Pixel point luminance compensation method and device

Abstract

This application provides a pixel point luminance compensation method and device, which includes N calculation steps (N≧2), each calculation step including: obtaining an image displayed on a display screen with different grayscale signals, extracting the luminance of each pixel point at different grayscale signals from the image; determining a reference pixel point, calculating difference parameters of the luminance of each pixel point at different grayscale signals relative to the reference pixel point; fitting the difference parameters of each pixel point to the initial luminance of the corresponding pixel point at different grayscale signals to obtain an initial luminance-difference parameter curve; and calculating compensation parameters for each pixel point, where i=2 to N in the i-th calculation step, and the image displayed on the display screen with different grayscale signals is obtained by compensating the initial luminance of each pixel point at different grayscale signals according to the compensation parameters obtained in the i-1th calculation step.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority from Chinese Patent Application No. 201810654951.9, filed on June 22, 2018, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to the field of display technology, and in particular to a pixel point luminance compensation method and apparatus. [Background technology]

[0003] OLED (Organic Light-Emitting Diode) display devices are said to be the most promising display devices because they have features such as self-luminance, high brightness, high contrast, low operating voltage, and the ability to fabricate flexible display devices.

[0004] In the conventional OLED display screen production process, it is difficult to guarantee the brightness uniformity of the entire screen, which affects the production yield. Optical compensation can effectively improve the brightness uniformity of each pixel point of the display screen, and improve the product yield and quality. The general process of optical compensation is to use CCD (Charge Coupled Device) to extract the brightness or contrast of the pixel points of the entire screen, find the brightness difference between each pixel point and the reference pixel point through calculation, and then perform corresponding compensation for each pixel point, which is expected to display almost the same brightness on the pixel points of the entire screen. Summary of the Invention [Means for solving the problem]

[0005] In one aspect, the disclosed embodiment comprises: It includes N calculation steps, where N>=2. The calculation process for each round is as follows: Sequentially inputting different grayscale signals to a display screen, acquiring an image displayed by the display screen with the different grayscale signals, and extracting luminance of each pixel point with the different grayscale signals from the image; determining a reference pixel point from each of the pixel points; and calculating a difference parameter of the luminance of each pixel point in different grayscale signals relative to the luminance of the corresponding grayscale signal of the reference pixel point; fitting the difference parameter of each pixel point to the initial brightness of the corresponding pixel point in different grayscale signals to obtain an initial brightness-difference parameter curve of each pixel point; calculating compensation parameters for each pixel point based on the initial luminance-difference parameter curve for each pixel point; The initial luminance is the luminance of each pixel point at different grayscale signals obtained in the first calculation process, and in the i-th calculation process, i=2 to N, the image displayed on the display screen at different grayscale signals is an image obtained by compensating the initial luminance of each pixel point at different grayscale signals according to the compensation parameter obtained in the (i-1)th calculation process. A pixel point luminance compensation method is provided.

[0006] In some embodiments, the step of calculating a difference parameter of a luminance in a different grayscale signal of each pixel point relative to a luminance in a corresponding grayscale signal of the reference pixel point comprises: The number of grayscale signals input sequentially to the display screen in each calculation process is M (M≧2), and the number of pixels included in the display screen is D; Calculating a difference parameter for each pixel point according to the following formula (1):

[0007]

number

[0008] Among them, j = 1 to M, x = 1 to D, and L r jis the luminance of the j-th grayscale signal of the reference pixel point, L x,j is the luminance of the j-th grayscale signal at the x-th pixel point, Q x,j is a difference parameter of the luminance of the j-th grayscale signal of the x-th pixel point relative to the luminance of the j-th grayscale signal of the reference pixel point.

[0009] In some embodiments, the fitting performed in the step of fitting the difference parameters of each pixel point to the initial luminance of the corresponding pixel point in different grayscale signals is a linear function fitting; Calculating compensation parameters for each pixel point according to the initial brightness-difference parameter curve for each pixel point includes: expressing an initial brightness-difference parameter curve for each pixel point using the following formula (2);

[0010]

number

[0011] (Of these, Q x is the difference parameter of the luminance of the grayscale signal of the x-th pixel point from the luminance of the corresponding grayscale signal of the reference pixel point, L 0 x is the initial luminance of the corresponding grayscale signal of the xth pixel point, K' x , K.” x is the coefficient), K' x , K.” x Calculate the value of K' x Let K” be the first compensation parameter of the x-th pixel point. x a step of setting the second compensation parameter of the x-th pixel point as Includes.

[0012] In some embodiments, the step of compensating for the initial luminance of the different grayscale signals of each pixel point comprises: Calculating the compensation luminance at different gray scale signals of each pixel point according to the following formula (3);

[0013]

number

[0014] (Of these, L x,j is the compensation luminance of the jth grayscale signal at the xth pixel point, L 0 x,j is the initial luminance of the jth grayscale signal at the xth pixel point, K' x , K.” x is the compensation parameter obtained in the (i-1)th calculation process), Obtaining a compensation grayscale signal corresponding to the compensation brightness in different grayscale signals of each pixel point according to the corresponding relationship between the grayscale signal and the brightness; When different gray scale signals are sequentially input to a display screen, for each pixel point, the input different gray scale signals are converted into corresponding compensation gray scale signals, so that each pixel point displays a corresponding compensation luminance; Includes.

