-Fi audio signal of a video tape recorder and recording a video signal thereon without converting a digital signal. CONSTITUTION:Clamp circuits 12, 13 give a video signal to A/D converter circuits 15, 16 at recording of an inputted analog still video signal and the signal is converted into a digital video signal, given to a modulation circuit 20, in which the signal is modulated into a signal on an Hi-Fi audio track and recorded on a recording medium by audio rotary heads 33, 34. On the other hand, the Hi-Fi signal reproduced by the heads 33, 34 is converted into the digital video signal at a demodulation circuit 21, given to D/A converter circuits 23, 24, in which the signal is converted into an analog video signal and outputted to a video processing circuit 25. Thus, the digital still picture video signal is recorded on the Hi-Fi audio track in this way to implement recording and reproduction of the digital still picture signal without deterioration in the picture quality.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing apparatus for still image video signals.

[0002]

2. Description of the Related Art An example of a conventional still image recording / reproducing apparatus is shown in FIG.
Shown in.

In the figure, outputs of a Y / C separation circuit 11 for separating an input composite video signal into a luminance signal Y and a chroma signal C are clamp circuits 12 and 13 provided corresponding to the respective outputs. It is led to each data input of the memory circuit 17 via the A / D conversion circuits 15 and 16.

Further, each data output of the memory circuit 17 is
D / A conversion circuits 23 and 2 provided corresponding to each
4 is led to the video processing circuit 25, and the output of the video processing circuit 25 is supplied to each of the video rotary heads 31 via the fixed terminals a and a of one of the changeover switches S5 and S6 and the movable terminals c and c. , 32. The other fixed terminals b, b of the changeover switches S5, S6 are connected to a video reproduction circuit system (not shown).

On the other hand, the luminance signal Y separated by the Y / C separation circuit 11 is also led to the sync separation circuit 14,
The output of the sync separation circuit 14 is the memory control circuit 1
It is led to 8.

The memory control circuit 18 gives a control signal based on the horizontal synchronizing signal H _S and the vertical synchronizing signal V _S given from the sync separating circuit 14 to the memory circuit 17, and also gives a synchronizing timing signal to the synchronizing generating circuit 2.
6, the output of the synchronization generating circuit 26 is guided to the video processing circuit 25 as a horizontal synchronizing signal H _S and a vertical synchronizing signal V _{S which} are timed.

Next, the operation of the still image recording / reproducing apparatus having the above configuration will be described.

At the time of recording, when a capture instruction is given by an external switch (not shown) or the like, the Y / C separation circuit 11 converts the input decoded video signal into a luminance signal Y and a chroma signal C.
The separated luminance signal Y is supplied to the clamp circuit 13 and the sync separation circuit 14, and the separated chroma signal C is supplied to the clamp circuit 12.

The clamp circuit 12 clamps the chroma signal C and then supplies it to the A / D conversion circuit 15, where it is converted into a digital chroma signal and supplied to the memory circuit 17. Also,
The clamp circuit 13 clamps the luminance signal Y and then A /
The signal is supplied to the D conversion circuit 16, where it is converted into a digital luminance signal and supplied to the memory circuit 17.

On the other hand, the sync separation circuit 14 separates the horizontal sync signal H _S and the vertical sync signal V _S from the luminance signal Y and supplies them to the memory control circuit 18. The memory control circuit 18 gives a control signal based on the horizontal synchronizing signal H _S and the vertical synchronizing signal V _S to the memory circuit 17.

In the memory circuit 17, each A / D conversion circuit 1
The digital chroma signal and the digital luminance signal given from 5, 16 are stored for one field under the control of the memory control circuit 18, and the stored digital chroma signal and digital luminance signal for one field are stored in the memory control circuit 18. It is given to each of the following D / A conversion circuits 23 and 24 under the control of. The memory control circuit 18 performs control to repeatedly output the data captured in the memory circuit 17 unless a new static image is instructed by an operation of an external switch (not shown) or the like.

The D / A conversion circuits 23 and 24 respectively convert the digital chroma signals and the digital luminance signals supplied from the memory circuit 17 into analog signals, and output them to the video processing circuit 25 as output chroma signals and output luminance signals. give.

