Display screen brightness correction method and system

Abstract

The invention relates to the technical field of display screen control, in particular to a display screen brightness correction method and system, and the method comprises the steps: obtaining a camera image pixel and a first duty ratio; shooting to obtain an original image; extracting a cutout image by adopting a cutout algorithm; using an image super-resolution reconstruction algorithm and a shape correction algorithm to restore the matting image pixels into camera image pixels to obtain a first image; measuring to obtain first illuminance; equally dividing the first image into N image grids, and aggregating to obtain a color value matrix and a first brightness matrix; calculating by adopting a brightness adjustment optimization algorithm to obtain an optimal brightness adjustment rate of the display screen, and calculating to obtain a third duty ratio; and correcting the duty ratio of the display screen PWM dimming circuit to the third duty ratio. According to the invention, the optimal adjustment rate of the brightness of the display screen is calculated by adopting a brightness adjustment optimization algorithm, and the brightness correction of the display screen is realized by adjusting the duty ratio of the PWM dimming circuit of the display screen.

Description

Technical Field

[0001] The present invention relates to the technical field of display screen control, and in particular to a display screen brightness correction method and system. Background Art

[0002] Electronic instrument display screens have been widely used in daily life and industrial production. The display effect of the display screen directly affects the user experience, and the brightness of the display screen is one of the important indicators that affect the display effect and user experience. In the prior art, the display screen generally adopts LED backlight technology. By adjusting the duty cycle of the display screen PWM dimming circuit, the LED backlight brightness can be adjusted, thereby achieving the adjustment of the display screen brightness.

[0003] However, the existing display brightness adjustment methods have the following problems: first, the traditional brightness adjustment methods often need to set the duty cycle of the PWM dimming circuit through manual observation and subjective judgment, lack of objective quantitative standards and automated adjustment means, resulting in the display brightness adjustment effect relying on manual experience; second, the user's perception of the display brightness is affected by the ambient light intensity, but the existing methods do not fully consider the impact of ambient light on the display effect, and cannot adaptively adjust the display brightness according to the actual use environment; third, under the influence of ambient light, the brightness of different areas of the display perceived by the user is non-uniform, and the traditional method fails to consider the non-uniformity of the display brightness perceived by the user, thereby affecting the display brightness adjustment effect.

[0004] In order to overcome the problems existing in the existing technology, there are still two major technical difficulties that need to be solved: first, the brightness of the display screen perceived by the user is different from the actual brightness set of the display screen. How to quantitatively measure the brightness of the display screen perceived by the user is a technical difficulty that needs to be solved; second, due to the influence of ambient light, the brightness of the display screen perceived by the user is non-uniform. How to set the optimization adjustment goal so that the brightness of the display screen perceived by the user reaches the overall optimal is also a technical difficulty that needs to be solved.

[0005] In order to solve the above technical problems, it is urgently necessary to provide a method that can accurately measure the brightness distribution of the display screen perceived by the user, comprehensively consider the influence of ambient illumination, and realize accurate correction of the brightness of the display screen. Summary of the invention

[0006] (1) Technical issues to be solved

[0007] The object of the present invention is to provide a display screen brightness correction method and system, so as to realize accurate display screen brightness correction according to the display screen brightness distribution perceived by the user and taking into account the influence of the ambient illumination.

[0008] (2) Technical solution

[0009] To achieve the above object, the present invention provides a display screen brightness correction method, the method comprising the following steps:

[0010] S1, obtaining first data, wherein the first data includes preset camera image pixels and a first duty cycle; the camera image pixels include a camera image pixel height and a camera image pixel width; the first duty cycle represents a duty cycle preset by a display screen PWM dimming circuit without correction.

[0011] S2, directing the camera lens rigidly fixed on the surface of the display screen toward the display screen to capture an original image; using a cutout algorithm to extract the captured image of the display screen surface in the original image, recorded as a cutout image; using an image super-resolution reconstruction algorithm and a shape correction algorithm to restore the pixels of the cutout image to camera image pixels, to obtain a first image; using an illuminance meter rigidly fixed on the surface of the display screen to measure the ambient illuminance, to obtain a first illuminance; according to the camera image pixels, dividing the first image into N image grids according to a preset number of horizontal and vertical divisions, recorded as the first image grid to the Nth image grid; calculating the RGB color values ​​of the pixels in the N image grids, and aggregating them to obtain a color value matrix; using a brightness conversion formula according to the color value matrix to calculate a first brightness matrix.