[0015] In some embodiments, the compensation method comprises: During the process of actually displaying the image on the display screen, Obtaining uncompensated luminance corresponding to each pixel point in an image to be displayed by a display screen; Reading out the compensation parameters obtained in the Nth calculation process; Calculating the compensated luminance after compensation for each pixel point according to the following formula (4);

[0016]

number

[0017] (Of these, L xis the compensation luminance for the x-th pixel point, L 0 x is the uncompensated luminance of the xth pixel point, K' x,N is the first compensation parameter of the x-th pixel point to be compensated obtained in the Nth calculation process, K x,N is the second compensation parameter of the x-th pixel point to be compensated in the N-th calculation process), obtaining a compensation grayscale signal corresponding to the compensation luminance of each pixel point from the corresponding relationship between the grayscale signal and the luminance; inputting a corresponding compensation grayscale signal to each pixel point to display a corresponding compensation luminance at each pixel point; Further includes:

[0018] In some embodiments, the compensation method further includes the step of: after each calculation process is completed and the compensation parameters are obtained, storing the corresponding compensation parameters in a driving controller of the display screen.

[0019] In some embodiments, the compensation parameters obtained in the i-th calculation step overwrite the compensation parameters obtained in the i-1-th calculation step.

[0020] In some embodiments, the number of different grayscale signals input to the display screen in each calculation process is 2-8.

[0021] In another aspect, the disclosed embodiments include a signal generator arranged to generate different grey scale signals and sequentially output the generated different grey scale signals to a display screen; an image capturing device configured to capture images displayed on the display screen with different gray scale signals in each calculation process; a processor coupled to the image capture device, configured to extract brightnesses of different gray scale signals of each pixel point from each captured image, and calculate compensation parameters of each pixel point in each calculation step according to the extracted brightnesses; further coupled to the signal generator, configured to control the signal generator to generate different gray scale signals; a memory coupled to the processor and configured to store, after each calculation process, the compensation parameters obtained in the current calculation process; a compensation member coupled between the signal generator and the display screen, further coupled to the memory, arranged to read compensation parameters obtained in a previous calculation process from the memory in a current calculation process, and compensate for initial luminance (luminance of each pixel point in a different grayscale signal obtained in a first calculation process) in different grayscale signals of each pixel point based on the compensation parameters, thereby displaying a compensated image on the display screen, and further arranged to read compensation parameters obtained in a last calculation process from the memory in a process of actually displaying on the display screen, and compensate for luminance to be displayed by each pixel point based on the compensation parameters; A pixel point luminance compensation device is further provided.

[0022] In some embodiments, the compensation device comprises: The apparatus further includes a data writing device coupled between the processor and the memory for writing the compensation parameters calculated in each calculation step into the memory.

[0023] In some embodiments, the memory and the compensation element are integrated into a driver controller of the display screen.

[0024] In another aspect, the disclosed embodiments include comprising one or more processors arranged to execute computer instructions to perform, for example, one or more steps of the pixel point luminance compensation method described herein; Computer products are further provided.

[0025] In another aspect, the disclosed embodiments include storing computer-executable instructions that, when executed by one or more processors, cause the one or more processors to perform one or more steps in a pixel point luminance compensation method described herein; A computer readable storage medium is further provided. [Brief description of the drawings]

[0026] In order to more clearly describe the technical solutions in the embodiments of the present disclosure or the prior art, the following briefly introduces the drawings used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some of the embodiments of the present disclosure. Those skilled in the art can obtain other drawings from these drawings without exerting their imagination. [Figure 1] FIG. 1 is a flow chart showing steps of each calculation process in the compensation method provided in the embodiment of the present disclosure. [Diagram 2] FIG. 2 is a conceptual diagram of a pixel point in the compensation method provided by the embodiment of this disclosure. [Diagram 3] FIG. 3 is a conceptual diagram of the initial brightness-difference parameter curve obtained by fitting. [Figure 4] FIG. 4 is a flowchart of the compensation process when actually displaying in the compensation method provided in the embodiment of the present disclosure. [Diagram 5] FIG. 5 is a flowchart of a compensation method provided by an embodiment of the present disclosure. [Figure 6] FIG. 6 is a basic structural diagram of a compensation device provided in an embodiment of this disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] In order to make the above objectives, features and advantages of the present disclosure clearer and easier to understand, the following will clearly and completely describe the technical solutions in the embodiments of the present disclosure in combination with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only some of the embodiments of the present disclosure, and are not all of the embodiments. Based on the embodiments in the present disclosure, any other embodiments obtained by a person skilled in the art without exerting his or her creative efforts are all within the scope of the claims of the present disclosure.

[0028] As mentioned in the background art, conventional optical compensation uses CCD to extract the luminance or light-dark contrast for pixel points on the full screen, finds the luminance difference between each pixel point and a reference pixel point, and compensates each pixel point accordingly. However, this optical compensation method has the problem of compensation anomalies (so-called "over-compensation") at pixel points with too large luminance differences, which reduces the accuracy of compensation.

[0029] The main cause of this problem is that the CCD is a planar charge-coupled device that can convert optical signals into electrical signals, which are then converted into digital signals and output. The magnitude of the output signal depends on the exposure time; the longer the exposure time, the larger the output signal. However, since the exposure time for all pixel points on the entire display screen by the CCD is the same, pixel points with excessively large brightness differences have an underexposure problem. As a result, the signal collected for the pixel point becomes too small, and if compensation is made based on this, an over-compensation problem occurs. This is what the inventors of the present disclosure discovered through research.

[0030] Due to the existence of the over-compensation problem, the conventional compensation method can only compensate for pixel points whose compensation luminance difference is within a certain range, the compensation range is limited, and effective compensation cannot be achieved for pixel points whose luminance difference is relatively large, and the overall compensation effect is not ideal.

