JPH07298295A - Camera integrated recording / playback device - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] To obtain a camera-integrated recording / reproducing apparatus capable of reducing the number of two A / D converters used after the switch for color difference signals. The color difference signals R-Y and B-Y generated at a sampling frequency f _mk in a camera signal generation unit A are converted into 4 f _sc by frequency conversion circuits 6 and 7, and the luminance signal Y is D /
It is converted to analog by the A converter 4. On the other hand, the externally input chroma signal C is sampled at 4 f _sc by the A / D converter 13 and digitized, and then the color difference signal is demodulated by the demodulator 14 and the switches 15 to 17 together with the externally input luminance signal Y. And is switched to each signal from the camera side. The Y signal obtained from the switches 15 to 17 is digitized at 13.5 MHz by the A / D converter 18, and the RY and BY signals are converted to the frequency conversion circuit 1.
It is converted to 13.5 MHz at 9 and 20, added to the recording / reproducing unit 33 together with the signal Y, processed at 13.5 MHz, and then recorded on the magnetic tape 35.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera-integrated recording / reproducing apparatus in which a camera and a recording / reproducing apparatus such as a VTR for recording / reproducing an image taken by the camera are integrated.

[0002]

2. Description of the Related Art In recent years, digitalization of signal processing has been actively promoted in consumer video cameras.
In a camera-integrated VTR, in particular, the camera signal processing unit has been digitalized relatively early, but recently, in the recorder unit, the digital recording system is being established, and the format for recording is being set. Proposed.

Conventionally, the sampling frequency used in the camera signal processing unit is the number of pixels of the image pickup device, NTSC, PA.
It is decided depending on the television system such as L. Hereinafter, this sampling frequency will be referred to as f _mk . On the other hand, according to the currently proposed recording format, the sampling frequency of the recorder section that performs digital processing is 13.5 MHz.
Is specified in. Therefore, the digital image data generated by the camera signal processing unit cannot be directly transferred to the recorder unit. Therefore, a camera-integrated VTR shown in FIG. 2 has been proposed in which the output signal of the camera signal processing unit is once D / A converted and supplied as an analog camera signal to the recorder unit.

In FIG. 2, a subject image formed through the lens 201 is photoelectrically converted by the image sensor 202. Noise is removed from the video signal by the double correlation sampling circuit 203, and the gain is controlled by the AGC circuit 204.
The signal is converted into a digital signal by the A / D converter 205 using the sampling frequency f _mk and is applied to the digital signal processing circuit 209.

The digital signal processing circuit 205 digitally processes the video signal using the sampling frequency f _mk to generate a digital luminance signal Y and color difference signals RY and BY according to a predetermined television system.

The luminance signal Y is converted into an analog signal by the D / A converter 210, noise is removed by the low pass filter 215, and the band is limited by the low pass filter 217 via the switch 221. Further, it is converted into a digital signal by the A / D converter 206 by using the sampling frequency of 13.5 MHz, and the digital recorder unit 228.
Added to.

The color difference signals R-Y and B-Y are quadrature-modulated by a modulation circuit 226, and a D / D signal is generated as a chroma signal 235.
It is converted into an analog signal by the A converter 211. Next, noise is removed by the low-pass filter 216, and the switch 2
The color difference signal is demodulated by the demodulation circuit 225 via 22.
The demodulated color difference signals are respectively sent to the A / D converter 20.
After being converted into a digital signal by using a sampling frequency of 13.5 MHz at 7, 208, it is added to the digital recorder unit 228.

In the digital recorder section 228,
The luminance signal Y and the color difference signals RY and BY are digitally processed using a sampling frequency of 13.5 MHz,
After converting to a signal of a predetermined format, the magnetic tape 2
Record at 29.