[0012] S3, according to a preset upper limit brightness matrix, a preset lower limit brightness matrix, a first brightness matrix, and a first illumination, an optimal adjustment rate of the brightness of the display screen is calculated using a brightness adjustment optimization algorithm; a functional relationship between the brightness adjustment rate of the display screen and the duty cycle change rate of the PWM dimming circuit of the display screen is obtained, which is recorded as a first function, and an optimal adjustment value of the duty cycle of the PWM dimming circuit of the display screen is calculated according to the optimal adjustment rate of the brightness of the display screen, the first function, and the first duty cycle, which is recorded as a second duty cycle; the first duty cycle is added to the second duty cycle to obtain a third duty cycle; the third duty cycle represents the optimal duty cycle of the PWM dimming circuit of the display screen after correction.

[0013] S4, correcting the duty cycle of the display screen PWM dimming circuit to a third duty cycle.

[0014] Furthermore, the method of calculating the RGB color values ​​of pixels in N image grids and aggregating them to obtain a color value matrix includes:

[0015] The number of pixels M is calculated according to the pixel height and pixel width of the camera image; the calculation formula of the number of pixels is:

[0016] M = h1 × h2;

[0017] Where h1 represents the pixel height of the camera image, and h2 represents the pixel width of the camera image.

[0018] The first image is pixel-decomposed to obtain M pixel points; the RGB color values ​​of the M pixel points are calculated using an image processing algorithm to obtain the R value, G value and B value of the M pixel points; the R value, G value and B value of the pixel points falling into the first image grid to the Nth image grid are averaged to obtain a color value matrix; the color value matrix is ​​expressed as:

[0019]

[0020] Among them, S represents the color value matrix; R u,l represents the average value of the R value of the pixels in the u×lth image grid; G u,l represents the average value of the G value of the pixels in the u×lth image grid; B u,l Represents the average value of the B value of the pixel points in the u×l-th image grid; u is an integer variable with a value from 1 to d1; l is an integer variable with a value from 1 to d2; d1 is the number of horizontal divisions, and d2 is the number of vertical divisions.

[0021] Furthermore, the method of calculating the first brightness matrix using a brightness conversion formula according to the color value matrix includes:

[0022] The first brightness matrix Y1 is calculated using the brightness conversion formula according to the color value matrix; the first brightness matrix is ​​expressed as:

[0023]

[0024] The brightness conversion formula is:

[0025]

[0026] Among them, Q u,l represents the element in the uth row and lth column of the first brightness matrix; Z max(u,l) Represents R u,l , G u,l , B u,l The maximum value of Z min(u,l) Represents R u,l , G u,l , B u,l The minimum value of .

[0027] Furthermore, the method of calculating the optimal adjustment rate of display screen brightness by using a brightness adjustment optimization algorithm according to a preset upper limit brightness matrix, a preset lower limit brightness matrix, a first brightness matrix, and a first illumination includes:

[0028] A first objective function is constructed according to the upper limit brightness matrix, the lower limit brightness matrix, the first brightness matrix, and the first illumination; the first objective function is expressed as:

[0029]

[0030] Wherein, V1(α) represents the first objective function; the independent variable of the first objective function is α, α represents the brightness adjustment rate of the display screen; Y min Represents the lower limit brightness matrix; Y max represents the upper limit brightness matrix; H represents the first illuminance, in lux; k represents the preset perceived illuminance, in lux; T1 represents the first duty cycle; express The F-norm represents the total length of all elements of the matrix in the Euclidean space.

[0031] Construct the first constraint condition; the first constraint condition is:

[0032]

[0033] in, Indicates Y1 The number of elements with negative values; r1 express The number of elements in which the value is negative.