[0031] Based on the above research, the disclosed embodiment provides a pixel point luminance compensation method. Figure 1 is a step flow chart of each calculation process in the compensation method provided by the disclosed embodiment. As shown in Figure 1, in some embodiments, the compensation method includes N calculation processes (N≧2). Among them, each calculation process includes the following steps S(N1) to S(N4):

[0032] In step S(N1), different grayscale signals are sequentially input to the display screen, an image displayed on the display screen with the different grayscale signals is acquired, and the luminance of each pixel point with the different grayscale signals is extracted from the image.

[0033] In one embodiment, the process in the above step S(N1) may be the following process. If the number of gray scale signals sequentially input to the display screen in each calculation process is M (M≧2), then G 1 , G 2 , ……, G M First, the grayscale signal G 1 By inputting the above, the same gray scale is displayed on all pixel points of the display screen, and the gray scale signal G of the display screen is input using a CCD image pickup device, for example. 1 Then, the image 1 is captured, and the input grayscale signal G 1 G 2 Switch to the grayscale signal G on the display screen. 2 In this way, different grayscale signals are sequentially input, and the input grayscale signal G M is the grayscale signal on the display screen G M Take corresponding images until image M at is obtained.

[0034] Let us suppose that the number of pixels included in the display screen is D, and each pixel is P 1 , P 2 , ……, P D and pixel point P 1 ~P D Luminance of {L 1,1 , L 2,1 , ……, LD,1} and extract pixel point P from image 2. 1 ~P D Luminance of {L 1,2 , L 2,2 , ……, L D,2}, ..., extract pixel point P from image M 1 ~P D Luminance of {L 1,M , L 2,M , ……, L D,M} is extracted, and the brightness of each pixel point is extracted from each image obtained by shooting in this way. 1 Grayscale signal G 1 ~G M The luminance at each 1,1 , L 1,2 , ……, L 1,M}, pixel point P 2 Grayscale signal G 1 ~G M The luminance at each 2,1 , L 2,2 , ……, L 2,M}, ..., pixel point P D Grayscale signal G 1 ~G M The luminance at each D,1 , L D,2 , ……, L D,M}.

[0035] It should be noted that the number M of different gray scale signals input to the display screen in each calculation process can be selected according to actual needs. The larger the value of M, the more data is available for calculating the compensation parameters, and the more accurate the calculated compensation parameters are, which is conducive to improving the compensation effect; the smaller the value of M, the smaller the amount of calculation required to calculate the compensation parameters, and the easier and faster the calculation process is. For example, the value of M can be 2 to 8, and in one example, it can be 6.

[0036] In step S(N2), a reference pixel point is determined from each pixel point included in the display screen, and a difference parameter of the luminance of each pixel point in different gray scale signals with respect to the luminance of the reference pixel point in the corresponding gray scale signal is calculated.

[0037] FIG. 2 is a conceptual diagram of a pixel point in the compensation method provided in the embodiment of the present disclosure. In the above step S(N2), as shown in FIG. r is an arbitrary pixel point P among all the pixel points included in the display screen. x (x=1 to D), in other words, the reference pixel point P r is all pixel points P 1 ~P D For example, the pixel point at the center of the display screen is the reference pixel point P r From step S(N1), the grayscale signals G 1 ~G M Since the luminance at the reference pixel point P is known, r Grayscale signal G 1 ~G M The brightness at r 1 , L r 2 , ……, L r M} is written as

[0038] In this step, the difference parameter of the luminance in a grayscale signal of a pixel point relative to the luminance in the corresponding grayscale signal of the reference pixel point can be defined as the inverse of the ratio of the two luminance values, and the difference parameter of each pixel point can be calculated respectively based on the following equation (1).

[0039]

number

[0040] Among them, j=1~M, x=1~D, L r j is the reference pixel point P rThe luminance of the j-th grayscale signal in L x,j is the x-th pixel point P x The luminance of the j-th grayscale signal, Q x,j is the reference pixel point P r The jth grayscale signal of the xth pixel point P x is the luminance difference parameter for the j-th grayscale signal of

[0041] As can be seen from the above calculation, pixel point P 1 Grayscale signal G 1 ~G M The difference parameter in is {Q 1,1 , Q 1,2 , …, Q 1,M}, pixel point P 2 Grayscale signal G 1 ~G M The difference parameter in is {Q 2,1 , Q 2,2 , …, Q 2,M}, ..., pixel point P D Grayscale signal G 1 ~G M The difference parameter in is {Q D,1 , Q D,2 , …, Q D,M}, which is a total of D sets of difference parameter data.

[0042] The point to be explained is the reference pixel point P r is pixel point P 1 ~P D Since the pixel is a point in the pixel area, as can be seen from the above equation (1), the reference pixel point P r The difference parameter of is 1. Therefore, in the D sets of difference parameter data, the difference parameter in one set of data (i.e., the reference pixel point P r ) are all 1.

[0043] In step S(N3), the difference parameter of each pixel point and the initial brightness of the corresponding pixel point in different grayscale signals are fitted to obtain an initial brightness-difference parameter curve of each pixel point.

