KR0126263B1 - Video and sound muting apparatus - Google Patents

Abstract

a sound processing part(4) processing a sound signal from a broadcast signal; an image processing part(6) outputting a color difference signal(R'-Y, G'-Y, B'-Y) and a brightness signal(Y) by processing the image signal from the broadcast signal; a speaker outputting by amplifying the sound signal processed by the sound processing part(4) according to an amplification control signal; an input means(7) for a viewer to execute the system change of a television; an OSD generating means(10) outputting a RGB and a brightness signal(Y) to generate OSD corresponding to a change signal inputted by the input means(7); an OSD driving means(11) outputting a RGB and a brightness signal to drive OSD on the basis of the OSD output signal from the OSD generating means(10); a signal synthesis part(12) outputting to a CRT driving part(13) by synthesizing the color difference signal(R'-Y, G'-Y, B'-Y) and the brightness signal(Y) from the OSD driving means(7) and the image processing part(6); a microprocessor(9) outputting the system change signal to change system according to the input of the input means(7). The image and sound mute apparatus includes: a change signal detecting means(14) detecting the output of the system change signal from the microprocessor(9); a rectangular wave generating means(15, 16) outputting a rectangular signal to a brightness input terminal of the OSD driving means(11) when the system change is detected; and a switching means(17) dropping the amplification control signal applied to the amplifying part(5) and the RGB signal to the OSD driving means(11) to a ground level.

Description

Video and audio mute device when switching TV system

1 is a block diagram showing a video and audio mute device when switching the system of the television according to an embodiment of the present invention.

2 is a block diagram showing the configuration of the signal synthesis section in FIG.

* Description of the symbols for the main parts of the drawings *

1 antenna 2 tuner

3: IF circuit 4: Voice processing unit

5: amplifying unit 6: image processing unit

7: remote control unit 8: receiving unit

9: microprocessor 10: OSD generator

11: OSD driver 12: signal synthesis unit

13: CRT driving unit 14: switching signal detection unit

15: differential circuit 16: clipper circuit

17: switching unit 21: mixer

22: OR circuit 23: switching unit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to television receivers, and more particularly, to a video and audio mute apparatus capable of preventing on-screen image noise and pop noise from a speaker generated when switching a television receiver system.

In general, in a television receiver (hereinafter referred to as a TV), viewers can select various functions by switching the system as necessary.

For example, by selecting a desired function using the remote control device, it is possible to watch a program played by a video cassette recorder (VCR) or a cable TV (CA TV) using a TV.

However, when the system is switched to watch a VCR or CA TV while watching a broadcast program in this way, noise occurs in the output image on the CRT (Cathode-ray Tube) due to the transient state at the time of system switching. Impact sound is generated through the speaker.

In addition, such noise is generated not only in the function switching but also in the TV power supply on / off or the audio output in the stereo / mono switching, thereby acting as a factor which makes the viewer unpleasant.

Accordingly, the present invention was created in view of the above circumstances, and when switching the system of the TV, by muting the video and audio output through the CRT and the speaker, the system can be prevented from outputting noise due to transient state The object is to provide a video and audio mute device at the time of switching.

The video and audio mute apparatus at the time of system switching of a TV according to the present invention for realizing the above object comprises an audio processing unit for detecting and processing an audio signal from a broadcast signal, a video signal from the broadcast signal, and a predetermined color difference signal and An image processing unit for outputting a luminance signal, a speaker for amplifying and outputting the audio signal processed by the audio processing unit according to the amplification control signal, input means for the viewer to perform system switching of the television, and switching input by the input means OSD generating means for outputting RGB and luminance signals for OSD generation corresponding to the signal; OSD driving means for outputting RGB and luminance signals for OSD driving based on the OSD output signal from the OSD generating means; And outputting a synthesized color difference and luminance signal from the image processor to a CRT driver for forming a predetermined image on the CRT. A television receiver having a combining unit and a microprocessor for outputting a system switching signal for system switching in response to an input by the input means, comprising: switching signal detecting means for detecting an output of a system switching signal from the microprocessor; When the system switching is detected by the switching signal detecting means, the square wave generating means for generating a square wave signal for a predetermined period and outputting it to the luminance input terminal of the OSD driving means, which is switched in accordance with the output of the square wave generating means, to the amplifier. And a switching means for lowering the applied amplification control signal and the RGB signal to the OSD driving means to a ground level, wherein the signal synthesizing portion has a color difference signal and a luminance when only a blanking driving signal is input from the OSD driving means. It is characterized by blocking the output of the signal.

According to the present invention having the above-described configuration, when the viewer selects the system switch key of the remote control device for the system switch, the video and audio signals output through the CRT and the speaker are temporarily blocked. Therefore, the viewing environment of the viewer is improved.

Hereinafter, an embodiment according to the present invention will be described with reference to the drawings.

1 is a main structural diagram showing a video and audio mute apparatus when the TV system is switched according to an embodiment of the present invention.

