JPH01125091A - Color television signal processing device - Google Patents

Abstract

PURPOSE:To obtain, even when a Y-signal and a C-signal are supplied separately, a reproduced image based on the supplied Y-signal and C-signal by providing a signal switching means between an external input terminal part and a luminance signal circuit and a color signal circuit. CONSTITUTION:In case a composite video signal is supplied to an input terminal 21, a relay 29 is set in a non-operating status, the composite video signal inputted to the input terminal 21 is amplified by a buffer amplifier 23 then supplied to the luminance signal circuit 25 and at the same time to the color signal circuit 26 through a switching glossa S1. In case a Y-signal is supplied to the input terminal 21 while a C-signal is to that 22, a detection signal from a detection circuit 32 is made obtained by the C-signal from the amplifier 24. Accordingly, a drive circuit 33 is operated, and the relay 29 also is operated. It follows that the Y-signal supplied to the terminal 21 is amplified by the buffer amplifier 23 then supplied to the luminance signal circuit 25, while the C-signal supplied to the input terminal 22 is amplified by the amplifier 24 then supplied to the color signal circuit 26 via the switching glossa S1.

Description

[Detailed description of the invention] The present invention will be explained in the following order.

A. Industrial field of application B. Outline of the invention C. Prior art D. Problem to be solved by the invention E. Means for solving the problem F. Effect G. Example H. Effect of the invention A. Industrial field of application. The present invention relates to a color television signal processing device that allows a reproduced image to be obtained based on a luminance signal and a color signal that constitute a color video signal.

B. Summary of the Invention The present invention comprises a luminance signal circuit 9 a color signal circuit 1 an image display processing section, etc., in order to be able to obtain a reproduced image based on a luminance signal and a color signal constituting a color video signal. A color television signal processing device comprising: an external input terminal section to which a composite video signal formed by combining a luminance signal and a chrominance signal, or a luminance signal and a chrominance signal separated from each other; It is arranged between the external input terminal section and each of the luminance signal circuit and the color signal circuit, so that the composite video signal from the external input terminal section or the luminance signal forming it is supplied to the luminance signal circuit, and the external input terminal section is connected to the luminance signal circuit. A first state in which the composite video signal from the terminal section or a color signal forming it is supplied to the color signal circuit, and a luminance signal and a color signal separated from each other from the external input terminal section are supplied to the luminance signal circuit and the color signal forming the composite video signal from the terminal section. signal switching means capable of selectively changing the second state supplied to each color signal circuit, the signal switching means determining whether the signal supplied to the external input terminal section is a composite video signal; Since the switching control unit determines whether the luminance signal and color signal are separated from each other and the first state or the second state is assumed depending on the result of the determination, manufacturing costs can be significantly reduced. When a composite video signal is supplied through an external input terminal section, and when mutually separated luminance signals and chrominance signals are supplied through an external input terminal section, without inconveniences such as increase in In either case, a reproduced image is obtained based on the supplied luminance signal and chrominance signal forming a composite video signal, or the luminance signal and chrominance signal supplied separately from each other.

C. Prior Art Generally, recording and reproducing of color video signals is performed using a magnetic recording and reproducing device.Recording and reproducing of such color video signals will be explained with reference to FIG.

FIG. 2 shows the configuration of the magnetic recording and reproducing device.
This magnetic recording and reproducing device consists of a recording system (1) and a reproducing system (1 [
). The recording system (1) includes an input terminal 1 to which a composite video signal is supplied as a color video signal, a low pass filter (LPF) 2. Bandpass filter (BPF)
)3. Pre-emphasis circuit 49 Frequency modulation circuit 5. Amplifier 62 frequency conversion circuit 7. The reproducing system (II) includes an amplifier 8 and a recording head 9, and the reproducing system (II) includes a reproducing head 11. Amplifier 12. Bypass filter (HPF)
13. Low-pass filter 149 frequency demodulation circuit 15. De-emphasis circuit 161 Frequency conversion circuit 17. It is configured to include an amplifier 18 and an output terminal 19, and an oscillator (O3C) 10 is provided in common to the recording system (I) and the reproduction system (II). The recording and reproduction of the color video signal is performed using the magnetic tape 20.

Based on this configuration, a luminance signal (Yfg signal) and a color signal (C signal) are separated from a composite video signal supplied to the input terminal 1 by a low-pass filter 2 and a band-pass filter 3. The Y signal separated by the low-pass filter 2 is subjected to pre-emphasis processing for frequency modulation by a pre-emphasis circuit 4, and then frequency-modulated by a predetermined carrier signal in a frequency modulation circuit 5 to obtain a pre-determined frequency band. The frequency modulated Y signal obtained from the frequency modulation circuit 5 is supplied to the amplifier 6.