On the other hand, the sync generation circuit 26 generates a horizontal sync signal H _S and a vertical sync signal V _S in accordance with the sync timing signal supplied from the memory control circuit 18,
Since the video signal is output to the video processing circuit 25, the video processing circuit 25 outputs the output chroma signal and the output luminance signal from the D / A conversion circuits 23 and 24 and the synchronization generation circuit 26.
From the horizontal synchronizing signal H _S and the vertical synchronizing signal V _S
A decoded video signal is created by and each changeover switch S
5, fixed terminals a and a of S6 are given.

Since the changeover switches S5 and S6 connect the movable terminals c and c to the fixed terminals a and a during recording, the video rotary heads 31 are recorded on the recording tracks of the recording medium (not shown). , 32, the decoded video signals, which are still image video signals, are sequentially recorded on predetermined recording tracks.

During reproduction, each changeover switch S5,
The fixed terminals b, b of S6 are movable terminals c, c during reproduction.
Since the fixed terminals b and b are connected to each other, the decoded video signals recorded on the recording tracks of the recording medium (not shown) are sequentially reproduced from the predetermined recording tracks by the video rotary heads 31 and 32, respectively. Not output to the video reproduction circuit system, and the still image video is reproduced.

[0016]

As described above, in the conventional still image recording / reproducing apparatus, the input analog decoded video signal is once converted into a digital signal and then a still image video signal is created. Since the signal is converted back to the analog signal and recorded on the recording medium, there is a problem that the original image quality cannot be obtained due to signal deterioration during recording and reproduction.

The present invention has been made in view of the above circumstances, and an object thereof is to convert an analog still image video signal into a digital signal and record the digital signal in a Hi-Fi audio area, thereby recording and reproducing. It is an object of the present invention to provide a still image recording / reproducing device that prevents deterioration of image quality.

[0018]

In order to solve the above-mentioned problems, a still picture recording / generating apparatus of the present invention is a still picture recording / recording apparatus in a Hi-Fi video tape recorder, at the time of recording an inputted analog still picture image signal. A conversion means for converting the video signal into a digital video signal, a modulation means for modulating the digital video signal converted by the conversion means into a signal in the Hi-Fi audio area of the video tape recorder, and the modulation means. A reproducing means for recording the Hi-Fi signal in a predetermined area of the recording medium, and reproducing the Hi-Fi signal recorded in the recording medium when reproducing the Hi-Fi signal recorded in the recording medium. Means, demodulating means for demodulating the Hi-Fi signal reproduced by the reproducing means into an original digital video signal, and demodulating means demodulated by the demodulating means. A configuration that includes a conversion means for outputting a barrel video signal for subsequent video signal processing system is converted into an analog still image signal.

[0019]

When the input analog still picture image signal is recorded, the converting means converts the still picture image signal into a digital picture signal, and then the modulating means converts the digital picture signal into the Hi-Fi audio area of the video tape recorder. The signal is modulated into a signal, and the modulated Hi-Fi
The signal is recorded in a predetermined area of the recording medium.

Further, at the time of reproducing the Hi-Fi signal recorded on the recording medium, the H recorded on the recording medium by the reproducing means.
After the i-Fi signal is reproduced, the demodulation means outputs Hi.
-The Fi signal is demodulated to the original digital video signal, the digital video signal demodulated by the conversion means is converted into an analog still picture video signal, and the analog still picture video signal is output to the subsequent video signal processing system.

That is, the digital still image video signal is Hi
Since the recording is performed in the -Fi audio area, the recording and reproduction of the analog still image signal is not affected, and the deterioration of the image quality due to the recording and reproduction can be prevented.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the electrical construction of a still image recording / reproducing apparatus of the present invention. However, in the figure, the same blocks as those of the conventional apparatus shown in FIG. 3 are denoted by the same reference numerals.

That is, a Y / C separation circuit 1 for separating the input composite video signal into a luminance signal Y and a chroma signal C.
Each output of 1 passes through the clamp circuits 12 and 13 and the A / D conversion circuits 15 and 16 which are provided correspondingly,
The changeover switches S1 and S2 are connected to one fixed terminals a and a of the changeover switches S1 and S2, and the movable terminals c and c of the changeover switches S1 and S2 are led to the respective data inputs of the memory circuit 17.

Each data output of the memory circuit 17 is
Changeover switches S3, S4 provided corresponding to each
Of the changeover switch S
One fixed terminal a, a of S3, S4 is connected to one fixed terminal a, a of each changeover switch S5, S6 via each D / A conversion circuit 23, 24 provided corresponding to each. Has been done. The movable terminals c and c of the changeover switches S5 and S6 are led to the voice rotary heads 33 and 34, respectively.

