Demura compensation method, device and terminal

Abstract

The present application relates to a demura compensation method, device and terminal, the method comprising: S1, obtaining the compensation grayscale value of the screen; S2, obtaining the high-frequency compensation component and the low-frequency compensation component according to the compensation grayscale value; S3, storing the high-frequency compensation component and the low-frequency compensation component respectively; S4, obtaining the high-frequency compensation grayscale value according to the high-frequency compensation component and obtaining the low-frequency compensation grayscale value according to the low-frequency compensation component; S5, determining the demura compensation value according to the high-frequency compensation grayscale value and the low-frequency compensation grayscale value; S6, applying the demura compensation value to the screen. The scheme of the present application splits the compensation grayscale value into a low-frequency compensation component and a high-frequency compensation component, and stores the low-frequency compensation component and the high-frequency compensation component separately, and independently adjusts the low-frequency compensation component and the high-frequency compensation component by multiplying the frequency, and superimposes the adjusted low-frequency compensation component and the high-frequency compensation component to obtain the demura compensation value of the screen, and the compensation effect is good.

Description

Technical Field

[0001] The present application relates to the technical field of display screens, and in particular to a demura compensation method, device and terminal. Background Art

[0002] The existing Demura technology process is that the CCD camera collects the brightness data of a specific screen, converts the brightness data into the grayscale domain, and then stores and compensates the effect. However, due to the unevenness of the OLED screen, the brightness of the mura area is inconsistent with the brightness of the normal area. Therefore, when adjusting the effect, it is necessary to adjust the data according to the characteristics of the screen itself and use Ratio adjustment. However, due to the human eye's perception of brightness, the human eye is more sensitive to color and brightness changes in large areas. In order to adjust screens with severe uneven brightness and color, a large proportion of compensation value adjustment coefficients will be used. At the same time, the problem is that the compensation value of small Sandy mura is also amplified.

[0003] The current Demura technology has the problem of incompatibility between color unevenness, brightness unevenness and Sandy mura compensation when adjusting the compensation effect: that is, if the color unevenness and brightness unevenness compensation effect is good, additional Sandy mura will be introduced; if the Sandy mura compensation effect is good, the color unevenness and brightness unevenness will be under-compensated.

[0004] In view of the above problems, those skilled in the art have been seeking solutions. Summary of the invention

[0005] The technical problem to be solved by the present application is to provide a demura compensation method, device and terminal in view of the defects of the above-mentioned prior art.

[0006] In order to achieve the above objectives, this application is implemented through the following technical solutions:

[0007] The present application provides a demura compensation method, including:

[0008] S1, obtaining the compensation grayscale value of the screen;

[0009] S2, obtaining a high-frequency compensation component and a low-frequency compensation component according to the compensation grayscale value;

[0010] S3, storing the high-frequency compensation component and the low-frequency compensation component respectively;

[0011] S4, acquiring a high-frequency compensation grayscale value according to the high-frequency compensation component and acquiring a low-frequency compensation grayscale value according to the low-frequency compensation component;

[0012] S5, determining a demura compensation value according to the high-frequency compensation grayscale value and the low-frequency compensation grayscale value;

[0013] S6. Apply the demura compensation value to the screen.

[0014] Optionally, S1 includes:

[0015] Obtain the monochrome brightness values ​​of the three color pixels respectively;

[0016] The monochrome brightness value is converted into a grayscale domain to obtain a compensated grayscale value of a three-color pixel.

[0017] Optionally, S2 includes:

[0018] The compensated grayscale values ​​of the three-color pixels are subjected to frequency domain separation processing respectively to obtain high-frequency compensation components and low-frequency compensation components of the three-color pixels.

[0019] Optionally, S4 includes:

[0020] The high-frequency compensation component and the low-frequency compensation component are subjected to frequency doubling processing respectively to obtain a high-frequency compensation grayscale value and a low-frequency compensation grayscale value.