At the time of reproduction, the signal reproduced from the magnetic tape 229 is processed by the digital recorder section 228 to demodulate the luminance signal Y and the color difference signals RY and BY. These signals are respectively sent to the D / A converters 212, 213,
It is converted into an analog signal at 214 and the low pass filter 2
After noise removal by 18, 219 and 220, the luminance signal Y is output from the output terminal 232 via the switch 223, the color difference signal is modulated by the modulation circuit 227, and the chroma signal C is output.
Is output from the output terminal 233 via the switch 224.

A luminance signal Y and a chroma signal C are input from an external signal source to the external input terminals 230 and 231.
These signals are switched and selected from the signals from the camera by the switches 221 and 222, added to the low pass filter 217 and the demodulation circuit 225, and digitally processed in the same manner as described above and recorded on the magnetic tape 225.
The signals from the camera are selectively switched by the switches 223 and 224, added to the output terminals 232 and 233, and monitored.

[0011]

In the conventional example shown in FIG. 2, the A / D conversion is performed at the sampling frequency f _mk.
Converter 205 and sampling frequency 13.5 MH
Three A / D converters 206-2 for A / D conversion with z
Therefore, there is a problem that the circuit scale becomes very large because a total of four A / D converters such as 08 are required.

The present invention has been made to solve the above problems, and an object thereof is to provide a camera-integrated recording / reproducing apparatus capable of reducing the number of A / D converters.

[0013]

According to a first aspect of the present invention, a first A / D for converting a video signal obtained from an image pickup device into a digital signal by using a first sampling frequency.
A converter, a camera signal processing circuit for digitally processing the output of the first A / D converter using the first sampling frequency, and a luminance signal and a dye signal, and a camera signal processing circuit A first frequency conversion circuit for converting the color difference signal into a color difference signal with a second sampling frequency, and a second frequency conversion circuit for converting the color difference signal with the second sampling frequency into a color difference signal with a third sampling frequency A circuit, a D / A converter for converting the brightness signal obtained from the camera signal processing circuit into an analog brightness signal, and a second for converting the analog brightness signal into a digital brightness signal using the third sampling frequency. The A / D converter, the digital luminance signal, and the color difference signal of the third sampling frequency are input to the first Digitally processed at a sampling frequency of, records the processed signal on a recording medium is provided with a recording and reproduction processing unit for processing the reproduction signal obtained by reproducing the recording medium.

According to a second aspect of the present invention, a first A / D converter for converting a video signal obtained from the image pickup device into a digital signal using a first sampling frequency,
A camera signal processing circuit that generates a luminance signal and a dye signal by digitally processing the output of the first A / D converter using the first sampling frequency;
A first frequency conversion circuit that converts the color difference signal into a color difference signal having a second sampling frequency, a D / A converter that converts the luminance signal into an analog luminance signal, and an externally input analog chroma signal into the second frequency conversion circuit. A for converting to a digital chroma signal using the sampling frequency of
/ D converter, a demodulation circuit for demodulating the color signal of the digital chroma signal using the second sampling frequency, and the second sampling frequency obtained from the demodulation circuit and the first frequency conversion circuit, respectively. A first switch for selecting one of the color difference signals, a second switch for selecting one of the analog luminance signal obtained from the D / A converter and an externally input analog luminance signal, and the second switch. A second frequency conversion circuit for converting the color difference signal of the second sampling frequency obtained from the first switch into a dye signal of the third sampling frequency; and the analog luminance signal obtained from the second switch, A second A / D converter for converting into a digital luminance signal using a sampling frequency of 3; The digital luminance signal obtained from the D converter and the color difference signal having the third sampling frequency are digitally processed at the third sampling frequency, the processed signal is recorded on a recording medium, and the reproduced signal is processed. And a recording / reproducing processing unit for performing the same.

[0015]

According to the first aspect of the invention, the color difference signal of the first sampling frequency obtained from the camera signal processing circuit is sequentially converted into the second and third sampling frequencies by the first and second frequency conversion circuits. It is then sent to the recording / playback processing unit. The luminance signal is once D / A converted, then A / D converted at the third sampling frequency, and sent to the recording / reproducing processing unit. Therefore, the recording / reproducing processing unit can perform digital processing using the third sampling frequency.

