KR0176832B1 - Color information loss compensating method and apparatus of television - Google Patents

Abstract

The present invention relates to a method and apparatus for compensating for color information loss of a TV system. In the related art, since an optical sensor operates sensitively only at a light of a specific frequency, it does not smoothly cope with all of the surrounding light, that is, light by incandescent and fluorescent lights. There is a problem that the brightness of the light is different depending on the ambient light, and there is also a problem that does not sufficiently compensate for the loss of color information due to the external panels by controlling the contrast and brightness of the screen. In order to solve this problem, the present invention has been made to detect the brightness and type of ambient light and to correct the contrast, brightness, color density, sharpness, and contour accordingly, as well as to correct the white balance according to the corrected contrast. According to the present invention, an optimum image can be displayed by compensating for loss of color information caused by an external font by controlling a contrast, brightness, color density, sharpness, and contour correction white balance by applying a sensor that can accommodate a full-wave of ambient light. .

Description

Color information loss compensation method and apparatus of TV system

1 is a block diagram of a conventional image processing apparatus.

2 is a characteristic diagram of a brightness detector of FIG.

3 is a block diagram of a color information loss compensation device of the present invention.

4 is a characteristic diagram of an ambient light detector in FIG. 3;

5 is a signal flow diagram for color information loss compensation of the present invention.

6 (a) to (c) are tables of correction data in the present invention.

7 is a signal flow diagram for detecting ambient brightness in FIG.

8 is a signal flow diagram for data correction according to ambient brightness in FIG.

9 is a signal flow diagram showing a practical example of FIG.

FIG. 10 is a table showing correction data in FIG.

11 is a signal flow diagram for white balance correction in FIG.

12 is a signal flow diagram for contour correction in FIG.

* Explanation of symbols for main parts of the drawings

201: ambient light detector 202: microcomputer

203: Image processing unit 204: Monitor (CPT)

205: key matrix 211: RGB sensor

212: signal amplifier 213: analog / digital converter

The present invention relates to compensation for color information loss. In particular, in order to prevent loss of color information by changing the color generated from the monitor to color information that is difficult to see by an external light source, ambient light is detected when color output is detected. The present invention relates to a method and apparatus for compensating for color loss of a TV system to compensate for the loss of color information caused by the same.

FIG. 1 is a block diagram of a conventional image processing apparatus. As shown therein, a chroma unit for displaying an image on a screen by processing an input image signal and outputting a color difference signal RY, GY, BY to the monitor 104 And a brightness detector 101 for sensing the amount of light around the monitor 104 and information of the brightness detector 101 to control the contrast and brightness of the chroma unit 103. The microcomputer 102 to control and the key matrix 105 connected to this microcomputer 102 and selecting a key for a function setting are comprised.

The brightness detector 101 generally uses an optical sensor called a CDS.

The photoelectric sensor (CDS) outputs a voltage by changing the anode resistance of the sensor according to the brightness of the surroundings. The sensing characteristics are sensitive to light having a wavelength of about 480 nm and a wavelength of 650 nm as shown in FIG. There is something that works sensitively.

Referring to the operation of the conventional device as follows.

First, an image is displayed on the screen as the chroma unit 103 processes the image input signal and inputs the color difference signals R-Y, G-Y, and B-Y to the monitor 104.

At this time, the brightness sensor 101 detects the ambient brightness of the monitor 104 by the external light source by the optical sensor CDS and outputs the brightness information to the microcomputer 102. The optical sensor CDS is detected. The anode resistance changes according to one brightness, and the brightness information is output as a voltage.

Accordingly, the microcomputer 102 controls the brightness and brightness of the color difference signals R-Y, G-Y, and B-Y by controlling the chroma unit 103 to adjust the brightness of the screen of the monitor 104 according to the ambient brightness.

That is, when the surroundings are bright, the screen of the monitor 104 is also brightened proportionally.

However, in the related art, since the optical sensor operates sensitively only at light of a specific frequency, as shown in the sensing characteristic curve of FIG. 2, the brightness of the screen is reduced because it does not cope with all ambient light, that is, light by incandescent and fluorescent lamps. There was a problem that a difference occurs depending on the light.

In addition, there is a problem in that conventionally, only the brightness and brightness of the screen are controlled to sufficiently compensate for the loss of color information due to ambient external light.