In Fig. 1, reference numeral 1 is an antenna, 2 is a tuner for a broadcasting station, 3 is an intermediate frequency circuit (IF circuit) for outputting a composite video signal from a broadcast signal tuned by this tuner 2, 4 is An audio processing unit for detecting and processing an audio signal from the composite video signal output from the IF circuit 3, 5 is an amplification control signal from the microprocessor 9 described later for processing the audio signal processed in the audio processing unit 4; An amplifying unit for amplifying according to the present invention, and a sixth amplifying unit for outputting the color difference signal (R'-Y, G'-Y, B'-Y) and luminance signal (Y) from the composite video signal output from the IF circuit (3). The image processing unit for outputting.

In addition, reference numeral 7 denotes a remote control unit for the viewer to select system switching or predetermined function switching of the TV, 8 is a receiving unit for inputting infrared data from the remote control unit 7, and 9 is a receiving unit 8; An OSD that displays the status of the TV set by the viewer to the viewer by controlling the entire device based on code data for system switching or code data for various function selections. On Screen Display) A microprocessor that generates pattern data.

Further, reference numeral 10 denotes an RGB signal corresponding to OSD pattern data to be displayed on the CRT based on the control signal from the microprocessor 9 and the horizontal and vertical synchronizing signals H and V and the OSD clock CLK. An OSD generator for outputting the luminance signal (Y), 11 is a blanking driver 111 for executing the OSD blanking drive based on the luminance signal (Y) applied from the OSD generator (10) and the OSD generator (16) OSD driving unit 112 is configured to execute OSD RGB driving based on the RGB signal from the present invention. 12 is an RGB and luminance signal Y outputted from the OSD driving unit 11 and the image processing unit. A signal synthesizing unit for synthesizing and outputting the color difference signals R'-Y, G'-Y, B'-Y and the luminance signal Y output from (6), and 13 outputting from this signal synthesizing unit 12; The CRT driver drives the CRT based on the color difference signals RY, GY, BY and the luminance signal Y.

Reference numeral 14 denotes a switching signal detector for detecting system switching signals P1 to Pn output from the microprocessor 9, and 15 denotes a differential circuit for differentiating the detection signal output from the switching signal detector 14; 16 is a clipper circuit for clipping a differential output output from the differential circuit 15 to generate a predetermined rectangular pulse, and 17 is a clipper circuit 16 while a high level signal is output from the clipper circuit 16. Is applied to the transistors Q1 to Q3 and the amplifying unit 5 for dropping the RGB signal applied to the RGB driver 112 of the OSD driver 11 to the ground level during the high level period of the driving pulse output. A switching unit comprising a transistor (Q4) for muting the audio signal output to the speaker by lowering the amplification control signal to the ground level.

In addition, the output signal of the clipper circuit 16 is also applied to the blanking driver 111 of the OSD driver 11, so that the OSD driver 11 during the period in which the high level signal is output from the clipper circuit 16. As the luminance signal is inputted to the blanking driver 111, the signal is not input to the RGB driver 112, and only the luminance signal (blanking signal) is output from the OSD driver 11 to the signal synthesis unit.

When the RGB signal is not supplied from the OSD driver 11 and only the luminance signal Y is supplied, the signal synthesis unit 12 outputs the color difference signals RY, GY, and BY that are output to the CRT driver 13. By blocking the signal Y, the image is put into an image mute state in which no image is output on the CRT.

2 is a block diagram schematically showing the configuration of the signal synthesizing unit 12. The RGB and luminance signals Y from the OSD driver 11 and the color difference signals R'-Y, from the image processor 6 are shown in FIG. A mixer 21 for mixing G'-Y, B'-Y) and a fuss signal Y, an OR circuit 22 for ORing the RGB signals from the OSD driver 11, and the OSD driver 11 NPN transistors Q2 and PNP transistors Q6, which are turned on / off in accordance with the luminance signal Y from the output signal of the OR circuit 22, and the current paths between the collector and the emitter are connected in series, and When all of these transistors Q5 and Q6 are turned on and the low level switching signal is input, the water leveling unit lowers the color difference signal RY, GY, BY and the luminance signal Y output from the mixer 21 to the ground level. It is comprised including the part 23.

That is, when the RGB signal is not input from the OSD driver 11 (low level) and only the luminance signal Y is input (high level), the signal synthesizing unit 12 is turned on and the mixer 21 is turned on. ), The color difference signals RY, GY, BY and the luminance signal Y outputted to the CRT driving QN 13 fall to the ground level. Therefore, in this case, the image mute state in which no image is output on the CRT.

In addition, in the above-described configuration of FIG. 1, the input signal of the OR circuit 14 includes transient powers such as a TV power on / off signal, a TV / video switching signal, a stereo / mono switching signal, a TV / CA TV switching signal, and the like. Any signal that can generate noise from the CRT and the loudspeaker can be used by the state.

Next, the operation of the device having the above configuration will be described.