[0044] It should be noted that in the above step S(N3), the initial luminance refers to the luminance of different gray scale signals of each pixel point obtained in the first calculation process. 1 Grayscale signal G 1 ~G M The initial luminance at is {L 0 1,1 , L 0 1,2 , ……, L 0 1,M}, and the pixel point P 2 Grayscale signal G 1 ~G M The initial luminance at is {L 0 2,1 , L 0 2,2 , ……, L 0 2,M}, and the pixel point P D Grayscale signal G 1 ~G M The initial luminance at is {L 0 2,1 , L 0 2,2 , ……, L 0 2,M} can be expressed as:

[0045] The fitting performed in step S(N3) above can be selected from linear function fitting, quadratic function fitting, higher order function fitting, exponential function fitting, etc. In the following, linear function fitting will be described as an example. The initial brightness-difference parameter curve obtained by linear function fitting is a straight line, and FIG. 3 is a conceptual diagram of the initial brightness-difference parameter curve obtained by fitting. As shown in FIG. 3, in the initial brightness-difference parameter curve, the horizontal axis is the initial brightness, and the vertical axis is the difference parameter. For each pixel point, its grayscale signal G1 ~G M If the initial luminance values ​​and the difference parameter values ​​at each pixel point P are known, that is, M points are known, a straight line can be obtained by fitting based on these M points. 1 ~P D D initial brightness-difference parameter curves corresponding to the above are obtained.

[0046] The fitting process is a process of estimating unknown points based on known points. The initial brightness before fitting refers to the brightness of different grayscale signals of pixel points obtained in the first calculation process, and each pixel point in the first calculation has not yet been compensated. The initial brightness after fitting can be any value on the horizontal axis, so the initial brightness at this time has a broader meaning and should refer to the brightness when no compensation is performed on different grayscale signals of pixel points.

[0047] In step S(N4), the compensation parameters of each pixel point are calculated based on the initial brightness-difference parameter curve of each pixel point.

[0048] Specifically, the above step S(N4) can adopt the following process.

[0049] First, the initial brightness-difference parameter curve of each pixel point is expressed using the following equation (2).

[0050]

number

[0051] Among them, Q x is the difference parameter of the luminance of the grayscale signal of the x-th pixel point from the luminance of the corresponding grayscale signal of the reference pixel point, L 0 x is the initial luminance of the corresponding grayscale signal of the xth pixel point, K' x , K.” x is a coefficient.

[0052] Since the initial brightness-difference parameter curve of each pixel point is a straight line, the initial brightness-difference parameter curve of each pixel point can be expressed using the above linear function. For example, for pixel point P 1 The expression of the initial brightness-difference parameter curve is

number

number

number

[0053] Then, K' x , K.” x Calculate the value of K' x Let K” be the first compensation parameter of the x-th pixel point. x Let K' be the second compensation parameter of the x-th pixel point. Since we have already obtained the initial brightness-difference parameter curve of the pixel point by fitting, x The process of calculating the value of K” is the process of calculating the slope of the initial brightness-difference parameter curve. x The process of calculating the value of is the process of calculating the vertical axis intercept of the initial luminance-difference parameter curve. For example, 1 The first compensation parameter K' 1 and the second compensation parameter K” 1 , pixel point P 2 The first compensation parameter K' 2 and the second compensation parameter K” 2 , ..., pixel point P D The first compensation parameter K' D and the second compensation parameter K” DThe point to be explained is that the first compensation parameter K' for each pixel point obtained by calculation is x and the second compensation parameter K” x It is important to clarify that θ is only a compensation parameter obtained in the current calculation process, and is not the same as the compensation parameter obtained in each calculation process.

[0054] In this embodiment, the above steps S(N1) to S(N4) are executed in each calculation process to obtain the corresponding compensation parameters. For example, in the i-th calculation process, i=2 to N, and the image displayed on the display screen with different grayscale signals is an image obtained by compensating the initial luminance of each pixel point with different grayscale signals based on the compensation parameters obtained from the (i-1)th calculation process. In other words, the grayscale signal G of the display screen obtained by shooting in the first calculation process is 1 ~G M The images 1 to M in the above are images that have not yet been compensated, and the grayscale signals G of the display screen obtained by shooting in each calculation process in the second to Nth calculation processes are 1 ~G M Images 1 to M in are images after compensation is performed using the compensation parameters obtained in the previous calculation process. As a result, in the second to Nth calculation processes, the luminance of each pixel point on which the calculation of the compensation parameters is based in each calculation process is set to the luminance obtained after the luminance of each pixel point is compensated using the compensation parameters obtained in the previous calculation process.

[0055] In the above scheme, in the i-th (i=2~N) calculation process, the initial brightness of each pixel point with different grayscale signals is compensated based on the compensation parameters obtained in the (i-1)th calculation process, so that a compensated image is displayed on the display screen. This step can be realized by the following method.

[0056] First, calculate the compensation luminance at different gray scale signals of each pixel point according to the following formula (3).

[0057]

number

[0058] Among them, L x,j is the compensation luminance of the jth grayscale signal at the xth pixel point, L 0 x,j is the initial luminance of the jth grayscale signal at the xth pixel point, K' x , K.” x is the compensation parameter obtained in the (i-1)th calculation process.

[0059] The "compensated luminance" refers to the luminance obtained after compensation is performed on the initial luminance in the grayscale signal at a pixel point (i.e., the luminance in the grayscale signal at the x-th pixel point in the first calculation process, i.e., the luminance in the grayscale signal at the x-th pixel point without any compensation) using the compensation parameters obtained in the previous calculation process. x,j is the difference parameter Q of the luminance of the j-th grayscale signal of the x-th pixel point relative to the luminance of the j-th grayscale signal of the reference pixel point. x,j and the initial luminance L of the j-th grayscale signal at the x-th pixel point 0 x,j The product of

number

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number

[0060] Then, according to the corresponding relationship between the grayscale signal and the luminance, obtain the compensation grayscale signal corresponding to the compensation luminance of each pixel point in different grayscale signals. As for the display screen, there is a certain corresponding relationship between the grayscale signal input to the pixel point and the luminance of its light emission, and according to this corresponding relationship, the grayscale signal corresponding to the compensation luminance of the pixel point can be found, and this grayscale signal is called the compensation grayscale signal.