Accordingly, the present invention detects the brightness and type of the ambient light in order to improve the conventional problems, and corrects the contrast, brightness, color density, sharpness and contour accordingly, and also corrects the white balance according to the corrected contrast. An object of the present invention is to provide a method and apparatus for compensating for loss of color information of a TV system, which is capable of displaying an image.

In order to achieve the above object, the present invention includes the steps of detecting color information in ambient light, determining the ambient brightness corresponding to the sum of the detected values, and setting the contrast, brightness, color density and sharpness, Setting the contour correction data in association with the contrast value set in the step; setting the correction value of the white balance according to the brightness of the surroundings corresponding to the sum of the detected values; and losing the color information with the setting data. Perform the steps to calibrate.

The color information detecting step includes detecting and storing color information R, G, and B in ambient light, applying the detected color information at an arbitrary ratio, and applying existing cumulative color information at an arbitrary ratio. And adding the stored values, and storing the added values.

The setting of the contrast, brightness, color intensity, and sharpness may include calculating the ambient brightness as the sum of the RGB sensors so that the RGB sensor values may be summed to recognize all the bands of general light, and the sum data calculated above may be randomized. It is stored in a register and an index register is set to 0 to compare the value of the comparison table with the value of the any register so that the value of the register is greater than the value of the comparison table or the index value is greater than the total length of the table. If it is large, the index value is recognized as ambient brightness information, and each image data is set by referring to values of contrast, brightness, color density, and freshness in the image data table for each case of ambient brightness.

The white balance setting step may include a wave wave for determining an ambient brightness, controlling 13000 ° K if the ambient brightness is greater than or equal to the maximum setting brightness, and controlling 9000 ° K if the ambient brightness is less than the minimum setting brightness. If the B color information is equal to or greater than the R color information, the process of controlling the color temperature to 12000 ° K, and if the ambient brightness is determined to be between the maximum and minimum set brightness, the R color information is determined. Determining the difference between the R color information and the B color information if it is larger than the B color information; and if the difference value is equal to or greater than an arbitrary reference value, the color temperature is controlled to 10000 ° K and 11000 if the difference value is smaller than the arbitrary reference value. The process of controlling the color temperature with ° K is carried out.

The present invention also provides an image processing means for converting an image input signal into a color difference signal by correcting contrast, brightness, outline correction, and the like, and controlling the color difference signal to be deflected and output to the display means. Ambient light detection means for detecting and digitally converting a specific color component by an RGB sensor, and receiving the color information of the ambient light detection means to control the contrast, brightness, sharpness, contour correction and white balance adjustment operations of the image processing means. Control means and key matrix means for inputting a setting mode to the control means.

The RGB sensor can accommodate most of the wavelength range of visible light.

Hereinafter, the present invention will be described in detail with reference to the drawings.

3 is a block diagram of an apparatus of the present invention, as shown therein, converts an image input signal into color difference signals RY, GY, BY by correcting contrast, brightness, outline correction, and the like, and converts the color difference signals RY, GY, The image processing unit 203 which deflects BY) and outputs it to the monitor 204, the ambient light detector 201 which detects and digitally converts specific colors R, G, and B from ambient light, and the ambient light detector Micro computer 202 for controlling the contrast, brightness, sharpness, outline correction, and white balance adjustment operation of the image processor 203 by inputting color information of 201, and inputting a setting mode to the micro computer 202. A key matrix 205 is provided.

The ambient light detector 201 includes an RGB sensor 211 for detecting a specific color R, G, and B from ambient light, and a signal amplifier 212-1 to a predetermined level amplified output of the RGB sensor 211. 212-3 and analog / digital converters 213-1 to 213-3 for digitally converting the outputs of the signal amplifiers 212-1 to 212-3.

As shown in FIG. 4, the RGB sensor 211 operates most sensitively at a wavelength of 600 nm for the R sensor, 540 nm for the G sensor, and 480 nm for the B sensor, thereby synthesizing all the detected colors (R, G, B). In other words, it is possible to accommodate most of the wavelength range of visible light, which is about 400 to 700 nm.

Referring to the operation and effect of the present invention configured as described above are as follows.

The image processor 203 adjusts the contrast, brightness, color density, sharpness, outline correction, and white balance of the image input signal and converts the color difference signal (RY, GY, BY) into the color difference signal (RY, GY, BY). ) Is deflected and output to the monitor 204 to display an image.

At this time, when the ambient light detector 201 detects a specific color (R, G, B) with respect to the natural light around the monitor 204 by the RGB sensor 211, a predetermined level in the signal amplifiers 212-1 to 212-3. This amplified signal is digitally converted by the analog / digital converters 213-1 to 213-3, and then output to the microcomputer 202.

