KR19980052938A - White Balance Automatic Control of Television Receiver - Google Patents

Abstract

The present invention relates to an apparatus for automatically adjusting white balance in a television receiver capable of analyzing a level of an RGB color signal generated from a color difference signal and automatically adjusting white balance based on the analysis result. A television receiver having an image processing unit for generating and outputting a signal and a color signal outputting unit for generating and outputting a corresponding color signal based on the color difference signal; A reference level data storage unit for storing reference level data of a color signal, a color signal level detector for detecting a level of the color signal from the color signal output from the color signal output unit, and detected by the reference level data and the color signal level detector A comparator for comparing detection levels, an analog signal generator for generating and outputting an analog signal corresponding to the result of the comparator, and synthesizing the color difference signal and a corrected color signal input from the analog signal generator and outputting the synthesized color signal to the color signal output unit. Characterized in that it comprises a color difference signal correction for.

Description

White Balance Automatic Control of Television Receiver

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television receiver, and more particularly, to an apparatus for automatically adjusting white balance in a television receiver, which is capable of analyzing a level of an RGB color signal generated from a color difference signal and automatically adjusting the white balance based on the analysis result.

1 is a block diagram illustrating an operation of adjusting a white balance in a conventional television receiver.

In the drawing, reference numeral 10 denotes an image processing unit which performs a series of image processing on the composite image signal CVS. The image processing unit 10 is not shown in the figure, but is provided from a microprocessor as a control unit for controlling the entire apparatus. R (Red) -Y, G (Green) -Y, B (Blue) corresponding to the video signal by processing brightness, tint and color adjustment of the video signal according to the predetermined control signal An image processor outputs a color difference signal such as -Y and a luminance (-Y) signal.

Reference numeral 20 denotes a color signal generator for generating color signals of R, G, and B based on the color difference signal and the luminance signal output from the image processor 10. The color signal generator 20 is configured to generate a color signal from the RY signal. R signal output section 21, G signal output section 22, B signal output section 23 for generating and outputting R signal, G signal from GY signal, and B signal from BY signal, respectively. do.

Here, the R, G, B signal output units 21, 22, and 23 have a bias stage and a drive stage, respectively, and each stage is provided with a rotary switch. By operating this rotary switch, the bias stage adjusts the DC level of the output signals R, G, and B, and the drive stage adjusts the AC level of the output signal.

On the other hand, all the television receivers are provided with a white balance adjusting means for adjusting the light emitting characteristics of the phosphor of the cathode ray tube (CRT) is not uniform, the R, G, B signal output unit 21, 22, 23, the rotary switch of the bias stage and the drive stage is the white balance adjusting means.

If you do not adjust the white balance, the raster will be colored when you change the brightness, the color will come out when you receive monochrome broadcasts, and the color will change when you receive color broadcasts. Immediately after the television receiver is assembled, the light emission characteristics of the R, G, and B phosphors on the CRT are checked using a camera and an RGB level meter, and the RGB level data thus obtained is set in a predetermined memory. Will be adjusted.

However, as described above, the producer manually adjusts the white balance not only increases the adjustment time, but also confirms the human eye to perform the adjustment operation, which makes it very difficult to accurately adjust the white balance. Will be.

Accordingly, the present invention was created in view of the above-described circumstances, and automatically adjusts the white balance in a television receiver which analyzes the level of the RGB color signal generated from the color difference signal and automatically adjusts the white balance based on the analysis result. The object is to provide a device.

1 is a block diagram illustrating a white balance adjustment operation in a conventional television receiver.

Figure 2 is a block diagram showing the configuration of a white balance automatic adjustment device of a television receiver according to an embodiment of the present invention.

* Brief description of the main parts of the drawing

10, 100: image processing unit 20: signal output unit

21, 102: R signal output section 22: G signal output section

23: B signal output unit 101: Timer

103: DC level detector 104: AC level detector

105, 106: A / D converters 107, 108: comparators

109: DC reference level storage unit 110: AC reference level storage unit

111, 112: D / A converter 113: Color difference signal correction

120: processor

In the television receiver according to the present invention for realizing the above object, the apparatus for automatically adjusting white balance includes an image processor for generating and outputting a color difference signal based on a composite video signal, and a color signal for generating and outputting a corresponding color signal based on the color difference signal. A television receiver having an output unit; A reference level data storage unit for storing reference level data of a color signal, a color signal level detector for detecting a level of the color signal from the color signal output from the color signal output unit, and detected by the reference level data and the color signal level detector A comparator for comparing detection levels, an analog signal generator for generating and outputting an analog signal corresponding to the result of the comparator, and synthesizing the color difference signal and a corrected color signal input from the analog signal generator and outputting the synthesized color signal to the color signal output unit. Characterized in that it comprises a color difference signal correction for.

