KR100247087B1 - Burst position amending device of tv - Google Patents

Abstract

According to the present invention, a burst position adaptive correction of a television which detects an inconsistent state of a signal position with respect to a burst signal transmitted superimposed on a television broadcast signal and performs a correction operation for adaptively matching the signal position corresponding to the detected state is performed. Provide the device.

To this end, the present invention detects a video amplification unit 4 for performing signal amplification for a video signal according to television broadcasting detected by the video detector 2, and a burst signal for a video signal processing operation of the video signal. In the television comprising a burst detection / amplification section 8 for amplifying the signal and a burst phase detection section 14 for generating a burst phase detection voltage whose voltage value is variable in correspondence with the detected phase of the burst signal. A phase detecting means 30 for receiving a horizontal synchronizing signal separated from the video signal by the synchronizing separator 10 and a reference pulse signal divided by 1 / N for the horizontal synchronizing signal, and performing a phase detecting operation; Reference pulse generation means 32 and phase detection means 30 which receive a signal and generate 1 / N division processing based on the clock signal CK to generate a reference pulse signal for adaptive compensation of the burst signal. sword The voltage-controlled oscillation means 34 generating the clock signal CK by receiving the wave output signal and performing the oscillation operation is synchronized with the clock signal CK generated from the voltage-controlled oscillation means 34. Control pulse generating means (36,38) for generating switching control pulses for progressively matching the signal position, and switching control pulses from the control pulse generating means (36,38) are applied to adjust the signal position of the burst signal. Control switch means (40) for switching the state in which the video signal from the image detector (2) is supplied to the image amplifier (4) for an adaptive correction operation for matching, and the burst phase detection unit (14). The burst phase detection voltage generated from the controller recognizes a voltage value changed as the signal position of the burst signal is mismatched, and adaptively adapts to the control pulse generating means 36, 38 to the variable state of the voltage value. And a control means 42 for controlling the generation of the switching control pulse is characterized in that configured.

Description

Burst Position Adaptive Compensator for Television

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a burst position adaptive correction apparatus for a television, and more particularly, to a burst signal transmitted intermittently for phase control of a color sub carrier of a broadcast signal in a television. If the signal position of the signal is mismatched, it relates to a burst position adaptive correcting apparatus for a television for adaptively compensating for the mismatched state.

In general, a television that receives and reproduces a television broadcast signal transmitted in an airwave form allows a television broadcast signal having a color broadcast transmission method such as, for example, NTSC, to be received and reproduced through a CRT screen. The television broadcast signal is composed of a combination of a luminance signal and a color signal having 525H (H is an image scanning period) of two fields (that is, one screen), and the odd field and the even field are approximately. It is synchronized by the 3H vertical synchronization signal included in the vertical retrace period of 21H, and is synchronized by the horizontal synchronization pulse every 1H.

In addition, such a television broadcast signal has a burst of 3.58 MHz at the rear end of the back porch in the horizontal retrace period so that the receiving side can generate a color subcarrier frequency signal of 3.58 MHz that is suppressed and transmitted on the transmission side. The signals are intermittently superimposed and transmitted.

FIG. 1 is a block diagram showing a configuration of a video reproduction output of a conventional TV. According to the drawing, the image detector 2 is tuned from a tuner (not shown), and is converted into an intermediate frequency form. Then, the video signal is detected and separated from the intermediate frequency-amplified television broadcast signal. The video amplifier 4 amplifies the detected video signal in multiple stages, and adjusts the contrast of the pedestal clamp operation and the luminance signal. Operation such as brightness adjustment is performed.

Further, according to the drawing, the band amplifier 6 separates the carrier color signal from the video signal from the video amplifier 4 and performs band amplification to have a predetermined band pass characteristic for color signal processing. The / amplifier 8 receives the horizontal synchronization signal separated from the synchronization separator 10 and detects the burst signal from the carrier color signal subjected to the band amplification processing by the band amplifier 6 and detects the color signal. In the opportunity path 12, the detected burst signal is oscillated through an oscillation means such as a crystal oscillator to generate a color subcarrier signal of 3.58 MHz so that the chromaticity of the ACC (Automatic Chroma Control) circuit 18 can be generated. The amplitude adjustment control operation between the signal and the luminance signal and the mixing prevention operation of the color noise for forming the black and white image by the luminance signal of the color killer unit 16 are made possible.

On the other hand, the burst phase detection unit 14 generates a voltage value variable according to the phase of the burst signal detected from the burst detection / amplifying unit 8 to adjust the oscillation phase for the color synchronization circuit 12. I'm trying to.

In addition, the color demodulator 20 receives the image signal amplified by the band amplifier 6 and performs color demodulation based on the color subcarrier frequency from the color synchronization circuit 12. 22 is driven by the luminance signal from the image amplification section 4 to perform an output drive for the color demodulation output from the color demodulation section 20 to display the CRT 24 screen by the R / G / B color signal. The color image is reproduced on the image.

