JPS6330833B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a signal processing device in a color television receiver.

Conventional configurations and their problems In response to the development and practical application of a wide variety of new information services and new transmission methods, recent color television receivers are not only capable of displaying conventional broadcast programs. It has come to be connected to various video and audio devices, personal computers, etc., input or output necessary information, and used as a display device for video information.

In order to facilitate connection with such various devices, multi-connectors as shown in Figure 1 have come to be used uniformly, and color television receivers equipped with these terminals are now commercially available. .

FIG. 1 shows a schematic diagram of a multi-connector adopted in France and Western Europe (SCART or CENELEC standards), and shows the relationship with the signals applied to each terminal.

FIG. 2 shows a conventional example in which this terminal is used to connect, for example, a character multiplex reception adapter device and a color television receiver. In FIG. 2, a signal input from the antenna of a color television receiver 10 is amplified and detected by a tuner 11, a VIF amplifier, and a video detector 12 to obtain a composite color television signal. This signal is further subjected to necessary amplification and processing in a video amplifier 13 and a color signal processing circuit 14, respectively, to obtain R, G, and B primary color signals.

In the color television receiver having the multi-connector, the R, G, and B signals obtained by the color signal processing circuit 14 are supplied to a signal switching circuit 15. Further, this signal switching circuit 15 includes:
R, G, and B signals are supplied from the outside through terminals 3a, 4a, and 5a of the multi-connector 1a. The signal switching circuit 15 receives R from the color signal processing circuit 14,
The G, B signal and the R, G, B signal supplied from the outside via the multi-connector 1a are switched and outputted, or both are mixed and outputted. The output of the signal switching circuit 15 is a cathode ray tube (hereinafter referred to as CRT).
The video information is supplied to an output amplification stage 16 that drives the video signal, and the video information is displayed on a CRT 17 via this stage.

On the other hand, the video signal outputted from the video amplifier 13 of the color television receiver 10 to the terminal 2a of the multi-connector 1a is received by the terminal 2b of the multi-connector 1b of the character multiplex signal receiving adapter 20, and is transmitted directly to the synchronous separation circuit. 21, a signal containing character information and a synchronization signal are sent to a character signal processing circuit 22. The character signal processing circuit 22 extracts and decodes the required information based on commands from the keyboard or remote control transmitter 24, and converts the signal from the memory 23 into R,
Output in the form of G and B primary color signals. This output signal is transmitted to terminals 3b, 4b of multi-connector 1b,
5b, is connected to the terminals 3a, 4a, 5a of the multi-connector 1a on the mulberry receiver side, and is added to the signal switching circuit 15 as shown.

The conventionally used signal switching circuit 15 is actually composed of an integrated circuit, and has a configuration as shown in the main block diagram of FIG. 3.

In FIG. 3, terminals 31a, 32a, 33a
R, G, and B signals are applied to the terminal 31 from the color signal processing circuit 14 shown in FIG.
b, 32b, 33b are supplied with the R, G,
A B signal is supplied. These signals are applied to an R signal switching stage 41, a G signal switching stage 42, and a B signal switching stage 43, respectively, as shown in FIG. These switching stages are controlled by a switching signal or a data blanking signal applied from the terminal 6a of the multi-connector 1a shown in FIG. 2 to the terminal 34 in the block diagram of FIG. That is, when the voltage at the terminal 34 becomes High level, the R, G,
The B signal is cut off and the signals from the terminals 31b, 32b, and 33b are transferred to the next stage. In the case of character multiplex signal reception, this data blanking signal is
As shown in the figure, the signal is supplied from the character signal processing circuit 22.

The outputs of the R signal switching stage 41, the G signal switching stage 42, and the B signal switching stage 43 are respectively outputted from contrast adjustment stages 44, 45, 46, brightness adjustment stage 47,
48, 49, and output stages 50, 51, 52 including clamping and blanking functions as necessary, the R output signal, G output signal, and B output signal are output to terminals 37, 38, and 39, respectively.

As mentioned above, the contrast adjustment and brightness adjustment functions are included in the block diagram of FIG. signal or demodulated R-Y and B-Y
There is a problem in that the R, G, and B signals supplied from the multi-connector 1a cannot be controlled at all by merely adjusting the color difference signals.