[0021] Optionally, S5 includes:

[0022] The high-frequency compensation grayscale value and the low-frequency compensation grayscale value of the three-color pixel are superimposed to obtain the Demura compensation value.

[0023] The present application also provides a Demura compensation device, including: a data analysis module, a data storage module, and a data application module;

[0024] The data analysis module is used to obtain the compensation grayscale value of the screen, and obtain the high-frequency compensation component and the low-frequency compensation component according to the compensation grayscale value;

[0025] The data storage module is used to store the high-frequency compensation component and the low-frequency compensation component;

[0026] The data analysis module is further used to obtain a high-frequency compensation grayscale value according to the high-frequency compensation component and a low-frequency compensation grayscale value according to the low-frequency compensation component, and determine a Demura compensation value according to the high-frequency compensation grayscale value and the low-frequency compensation grayscale value;

[0027] The data application module is used to apply the demura compensation value to the screen.

[0028] Optionally, the device further comprises the data acquisition module; the data acquisition module is used to acquire the monochrome brightness value of the three-color pixel;

[0029] The data analysis module is also used to convert the monochrome brightness value into a grayscale domain to obtain a compensated grayscale value of a three-color pixel.

[0030] Optionally, the data analysis module is further used to perform frequency domain separation processing on the compensated grayscale values ​​of the three-color pixels respectively to obtain high-frequency compensation components and low-frequency compensation components of the three-color pixels.

[0031] Optionally, the data analysis module is further used to perform frequency doubling processing on the high-frequency compensation component and the low-frequency compensation component respectively to obtain a high-frequency compensation grayscale value and a low-frequency compensation grayscale value.

[0032] The present application also provides a terminal, comprising: a memory and a processor, wherein a computer program is stored in the memory;

[0033] wherein the processor is configured to execute a computer program in the memory;

[0034] When the computer program is executed by the processor, the above-mentioned Demura compensation method is implemented.

[0035] The present application provides a demura compensation method, device and terminal, which split the compensated grayscale value into a low-frequency compensation component and a high-frequency compensation component, store the low-frequency compensation component and the high-frequency compensation component separately, and independently adjust the low-frequency compensation component and the high-frequency compensation component by multiplying the frequency, and superimpose the adjusted low-frequency compensation component and the high-frequency compensation component to obtain the demura compensation value of the screen, with good compensation effect.

[0036] In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following specifically cites preferred embodiments and describes them in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The present application is described in detail below with reference to the accompanying drawings and specific implementation methods;

[0038] Figure 1 It is a demura compensation system of the prior art.

[0039] Figure 2 It is a flowchart of a Demura compensation method provided in an embodiment of the present application;

[0040] Figure 3 It is a structural schematic diagram of a demura compensation device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0041] It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0042] During the production process of AMOLED displays, due to reasons such as materials and processes, some products may have uneven screen brightness, also known as Mura. This uneven brightness spot mark will cause visual discomfort. Products with this mark cannot meet the specifications of end customers and generally have to be scrapped or downgraded. The external compensation system for the AMOLED production process uses advanced sub-pixel optical imaging technology and software algorithms to eliminate Mura (i.e., Demura, which is equivalent to beautifying the display) from displays with poor Mura, so that the display quality of the display meets the specifications required by the panel factory for shipment and improves the yield rate of mass production of displays.

[0043] Figure 1 It is a demura compensation system of the prior art, please refer to Figure 1 In the prior art, the Demura compensation system includes a CCD camera, a computer, a memory, and a processing IC. The Demura compensation system of an AMOLED display includes the following detailed steps:

[0044] 1. Image acquisition: Light up the AMOLED screen, import different images, use the CCD camera on the compensation device to capture images, and automatically identify the sub-pixel arrangement relationship.

[0045] The images that need to be detected after the panel is turned on are generally different according to the requirements of different panel manufacturers. Common ones include RGB images with 32, 64, 96, 160, 192, and 224 grayscales, a total of 18 images.