The other fixed terminals b, b of the changeover switches S5, S6 are connected to the fixed terminals a, b of the changeover switch S7, and the movable terminal c of the changeover switch S7 is a demodulation circuit. 21. Further, the pulse generation circuit 22 is connected to the switching control input of the changeover switch S7.
The output of is derived. The pulse generation circuit 22 is a block that outputs a pulse (head switching pulse) for switching the signals reproduced from the two audio rotary heads 33 and 34 for each field during reproduction.

The respective outputs of the demodulation circuit 21 are connected to the other fixed terminals b, b of the changeover switches S3, S4. Further, the other fixed terminals b, b of the respective changeover switches S1, S2 are led to the video processing circuit 25 via the D / A conversion circuits 23, 24 provided correspondingly to the video processing circuit 25, respectively. The output of 25 is output to a subsequent signal processing circuit (not shown) as a decoded video signal.

On the other hand, the luminance signal Y separated by the Y / C separation circuit 11 is also led to the sync separation circuit 14,
The output of the sync separation circuit 14 is the memory control circuit 1
It is led to 8.

The memory control circuit 18 gives a control signal based on the horizontal synchronizing signal H _S and the vertical synchronizing signal V _S given from the sync separating circuit 14 to the memory circuit 17, and also gives a synchronizing timing signal to the synchronizing generating circuit 2.
6, the output of the synchronization generation circuit 26 is guided to the video processing circuit 25 as a horizontal synchronization signal H _S and a vertical synchronization signal V _{S which} are timed. Further, the memory control circuit 18 uses the changeover switches S1, S2, S.
A switching control signal for switching the connection between recording and reproduction is output to the switching control input of 3, S4, S5, S6. Further, the memory control circuit 18 is instructed to record and reproduce by operating an external switch (not shown) or the like, and is also instructed to capture a new still image.

Next, the operation of the still image recording / reproducing apparatus having the above configuration will be described.

At the time of recording, each of the changeover switches S1 to S6 changes over the connection of the movable terminal c to the fixed terminal a side according to each changeover control signal from the memory control circuit 18.

In this state, when a capture instruction is given by an external switch (not shown) or the like, the Y / C separation circuit 11 separates the input decoded video signal into a luminance signal Y and a chroma signal C, and the separated luminance signal. Y is supplied to the clamp circuit 13 and the sync separation circuit 14, and the separated chroma signal C is supplied to the clamp circuit 12.

The clamp circuit 12 clamps the chroma signal C and then supplies the chroma signal C to the A / D conversion circuit 15, which converts it into a digital chroma signal and then supplies it to the memory circuit 17 via the changeover switch S1. Further, the clamp circuit 13 clamps the luminance signal Y and then supplies it to the A / D conversion circuit 16,
Here, after conversion into a digital luminance signal, the changeover switch S
2 to the memory circuit 17.

On the other hand, the sync separation circuit 14 separates the horizontal sync signal H _S and the vertical sync signal V _S from the luminance signal Y and supplies them to the memory control circuit 18. The memory control circuit 18 gives a control signal based on the horizontal synchronizing signal H _S and the vertical synchronizing signal V _S to the memory circuit 17.

In the memory circuit 17, each A / D conversion circuit 1
The digital chroma signal and the digital luminance signal given from 5, 16 are stored for one field under the control of the memory control circuit 18, and the stored digital chroma signal and digital luminance signal for one field are stored in the memory control circuit 18. In accordance with the control from 1), it is given to the modulation circuit 20 via each of the changeover switches S3, S4. The memory control circuit 18 performs control to repeatedly output the data captured in the memory circuit 17 unless a new static image is instructed by an operation of an external switch (not shown) or the like.

The modulation circuit 20 converts the digital signal into a predetermined frequency signal according to the table shown in FIG.

That is, a combination of the digital luminance signal Y and the digital chroma signal C outputs signals of four kinds of frequencies. That is, when the digital luminance signal Y is "0" level and the digital chroma signal C is "0" level, a frequency signal of 1.24 MHz, the digital luminance signal Y is "0" level, and the digital chroma signal C is "1" level. When the digital luminance signal Y is "1" level, the digital luminance signal Y is "1" level, the digital luminance signal Y is "1" level, the digital luminance signal Y is "1" level, When the chroma signal C is at "1" level, a frequency signal of 1.36 MHz is output.