[0061] Then, the display screen displays different grayscale signals G 1 ~G M When inputting sequentially, for each pixel point, the input different gray scale signals G 1 ~G M are converted into corresponding compensation gray scale signals, so that each pixel point displays a corresponding compensation brightness.

[0062] It should be noted that each of the above calculation processes is arranged as an operation performed on a production line before the display screen is shipped, and the compensation parameters of the final calculation process are obtained through at least two calculation processes, and then the compensation parameters are stored in the driving controller of the display screen, so that when the display screen is actually used to display an image, the driving controller of the display screen adopts the compensation parameters of the final calculation process to compensate the brightness of each pixel point.

[0063] 4 is a flowchart of the compensation process in the compensation method provided in the embodiment of the present disclosure when actually displaying. Therefore, as shown in FIG. 4, the pixel point luminance compensation method in this embodiment may further include the following steps S01 to S05.

[0064] In step S01, in the process of actual display on the display screen, the uncompensated luminance corresponding to each pixel point in the image to be displayed on the display screen is obtained.

[0065] In step S02, the compensation parameters obtained in the Nth calculation process are read out.

[0066] In step S03, a compensated luminance after compensation is performed on each pixel point is calculated based on the following equation (4).

[0067]

number

[0068] Among them, L x is the compensation luminance for the x-th pixel point, L 0 x is the uncompensated luminance of the xth pixel point, K' x,N is the first compensation parameter of the x-th pixel point to be compensated obtained in the Nth calculation process, K x,N is the second compensation parameter of the x-th pixel point to be compensated in the N-th calculation process.

[0069] In step S04, a compensation grayscale signal corresponding to the compensation luminance of each pixel point is obtained from the correspondence relationship between the grayscale signal and the luminance.

[0070] In step S05, a corresponding compensation grayscale signal is input to each pixel point, thereby causing each pixel point to display a corresponding compensation luminance.

[0071] By executing steps S01 to S05, effective compensation of the luminance of each pixel point in the image to be displayed is realized using the compensation parameters obtained in the Nth calculation process.

[0072] In this embodiment, after each calculation process is completed and the compensation parameters are obtained, the corresponding compensation parameters can be stored in the driving controller of the display screen, so that when the next calculation process is performed, the driving controller can directly read the compensation parameters of the previous calculation process stored therein to compensate each pixel point.

[0073] In addition, when actually displaying on the display screen, the compensation of a pixel point only needs to be based on the compensation parameters obtained in the final (i.e., Nth) calculation process. Therefore, when storing the compensation parameters each time, the compensation parameters waiting to be stored can be directly used to overwrite the compensation parameters previously stored. That is, the compensation parameters obtained in the i-th calculation process overwrite the compensation parameters obtained in the (i-1)th calculation process, thereby saving the storage space in the driving controller and increasing the calculation speed.

[0074] The pixel point luminance compensation method provided in this embodiment includes at least two calculation steps, and in each calculation step, different grayscale signals are input, and luminance difference parameters of each pixel point and reference pixel point in different grayscale signals are calculated, and an initial luminance-difference parameter curve is obtained by fitting based on the difference parameter curve, and then a compensation parameter of the current calculation step is obtained by calculating based on the difference parameter curve. In addition, the image displayed on the display screen with different grayscale signals in the current calculation step is an image obtained by compensating the initial luminance of each pixel point in different grayscale signals according to the compensation parameters obtained in the previous calculation step.

[0075] Therefore, by repeating this process, the luminance difference between each pixel point and the reference pixel point can be successively reduced, and the compensation parameters obtained can be successively refined. Therefore, the compensation parameters obtained in the final calculation process have the highest accuracy, and if the luminance of the display screen is compensated based on this, a good compensation effect can be obtained.

[0076] In this way, for pixel points with a relatively large luminance difference, the present invention includes at least two calculation processes. In the first calculation process, the compensation parameters of the pixel points with a relatively large luminance difference are first extrapolated by a fitting method, that is, the compensation range is expanded, and the pixel points with a relatively large luminance difference are compensated based on this to improve the compensation effect (that is, the luminance difference between them and the reference pixel point is initially reduced), and then at least one calculation is performed after compensation to obtain the compensation parameters by interpolation, and the pixel points with a relatively large luminance difference are further compensated based on this to further reduce the luminance difference between them and the reference pixel point, thereby improving the compensation effect of the pixel points with a relatively large luminance difference and improving the luminance uniformity of the full screen.

[0077] FIG. 5 is a flow chart of the compensation method provided by the embodiment of the present disclosure. The pixel point luminance compensation method provided by the embodiment of the present disclosure will be described below with reference to FIG. 5. As shown in FIG. 5, if the compensation method includes a second calculation process (i.e., N=2), and there are two different gray scale signals input to the display screen in each calculation process, which are G 1 , G 2 There are a total of 100 pixel points P 1 ~P 100 If there is, the compensation method includes the following steps S11 to S35 (as shown in FIG. 5).

[0078] In step S11, a grayscale signal G is displayed on the display screen. 1 , G 2 are input sequentially, and the display screen shows a grayscale signal G 1 , G 2 The image to be displayed is captured, and the grayscale signal G for each pixel is calculated. 1 , G 2 Extract the luminance at

[0079] Pixel point P 1 Grayscale signal G 1 , G 2 The luminance at is {L 1,1 , L 1,2}, Pixel point P 2Grayscale signal G 1 , G 2 The luminance at is {L 2,1 , L 2,2}, … Pixel point P 100 Grayscale signal G 1 , G 2 The luminance at is {L 100,1 , L 100,2}.