[0046] The demura of some panel manufacturers only compensates for brightness differences but not color differences. This type of luminance demura generally only needs to detect grayscale images. In addition, since the mura presented at different grayscales is different, it generally detects the mura of high, medium and low grayscales, and finally averages the demura data. Of course, different panel manufacturers will choose the specific settings according to their actual needs.

[0047] Some panel manufacturers conduct a more comprehensive Color Demura test, which not only compensates for brightness but also chromaticity differences. Some of these types of Color Demura test screens use grayscale screens, while others use RGBW screens. Different panel manufacturers choose different screens based on technology and needs.

[0048] 2. Import the collected images into a high-performance PC (i.e., a computer with the Demura tool software installed on it).

[0049] 3. Use the Demura tool software on the PC to perform data extraction (extracting raw data), compensation (calculating the Mura area, detecting the Mura boundary and generating compensation data), and compression (effectively compressing the generated compensation data for easy storage).

[0050] 4. Save the compressed data in the memory Flash.

[0051] 5. When the Demura function is turned on, data is extracted from the Flash to the SRAM (Static RAM) inside the Driver IC. The IC decompresses the data to obtain complete compensation data, and superimposes the compensation data with the original display data sent from the application end to generate new data that is sent to the Panel for display to confirm the Demura compensation effect.

[0052] The process of online Demura is as follows:

[0053] The calculation process of the mura area generally includes:

[0054] 1. Calculate the average value: Calculate the average value of the data in the table based on the original Demura table;

[0055] 2. Comparison: Compare each data in the original Demura table with the calculated average value;

[0056] 3. Judgment: When the absolute value of the difference between the compared data and the average value is greater than a preset threshold, it is determined that the sub-pixel corresponding to the compared data is included in the Mura area; when the absolute value of the difference between the compared data and the average value is less than or equal to the preset threshold, it is determined that the sub-pixel corresponding to the compared data is not included in the Mura area. The preset threshold can be determined according to the display effect of the display panel.

[0057] The principle of the Demura algorithm can be simply described as: darkening the bright areas, or brightening the dark areas, or eliminating the areas with color cast. The final effect is to make the brightness and color displayed in different areas of the panel roughly the same (pure color picture).

[0058] However, when adjusting the compensation effect, the Demura technology in the prior art often has the problem that the compensation of color unevenness, brightness unevenness and Sandy mura is incompatible: if the compensation effect of color unevenness and brightness unevenness is good, additional Sandy mura will be introduced; if the Sandy mura compensation effect is good, the color unevenness and brightness unevenness will be under-compensated.

[0059] Color unevenness refers to the uneven color on the OLED screen, which is mostly cyan or pink in some areas when displaying a white screen. Brightness unevenness refers to the uneven brightness on the OLED screen, which is mostly brighter or darker in some areas when displaying the same grayscale screen. Sandy mura is a fine granularity on the screen, mostly pixel-level mura. According to the human eye's perception of the uniformity of the OLED screen: color unevenness > brightness unevenness > Sandy mura. Therefore, in order to improve the color and brightness uniformity of the screen, a larger Ratio ratio is often used for effect adjustment, and additional Sandy mura is introduced.

[0060] Based on the above-mentioned prior art, the present application provides a demura compensation method, device and terminal.

[0061] Figure 2 This is a flow chart of a Demura compensation method provided by an embodiment of the present application. Figure 2 , Demura compensation methods include:

[0062] S1. Obtain the compensated grayscale value of the screen.

[0063] Optionally, S1 includes:

[0064] Obtain the monochrome brightness values ​​of the three color pixels respectively;

[0065] The monochrome brightness value is converted to the grayscale domain to obtain the compensated grayscale value of the three-color pixel.

