JPS61502439A - Color saturation control circuit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Color saturation control circuit TECHNICAL FIELD The present invention relates to the processing of color video signals, and in particular to video monitors and It concerns the processing of color video signals in aircraft and television receivers. It is not limited to that.

When using a color video monitor, the input signal may be, for example, a red signal from a camera. , green and blue (RGB). television receiver odor In other words, the RGB signal is derived from a composite human input signal.

The object of the present invention is to provide a saturation control circuit with which the saturation of RGB colors can be changed. The goal is to provide the following.

According to the present invention, the video signal color saturation control circuit receives an RGB video signal. means to Induces luminance and color difference signals from the received RGB signals, and calculates all levels of color difference signals. means for controlling the saturation of the color in a controlled manner; and means for inducing a KGB signal with controlled saturation from the controlled color difference signal. .

One television display according to the invention with reference to the accompanying drawings showing a block schematic diagram of the circuit. The receiver saturation control circuit is described below.

Now referring to the drawing, the saturation circuit is the first one. second and third nodes 1, 2 and Contains 3.

The input node 1 is connected via a buffer amplifier 4 and a series connected resistor 5. is connected to point 6. Input node 2 includes a buffer amplifier 7 and a series connected resistor 8 is connected to point 6 via. Input node 3 is connected to buffer amplifier 9 and series resistor 1 0 to point 6.

The common point 6 is also connected to two variable gain differential amplifiers 11, 12. loose The output of the amplifier 4 is connected to the non-inverting input of the differential amplifier 11. buffer amplifier The output of 9 is connected to the non-inverting input of the differential amplifier ratio.

The non-inverting output of the differential amplifier 11 is connected to the first output of the adder 13. Differential increase The inverting outputs of the width converter 11 and Tsuji are connected to a resistor network 14, and the resistor network 14 The output of is connected to the first output of adder 15. The non-inverting output of the differential amplifier ratio is It is connected to the first input of adder 16.

The second power of each of adders 13, 15, and 16 is supplied through a unity gain buffer amplifier 17. and is connected to common point 6.

The outputs of adders 13, 15 and 16 are connected to output nodes 18, 19 and are connected to each other.

When using the circuit, the R, G and B signals are applied to input nodes 1, 2 and 3. are applied respectively. The R signal is sent directly from the output of the buffer amplifier 4 to the non-signal of the differential amplifier 11. Applied to the inverting input. The B signal is directly connected to the differential amplifier ratio from the output of the buffer amplifier 9. Applied to non-inverting input.

Resistors 5, 8 and 10 are 3.33 kΩ, 1.69 is Ω and 9.1 is Ω. , the RGB signals are combined in the exact ratio at point 6, using the well-known formula below: Generate a luminance signal according to: Ey” 0.3 ER+ 0.59 E(H+ 0.11 EB Therefore, differential The output of the amplifier 11 is the (R-Y) signal, and the output of the differential amplifier is the (R-Y) signal. This is the number. The outputs of differential amplifier 11 and U are combined in a resistor network 14; The (a-y) signal is generated at the output of the network according to the well-known formula: ECEY=-0,51 (EREy) 0.186 (Ea Ey) (RY), ( G-Y) and (B-Y5 signals are respectively input to adders 13, 15 and 16. is combined with the Y signal from point 6 to generate R, G and B signals, and these signals appear at output nodes 1B, 19 and 1, respectively.

By changing the gains of differential amplifiers 11 and 12, adders 13, 15 and and the amplitudes of the (R-Y), (G-Y) and (B-Y) signals applied to changes and therefore occurs at output nodes 1g, 19 and gloss respectively Change the color saturation of the color output signals R, G and B.

The gain of the differential amplifier 11 and the differential amplifier 11 that controls the saturation of the circuit is controlled by the microprocessor ( (not shown).

If desired, use the (RY) and (B-Y) signals as described above. Instead of inducing the (G-Y) signal through a resistive network, its non-inverting input is buffered. a third differential amplifier connected to the output of amplifier 7 and having its inverting input connected to point 6; It will be appreciated that the (G-Y) signal may be derived using a width transducer.

The television receiver control circuit described above can be applied to any video device, e.g. a video monitor. It will be understood that it can also be used.

It will also be appreciated that the control circuits described above are convenient to incorporate into integrated circuits. Probably.

Figure 1 National VA investigation report ANNEX To ='= INTERNAT 0NAL 5EARCHREP ORT 0N INTERNATIONAL AB? LICk71ON No, E’Cτ/Ill, B 85100245 (SA 9839)

Claims (6)

[Claims] 1. Means for receiving RGB video signals and determining brightness and color from the received RGB signals Induce the difference signal and control the level of the color difference signal to control color saturation means and and means for inducing saturation-controlled RGB signals from the controlled color difference signals. Video signal color saturation control circuit. 2. The means for inducing the luminance and color difference signals converts the received RGB signal into a luminance signal. The foregoing claims include buffer and compiler means for combining in proportions such that Circuit according to the first term. 3. The means for inducing the luminance and color difference signals further includes one of the luminance signal and the RGB signal. a first signal receiving a first signal and generating a first level controlled signal representative of a difference therebetween; differential amplifier means; a second level that receives a second signal of the luminance signal and the RGB signal and represents the difference therebetween; second differential amplifier means for generating a controlled signal; a third level controlled color difference representing the difference between the luminance signal and a third signal of the RGB signals; color difference signals from the first and second differential amplifier means in such a ratio as to generate a signal; and a compiler means for combining A circuit according to claim 2. 4. The guiding means includes first, second and third summing means and includes a luminance signal and a level controlled Each one of the color difference signals is received and summed to form a saturation controlled RGB signal. A circuit according to claim 1, 2 or 3 which generates a signal. 5. An integrated circuit incorporating any circuit according to any one of the above items. 6. Includes a circuit according to any one of claims 1 to 4. Video display equipment.