On the other hand, the C signal separated by the band six filter 3 is a signal having a carrier frequency of 3.58 MHz, and is sent to the frequency conversion circuit 7 to which the 4.27 MHz oscillation output signal from the oscillator 10 is supplied. Low frequency conversion C that is converted to a low frequency band and makes the carrier frequency 688KHz
Low-frequency conversion C obtained from the frequency conversion circuit 7 as a signal
A signal is provided to an amplifier 8. Then, frequency table 11Y signal and low frequency conversion C obtained from amplifiers 6 and 8, respectively.
The signals are mixed and recorded on the magnetic tape 20 by the recording head 9.
recorded in

In addition, a signal read from the magnetic tape 20 by the RAD 11 for reproduction passes through the amplifier 12 and is then supplied to the bypass filter 13 and the low-pass filter 14. The bypass filter 13 extracts the frequency modulated Y signal, and the low-pass filter 14 A low frequency converted C signal is extracted.

The frequency-modified WY signal from the bypass filter 13 is demodulated in a frequency demodulation circuit 15, and de-emphasis processing is applied to the demodulated output by a de-emphasis circuit 16 to reproduce the original Y signal. On the other hand, the low-pass converted C signal from the low-pass filter 14 is frequency-converted in the frequency conversion circuit 17 to which the 4.27 MHz oscillation output signal from the oscillator 10 is supplied, thereby setting the carrier frequency to 3.58 MHz. The original C signal is regenerated. The reproduced Y signal and C signal are mixed and then passed through an amplifier 18 and outputted to an output terminal 19 as a composite video signal.

In this way, the composite video signal reproduced by the magnetic recording and reproducing device is supplied to a color television receiver for image reproduction based on the composite video signal, and in the color television receiver, the cathode ray tube ( CRT)
Above, do as you would for a normal received color video signal,
An image based on the composite video signal reproduced by the magnetic recording and reproducing device is obtained.

Furthermore, when recording and reproducing color video signals using the magnetic recording/reproducing device, as indicated by the broken line in FIG. It has also been proposed that the signals be derived without being mixed and used for image reproduction based on them.

D Problems to be Solved by the Invention As mentioned above, when the reproduced Y signal and C signal are used for image reproduction in a state where they are separated from each other, the reproduced Y signal and C signal However, image reproduction based on such mutually separated Y and C signals is However, there is an inconvenience in that it cannot be performed with conventional color television receivers.

In view of the above, the present invention provides a case where a composite video signal formed by combining a Y signal and a C signal is supplied, and
To make it possible to obtain a reproduced image based on the supplied Y signal and C signal even when the Y signal and C signal are supplied separately from each other, and to have a relatively simple configuration for the function. It is an object of the present invention to provide a color television signal processing device that can achieve the following.

E. Means for Solving the Problems In order to achieve the above-mentioned object, the color television signal processing device according to the present invention generates a composite video signal formed by combining -Y signal and C signal, or mutually. An external input terminal section to which separated Y and C signals are supplied, a luminance signal circuit that performs signal processing on the Y signal, a chrominance signal circuit that performs signal processing on the C signal, an external input terminal section, and the luminance signal. a signal switching means provided between each of the circuit and the color signal circuit; a switching control section controlling the signal switching means;
and an image display processing section to which respective outputs of the luminance signal circuit and the color signal circuit are supplied; a first state in which the composite video signal or the C signal forming the composite video signal, which is supplied to the signal circuit and also supplied to the external input terminal section, is supplied to the color signal circuit;
A second state in which the Y signal and the C signal supplied to the external input terminal section are supplied to the luminance signal circuit and the color signal circuit, respectively, can be selectively taken, and the switching control section is configured to control the external input terminal section. determines whether the signal supplied to the section is a composite video signal or a luminance signal and a color signal separated from each other, and sets the signal switching means to a first state or a second state according to the determination result. It is made to be taken and constituted.

1 Effect The color television signal processing device according to the present invention configured as described above has the following effects based on a relatively simple configuration.
Therefore, when a composite video signal is supplied to the external input terminal section without causing inconveniences such as a significant increase in manufacturing costs, and when mutually separated Y signals are supplied to the external input terminal section, and C signals are supplied, either the Y signal and the C signal forming the supplied composite video signal, or the Y signal and the C signal supplied separately from each other.
A reproduced image is obtained based on the signal and the C signal, and thus, for example, not only image reproduction based on a composite video signal derived from the magnetic recording and reproducing device, but also derived from the magnetic recording and reproducing device in a mutually separated state. Image reproduction is performed based on the Y signal and C signal, and it is possible to obtain a high-quality reproduced image based on the Y signal and C signal reproduced by the magnetic recording and reproducing device.