[0066] In one embodiment, the display effect of the OLED screen is composed of R, G, and B sub-pixels, so the monochrome brightness values ​​of R, G, and B are collected during data collection. The brightness values ​​are converted to the grayscale domain to obtain the compensated grayscale values ​​of R, G, and B in the three channels. The compensated grayscale values ​​of the three channels can be used to obtain the compensated values ​​of all sub-pixels on the screen. Therefore, the compensated grayscale values ​​of the three channels of R, G, and B will be processed in steps S2-S5 respectively.

[0067] S2. Obtain a high-frequency compensation component and a low-frequency compensation component according to the compensation grayscale value.

[0068] Optionally, S2 includes:

[0069] The compensation grayscale values ​​of the three-color pixels are subjected to frequency domain separation processing respectively to obtain high-frequency compensation components and low-frequency compensation components of the three-color pixels.

[0070] In one embodiment, the compensation values ​​of the three channels R, G, and B are separated in the frequency domain by using a suitable filtering method, such as mean filtering or filtering by using a filter. Specifically, the low-frequency component in the compensated grayscale value is extracted by using mean filtering, and then the high-frequency component in the compensated grayscale value is obtained by subtracting the original compensated grayscale value from the low-frequency component.

[0071] Color unevenness and brightness unevenness are in the form of gradual changes in compensation data, and are concentrated in the low frequency band in the frequency domain. Sandy mura, on the other hand, is in the form of high-frequency data changes in compensation data, and is concentrated in the high frequency band in the frequency domain. Therefore, by separating low frequency and high frequency and adjusting them separately, the problem of color unevenness, brightness unevenness and Sandy mura compensation being unable to be taken into account at the same time can be effectively avoided.

[0072] S3. Store the high-frequency compensation component and the low-frequency compensation component separately.

[0073] S4. Acquire a high-frequency compensation grayscale value according to the high-frequency compensation component and acquire a low-frequency compensation grayscale value according to the low-frequency compensation component.

[0074] Optionally, S4 includes:

[0075] The high-frequency compensation component and the low-frequency compensation component are frequency-multiplied to obtain a high-frequency compensation grayscale value and a low-frequency compensation grayscale value.

[0076] In one embodiment, when calculating the current picture compensation value, the high-frequency compensation component and the low-frequency compensation component are processed using independent Ratio (ie, frequency multiplication) values.

[0077] S5. Determine a demura compensation value according to the high-frequency compensation grayscale value and the low-frequency compensation grayscale value.

[0078] Optionally, S5 includes:

[0079] The high-frequency compensation grayscale value and the low-frequency compensation grayscale value of the three-color pixel are superimposed to obtain the Demura compensation value.

[0080] In one embodiment, the adjusted high-frequency compensation grayscale value and the low-frequency compensation grayscale value are added to obtain the final output Demura compensation value. Specifically, the calculation of the Demura compensation value can refer to the following formula:

[0081] outcomp=compHigh1+compLow1=compHigh*Ratio1+compLow*Ratio2

[0082] Among them, outcomp is the Demura compensation value, compHigh is the high-frequency compensation component obtained by filtering, compHigh1 is the high-frequency compensation grayscale value after frequency doubling processing, compLow is the low-frequency compensation component obtained by filtering, compLow1 is the low-frequency compensation grayscale value after frequency doubling processing, Ratio1 is the high-frequency multiplication value, and Ratio2 is the low-frequency multiplication value.

[0083] Based on the data processing of steps S2-S5, the demura compensation values ​​of the three channels R, G, and B can be obtained. The demura compensation values ​​of the three channels R, G, and B are added together to obtain the demura compensation values ​​of all sub-pixels on the screen. In step S6, the compensation value is applied to the screen to perform demura compensation on the screen.

[0084] S6. Apply the demura compensation value to the screen.

[0085] In one embodiment, the present application can also place the step of separating the high-frequency compensation component from the low-frequency compensation component after storing in the memory and before calculating the display screen compensation value, and the same Demura compensation effect can be achieved. However, this will cause the frequency domain separation step to be processed by the processing IC, consuming the processing IC computing power. The frequency domain separation step of this solution is processed by the PC and does not consume the Driver IC computing power.