According to the invention of claim 2, the color difference signal of the first sampling frequency obtained from the camera signal processing circuit is sequentially converted into the second and third sampling frequencies by the first and second frequency conversion circuits. It is then sent to the recording / playback processing unit. In addition, the luminance signal is once D / A converted and then the third
After being A / D converted at the sampling frequency of, the data is sent to the recording / reproducing processing unit. Therefore, the recording / reproducing processing unit can perform digital processing using the third sampling frequency. When a luminance signal and a chroma signal are input from the outside, a color difference signal of the second sampling frequency is demodulated from the chroma signal, and the luminance signal and a signal from the camera are switched by a switch together with the luminance signal. The luminance signal obtained from the switch is A / D converted at the third sampling frequency, and the chrominance signal is converted to the third sampling frequency and then added to the recording / reproducing processing unit to be digitally processed.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. In FIG. 1, A is a camera signal generation unit, C is an external input unit that inputs a video signal from the outside, B is a recording / reproduction that digitally processes and records the video signal from the camera signal generation unit A and the external input unit C. A section D is an output section for outputting the signal reproduced by the recording / reproducing section B or the signal from the camera signal generating section A or the external input section C to the outside.

1 is an image pickup device such as CCD, 2 is an A / D converter, 3 is a camera signal processing circuit, 4 is a D / A converter, 5 is a low-pass filter, 6 and 7 are frequency conversion circuits,
8 is a composite video signal input terminal, 9 is an S terminal, 1
0 is a Y / C separation circuit, 11 and 12 are switches, 13 is A
A / D converter, 14 is a demodulation circuit, 15, 16, 17 are switches, 18 is an A / D converter, and 19 and 20 are frequency conversion circuits.

Reference numeral 21 is a D / A converter, 22 and 23 are frequency conversion circuits, 24 is a low-pass filter, 25 and 26,
27 is a switch, 28 is a quadrature modulation circuit, 29 is a D / A converter, 30 is a bandpass filter, 31 is a luminance signal output terminal, 32 is a chroma signal output terminal, 33 is a recording / reproducing processing unit, and 34 is a magnetic head. , 35 are magnetic tapes.

Next, the operation of the above configuration will be described.
It First, at the time of shooting, the switches 15 to 17 and 25 to 2
All of 7 are connected to the b side. Therefore, the camera
Sampling frequency f generated by the signal generation unit A _mkof
The color difference signals RY and BY are frequency conversion circuits, respectively.
Sampling frequency 4f at 6 and 7_sc(F_sc: Sub carry
A frequency) and then through switches 16 and 17
The frequency conversion circuits 19 and 20 and the switches 26 and 27.
It is input to the quadrature modulation circuit 28 via the.

The digital luminance signal Y generated by the camera signal generation unit A is analog-converted by the D / A converter 4 and then band-limited by the low-pass filter 5, and the A / D signal is supplied via the switch 15. Converter 18,
It is output to the output terminal 31 via the switch 25. At this time, the sampling frequency of the A / D converter 18 is 1
The frequency is 3.5 MHz, and the frequency conversion circuits 19 and 20 frequency-convert the digital color difference signal input at the sampling frequency 4f _sc to 13.5 MHz.

Accordingly, the luminance / color difference signal having a sampling frequency of 13.5 MHz is input to the recording / reproducing processing unit 33, subjected to predetermined processing and recorded on the magnetic tape 35 via the magnetic head 34. On the other hand, the quadrature modulation circuit 28 digitally quadrature-modulates the input color difference signal and then D / A
Converted to analog chroma signal by converter 29,
It is output from the output terminal 32 via the bandpass filter 30.