However, such a television generates a color subcarrier frequency through detection of a burst signal superimposed on a video signal so that color demodulation operation and color and tint adjustment can be performed. If the signal is distorted or the signal position of the burst signal is departed due to the weak signal reception state, there is a problem that the image reproduction characteristic becomes unstable because the color disappears or the tint becomes unstable in the image on the CRT screen.

Accordingly, the present invention has been made in view of the above circumstances, and is intended to detect a mismatch of signal positions with respect to a burst signal transmitted superimposed on a television broadcast signal and to adaptively match signal positions corresponding to the detected states. It is an object of the present invention to provide a burst position adaptive correcting apparatus for a television that performs a correcting operation.

In order to achieve the above object, according to the burst position adaptive correcting apparatus for a television according to the present invention, an image amplifier for performing a signal amplification for a video signal according to a television broadcast detected through an image detector, and an image of the video signal. A burst detection / amplification section for detecting and amplifying a burst signal for a signal processing operation, and a burst phase detection section for generating a burst phase detection voltage whose voltage value is changed in correspondence with a phase of the detected burst signal. In a television, a phase detecting means for receiving a horizontal synchronous signal separated from a video signal by a synchronous separator and a reference pulse signal divided by 1 / N for the horizontal synchronous signal to perform phase detection operation; 1 / N division processing based on the clock signal to generate a reference pulse signal for adaptive compensation of the burst signal. Voltage controlled oscillation means for generating a clock signal by receiving the quasi-pulse generating means, the detection output signal from the phase detecting means, and generating a clock signal, and a signal of the burst signal synchronized with the clock signal generated from the voltage controlled oscillating means. The control pulse generating means for generating a switching control pulse for gradually matching the position, and the image for an adaptive correction operation for matching the signal position of the burst signal by receiving a switching control pulse from the control pulse generating means. Control switch means for switching the state in which the video signal from the detector is supplied to the video amplifier, and a voltage value of the burst phase detection voltage generated from the burst phase detection unit, the signal position of the burst signal being mismatched. Recognizes and adaptively adapts the control pulse to the variable state of the voltage value. Provided is a burst position adaptive correcting apparatus for a television, comprising control means for controlling generation of switching control pulses to the generating means.

According to the present invention configured as described above, a detection occurs in accordance with the burst phase detection state from the burst phase detection means by the signal position of the burst signal inserted and transmitted in the back porch among the video signals of the television broadcast in the television. Matching based on voltage ensures accurate color and tint adjustments.

1 is a block diagram showing a configuration state for video reproduction output of a conventional general television;

2 is a block diagram showing a burst position adaptive correcting apparatus for a television according to the present invention;

3 is a timing chart illustrating an operation for adaptively correcting the position of a burst signal in the burst position adaptive correction device shown in FIG. 2 according to a preferred embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

2: image detector, 4: image amplifier,

6: band amplifier, 8: burst detection / amplification,

10: synchronous separation unit, 14: burst phase detection unit,

30: phase detector, 32: divider,

34: voltage controlled oscillator, 36: reset pulse generator,

38: Burst flag pulse generator, 40: control switch unit,

42: control unit.

Hereinafter, the present invention configured as described above will be described in detail with reference to the accompanying drawings.

2 is a block diagram showing a burst position adaptive correcting apparatus for a television according to the present invention, in which the image detector 2, the image amplifier 4, the band amplifier 6, and the burr are shown. The streak detection / amplification section 8, the synchronous separation section 10, and the burst phase detection section 14 are given the same reference numerals as those of FIG. 1, and detailed description thereof will be omitted.

In the apparatus of the present invention according to the same figure, reference numeral 30 is a phase for receiving a horizontal synchronization signal from the synchronization separator 10 and performing phase detection operation for a PLL operation based on the reference pulse signal Href. The detector 32 is applied to the clock detector CK generated as a result of the voltage-controlled oscillation operation and divides by the 1 / N division period by the PLL method, and the reference pulse signal Href is applied to the phase detector 30. 34 represents a voltage controlled oscillator which generates a clock signal CK by performing a voltage controlled oscillation operation in accordance with the phase detection operation of the phase detector 30.

The reference pulse signal Href generated based on the division ratio of 1 / N set in the frequency divider 32 corresponds to a period from the horizontal retrace period of the image signal to a period before the effective image scan period in accordance with the effective image region. Has a period.

Further, reference numeral 36 denotes a reset pulse for matching the signal position of the burst signal by receiving a control signal from the controller 42 described later in synchronization with the clock signal CK from the voltage controlled oscillator 34. 38 shows a generated reset pulse generator, and 38 denotes a burst flag pulse (BFP) for matching the signal position of a burst signal by being applied within the pulse period of the reference pulse signal Href by receiving the reset pulse. A burst flag pulse generator is shown.

Reference numeral 40 denotes a signal position of the burst signal included in the video signal from the video detector 2 by being driven by a burst flag pulse (BFP) from the burst flag pulse generator 38. A control switch section for adjusting an input period of a signal through a correction operation for matching.