[0086] The technical solution of the present application splits the compensated grayscale value into a low-frequency compensation component and a high-frequency compensation component, stores the low-frequency compensation component and the high-frequency compensation component separately, and independently adjusts the low-frequency compensation component and the high-frequency compensation component by multiplying the frequency, and superimposes the adjusted low-frequency compensation component and the high-frequency compensation component to obtain the demura compensation value of the screen; the problem that demura compensation cannot take into account color unevenness, brightness unevenness compensation and Sandy mura compensation at the same time can be solved, and at the same time, the taste effect of the OLED screen can be improved, and the yield rate can be improved.

[0087] Figure 3 This is a schematic diagram of the structure of a Demura compensation device provided in an embodiment of the present application. Figure 3 The present application also provides a Demura compensation device, including: a data analysis module 10, a data storage module 20, and a data application module 30.

[0088] The data analysis module 10 is used to obtain the compensated grayscale value of the screen, and obtain the high-frequency compensation component and the low-frequency compensation component according to the compensated grayscale value.

[0089] The data storage module 20 is used to store high frequency compensation components and low frequency compensation components. In one embodiment, the data storage module 20 includes a high frequency storage module and a low frequency storage module, which are used to store high frequency compensation components and low frequency compensation components respectively to avoid frequency mixing.

[0090] The data analysis module 10 is further used to obtain a high-frequency compensation grayscale value according to the high-frequency compensation component and a low-frequency compensation grayscale value according to the low-frequency compensation component, and determine a demura compensation value according to the high-frequency compensation grayscale value and the low-frequency compensation grayscale value.

[0091] The data application module 30 is used to apply the demura compensation value to the screen.

[0092] Optionally, the device also includes a data acquisition module (not shown in the figure); the data acquisition module is used to acquire the monochrome brightness values ​​of the three-color pixels; in one embodiment, in one embodiment, the display effect of the OLED screen is composed of R, G, and B sub-pixels, and the data acquisition module acquires the monochrome brightness values ​​of R, G, and B.

[0093] The data analysis module 10 is further configured to convert the monochrome brightness value into a grayscale domain to obtain compensated grayscale values ​​of the three-color pixels.

[0094] Optionally, the data analysis module 10 is further configured to perform frequency domain separation processing on the compensated grayscale values ​​of the three-color pixels respectively to obtain high-frequency compensation components and low-frequency compensation components of the three-color pixels.

[0095] Optionally, the data analysis module 10 is further configured to perform frequency doubling processing on the high-frequency compensation component and the low-frequency compensation component respectively to obtain a high-frequency compensation grayscale value and a low-frequency compensation grayscale value.

[0096] The present application also provides a terminal, comprising: a memory and a processor, wherein a computer program is stored in the memory;

[0097] wherein the processor is configured to execute a computer program in the memory;

[0098] When the computer program is executed by a processor, the above-mentioned Demura compensation method is implemented.

[0099] The technical solution of the present application is to split the compensation grayscale value into a low-frequency compensation component and a high-frequency compensation component, store the low-frequency compensation component and the high-frequency compensation component separately, and independently adjust the low-frequency compensation component and the high-frequency compensation component by frequency doubling, and superimpose the adjusted low-frequency compensation component and the high-frequency compensation component to obtain the demura compensation value of the screen; it can solve the problem that demura compensation cannot take into account color unevenness, brightness unevenness compensation and Sandy mura compensation at the same time, and at the same time can improve the taste effect of the OLED screen and improve the yield. Furthermore, this solution: Compared with the compensation method of the prior art, the present invention has a better compensation effect for Sandy mura while satisfying the color unevenness and brightness unevenness compensation effects.