Next, at the time of reproduction, the digital luminance / color difference signal reproduced from the magnetic tape 35 by the recording / reproduction processing unit 33 has a sampling frequency of 13.5 MHz, and the luminance signal Y is analog-converted by the D / A converter 21. , The color difference signals RY and BY are input to the frequency conversion circuits 22 and 23. The switches 25 to 27 are connected to the side a during reproduction. Therefore, the D / A converter 21
The luminance signal analog-converted by the low-pass filter 2
After being band-limited at 4, it is applied to the output terminal 31 via the switch 25 and output to the outside. Further, the color difference signals are converted from the sampling frequency of 13.5 MHz to 4 f _sc by the frequency conversion circuits 22 and 23, and the switch 2
It is input to the quadrature modulation circuit 28 via 6 and 27.

On the other hand, when the luminance and chroma signals are input from the S terminal 9, the switches 11 and 12 are set to the a side.
When a composite video signal is input from the terminal 8, the switches 11 and 12 are on the b side. The composite video signal is separated into a luminance signal Y and a chroma signal C by the Y / C separation circuit 10 and input to the switches 15-17. Therefore, even if the input video signal is a composite signal, the external input video signal is output in a state of being separated into the luminance / chroma signal by the external input section C.

The luminance signal Y remains analog and the switch 15
In addition, the chroma signal C is digitally converted by the A / D converter 13 at the sampling frequency 4f _sc , and demodulated by the demodulation circuit 14 into a digital color difference signal.

When a video signal is input from the outside, the switches 15 to 17 are connected to the a side and the switches 25 to 27 are connected to the b side. Therefore, the analog luminance signal of the external input is input to the A / D converter 18, and the frequency conversion circuit 1
An externally input digital color difference signal having a sampling frequency of 4 f _sc is input to 9 and 20. In addition, the signal is transmitted to the output unit D in the same manner as when capturing an image.

In the present embodiment, the luminance / color difference signals generated by the camera signal processing circuit 3 are oversampled by 2 to perform frequency conversion, and the digital image data is passed to the recording / reproducing section 33. However, the luminance signal Y
2), the 2f _mk -13.5 HMz component is folded back to the base band component of the luminance signal, so the luminance signal is once converted into analog, and the recording / reproducing processing unit 33 side converts the sampling frequency into 13.5 HMz and digitally converts it. 2f _mk -13.5 MHz for color difference signals RY and BY
Since the component does not return to the baseband component of the color difference signal, the sampling frequency is converted to transfer the image data between the camera signal processing circuit 3 and the recording / reproducing processing unit 33. As a result, it is possible to reduce the number of A / D converters having a large circuit scale as compared with the related art.

When comparing FIG. 1 and FIG. 2, the two A / D converters 207 and 208 of FIG. 2 can be omitted. In the example of FIG. 1, when the external chroma signal C is input, the A / D converter 13 is used, but even in that case, one A / D converter can be reduced.

In FIG. 1, the A / D converter 2 is a first A / D converter, and the A / D converter 18 is a second A / D converter.
A / D converter and A / D converter 13 are the third A
/ D converter. The switches 16 and 17 are first switches, and the switch 15 is a second switch.
Further, the frequency conversion circuits 6 and 7 are a first frequency conversion circuit,
The frequency conversion circuits 19 and 20 are second frequency conversion circuits. Further, f _mk is the first sampling frequency, 4f _sc is the second sampling frequency, and 13.5 MHz is the third sampling frequency. Although the magnetic tape 35 is used as the recording medium, a semiconductor memory, a disk memory or the like may be used instead.

[0030]

As described above, according to the first aspect of the invention, the color difference signal of the first sampling frequency obtained from the camera signal processing circuit is supplied to the second and third color conversion circuits by the first and second frequency conversion circuits. The sampling frequency is sequentially converted and sent to the recording / reproducing processing unit, and the luminance signal is once D / A converted, A / D converted at the third sampling frequency, and then sent to the recording / reproducing processing unit.