Accordingly, the microcomputer 202 detects the output of the ambient light detector 201 and compensates for the loss of color information caused by the ambient light as shown in FIG. 5.

That is, the microcomputer 202 periodically searches the output value of the ambient light detector 201, reads specific color information detected by the RGB sensor 211 (51), and then controls the contrast of the image processor 203 according to the value. Then, the brightness, color intensity and sharpness adjustment values are set (52), the contour correction data is set according to the set contrast adjustment values (53), and the white balance adjustment values are set according to the detected specific color information (S4). .

Thereafter, the microcomputer 202 outputs the setting values for adjusting the contrast, brightness, color intensity, and sharpness, the contour correction data, and the white balance adjustment value to the image processing unit 203 (S5) to provide color information for the image input signal. By compensating for the loss, an optimal image is displayed on the screen of the monitor 204.

In other words, the microcomputer 202 outputs the contrast, brightness, color density, sharpness, outline correction, and white balance values set by the RGB sensor 211 to the image processor 203 to compensate for the lost color information. do.

Referring to the above operation in detail as follows.

First, the operation of the microcomputer 202 to read the detection value of the RGB sensor 211 is as shown in FIG.

The microcomputer 202 reads the quantized values from the analog / digital converters 213-1 to 213-3 by searching for the output of the ambient light detector 201 and stores the respective R, G, B detected values in an arbitrary memory. And store 25% of the R, G, and B detected values to 75% of the existing stored values, and store the summed value in new RAM (r-RAM1 to r-RAM3). do.

For example, the R detection values reflect 75% of the previously accumulated value and add up to reflect 25% of the new value to reduce the degree of error if the detection value is read incorrectly.

The operation of the microcomputer 202 to set the adjustment values of the brightness, brightness, color density, and sharpness of the surrounding brightness, that is, by detecting specific color information is as shown in FIG.

The microcomputer 202 determines the amount of light Lux input to the RGB sensor 211 based on the detection value of the ambient light detector 201, that is, the ambient brightness, and determines the contrast, brightness, and color according to the corresponding brightness. After setting the density and sharpness, the color is set to 50%.

When the amount of light (Lux) input to the RGB sensor 211 is divided into seven sections of 0 to 10, 10 to 30, 30 to 50, 50 to 70, 70 to 85, 85 to 100, and 100 LUX or more, incident light amount Contrast, brightness, color intensity and sharpness according to Lux are set as shown in FIG.

For example, if the ambient brightness is in the range of 10-30 LUX, the microcomputer 202 sets the adjustment value to 40% of the contrast, 42% of the brightness, 41% of the color density, and 33% of the sharpness.

Fig. 9 shows a practical example of the operation of setting the adjustment values of the contrast, brightness, color density and sharpness based on the table of Fig. 6 (a).

Here, the table for detecting the ambient brightness in FIG. 6 (a) is the same as in FIG. 10 (a), and the table corresponding to the contrast, brightness, color intensity, and sharpness for each ambient brightness is shown in FIG. The table of FIG. 10 (a) shows the amount of light input to the RGB sensor 21 with respect to the sum (R + G + B) of specific color information in units of 5LUX, and FIG. 10 (b). ) Lists the contrast, brightness, color intensity, and sharpness data for the ambient brightness divided by SLUX units.

First, the microcomputer 202 is a sum (R + G + B) of the color information R, G, and B detected by the RGB sensor 211 of the ambient light detector 201, that is, r-Rdata + r-Gdata + After storing r-Bdata in the A register (S300), the X register for indexing the X-th address of the table of FIG. 10 (a) to 0 is determined by the output of the sensor 211. After clearing (5301) sequentially increasing the value of x by 1 until the stored value of the A register becomes larger than the value of any x-th address in the table of FIG. 10 (a) stored in the X register. Comparison is made (S302, S303, S304).

The reason why the sum of the color information (R + G + B) is used is that when the wavelength range of the general light is 400-700 nm, the sum of the R, G, and B sensors 211-1 to 211-3 is the wavelength of the general light. You want to accommodate the range so that you can accurately recognize the ambient brightness.

At this time, the sequential comparison operation causes the stored value of the A register to become larger than the value of the x-th address in the table of FIG. 10 (a) (S302), or the value of the x-th address increased by 1 (TVC-ADrefE-TVC). If larger than (ADref) (S304), the microcomputer 202 recognizes the value of x as the value of the ambient brightness.