[0080] In step S12, a reference pixel point P r Confirm the reference pixel point P r Grayscale signal G 1 , G 2 Luminance at L r Grayscale signal G for each pixel point 1 , G 2 Calculate the difference parameter of luminance L at

[0081] Pixel point P 1 Regarding

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number

number

[0082] Among them, the reference pixel point P r The difference parameter is 1.

[0083] In step S13, the difference parameter of each pixel point and the initial brightness of the corresponding pixel point in different grayscale signals are fitted to obtain an initial brightness-difference parameter curve of each pixel point.

[0084] Pixel point P 1 Regarding the two known points (L 1,1 , Q 1,1 ) and (L 1,2 , Q 1,2 ) is fitted with a linear function to obtain the initial brightness-difference parameter curve 1,

number

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[0085] In step S14, compensation parameters for each pixel point are calculated based on the initial luminance-difference parameter curves 1 to 100 for each pixel point, and the compensation parameters for each pixel point obtained in the first calculation process are written into a memory that is driven and controlled by the display screen.

[0086] Pixel point P 1 With respect to the initial brightness-difference parameter curve 1, the slope K' 1 and vertical axis intercept K” 1 Calculate the first compensation parameter and the second compensation parameter, Pixel point P 2 With respect to the initial brightness-difference parameter curve 2, the slope K' 2 and vertical axis intercept K” 2 Calculate the first compensation parameter and the second compensation parameter, … Pixel point P 100 With respect to the initial brightness-difference parameter curve 100, the slope K' 100 and vertical axis intercept K” 100 are calculated and used as the first compensation parameter and the second compensation parameter.

[0087] The above steps S11 to S14 are the first calculation process. In this calculation process, the compensation range can be expanded by fitting, and even if the pixel point has a large luminance difference, a preliminary luminance compensation can be performed based on the first compensation parameter and the second compensation parameter obtained by calculation, that is, the compensation luminance value is extrapolated to reduce the luminance difference between it and the reference pixel point in a preliminary manner.

[0088] In step S21, a grayscale signal G is displayed on the display screen. 1 , G 2 The compensation parameters for each pixel point obtained in the first calculation process are read out, and the luminance of each pixel point in the image to be displayed is compensated based on the compensation parameters, so that the compensated image is displayed on the display screen, and the display screen displays a grayscale signal G 1 , G 2 The image after compensation is captured and the grayscale signal G for each pixel is calculated.1 , G 2 Extract the luminance at

[0089] Pixel point P 1 Grayscale signal G 1 , G 2 The luminance at is {L' 1,1 , L' 1,2}, Pixel point P 2 Grayscale signal G 1 , G 2 The luminance at is {L' 2,1 , L' 2,2}, … Pixel point P 100 Grayscale signal G 1 , G 2 The luminance at is {L' 100,1 , L' 100,2}.

[0090] A reference pixel point P to itself in the same grayscale signal r Since the difference parameter of is 1, the reference pixel point P r This means that there is no need to compensate for the brightness of the grayscale signal G 1 , G 2 The brightness at is still L r 1 , L r 2 It is.

[0091] In step S22, the reference pixel point P r Grayscale signal G 1 , G 2 Luminance at L r Grayscale signal G for each pixel point 1 , G 2 Calculate the difference parameter of the compensated luminance L' at

[0092] Pixel point P 1 Regarding

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[0093] In step S23, the difference parameter of each pixel point and the initial brightness of the corresponding pixel point in different grayscale signals are fitted to obtain a new initial brightness-difference parameter curve of each pixel point.

[0094] Pixel point P 1 Regarding the two known points (L 1,1 , Q' 1,1 ) and (L 1,2 , Q' 1,2 ) is fitted with a linear function to obtain the initial brightness-difference parameter curve 1',

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[0095] In step S24, new compensation parameters for each pixel point are calculated based on the new initial brightness-difference parameter curves 1' to 100' for each pixel point, and the new compensation parameters for each pixel point obtained in the second calculation process are written to a memory controlled by the drive of the display screen so that they overwrite the compensation parameters for each pixel point obtained in the first calculation process.

[0096] Pixel point P 1 With respect to the initial brightness-difference parameter curve 1', the slope K' 1 and vertical axis intercept K” 1 Calculate the first compensation parameter and the second compensation parameter,

[0097] Pixel point P 2 With respect to the initial brightness-difference parameter curve 2', the slope K' 2 and vertical axis intercept K” 2 Calculate the first compensation parameter and the second compensation parameter, … Pixel point P 100 With respect to the initial brightness-difference parameter curve 100', the slope K' 100 and vertical axis intercept K” 100 are calculated and used as the first compensation parameter and the second compensation parameter.

[0098] The above steps S21 to S24 are the second calculation process. In this calculation process, the image on which the compensation parameters are calculated is obtained by compensating the image to be displayed using the compensation parameters obtained in the first calculation process, and the compensation parameters are made more accurate by using a method called interpolation. Furthermore, when the compensation parameters obtained in the second calculation process are used to perform luminance compensation on a pixel point with a large luminance difference, the luminance difference between the pixel point and the reference pixel point can be further reduced, thereby improving the compensation effect and accuracy.

[0099] In step S31, during the actual display process of the display screen, the uncompensated luminance L corresponding to each pixel point in the image to be displayed on the display screen is calculated. 0 Get the.

[0100] Pixel point P 1 The uncompensated luminance of is L 0 1 and Pixel point P 2 The uncompensated luminance of is L 0 2 and … Pixel point P 100 The uncompensated luminance of is L 0 100 It is.