Further, according to the invention of claim 2, when a luminance signal and a chroma signal are further input to the above configuration, the color difference signal of the second sampling frequency is demodulated from the chroma signal, and the luminance signal and the chroma signal are switched together with the luminance signal. Select to switch from the signal from the camera with A, D / D convert the selected luminance signal at the third sampling frequency, and convert the color difference signal to the third sampling frequency, and then send it to the recording / reproducing processing unit. Configured.

Therefore, according to the present invention, it is possible to eliminate the two A / D converters used for adding the color difference signal to the digital recording / reproducing processing unit, which is conventionally used, and the circuit scale can be reduced and the cost can be reduced. There is an effect that can be realized.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a block diagram showing a conventional camera-integrated VTR.

[Explanation of symbols]

 1 image sensor 2 A / D converter 3 camera signal processing circuit 4 D / A converter 6, 7 frequency conversion circuit C external input section 13 A / D converter 14 demodulation circuit 15, 16, 17 switch 18 A / D converter 19, 20 Frequency conversion circuit 33 Recording / reproduction processing unit 35 Magnetic tape

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location H04N 11/04 D 9185-5C

Claims (2)

[Claims] 1. A first A / D converter for converting a video signal obtained from an image pickup device into a digital video signal using a first sampling frequency, and a digital video signal obtained from the first A / D converter. And a camera signal processing circuit for digitally processing the image signal using the first sampling frequency to generate a luminance signal and a color difference signal, and a color difference signal having a second sampling frequency from the color difference signal obtained from the camera signal processing circuit. A first frequency conversion circuit for converting the color difference signal having the second sampling frequency obtained from the first frequency conversion circuit into a color difference signal having a third sampling frequency, A D / A converter for converting the luminance signal obtained from the camera signal processing circuit into an analog luminance signal; A second A / D converter for converting the analog luminance signal obtained from the A converter into a digital luminance signal using the third sampling frequency; and the digital luminance signal obtained from the second A / D converter. A color difference signal of the third sampling frequency obtained from the second frequency conversion circuit is digitally processed at the third sampling frequency, the processed signal is recorded on a recording medium, and the reproduced signal is reproduced from the recording medium. A camera-integrated recording / reproducing apparatus including a recording / reproducing processing unit for processing the. 2. A first A / D converter for converting a video signal obtained from an image sensor into a digital video signal using a first sampling frequency, and a digital video signal obtained from the first A / D converter. And a camera signal processing circuit for digitally processing the image signal using the first sampling frequency to generate a luminance signal and a color difference signal, and a color difference signal having a second sampling frequency from the color difference signal obtained from the camera signal processing circuit. To a first frequency conversion circuit, a D / A converter that converts the luminance signal obtained from the camera signal processing circuit into an analog luminance signal, and an externally input analog chroma signal to the second sampling frequency. A third A / D converter for converting to a digital chroma signal by using the third A / D converter A demodulation circuit for demodulating a color difference signal from the digital chroma signal obtained from the above using the second sampling frequency, and a color difference signal having the second sampling frequency obtained from the demodulation circuit and the first frequency conversion circuit, respectively. A first switch for selecting one of the analog luminance signal obtained from the D / A converter and an externally input analog luminance signal, and a first switch for selecting one of A second frequency conversion circuit for converting the color difference signal of the second sampling frequency obtained from the switch into a color difference signal of the third sampling frequency; and the analog luminance signal obtained from the second switch to the third luminance conversion circuit. A second A / D converter for converting into a digital luminance signal using a sampling frequency; The digital luminance signal obtained from the D / D converter and the color difference signal having the third sampling frequency obtained from the second frequency conversion circuit are digitally processed at the third sampling frequency, and the processed signal is a recording medium. A camera-integrated recording / reproducing apparatus having a recording / reproducing processing unit for processing a reproduced signal recorded on the recording medium and reproducing the recording medium.