When the viewer performs system switching by using the remote controller 7, the microprocessor 9 controls the OSD generator 10 so as to generate the RGB and luminance signals Y for generating the OSD pattern corresponding to the viewer's selection. In addition to the output, the system switching signal is output through the output ports (P1-Pn).

When the system switch signal is output from the microprocessor 9, the output of the switch signal detector 14 is raised to a high level, and a rectangular pulse having a predetermined high level section is output from the clipper circuit 16.

In addition, the spherical pulses are turned on by the blanking driver 111 and the switching unit 17 of the OSD driver 11 so that all the transistors Q1 to Q4 of the switching unit 17 are turned on. The RGB signal applied to the OSD driver 11 from 10 drops to the ground level, while the amplification control signal applied to the amplifying unit 5 drops to the ground level, thereby performing voice muting.

In this case, the OSD driver 11 also inputs the RGB signal to the ground level, so that only the luminance signal is driven from the OSD driver 11 to the signal processor 12. Accordingly, as described above, the signal synthesizer The RGB and luminance signals Y outputted from the 12 to the CRT driver 13 are lowered to the ground level so that image muting is performed.

When the output signal of the clipper circuit 16 returns to the low level after a predetermined time has elapsed, all the transistors Q1 to Q4 of the switching unit 17 are turned off, and the amplification control signal of the predetermined level is supplied to the amplifying unit 5. In addition, the RGB signal corresponding to the OSD pattern data is input to the RGB driver 112 according to the selection of the viewer from the OSD generator 10 to the OSD driver 11.

Thus, the video and audio mute device is released to a normal operation state.

That is, in the above embodiment, since the video output and the audio output are cut off when the TV system is switched, noise can be prevented from being output to the speaker of the CRT due to the transient state.

In addition, the present invention is not limited to the above embodiments and various modifications can be made without departing from the technical gist of the present invention.

That is, for example, in the above embodiment, the video and audio muting device is executed on the basis of the system switching signal output from the microprocessor 9, but it is a driving signal for the relay for controlling the supply of main power in the television. It is also possible to configure the apparatus to operate when the voltage fluctuates to such a degree that the power supply fluctuation of the main power source can be detected to generate noise in video and audio output.

Also, in the above embodiment, image muting is performed by grounding the RGB input while supplying the luminance signal Y to the OSD driver 11, but this is performed by the color difference signals R'-Y and G 'of the signal synthesis unit 12. The same effect can be obtained by supplying the luminance signal Y while grounding the -Y, B'-Y) inputs.

As described above, according to the present invention, the video and audio mute apparatus is executed in the transient state as in the system switching, thereby preventing noise from being output to the CRT or the speaker due to the transient state in the system switching.

Claims (3)

An audio processing unit 4 for detecting and processing an audio signal from the broadcast signal, and processing a video signal from the reunion signal to provide predetermined color difference signals (R'-Y, G'-Y, B'-Y) and luminance signals ( Y) an image processing unit 6 for outputting, a speaker for amplifying and outputting the audio signal processed by the audio processing unit 4 in accordance with the amplification control signal, and input means for the viewer to perform a tele-system switching. ), An OSD generating means (10) for outputting an RGB and a luminance signal (Y) for OSD generation corresponding to the switching signal input by the input means (7), and an OSD output signal from the OSD generating means (10). OSD driving means (11) for outputting RGB and luminance signals (Y) for driving the OSD on the basis of the above, and color difference signals (R'-Y, G ') from the OSD driving means (11) and the image processor (6). A signal synthesizing unit 12 for synthesizing -Y, B'-Y) and luminance signals Y and outputting them to the CRT driver 13 for forming a predetermined image on the CRT; In a television receiver having a microprocessor (9) for outputting a system switch signal for system switch in accordance with an input by the output means (7), the switch for detecting the output of the system switch signal from the microprocessor (9). When the system switching is detected by the signal detecting means 14 and the switching signal detecting means 14, the square wave generating means for generating a square wave signal for a predetermined period and outputting the square wave signal to the luminance input terminal of the OSD driving means 11 ( 15 and 16 are switched according to the output of the square wave generating means 15 and 16 to drop the amplification control signal applied to the amplifier 5 and the RGB signal to the OSD driving means 11 to the ground level. And a switching means (17), wherein said signal synthesizing portion (12) is said OSD driving means (11). OSD generating means for outputting RGB and luminance Y for the OSD, and color difference signals R'-Y, G'-Y, B'-Y from the RGB and luminance signals Y and the composite signal for the OSD. And a television with signal synthesizing means for synthesizing and outputting the luminance signal (Y), comprising: transient detection means for detecting a transient state of the television, and for a predetermined level of OSD on the basis of detection results by said transient state detection means; And a signal generating means for generating a luminance signal and inputting the signal to the signal synthesizing means. 3. The apparatus of claim 2, further comprising suing means for leveling by the OSD luminance signal output from the signal generating means to ground the level of the OSD RGB signal input terminal of the signal synthesizing means to a ground level. A video muting device for a TV.