G Example Examples of the present invention will be described below.

FIG. 1 shows essential parts of an example of a color television signal processing device according to the present invention. In this example, input terminal 21
and 22 are provided, and these input terminals 21 and 2
2 is open to the outside and forms an external input terminal section. A composite video signal or a Y signal is input to the input terminal 21.
A signal is supplied to the input terminal 22, and a C signal is also supplied to the input terminal 22.

The input terminal 21 is connected via a buffer amplifier 23 to a luminance signal circuit 25 that processes the Y signal, and also connected to the buffer amplifier 23 . Contact a and switching contact S1
are selectively connected to a color signal circuit 26 for processing the C signal, while the input terminal 22 is connected to a buffer amplifier 24 . It is selectively connected to the color signal circuit 26 via the contact b1 and the switching contact St. The output terminals of the luminance signal circuit 25 and the color signal circuit 26 are connected to a matrix circuit 27, and the matrix circuit 27 further includes a red CRT 28.
R, green CRT 28G and blue CRT 28B are connected. The matrix circuit 27 receives the respective output signals of the luminance signal circuit 25 and the color signal circuit 26, forms a red drive signal, a green drive signal, and a blue drive signal, and sends them to the red CRT 28R, green CRT 28G, and blue CRT 28B, respectively. supply Further, in connection with the brightness signal circuit 25, contacts a and b= and a switching contact S are provided, and a trap 31 for removing the C signal component connects the contact a2 and the switching contact St. It is selectively connected to the luminance signal circuit 25 via the luminance signal circuit 25. The switching contacts Sl and S8 are
They are designed to be interlocked and controlled by a relay 29.

Furthermore, the presence or absence of the output of the buffer amplifier 24 is detected by the detection circuit 3.
2 and a detection output is obtained from the detection circuit 32, the drive circuit 33 connected to the detection circuit 32
is activated. The output end of the drive circuit 33 is connected to one end of the relay 29, and when the drive circuit 33 is activated, the relay 29 is activated. Therefore, the relay 29 is activated only when there is an output from the buffer amplifier 24, and the activated state and non-activated state of the relay 29 are automatically set.

Based on this configuration, when a composite video signal is supplied to the external input terminal section, that is, when a composite video signal is supplied to the input terminal 21, and when a mutually separated Y signal is supplied to the external input terminal section. and C signal are supplied, that is, input terminal 2
The following operations are performed in each case where a Y signal is supplied to input terminal 1 and a C signal is supplied to input terminal 22.

i) When a composite video signal is supplied to the input terminal 21, no output is obtained from the buffer amplifier 24, so no detection output is obtained from the detection circuit 32. Therefore, drive circuit 3
3 is not activated, and as a result, the relay 29 is kept in a non-activated state, and the switching contact S is connected to the contact a, and the switching contact St is maintained connected to the contact a2. be done. Therefore, the composite video signal supplied to the input terminal 21 is amplified by the buffer amplifier 23, and then supplied to the luminance signal circuit 25, as well as to the color signal circuit 26 through the switching contact St. As a result, a red drive signal, a green drive signal, and a blue drive signal based on the composite video signal supplied to the input terminal 21 are obtained from the matrix circuit 27, and are supplied to the red CRT 28R, green CRT 28G, and blue CRT 28B, respectively. Red CRT28R.

Color image formation is performed using the green CRT 28G and the blue CRT 28B.

Further, at this time, the C signal component in the composite video signal supplied to the luminance signal circuit 25 is removed by the trap 31 connected to the luminance signal circuit 25 through the switching contact St.

ii) When the Y signal is supplied to the input terminal 21 and the C signal is supplied to the input terminal 22, the buffer amplifier 24
A C signal is obtained as an output from , and a detection output is obtained from the detection circuit 32 in response. Therefore, the drive circuit 33
is activated, whereby the relay 29 is activated, the switching contact SI is reversed and connected to the contact bI, and the switching contact S: is reversed and connected to the contact b2. Be taken. Therefore, after the Y signal supplied to the input terminal 21 is amplified by the buffer amplifier 23,
The C signal supplied to the luminance signal circuit 25 and input terminal 22 is amplified by the bass amplifier 24 and then supplied to the chrominance signal circuit 26 through the switching contact SI. As a result, from the matrix circuit 27, the input terminal 21
A red drive signal, a green drive signal, and a blue drive signal based on the Y signal supplied to the input terminal 28 and the C signal supplied to the input terminal 22 are obtained, and the red drive signal, the green drive signal, and the blue drive signal are obtained, respectively.
Supplied to green CRT28G and blue CRT28B, red CRT28R, green CRT28G and blue CRT28
Color image formation using B is performed.