Further, as shown in FIG. 3, the modulation circuit 20 modulates the digital signal by outputting each frequency signal converted according to the table of FIG. 2 for one cycle. Since all of these frequencies are within the recording frequency band determined for the Hi-Fi audio signal of the video tape recorder,
It can be recorded on the recording medium by the voice rotary heads 33 and 34.

On the other hand, at the time of reproduction, each changeover switch S1.
In S6, the connection of the movable terminal c is switched to the fixed terminal b side by each switching control signal from the memory control circuit 18. Further, the changeover switch S7 is sequentially changed over and controlled by the head switching pulse generated by the pulse generating circuit 22.

In this state, the voice rotary head 33,
Each frequency signal reproduced by 34 is given to the demodulation circuit 21, demodulated to the original digital chroma signal and digital luminance signal by the procedure reverse to the above, and given to the memory circuit 17 via each changeover switch S3, S4. Be done. The memory circuit 17 stores the digital chroma signal and the digital luminance signal supplied from the demodulation circuit 21 for one field under the control of the memory control circuit 18, and stores the stored digital chroma signal and digital luminance signal for one field. , The changeover switches S1 and S2 under the control of the memory control circuit 18.
Is given to each D / A conversion circuit 23, 24 via.

In each of the D / A conversion circuits 23 and 24, the digital chroma signal and the digital luminance signal for one field given via the changeover switches S1 and S2 are converted into analog signals, respectively, and the output chroma signal and the output are outputted. It is given to the video processing circuit 25 as a luminance signal.

On the other hand, the synchronization generating circuit 26 generates the horizontal synchronizing signal H _S and the vertical synchronizing signal V _S according to the synchronizing timing signal given from the memory control circuit 18,
Since the video signal is output to the video processing circuit 25, the video processing circuit 25 outputs the output chroma signal and the output luminance signal from the D / A conversion circuits 23 and 24 and the synchronization generation circuit 26.
From the horizontal synchronizing signal H _S and the vertical synchronizing signal V _S
A decoded video signal is created by and and output to the subsequent signal processing circuit.

As a result, it is possible to record and reproduce the still image video signal without deterioration of the image.

In the above embodiment, the case of the VHS type video tape recorder has been described. However, by changing the output frequency of the modulation circuit 20, superimposing it on the video signal at the time of recording, etc. The still image recording / reproducing apparatus of the present invention can be applied to a video tape recorder.

[0045]

The still picture recording / reproducing apparatus of the present invention is configured to record a digital signal as it is by using the Hi-Fi audio signal area of the video tape recorder in recording / reproducing a digital still picture signal. Thus, it is possible to record and reproduce a digital still image signal without deterioration of image quality.

[Brief description of drawings]

FIG. 1 is a block diagram showing an electrical configuration of a still image recording / reproducing apparatus of the present invention.

FIG. 2 is a table showing an example of modulation in a modulation circuit.

FIG. 3 is a waveform diagram showing an example of modulation in a modulation circuit.

FIG. 4 is a block diagram showing an electrical configuration of a conventional still image recording / reproducing device.

[Explanation of symbols]

 15 A / D conversion circuit 16 A / D conversion circuit 17 Memory circuit 20 Modulation circuit 21 Demodulation circuit 23 D / A conversion circuit 24 D / A conversion circuit

Claims (1)

[Claims] 1. A Hi-Fi video tape recorder, wherein at the time of recording an input analog still image video signal, a converting means for converting the still image video signal into a digital video signal, and a digital signal converted by this converting means. A recording means for modulating the video signal into a signal in the Hi-Fi audio area of the video tape recorder; and a recording means for recording the Hi-Fi signal modulated by the modulating means in a predetermined area of the recording medium. When reproducing the Hi-Fi signal recorded on the recording medium, reproduction means for reproducing the Hi-Fi signal recorded on the recording medium, and Hi-F reproduced by the reproduction means
demodulation means for demodulating the i signal into the original digital video signal,
A still picture recording / reproducing apparatus, comprising: a converting means for converting the digital video signal demodulated by the demodulating means into an analog still picture video signal and outputting the analog still picture video signal to a subsequent video signal processing system.