This is not a problem in the case of pulsed signals such as traditional teletext signals, but in the future, new information media will
A problem arises where the color saturation cannot be adjusted when the signal is supplied via multiple connectors. In other words, in the conventional circuit shown in Fig. 3, although it is possible to adjust the image contrast by adjusting the amplitudes of the R, G, and B signals, the color saturation is adjusted separately from the image contrast. I can't. This is because the R, G, and B signals directly represent the brightness of each color in the image, and do not represent the amount of coloring of each color separately from the luminance signal, which represents the brightness of the image, like color difference signals. It is from. When displaying characters, etc. using a pulse signal such as a teletext signal, there is no intermediate tone, and the display mode is to either display the characters, etc. in a predetermined color (for example, the "1" part of the pulse), or It is only a matter of whether or not to display (for example, the "0" part of the pulse), and the coloring amount of the displayed part immediately becomes the brightness, so there is no need to adjust the color saturation.
You only need to be able to adjust the brightness of the display area, so use the method described above to adjust the contrast adjustment stage 4.
4, 45, 46, the brightness adjustment stage 47,
Adjustment is also possible by changing the DC levels of the R, G, and B signals at 48 and 49. However, analog format R, G,
When a B signal is input and a moving image or the like is displayed, it is necessary to be able to independently adjust the color saturation in addition to the contrast and brightness of the image. In other words, if you want to display halftones as well, you can adjust only the color saturation without changing contrast or brightness.
It is desirable to be able to adjust to any desired color saturation. However, in the configuration shown in FIG. 3, as mentioned above, changing the amplitudes of the R, G, and B signals causes the contrast itself to change, resulting in the problem that only the color saturation cannot be adjusted. be.

OBJECTS OF THE INVENTION The present invention avoids such conventional problems and provides a means for making desired color saturation adjustment even when analog format signals are supplied from the R, G, B input terminals of a multi-connector. It is something to do.

Structure of the Invention In the present invention, in view of the fact that the color saturation cannot be controlled using the R, G, and B primary color signals supplied to the receiver from the outside, the Obtain the R-Y and B-Y color difference signals, adjust the color product signals with the color saturation adjuster of the receiver, and then convert them into R, G, and B signals again and connect them to the interface circuit. It is characterized by the fact that it is made as follows.

DESCRIPTION OF THE EMBODIMENTS FIG. 4 shows an embodiment of the principle configuration of the device of the present invention that realizes the above-mentioned functions in a system diagram of main parts.
In FIG. 4, R, G, and B signals are supplied from terminals 51a, 51b, and 51c, and a matrix circuit 53
to go into. The matrix circuit 53 implements a matrix such as the above equation (1) in a circuit manner. For example, as is well known, the outputs of differential amplifiers as shown in FIG. 5 are added together via a suitable resistor. That is, the terminal 51
An R signal is applied between terminals 51b and 51a', and terminals 51b and 51a' are
It is assumed that a G signal is applied between terminals 1b' and a B signal is applied between terminals 51c and 51c'. These signals are transmitted through transistors 71a, 71a' and 71b, respectively.
and 71b', and 71c and 71c'. If the inputs 51a, 51b, and 51c are taken as a reference, a signal in phase with the R signal input is obtained from the collector of the transistor 71a, a signal in the opposite phase is obtained from the collector of the transistor 71a', and similarly, a signal in phase with the G signal is obtained from the collector of the transistor 71b. A signal of opposite phase is obtained from the collector of the transistor 71b',
An in-phase signal is obtained from the collector of the transistor 71c, and an opposite-phase signal is obtained from the collector of the transistor 71c'.

Therefore, these differential amplifier output signals are connected to appropriate resistors 72a, 72b, 72c and 72 as shown.
5 and a buffer amplifier 7.
A Y signal can be obtained at the output terminal 52a through 8, and similarly suitable resistors 73a, 73b, 73c
and 76, and a buffer amplifier 79
The R-Y signal can be obtained at the output terminal 52b through the buffer amplifier 80, which is synthesized by the illustrated circuit consisting of suitable resistors 74a, 74b, 74c and 77, and the B-Y signal is output at the output terminal 52c through the buffer amplifier 80. get.

As above, from R, G, B signals, Y, R-
After converting into the Y, B-Y signal, the Y signal obtained at the terminal 52a as shown in FIG.
The R-Y signal obtained at
In addition, the B-Y signal is applied to variable gain adjustment means 56. The RY signal passed through the variable gain adjustment means 55 and the BY signal passed through the variable gain adjustment means 56 are G.
-Y matrix circuit 61, and as is well known, the G-Y signal is obtained from the relationship of equation (2).