The process (S304) is for recognizing the end of the comparison data, grasping the total number of data tables, comparing the total number of tables of the data, and ending. The step (S304) increases with the difference value of the address (TVC-ADrefE-TVC-ABref). The number of comparisons with the value of the registered x register, that is, the limit of the value of the x register.

Therefore, when recognizing the x value corresponding to the ambient brightness, the microcomputer 202 is configured as shown in FIG. 10 (b) by pairing four data of contrast, brightness, color intensity, and sharpness for each ambient brightness. It is stored 4 times as the value of x. (S305)

Thereafter, the microcomputer 202 contrasts the x-th data, the (x + 1) -th data, the (x + 2) -th data, and the color concentration from the x-th filter of FIG. , the (x + 3) th data is set to the adjustment value of the sharpness (S306 to S309) and the color value is set to 50%.

In addition, when the adjustment values of contrast, brightness, color density and sharpness are set, the contour correction data is set to the set contrast values, which are the same as those of FIG. 12 to distinguish the boundary between one object and another on the screen. .

First, the microcomputer 202 stores the contrast value set by the output of the ambient light detector 201 in the A register, and then determines the range to which the contrast value belongs.

Accordingly, the contour correction data according to the contrast value is the same as the table of FIG. 6C. The microcomputer 202 has corresponding contour correction data for proportionally controlling the speed of the electron beam according to the contrast value stored in the A register. Will be set.

In other words, the microcomputer 202 has 3 (S501, S502) when the contrast value is 91-100%, 2 (S503, S504) when 61-90%, 1 (S505, S506) when 31-60%, The contour correction data is set to be 0 (S507, S508) at 0-30%.

On the other hand, when the setting of the contour correction data is completed as described above, in adjusting the white balance so that all the colors on the screen have a continuous correlation, the microcomputer 202 is white according to the output value of the ambient light detector 201. The adjustment value of the balance is set by the same operation as shown in the signal flow chart in FIG. 11. The adjustment value of the white balance is controlled according to the ambient brightness and the spectrum of the ambient light (color of light), and the color temperature of the screen The degree to which the value is felt is expressed in absolute temperature.

Here, the white balance is adjusted by the gain of R fixed to an arbitrary value and the gain of variable G and B. The color temperature is divided into 13000 ° K and 9000 ° K when adjusted by the ambient brightness, and the color of the ambient light (spectrum ), It is divided into 10000 ° K, 11000 ° K, and 12000 ° K. The color coordinates at the color temperature (13000 ° K) are set to X = 266 and Y = 280.

The white balance data is divided into a low light and a high light, and the portions of the low light are G-cutoff data (G-CUT) and B-cutoff data (B-CUT). The parts of the light are G-AMP and B-AMP.

Data for such white balance correction is shown in the table of FIG.

First, the microcomputer 202 stores the value (R + G + B) detected by the RGB sensor 211 in the A register in order to adjust the white balance (S400), and determines the range to which the stored value belongs to A If the stored value of the register is 46 or more, that is, 100Lux or more, it is controlled by the color temperature (13000 ° K), and the white balance correction data is set to 0 for G-CUT, B-CUT, G-AMP, and B-AMP, respectively (S401, S402). 3, that is, less than 10Lux, it is controlled by color temperature (9000 ° K) so that G-CUT is G-CUT-1, B-CUT is B-CUT-2, G-AMP is G-AMP-4, B- AMP is set to B-AMP-12 (S403, S404).

When the stored value of the 4 register is between 100Lux and 10Lux (A46, A≥3), the artificial light determines whether the artificial light is incandescent or fluorescent based on the spectrum of ambient light.

At this time, if the B sensor value is larger than the R sensor value (r-Bdata ≥ r-Rdata), that is, if the fluorescent component is controlled by the color temperature (12000 ° K), the G-CUT is G-CUT-1, and the B-CUT is B- Set CUT-1 and G-AMP to G-AMP and B-AMP to B-AMP-2.

On the contrary, if the R sensor value is larger than the B sensor value, the difference between the R sensor value and the B sensor value is stored in the A register, and then it is determined whether the stored value is equal to or greater than 20 Lux.