[0034] Taking the minimum value of the first objective function as the goal and the first constraint condition as the constraint condition, the particle swarm optimization algorithm is used to calculate the optimal value of α, which is recorded as the optimal adjustment rate of the display brightness α * .

[0035] Further, the method of obtaining the functional relationship between the display screen brightness adjustment rate and the display screen PWM dimming circuit duty cycle change rate, recorded as the first function, and calculating the optimal adjustment value of the display screen PWM dimming circuit duty cycle according to the display screen brightness optimal adjustment rate, the first function, and the first duty cycle, recorded as the second duty cycle, includes:

[0036] The functional relationship between the display screen brightness adjustment rate and the display screen PWM dimming circuit duty cycle change rate is obtained, which is recorded as a first function; the first function is expressed as:

[0037] α=f1(β)=β;

[0038] Wherein, f1(β) represents the first function; β represents the duty cycle change rate of the display screen PWM dimming circuit.

[0039] According to the optimal adjustment rate of the brightness of the display screen, the first function, and the first duty cycle, the optimal adjustment value of the duty cycle of the display screen PWM dimming circuit is calculated using the duty cycle adjustment formula, which is recorded as the second duty cycle; the duty cycle adjustment formula is:

[0040] T2=α * T1;

[0041] Wherein, T2 represents the second duty cycle.

[0042] Based on the same inventive concept, on the other hand, the present invention also provides a display screen brightness correction system, the system comprising:

[0043] A data reading module is used to obtain first data, wherein the first data includes preset camera image pixels and a first duty cycle; the camera image pixels include camera image pixel height and camera image pixel width; the first duty cycle represents a duty cycle preset by a display screen PWM dimming circuit without correction.

[0044] The brightness calculation module is connected to the data reading module and is used to point the camera lens rigidly fixed on the surface of the display screen toward the display screen to capture an original image; use a cutout algorithm to extract the captured image of the display screen surface in the original image, which is recorded as a cutout image; use an image super-resolution reconstruction algorithm and a shape correction algorithm to restore the pixels of the cutout image to camera image pixels to obtain a first image; use an illuminance meter rigidly fixed on the surface of the display screen to measure the ambient illumination to obtain a first illumination; divide the first image into N image grids according to a preset number of horizontal divisions and a preset number of vertical divisions according to the camera image pixels, which are recorded as the first image grid to the Nth image grid; calculate the RGB color values ​​of the pixels in the N image grids, and aggregate them to obtain a color value matrix; and use a brightness conversion formula to calculate the first brightness matrix according to the color value matrix.

[0045] The optimization calculation module is connected to the brightness calculation module and is used to calculate the optimal adjustment rate of the brightness of the display screen by using the brightness adjustment optimization algorithm according to a preset upper limit brightness matrix, a preset lower limit brightness matrix, a first brightness matrix, and a first illumination; obtain the functional relationship between the brightness adjustment rate of the display screen and the duty cycle change rate of the PWM dimming circuit of the display screen, which is recorded as the first function, and calculate the optimal adjustment value of the duty cycle of the PWM dimming circuit of the display screen according to the optimal adjustment rate of the brightness of the display screen, the first function, and the first duty cycle, which is recorded as the second duty cycle; the first duty cycle is added to the second duty cycle to obtain a third duty cycle; the third duty cycle represents the optimal duty cycle of the PWM dimming circuit of the display screen after correction.

[0046] The correction module is connected to the optimization calculation module and is used to correct the duty cycle of the display screen PWM dimming circuit to a third duty cycle.

[0047] Furthermore, the brightness calculation module includes:

[0048] The pixel decomposition module is used to calculate the number of pixels M according to the pixel height and pixel width of the camera image; the calculation formula of the number of pixels is:

[0049] M = h1 × h2;

[0050] Where h1 represents the pixel height of the camera image, and h2 represents the pixel width of the camera image.