Reference numeral 42 denotes the reset pulse generator based on the voltage value of the burst phase detection voltage BPD (see FIG. 3) generated in accordance with the phase detection result of the burst signal from the burst phase detection unit 14. 36 shows a control unit for generating a control signal for controlling the signal position matching of the burst signal.

Here, the burst phase detection voltage BPD generated from the burst phase detection unit 14 generates a voltage having the lowest voltage value when the phase of the burst signal is matched, and when the phase of the signal is completely out of phase. The voltage having the highest voltage value is generated, and the controller 42 gradually generates a control signal for correction control based on the voltage value of the burst phase detection voltage BPD. .

Next, the operation of the present invention made as described above will be described in detail with reference to the accompanying drawings.

First, when an image signal tuned from a tuner (not shown) and subjected to intermediate frequency amplification is detected and separated through the image detector 2, the image amplifier 4 performs a multi-stage signal amplification operation for the image signal. In addition, a brightness adjustment operation and a contrast adjustment operation are performed on the brightness signal, and the band amplifier 6 performs a band amplification operation for separating a carrier color signal from the video signal to have a predetermined band pass characteristic. The burst detection / amplification unit 8 receives the horizontal synchronization signal extracted from the synchronization separation unit 10 and separates the burst signal from the band-amplified video signal to amplify the burst signal. The burst phase detection unit 14 In FIG. 3, a burst phase detection voltage BPD having a voltage value based on a phase difference is generated according to a result of detecting the phase of the detected burst signal (see FIG. 3).

At this time, the phase detector 30 receives the horizontal synchronization signal extracted from the synchronization separator 10 and performs phase detection by the reference pulse signal Href generated from the divider 32. The control oscillator 34 generates the clock signal CK according to the phase detection operation result of the phase detector 30.

On the other hand, the controller 42 receives the burst phase detection voltage BPD generated from the burst phase detection unit 14 and generates a control signal for matching the signal position of the burst signal based on the voltage value. As a result, the reset pulse generator 36 is synchronized with the clock signal CK and receives a control signal from the control unit 42 to generate a reset pulse. The burst flag pulse generator 38 generates a reset pulse. As shown in FIG. 3, the reset pulse generates a burst flag pulse BFP having a pulse period corresponding to the pulse period of the reference pulse signal Href, and the burst flag pulse BFP. Is generated so that the pulse period is gradually shifted to follow the signal position of the burst signal in accordance with the reset pulse from the reset pulse generator 36.

As a result, the control switch unit 40 receives the burst flag pulse (BFP) from the burst flag pulse generator 38 and is switched and driven so as to be included in the image signal from the image detector 2. The timing for matching the signal position of the test signal is adjusted and output to the image amplifying section 4 side.

According to the present invention made as described above, the burr detects a mismatch state of the burst signal on the basis of the voltage value of the detected voltage according to the burst phase detection and performs a correcting operation for matching the signal position. It is advantageous in that accurate image reproduction can be achieved by preventing color or tint fluctuations or abnormal conditions caused by mismatching of streak signals.

Claims (2)

An image amplifier 4 for amplifying a video signal according to the television broadcast detected by the image detector 2, and a burr for detecting and amplifying a burst signal for an image signal processing operation of the video signal. In a television equipped with a burst detection / amplification section (8) and a burst phase detection section (14) for generating a burst phase detection voltage whose voltage value varies in correspondence with the detected phase of the burst signal, A phase detecting means 30 which receives a horizontal synchronizing signal separated from the video signal by the synchronizing separator 10 and a reference pulse signal divided by 1 / N for the horizontal synchronizing signal and performs phase detection operation; Reference pulse generating means (32) for receiving the horizontal synchronization signal and generating a reference pulse signal for adaptive compensation of a burst signal by performing 1 / N division processing based on a clock signal (CK); A voltage controlled oscillation means 34 which receives the detection output signal from the phase detection means 30 and performs an oscillation operation to generate a clock signal CK, Control pulse generating means (36,38) for generating a switching control pulse for gradually matching the signal position of the burst signal in synchronization with the clock signal (CK) generated from the voltage controlled oscillating means (34); The image signal from the image detector 2 is applied to the image amplifier 2 for an adaptive correction operation for receiving the switching control pulses from the control pulse generating means 36 and 38 to match the signal position of the burst signal. Control switch means (40) for switching the state supplied to (4), The burst phase detection voltage generated from the burst phase detection unit 14 recognizes a voltage value which is changed as the signal position of the burst signal is mismatched, and adaptively adjusts the control pulse generating means 36 to the variable state of the voltage value. And a control means (42) for controlling the generation of the switching control pulses for < RTI ID = 0.0 > 38. < / RTI > The method of claim 1, wherein the 1 / N division ratio of the reference pulse signal generated by the reference pulse generating means 32 is set to include a period before the effective video scanning period from the horizontal retrace period of the video signal. A burst position adaptive correction device for television, characterized by the above-mentioned.

Images