(G-Y)=-[0.30/0.59(RY)+0.11/0.59(
B-Y)] ...(2) As a result, three color difference signals of R-Y, G-Y and B-Y are obtained, and both are sent to the terminal 65 and the broken line 58 by the color saturation adjuster 66. The saturation degree (amplitude) can be adjusted by These color difference signals are sent to adder circuits 62a, 62b, and 62b, respectively, using a known method.
At 62c, it is combined with the Y signal supplied via the variable gain adjuster 54 and is again output to the terminals 62a, 62c.
R, G, and B signals are obtained at 62b and 62c.

FIG. 6 is a block diagram of essential parts of an embodiment in which the present invention is applied to a color television receiver. In the figures, the same element blocks as those in Figures 2 and 4 described above are indicated by the same numbers.
Avoid duplication of explanations.

FIG. 6 shows an embodiment in which two systems of R, G, and B signals are supplied. Data blanking signal BL ₁ and terminals 3a and 4 of multi-connector 1a
A switching circuit 90 switches between R ₂ , G ₂ , B ₂ and data blanking signal BL ₂ supplied from a, 5 a, and 6 a. In the illustrated example, the teletext decoder 2
Each signal from 0 is transferred from contact 91a to 91b, 92a
From 92b, 93a to 93b, 94a to 94
b, of which the R, G, and B signals from the teletext decoder 20 are connected to the matrix circuit 53.
to go into. As described above, the Y signal, R-Y signal, and B-Y signal are outputted from the matrix circuit 53, and are outputted from the terminals 64a, 64b, and 64c via the variable gain adjustment means 54, 55, and 56, respectively, to the R, G, and B matrix circuits. Enter 30. This R, G, B matrix circuit 30 is a block 30 surrounded by a broken line in FIG. 4, and again outputs R, G, B signals. The R, G, and B signals thus obtained are added to the conventional signal switching circuit 15 shown in FIGS. 2 and 3 together with the R, G, and B signals supplied from the color signal processing circuit 14, and The output amplification stage 16 drives the CRT 17 to display the desired images or characters.

In FIG. 6, the color saturation adjuster 19 allows the color signal processing circuit 14 to adjust not only the signals received from the antenna but also the R, G, and B signals supplied from the multi-connector 1a and the like. Also, if necessary, the variable gain adjustment circuit 5
4, it is also possible to adjust the contrast of the Y signal components of the R, G, and B signals.

Effects of the Invention As described above in detail, according to the present invention, in the conventional R, G, B interface circuit, the color saturation of the R, G, B signals supplied from the multi-connector terminal can be freely controlled. be able to. In the near future, the output of a satellite broadcast receiving adapter that will be launched will also be able to be connected directly (via a multi-connector) to a receiver equipped with this circuit using R, G, and B signals. Additionally, it can interface with various analog R, G, and B signals provided by future new media equipment.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of a multi-connector, Figure 2 is a block diagram for explaining a conventional example, and Figure 3 is an explanation of the R, G, B signal switching circuit used in the main part block diagram of Figure 2. 4 is a block diagram showing the configuration of a signal processing device for a color television receiver according to an embodiment of the present invention, and FIG. 5 is a circuit diagram showing an example of the configuration of a matrix circuit used in FIG. 4. 6 are block diagrams of an embodiment that uses the same device to supply two systems of R, G, and B signals. 53...Matrix circuit, 30...R, G, B
Matrix circuit, 54, 55, 56... variable gain adjustment circuit for Y signal, RY signal, B-Y signal, respectively, 66... color saturation adjuster.

Claims (1)

[Claims] 1 Input the R, G, B3 primary color signals, and
B signal to Y signal and (RY) and (B-Y)
a first matrix circuit for converting into a color difference signal, an amplitude adjusting means for adjusting the amplitude of the (R-Y) signal and the (B-Y) signal, respectively;
a second matrix circuit for extracting R, G, and B3 primary color signals from the Y) signal and the (B-Y) signal, and the (RY) signal and (B-Y) whose amplitude is adjusted by the amplitude adjusting means. A color television receiver characterized in that the signal and the Y signal whose amplitude is adjusted as necessary are converted into R, G, and B signals in the second matrix circuit and outputted, and the signals are supplied as a color video display signal. Signal processing device.