[0051] The color value matrix calculation module is connected to the pixel decomposition module and is used to decompose the first image into M pixels; calculate the RGB color values ​​of the M pixels using an image processing algorithm to obtain the R value, G value and B value of the M pixels; average the R value, G value and B value of the pixels falling into the first image grid to the Nth image grid to obtain a color value matrix; the color value matrix is ​​expressed as:

[0052]

[0053] Among them, S represents the color value matrix; R u,l represents the average value of the R value of the pixels in the u×lth image grid; G u,l represents the average value of the G value of the pixels in the u×lth image grid; B u,l Represents the average value of the B value of the pixel points in the u×l-th image grid; u is an integer variable with a value from 1 to d1; l is an integer variable with a value from 1 to d2; d1 is the number of horizontal divisions, and d2 is the number of vertical divisions.

[0054] Furthermore, the brightness calculation module also includes:

[0055] The first brightness matrix calculation module is used to calculate the first brightness matrix Y1 according to the color value matrix using the brightness conversion formula; the first brightness matrix is ​​expressed as:

[0056]

[0057] The brightness conversion formula is:

[0058]

[0059] Among them, Q u,l represents the element in the uth row and lth column of the first brightness matrix; Z max(u,l) Represents R u,l , G u,l , B u,l The maximum value of Z min(u,l) Represents R u,l , G u,l , B u,l The minimum value of .

[0060] Furthermore, the optimization calculation module includes:

[0061] The first objective function construction module is used to construct a first objective function according to the upper limit brightness matrix, the lower limit brightness matrix, the first brightness matrix, and the first illumination; the first objective function is expressed as:

[0062]

[0063] Wherein, V1(α) represents the first objective function; the independent variable of the first objective function is α, α represents the brightness adjustment rate of the display screen; Y min Represents the lower limit brightness matrix; Y max represents the upper limit brightness matrix; H represents the first illuminance, in lux; k represents the preset perceived illuminance, in lux; T1 represents the first duty cycle; express The F-norm represents the total length of all elements of the matrix in the Euclidean space.

[0064] The first constraint condition building module is connected to the first objective function building module and is used to construct a first constraint condition; the first constraint condition is:

[0065]

[0066] in, express The number of elements with negative values; express The number of elements in which the value is negative.

[0067] The particle swarm optimization calculation module is connected to the first constraint condition construction module, and is used to take the first objective function value as the minimum and the first constraint condition as the constraint condition, and use the particle swarm optimization algorithm to calculate the optimal value of α, which is recorded as the optimal adjustment rate of the display brightness α * .

[0068] Furthermore, the optimization calculation module also includes:

[0069] The first function building module is used to obtain the functional relationship between the display screen brightness adjustment rate and the display screen PWM dimming circuit duty cycle change rate, which is recorded as the first function; the first function is expressed as:

[0070] α=f1(β)=β;

[0071] Wherein, f1(β) represents the first function; β represents the duty cycle change rate of the display screen PWM dimming circuit.

[0072] The second duty cycle calculation module is connected to the first function construction module and is used to calculate the optimal adjustment value of the duty cycle of the display screen PWM dimming circuit according to the optimal adjustment rate of the display screen brightness, the first function, and the first duty cycle, and record it as the second duty cycle; the duty cycle adjustment formula is:

[0073] T2=α * T1;

[0074] Wherein, T2 represents the second duty cycle.

[0075] (3) Beneficial effects

[0076] Compared with the prior art, the present invention has the following beneficial effects:

[0077] 1. A camera lens rigidly fixed on the surface of a display screen is pointed toward the display screen to capture an original image. A cutout algorithm, an image super-resolution reconstruction algorithm, and a shape correction algorithm are used to obtain a first image. The first image simulates the user's visual perception of the display screen image, thereby achieving a quantitative measurement of the user's perception of the display screen brightness.