[0101] In step S32, the compensation parameters obtained in the second calculation process are read out.

[0102] Pixel point P obtained in the second calculation process 1 The first compensation parameter is K' 1,2 , the second compensation parameter is K” 1,2 and Pixel point P obtained in the second calculation process 2 The first compensation parameter is K' 2,2 , the second compensation parameter is K” 2,2 and … Pixel point P obtained in the second calculation process 100 The first compensation parameter is K' 100,2, the second compensation parameter is K” 100,2 It is.

[0103] In step S33, the compensation luminance L after compensation for each pixel point is calculated.

[0104]

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[0105] In S34, a compensation grayscale signal corresponding to the compensation luminance of each pixel point is obtained from the correspondence between the grayscale signal and the luminance.

[0106] In S35, a corresponding compensation grayscale signal is input to each pixel point, thereby causing each pixel point to display a corresponding compensation luminance.

[0107] The above steps S31 to S35 are the process of achieving luminance compensation when the display screen actually displays an image.

[0108] The embodiment of the present disclosure further provides a pixel point luminance compensation device. Figure 6 is a basic structural diagram of the compensation device provided by the embodiment of the present disclosure. As shown in Figure 6, the pixel point luminance compensation device may include the following components: a signal generator 1, an image capture device 2, a processor 3, a memory 4 and a compensation component 5.

[0109] The signal generator 1 may be arranged to generate different greyscale signals and output the generated different greyscale signals to the display screen 100 in sequence.

[0110] The image capture facility 2 may be arranged to capture images for display at different grey scale signals on the display screen 100 in each calculation process.

[0111] The processor 3 may be coupled to the image capture device 2 and configured to extract the brightness of each pixel point in different grayscale signals from each captured image, and calculate the compensation parameters of each pixel point in each calculation process based on the extracted brightness. The processor 3 may also be coupled to the signal generator 1 and configured to control the signal generator 1 to generate different grayscale signals, and the signal generator 1 may also feed back its own task execution status to the processor 3.

[0112] The memory 4 may be coupled to the processor 3 and is arranged to store, after each calculation process, the compensation parameters obtained in the current calculation process.

[0113] The compensation member 5 may be coupled between the signal generator 1 and the display screen 100, or may be further coupled to the memory 4, and in the current calculation process, the compensation member 5 reads out the compensation parameters obtained in the previous calculation process from the memory 4, and compensates for the initial luminance of each pixel point with different grayscale signals based on the compensation parameters, thereby displaying a compensated image on the display screen 100. In addition, the compensation member 5 may be arranged to read out the compensation parameters obtained in the final calculation process from the memory 4, and compensate for the luminance that each pixel point is to display based on the compensation parameters, in the process in which the display screen 100 actually displays.

[0114] It should be noted that the initial brightness refers to the brightness of different gray scale signals of each pixel point obtained in the first calculation process.

[0115] The above pixel point luminance compensation device can accurately calculate the compensation parameters required for luminance compensation for a pixel point, and the calculated compensation parameters can be used to compensate the luminance of each pixel point on the display screen 100. The compensation device can achieve effective compensation even for pixel points with relatively large luminance differences, without the problem of over-compensation, and the compensation effect is favorable, improving the luminance uniformity of the display screen.

[0116] Referring again to FIG. 6, in some embodiments, the pixel point luminance compensation device may include a data writing device 6, which may be coupled between the processor 3 and the memory 4, and is configured to write the compensation parameters obtained by calculation to the memory 4 in each calculation process.

[0117] In some embodiments, the memory 4 and the compensation element 5 can be integrated into the driving controller 200 of the display screen 100 to improve the integration of the display device structure, as shown in Fig. 6. The memory 4 can be a non-volatile memory, such as a read only memory (ROM), a flash memory, etc. The compensation element 5 and the data writing device 6 can be realized by an integrated circuit (IC), a dedicated integrated circuit, etc.

[0118] In some embodiments, as shown in FIG. 6 , the pixel point luminance compensation device may further include a power supply member 7, which can be coupled to the driving controller 200 and is configured to supply power to the driving controller 200 to ensure the normal operation of the memory 4 and the compensation member 5.

[0119] In addition, in the pixel point luminance compensation device of the disclosed embodiment, the image capture device 2 can be specifically an imaging device, such as a CCD, and the imaging device can capture an image displayed on the display screen 100 by shooting. The processor 3 can be a microprocessor, a microcontroller, a dedicated integrated circuit, a single-core processor, a multi-core processor, etc.

[0120] The embodiments of the present disclosure further provide a computer product. The computer product includes one or more processors, and the processors are configured to execute computer instructions to perform, for example, one or more steps in the pixel point luminance compensation method described in the embodiments of the present disclosure. The beneficial effects that the computer product can achieve are the same as the beneficial effects of the pixel point luminance compensation method described in the embodiments of the present disclosure, and therefore will not be described again here.

[0121] The disclosed embodiment further provides a computer-readable storage medium, in which executable instructions are stored, and when the executable instructions are executed by one or more processors, the one or more processors execute one or more steps of the pixel point luminance compensation method described in the disclosed embodiment. The beneficial effects that the computer-readable storage medium can achieve are the same as the beneficial effects of the pixel point luminance compensation method described in the disclosed embodiment, so they will not be described again here. The computer-readable storage medium may be a non-volatile storage medium, such as a read-only memory (ROM).