At this time, if the stored value of 4 register is equal to or greater than 20 Lux, it is controlled by color temperature (10000 ° K) so that G-CUT is G-CUT-1, B-CUT is B-CUT-2, and G-AMP is G. -Set AMP-3 and B-AMP to B-AMP-8, and if the stored value of A register is less than 20 Lux, it is controlled by color temperature (11000 ° K) and G-CUT is G-CUT-1, B- CUT is set to B-CUT-1, G-AMP to G-AMP-1, and B-AMP to B-AMP-5.

That is, if the value of the R sensor is much larger than the value of the B sensor, the color temperature is controlled to 10000 ° K. If the value is small (r-Rdata-r-Bdata 5), the color temperature is controlled to 11000 ° K.

For example, if the color temperature is set to 10000 ° K, the white balance data is subtracted from the factory-set G-CUT data at 13000 ° K and 2 is subtracted from the B-CUT data. 4 is subtracted and 12 is subtracted from the B-AMP data.

When the above operation is terminated, the microcomputer 202 outputs the correction data of the contrast, brightness, color density, sharpness and white balance to the image processor 203 so that the image processor 203 controls the contrast of the image input signal. , Brightness, color density, etc. are controlled to display an optimal image on the monitor 204.

As described in detail above, the present invention is optimized by compensating for the loss of color information caused by external light by controlling all the contrast, brightness, color density, sharpness, and contour correction white balance by applying a sensor that can accommodate the electric field of ambient light. There is an effect that can display the video.

Claims (8)

A first step of detecting color information in ambient light, a second step of setting contrast, brightness, color intensity and sharpness by judging the ambient brightness corresponding to the sum of the detected values from a predetermined table, and A third step of setting the contour correction data in association with the set contrast value, and setting a correction value of the white balance by comparing the ambient brightness corresponding to the sum of the detected values with the preset maximum and minimum brightness values; And a fifth step of correcting color information loss using the setting data. The method of claim 1, wherein the first step includes detecting and storing color information R, G, and B in ambient light, and applying the detected color information in an arbitrary ratio, and accumulating existing color information. And a third process of applying and applying the sum at an arbitrary ratio and a third process of storing the summed values. The method of claim 1. The second step is a first process of storing the sum of the R, G, B sensed values and then comparing the values of the comparison table stored in an arbitrary index register, and if the sum is less than the value of the comparison table, And a second step of comparing the total length of the index with the index value, and if the sum is greater than the value of the comparison table or the index value is greater than the total length of the comparison table, the index value is recognized as the peripheral brightness information and the contrast is contrasted in the data table. And performing a third process of setting corresponding data of brightness, color density, and clarity. The method of claim 1, wherein the fourth step sets the color temperature to 13000 ° K or 9000 ° K according to the ambient brightness, and sets one of 10000 ° K, 11000 ° K, and 12000 ° K according to the color of the ambient light. Color information loss compensation method of the TV system, characterized in that. 5. The method of claim 4, further comprising: a first process of determining the ambient brightness, a second process of controlling the temperature at 13000 ° K if the ambient brightness is greater than or equal to the maximum setting brightness and 9000 ° K if the ambient brightness is less than the minimum setting brightness; If the ambient brightness is determined to be between the maximum and minimum set brightness, the third process of controlling the color temperature to 12000 ° K when the B color information is equal to or greater than the R color information, and the ambient brightness is determined between the maximum and minimum set brightness. If the R color information is greater than the B color information, the third step of determining the difference between the R color information and the B color information, and if the difference value is greater than or equal to any reference value, the color temperature is controlled to 10000 ° K and the difference value And a fourth process of controlling the color temperature to 11000 ° K when the reference value is smaller than the predetermined reference value. Image processing means for converting an image input signal into a color difference signal by correcting contrast, brightness, and contour correction, deflecting the color difference signal and outputting it to a display means, and digitally converting a specific color component from ambient light with an RGB sensor. When the ambient light detection means and color information are detected by the ambient light detection means, the previous detection value is summed at an arbitrary ratio, and the sum value is compared with a preset table value to compare the brightness, brightness, sharpness, and outline of the image processing means. And control means for controlling correction and white balance adjustment operations, and key matrix means for inputting a setting mode to the control means. The method according to claim 6, wherein the ambient light detecting means comprises: R, G, B sensors for detecting specific color information of ambient light, and first to third signal amplifiers each amplifying a predetermined level of the output of the R, G, B sensors. And first to third analog / digital converters for digitally converting the outputs of the first to third signal amplifiers and outputting them to the control means. The apparatus of claim 7, wherein the R, G, and B sensors have a sum of specific color signals that can accommodate most of a wavelength range of visible light.