[0078] 2. According to the preset upper limit brightness matrix, the preset lower limit brightness matrix, the first brightness matrix, and the first illumination, the brightness adjustment optimization algorithm is used to calculate the optimal adjustment rate of the display brightness, and further calculate the third duty cycle, that is, the optimal duty cycle of the display PWM dimming circuit after correction. By correcting the duty cycle of the display PWM dimming circuit to the third duty cycle, the optimization correction of the display brightness is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0079] Figure 1 is a flowchart of a display screen brightness correction method according to Embodiment 1 of the present invention;

[0080] Figure 2 Schematic diagram of the module composition of the display screen brightness correction system according to Embodiment 2 of the present invention. DETAILED DESCRIPTION

[0081] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0082] Before giving examples, it is necessary to explain the application scenarios conceived by the present invention. The present invention is applied in user usage scenarios to optimize and adjust the duty cycle of the PWM dimming circuit of a display screen that uses LED backlight technology according to the ambient illumination and the display screen brightness perceived by the user, thereby achieving correction of the display screen brightness.

[0083] Example 1: Figure 1 As shown, this embodiment provides a display screen brightness correction method, the method comprising the following steps:

[0084] S1, obtaining first data, wherein the first data includes preset camera image pixels and a first duty cycle; the camera image pixels include a camera image pixel height and a camera image pixel width; the first duty cycle represents a duty cycle preset by a display screen PWM dimming circuit without correction.

[0085] Exemplarily, the display screen adopts LED backlight technology, and the brightness of the display screen can be adjusted by adjusting the brightness of the LED backlight. The adjustment of the brightness of the LED backlight is achieved by controlling the duty cycle of the PWM dimming circuit of the display screen. Therefore, by adjusting the duty cycle of the PWM dimming circuit of the display screen, the brightness of the display screen can be adjusted. The camera image pixel represents the pixel of the image taken by the camera rigidly fixed to the surface of the display screen. The camera image pixel height is 720, and the camera image pixel width is 1280. The first duty cycle is obtained by reading the PWM dimming circuit parameters, and the first duty cycle is 0.8.

[0086] S2, directing the camera lens rigidly fixed on the surface of the display screen toward the display screen to capture an original image; using a cutout algorithm to extract the captured image of the display screen surface in the original image, recorded as a cutout image; using an image super-resolution reconstruction algorithm and a shape correction algorithm to restore the pixels of the cutout image to camera image pixels, to obtain a first image; using an illuminance meter rigidly fixed on the surface of the display screen to measure the ambient illuminance, to obtain a first illuminance; according to the camera image pixels, dividing the first image into N image grids according to a preset number of horizontal and vertical divisions, recorded as the first image grid to the Nth image grid; calculating the RGB color values ​​of the pixels in the N image grids, and aggregating them to obtain a color value matrix; using a brightness conversion formula according to the color value matrix to calculate a first brightness matrix.

[0087] Exemplarily, a camera lens rigidly fixed to the surface of a display screen is directed toward the display screen to obtain an original image. The original image reflects the display screen image perceived by the user. The camera is fixed to the surface of the display screen by a bracket with a length of 0.2 meters, and the angle between the camera lens axis and the surface of the display screen is a preset first angle. The preset first angle is 90 degrees. The camera lens is directed toward the surface of the display screen, and the original image captured includes a captured image of the display screen surface and an image of the surrounding environment within the lens field of view. The original image is input into Adobe Photoshop software, and the captured image of the display screen surface is extracted by a cutout algorithm built into the software to obtain a cutout image. The pixel height and pixel width of the cutout image are respectively smaller than the pixel height and pixel width of the camera image. The cutout image is input into Adobe Photoshop software, and the pixels of the cutout image are restored to the pixels of the camera image by using the image super-resolution reconstruction algorithm and shape correction algorithm built into the software to obtain a first image. The pixel height of the first image is 720, and the pixel width is 1280. The ambient illuminance is measured by an illuminance meter rigidly fixed to the surface of the display screen, and the first illuminance is 347 lux. The preset number of horizontal divisions is 72, and the number of vertical divisions is 128. Therefore, the first image is equally divided into 9216 image grids, recorded as the first image grid to the 9216th image grid. Each image grid contains 100 pixels. The RGB color values ​​of the pixels in the 9216 image grids are calculated and aggregated to obtain a color value matrix. The first brightness matrix is ​​calculated based on the color value matrix using the brightness conversion formula. The first brightness matrix reflects the brightness distribution of the display screen perceived by the user.