That is, according to the above configuration, it is possible to see a significant gain in terms of time, accuracy, and the like by manually promoting white balance.

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

1 is a block diagram showing the configuration of a white balance automatic adjustment device in a television receiver according to an embodiment of the present invention.

In the drawing, reference numeral 100 denotes an image processor for executing a series of image processing on an image signal, which includes a processor 120 for controlling an operation, reference numeral 101 denotes a timer for counting a predetermined time; 102 denotes an R signal output unit for generating and outputting a predetermined color signal R from the color difference signal RY output from the image processing unit 100.

Further, reference numeral 103 denotes a DC level detector for detecting the DC level from the R signal output from the R signal output unit 102 and outputting the resultant signal. 104 denotes an R output from the R signal output unit 102. AC level detectors 105 and 106 for detecting the AC level from the signal and outputting the resultant signal are A / D converters for converting and outputting analog signals output from the DC or AC level detectors 103 and 104 into digital signals. to be.

Further, reference numerals 107 and 108 denote signals output from the A / D converters 107 and 108 based on predetermined control signals from the microprocessor 12 and reference level storage units 109 and 110 to be described later. D / A converter for comparing the reference level data of the color signals stored in the C) and converting the result into analog signals.

In addition, reference numeral 113 denotes a result signal obtained by synthesizing a signal from the D / A converters 111 and 112 with the color difference signals RY, GY and BY inputted from the processor 120 of the image processor 10. The R signal output unit 102 outputs the signal.

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

First, when a video signal source is input by inputting power to a television receiver, the image processing unit 100 demodulates the color signal C to generate color difference signals R-Y, G-Y, and B-Y.

Subsequently, the generated color difference signal is input to the color difference signal corrector 113 at a later stage, and each of the color difference signals RY, GY, and BY may be R signal output unit 102 or G, B signal output unit ( (Not shown). Then, the R signal output unit 102 generates a color signal R corresponding to the input color difference signal R-Y and outputs it to the CRT. At this time, the DC or AC level signal is detected by the DC level detection unit and the AC level detection units 103 and 104, respectively, and the detected DC or AC level signals are respectively A / D converters 105 and 106. ) Is converted into a digital signal.

At this time, the processor 120 reads the DC or AC reference level data from the DC or AC reference level storage unit 109 or 110, respectively, and then DC or AC of the color signal converted through the A / D converters 105 and 106, respectively. The comparators 107 and 108 are controlled to compare with the level. Thereafter, the comparison values of the comparators 107 and 108 are converted into analog signals and then input to the color difference signal corrector 113. Here, the process of controlling the comparison operation of the comparators 107 and 108 is vacant periodically based on the count value by the timer 101. That is, the processor 120 sets the timer 101 to a predetermined value and then compares the reference level data with the detected data when a predetermined count end signal is input.

Thus, the color difference signal correction unit 113 synthesizes the color difference signal input from the image processing unit 100 and the corrected color signal input from the D / A converters 111 and 112 and then converts the color signal into the R signal output unit 102. By outputting as, the white balance of the output color signal is corrected.

That is, according to the above, the white balance can be automatically adjusted based on the output color signal level, so that a considerable gain can be obtained in terms of time required, accuracy, and the like, which are manually promoted.

In addition, this invention is not limited to the said Example, It can variously deform and implement within the range which does not deviate from the technical summary of this invention.

As described above, according to the present invention, the white balance automatic adjustment device can be realized in a television receiver that can analyze the level of the RGB color signal generated from the color difference signal and automatically adjust the white balance based on the analysis result. .

Claims (1)

A television receiver comprising: an image processing unit for generating and outputting a color difference signal based on a composite video signal; and a color signal output unit generating and outputting a corresponding color signal based on the color difference signal; A reference level data storage unit for storing reference level data of a color signal; A color signal level detector for detecting the level of the color signal from the color signal output from the color signal output unit; A comparator for comparing the reference level data with a detection level detected by the color signal level detector; An analog signal generator for generating and outputting an analog signal corresponding to the result of the comparator; And a color difference signal correction unit configured to synthesize the color difference signal and the corrected color signal input from the analog signal generation unit and output the synthesized color signal to the color signal output unit.