[0100] Obviously, those skilled in the art can make various changes and modifications to the invention without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these changes and variations. The technical features of the above-described embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0101] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A demura compensation method, characterized in that: Applied to OLED screens, including: S1, obtaining the compensation grayscale value of the screen; S2, obtaining a high-frequency compensation component and a low-frequency compensation component according to the compensation grayscale value; S3, storing the high frequency compensation component and the low frequency compensation component respectively; S4, acquiring a high-frequency compensation grayscale value according to the high-frequency compensation component and acquiring a low-frequency compensation grayscale value according to the low-frequency compensation component; S5, determining a demura compensation value according to the high-frequency compensation grayscale value and the low-frequency compensation grayscale value; S6, applying the Demura compensation value to the screen; S1 includes: Obtain the monochrome brightness values ​​of the three color pixels respectively; Converting the monochrome brightness value into a grayscale domain to obtain compensated grayscale values ​​of three-color pixels; S2 includes: Performing frequency domain separation processing on the compensated grayscale values ​​of the three-color pixels respectively to obtain high-frequency compensation components and low-frequency compensation components of the three-color pixels; S4 includes: Performing frequency doubling processing on the high-frequency compensation component and the low-frequency compensation component respectively to obtain a high-frequency compensation grayscale value and a low-frequency compensation grayscale value; S5 includes: Superimposing the high-frequency compensation grayscale value and the low-frequency compensation grayscale value of the three-color pixel to obtain the Demura compensation value; The calculation formula of the Demura compensation value is: outcomp=compHigh1+compLow1=compHigh*Ratio1+compLow*Ratio2; Among them, outcomp is the Demura compensation value, compHigh is the high-frequency compensation component, compHigh1 is the high-frequency compensation grayscale value, compLow is the low-frequency compensation component, compLow1 is the low-frequency compensation grayscale value, Ratio1 is the high-frequency multiplication value, and Ratio2 is the low-frequency multiplication value.

2. A Demura compensation device based on the method of claim 1, characterized in that: Applied to OLED screens, including: data analysis module, data storage module, data application module; The data analysis module is used to obtain the compensation grayscale value of the screen, and obtain the high-frequency compensation component and the low-frequency compensation component according to the compensation grayscale value; The data storage module is used to store the high-frequency compensation component and the low-frequency compensation component; The data analysis module is further used to obtain a high-frequency compensation grayscale value according to the high-frequency compensation component and a low-frequency compensation grayscale value according to the low-frequency compensation component, and determine a Demura compensation value according to the high-frequency compensation grayscale value and the low-frequency compensation grayscale value; The data application module is used to apply the Demura compensation value to the screen; The device also includes a data acquisition module; the data acquisition module is used to acquire the monochrome brightness value of the three-color pixels; The data analysis module is also used to convert the monochrome brightness value into a grayscale domain to obtain a compensated grayscale value of a three-color pixel; The data analysis module is also used to perform frequency domain separation processing on the compensated grayscale values ​​of the three-color pixels to obtain high-frequency compensation components and low-frequency compensation components of the three-color pixels; The data analysis module is also used to perform frequency doubling processing on the high-frequency compensation component and the low-frequency compensation component to obtain a high-frequency compensation grayscale value and a low-frequency compensation grayscale value; The calculation formula of the Demura compensation value is: outcomp=compHigh1+compLow1=compHigh*Ratio1+compLow*Ratio2; Among them, outcomp is the Demura compensation value, compHigh is the high-frequency compensation component, compHigh1 is the high-frequency compensation grayscale value, compLow is the low-frequency compensation component, compLow1 is the low-frequency compensation grayscale value, Ratio1 is the high-frequency multiplication value, and Ratio2 is the low-frequency multiplication value.

3. A terminal, characterized in that: include: A memory and a processor, wherein the memory stores a computer program; wherein the processor is configured to execute a computer program in the memory; When the computer program is executed by the processor, the demura compensation method according to claim 1 is implemented.

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