In addition, in such a case, the trap 31 is connected to the luminance signal circuit 25.
be separated from

In this way, both when a composite video signal is supplied to the external input terminal section and when mutually separated Y and C signals are supplied to the external input terminal section,
Y signal and C signal forming the supplied composite video signal;
Alternatively, a reproduced image is obtained based on the Y signal and C signal that are supplied separately from each other.

In addition, the settings of the switching contacts SI and S2 are reversed from the above,
It is also possible that the relay 29 is activated and the switching contacts St and St are reversed only when no detection output is obtained from the detection circuit 32.

Further, in the above example, when a composite video signal is supplied to the input terminal 21, the composite video signal passes through the buffer amplifier 23, then the luminance signal circuit 25 and the color signal circuit 26.
However, input terminal 2
For example, when a Y signal/C signal separation circuit such as a comb filter is connected to 1, and a composite video signal is supplied to the input terminal 21, the composite video signal is separated into a Y signal and a C signal by the Y signal/C signal separation circuit. The Y signal and C signal obtained from the Y signal/C signal separation circuit may be supplied to the luminance signal circuit 25 and the color signal circuit 26, respectively.

Effects of the Invention H As is clear from the above explanation, the color television signal processing device according to the present invention uses an external input to which a composite video signal or a Y signal and a C signal separated from each other are supplied. A terminal section is provided between the external input terminal section and the luminance signal circuit and the color signal circuit, for forming a composite video signal from the external input terminal section when the composite video signal is supplied to the external input terminal section. The Y signal is processed in the luminance signal circuit, and the C signal forming the composite video signal from the external input terminal section is processed in the color signal circuit, so that the Y signal and C signal separated from each other are processed. Signal switching means controlled by the switching control section so that when supplied to the external input terminal section, the Y signal and C signal from the external input terminal section are processed in the luminance signal circuit and the color signal circuit, respectively. Since the composite video signal is supplied to the external input terminal section, or when the Y signal and C signal are supplied to the external input terminal section separately, It is possible to obtain a reproduced image based on the Y signal and C signal supplied as forming the Y signal and the C signal, or the Y signal and C signal supplied separately from each other. Therefore, this can be achieved without inconveniences such as a significant increase in manufacturing costs.

When the color television signal processing device according to the present invention is used, for example, not only image reproduction based on a composite video signal derived from a magnetic recording and reproducing device, but also
Image reproduction based on the Y signal and C signal derived from the magnetic recording and reproducing device in a state separated from each other is possible, and high quality reproduction is possible based on the Y signal and C signal reproduced by the magnetic recording and reproducing device. This will allow you to obtain images.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing essential parts of an example of a color television signal processing apparatus according to the present invention, and FIG. 2 is a block diagram used to explain recording and reproduction of a color video signal. In the figure, 21 and 2'2 are input terminals, 25 is a luminance signal circuit, 26 is a color signal circuit, 27 is a matrix circuit, and 28R
is red CRT, 28G is green CRT, 28B is blue CR
T, 29 is a relay, 32 is a detection circuit, 33 is a drive circuit,
Sl and S2 are switching contacts.

Claims (1)

[Claims] An external input terminal section to which a composite video signal formed by combining a luminance signal and a chrominance signal or a luminance signal and a chrominance signal separated from each other is supplied, and signal processing for the luminance signal. a luminance signal circuit that performs signal processing on the color signal; a color signal circuit that performs signal processing on the color signal; and a color signal circuit that is provided between the external input terminal section and each of the luminance signal circuit and the color signal circuit, and that is supplied to the external input terminal section. The composite video signal or the luminance signal forming it is supplied to the luminance signal circuit, and the composite video signal supplied to the external input terminal section or the color signal forming it is supplied to the color signal circuit. Signal switching capable of selectively taking a first state and a second state in which a luminance signal and a chrominance signal supplied to the external input terminal section are supplied to the luminance signal circuit and the chrominance signal circuit, respectively. means for determining whether the signal supplied to the external input terminal section is a composite video signal or a luminance signal and a color signal separated from each other, and depending on the determination result, controlling the signal switching means to A color television comprising: a switching control section that causes the first state or the second state to be taken; and an image display processing section to which respective outputs of the luminance signal circuit and the color signal circuit are supplied. Signal processing device.