[0088] S3, according to a preset upper limit brightness matrix, a preset lower limit brightness matrix, a first brightness matrix, and a first illumination, an optimal adjustment rate of the brightness of the display screen is calculated using a brightness adjustment optimization algorithm; a functional relationship between the brightness adjustment rate of the display screen and the duty cycle change rate of the PWM dimming circuit of the display screen is obtained, which is recorded as a first function, and an optimal adjustment value of the duty cycle of the PWM dimming circuit of the display screen is calculated according to the optimal adjustment rate of the brightness of the display screen, the first function, and the first duty cycle, which is recorded as a second duty cycle; the first duty cycle is added to the second duty cycle to obtain a third duty cycle; the third duty cycle represents the optimal duty cycle of the PWM dimming circuit of the display screen after correction.

[0089] For example, the optimal adjustment rate of the display brightness is calculated to be -0.32, and the second duty cycle is further calculated to be -0.256. Since the first duty cycle is 0.8, the third duty cycle is 0.544 obtained by adding the first duty cycle to the second duty cycle, so the optimal duty cycle of the display PWM dimming circuit after correction is 0.544.

[0090] S4, correcting the duty cycle of the display screen PWM dimming circuit to a third duty cycle.

[0091] For example, by adjusting the display screen PWM dimming circuit control system parameters, the duty cycle of the display screen PWM dimming circuit is corrected to the third duty cycle of 0.544, thereby achieving display screen brightness correction. The corrected display screen brightness is the most comfortable display screen brightness perceived by the user under the current ambient illumination.

[0092] Furthermore, the method of calculating the RGB color values ​​of pixels in N image grids and aggregating them to obtain a color value matrix includes:

[0093] The number of pixels M is calculated according to the pixel height and pixel width of the camera image; the calculation formula of the number of pixels is:

[0094] M = h1 × h2;

[0095] Where h1 represents the pixel height of the camera image, and h2 represents the pixel width of the camera image.

[0096] Exemplarily, the pixel height of the camera image is 720, the pixel width of the camera image is 1280, and the calculated number of pixels M is 921600.

[0097] The first image is pixel-decomposed to obtain M pixel points; the RGB color values ​​of the M pixel points are calculated using an image processing algorithm to obtain the R value, G value and B value of the M pixel points; the R value, G value and B value of the pixel points falling into the first image grid to the Nth image grid are averaged to obtain a color value matrix; the color value matrix is ​​expressed as:

[0098]

[0099] Among them, S represents the color value matrix; R u,l represents the average value of the R value of the pixels in the u×lth image grid; G u,l represents the average value of the G value of the pixels in the u×lth image grid; B u,l Represents the average value of the B value of the pixel points in the u×l-th image grid; u is an integer variable with a value from 1 to d1; l is an integer variable with a value from 1 to d2; d1 is the number of horizontal divisions, and d2 is the number of vertical divisions.

[0100] Exemplarily, the first image is pixel-decomposed to obtain 921,600 pixels. The RGB color values ​​of 921,600 pixels are calculated using the Python Pillow library image processing algorithm to obtain the R values, G values, and B values ​​of 921,600 pixels. The R values, G values, and B values ​​of the pixels falling into the first image grid to the 9216th image grid are averaged to obtain a color value matrix. The first image grid to the 9216th image grid each contain 100 pixels, and the color value matrix represents the average value of the R values, G values, and B values ​​of the 100 pixels in each image grid. The obtained color value matrix is:

[0101]

[0102] Furthermore, the method of calculating the first brightness matrix using a brightness conversion formula according to the color value matrix includes:

[0103] The first brightness matrix Y1 is calculated using the brightness conversion formula according to the color value matrix; the first brightness matrix is ​​expressed as:

[0104]

[0105] The brightness conversion formula is:

[0106]

[0107] Among them, Q u,l represents the element in the uth row and lth column of the first brightness matrix; Z max(u,l) Represents R u,l , G u,l , B u,l The maximum value of Z min(u,l) Represents R u,l , G u,l , B u,l The minimum value of .