[0122] The above description is merely an exemplary embodiment of the present disclosure, and the scope of the claims of the present disclosure is not limited thereby. Any modifications or replacements that can be easily thought of by a person skilled in the art within the scope of the technology disclosed in the present disclosure are included in the scope of the claims of the present disclosure. Therefore, the scope of the claims of the present disclosure is based on the scope of the claims. [Explanation of symbols]

[0123] 1 Signal generator 2. Image acquisition equipment 3 Processors 4. Memory 5 Compensation materials 6 Data writing device 7 Power supply components 100 display screens 200 Drive controller

Claims

1. It includes N calculation steps, where N>=2. The calculation process for each round is as follows: Sequentially inputting a plurality of grayscale signals to a display screen, acquiring an image displayed on the display screen by the plurality of grayscale signals using a CCD imaging device, and extracting the luminance of each pixel point in the image by the plurality of grayscale signals; selecting one of the pixel points as a reference pixel point and calculating a difference parameter of the luminance of each pixel point relative to the luminance of the reference pixel point in the plurality of grayscale signals; performing function fitting on the difference parameter of each pixel point with the initial luminance of each pixel point in the plurality of grayscale signals to obtain an initial luminance-difference parameter curve of each pixel point; and calculating a compensation parameter for each pixel point based on an initial brightness-difference parameter curve for each pixel point to compensate for a brightness difference between each pixel in the image captured by the CCD imaging device due to underexposure of a CCD in the CCD imaging device; The initial luminance of each pixel point is a luminance of the plurality of grayscale signals obtained in a first calculation step of the calculation step; In the i-th calculation process, i=2 to N, and an image displayed on a display screen using the plurality of grayscale signals is an image obtained by compensating the initial luminance of each pixel point in the plurality of grayscale signals based on the compensation parameter obtained in the (i-1)-th calculation process; The step of calculating a difference parameter of the luminance of each pixel point with respect to the luminance of the reference pixel point in the plurality of grayscale signals includes: The number of the plurality of gray scale signals sequentially input to the display screen in each calculation process is M (M≧2), and the number of pixels included in the display screen is D; Calculating a difference parameter for each pixel point according to the following formula (1): [0010] where j=1 to M, x=1 to D, Lrj is the luminance of the reference pixel point in the jth grayscale signal, Lx,j is the luminance of the xth pixel point in the jth grayscale signal, and Qx,j is the difference parameter between the luminance of the reference pixel point in the jth grayscale signal and the luminance of the xth pixel point; performing function fitting on the difference parameter of each pixel point at an initial luminance of each pixel point in the plurality of grayscale signals includes performing linear function fitting on the difference parameter of each pixel point at an initial luminance of each pixel point in the plurality of grayscale signals; Calculating compensation parameters for each pixel point based on the initial luminance-difference parameter curve for each pixel point includes: expressing an initial brightness-difference parameter curve for each pixel point using the following formula (2): [0025] (wherein, Q x is a difference parameter between the luminance of the x-th pixel point and the luminance of the reference pixel point in a certain grayscale signal, L 0 x is the initial luminance of the x-th pixel point in the grayscale signal, and K' x and K" x are coefficients); calculating a value of K' x as a first compensation parameter for the x-th pixel point and a value of K" x as a second compensation parameter for the x-th pixel point; Including, Compensating the initial luminance of each pixel point in the plurality of grayscale signals includes: Calculating a compensation luminance of each pixel point in the plurality of gray scale signals according to the following formula (3): [0030] (wherein, L x,j is the compensation luminance of the x-th pixel point in the j-th grayscale signal, L 0 x,j is the initial luminance of the x-th pixel point in the j-th grayscale signal, K' x , K" x are the compensation parameters obtained in the (i-1)th calculation process). obtaining a compensation grayscale signal of each pixel point corresponding to a compensation luminance in the plurality of grayscale signals from the correspondence relationship between the grayscale signal and the luminance obtained in the first calculation process; converting a plurality of grayscale signals to be sequentially input to a display screen into compensation grayscale signals for each pixel point, thereby displaying a compensation luminance at each pixel point; Including, Pixel point luminance compensation method.

2. During the process of actually displaying the image on the display screen, Obtaining an uncompensated luminance of each pixel point in an image to be displayed by the display screen; Reading out the compensation parameters obtained in the Nth calculation process; Calculating the compensation luminance after compensation for each pixel point according to the following formula (4): [0045] (Of these, L x is the compensation luminance of the xth pixel point, L 0 x is the uncompensated luminance of the xth pixel point, K' x,N is the first compensation parameter of the x-th pixel point obtained in the Nth calculation process, K x,N is the second compensation parameter of the x-th pixel point obtained in the Nth calculation process), obtaining a compensation grayscale signal of each pixel point corresponding to the compensation luminance according to the correspondence between the grayscale signal and the luminance; inputting the compensation grayscale signal to each pixel point to display the compensation luminance at each pixel point; Further comprising: The pixel point luminance compensation method according to claim 1.

3. After each calculation process is completed and the compensation parameters are obtained, the compensation parameters are stored in the display screen drive controller. The pixel point luminance compensation method according to any one of claims 1 to 2.

4. The compensation parameters obtained in the i-th calculation process overwrite the compensation parameters obtained in the i-1th calculation process. The pixel point luminance compensation method according to claim 3.

5. The number of the plurality of gray scale signals input to the display screen in each calculation process is 2 to 8; The pixel point luminance compensation method according to any one of claims 1 to 2.

6. One or more processors configured to execute computer instructions to perform one or more steps of the pixel point luminance compensation method according to any one of claims 1 to 5, Computer products.

7. A method for pixel point luminance compensation comprising: storing computer-executable instructions, the computer-executable instructions, when executed by one or more processors, causing the one or more processors to perform one or more steps of the pixel point luminance compensation method according to any one of claims 1 to 5; A computer-readable storage medium.

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