[0108] Exemplarily, the first brightness matrix Y1 is calculated by using the brightness conversion formula according to the color value matrix:

[0109]

[0110] Furthermore, the method of calculating the optimal adjustment rate of display screen brightness by using a brightness adjustment optimization algorithm according to a preset upper limit brightness matrix, a preset lower limit brightness matrix, a first brightness matrix, and a first illumination includes:

[0111] A first objective function is constructed according to the upper limit brightness matrix, the lower limit brightness matrix, the first brightness matrix, and the first illumination; the first objective function is expressed as:

[0112]

[0113] Wherein, V1(α) represents the first objective function; the independent variable of the first objective function is α, α represents the brightness adjustment rate of the display screen; Y min Represents the lower limit brightness matrix; Y max represents the upper limit brightness matrix; H represents the first illuminance, in lux; k represents the preset perceived illuminance, in lux; T1 represents the first duty cycle; express The F-norm represents the total length of all elements of the matrix in the Euclidean space.

[0114] For example, the most comfortable brightness for human eyes is between 0.4 and 0.7, so the lower limit brightness matrix Y min All elements in take the value 0.4, and Y min It is a 72×128-order matrix. The upper limit brightness matrix Y max All elements in take the value 0.7, and Y max It is a 72×128-order matrix. The first illuminance H=347 lux, and the preset perceived illuminance k=500 lux. The components comprehensively reflect the synergistic effects of the display brightness adjustment rate and the ambient illumination on the user-perceived brightness. The F norm represents the total length of all elements of the matrix in the Euclidean space, that is, the square root of the sum of the squares of all elements in the matrix.

[0115] Construct the first constraint condition; the first constraint condition is:

[0116]

[0117] in, express The number of elements with negative values; express The number of elements in which the value is negative.

[0118] Taking the minimum value of the first objective function as the goal and the first constraint condition as the constraint condition, the particle swarm optimization algorithm is used to calculate the optimal value of α, which is recorded as the optimal adjustment rate of the display brightness α * .

[0119] Exemplarily, the optimal adjustment rate α of the display brightness is calculated * =-0.32.

[0120] Further, the method of obtaining the functional relationship between the display screen brightness adjustment rate and the display screen PWM dimming circuit duty cycle change rate, recorded as the first function, and calculating the optimal adjustment value of the display screen PWM dimming circuit duty cycle according to the display screen brightness optimal adjustment rate, the first function, and the first duty cycle, recorded as the second duty cycle, includes:

[0121] The functional relationship between the display screen brightness adjustment rate and the display screen PWM dimming circuit duty cycle change rate is obtained, which is recorded as a first function; the first function is expressed as:

[0122] α=f1(β)=β;

[0123] Wherein, f1(β) represents the first function; β represents the duty cycle change rate of the display screen PWM dimming circuit.

[0124] According to the optimal adjustment rate of the brightness of the display screen, the first function, and the first duty cycle, the optimal adjustment value of the duty cycle of the display screen PWM dimming circuit is calculated using the duty cycle adjustment formula, which is recorded as the second duty cycle; the duty cycle adjustment formula is:

[0125] T2=α * T1;

[0126] Wherein, T2 represents the second duty cycle.

[0127] For example, it is deduced that the display screen using LED backlight technology has a brightness adjustment rate that is equal to the duty cycle change rate of the display screen PWM dimming circuit. Therefore, the optimal adjustment value of the duty cycle of the display screen PWM dimming circuit can be calculated using the optimal brightness adjustment rate of the display screen, that is, the second duty cycle. * =-0.32, T1 = 0.8, so T2 = -0.256 is calculated.

[0128] Embodiment 2: Based on the same inventive concept, Figure 2 As shown, this embodiment also provides a display screen brightness correction system, the system comprising:

[0129] A data reading module is used to obtain first data, wherein the first data includes preset camera image pixels and a first duty cycle; the camera image pixels include camera image pixel height and camera image pixel width; the first duty cycle represents a duty cycle preset by a display screen PWM dimming circuit without correction.

[0130] The brightness calculation module is connected to the data reading module and is used to point the camera lens rigidly fixed on the surface of the display screen toward the display screen to capture an original image; use a cutout algorithm to extract the captured image of the display screen surface in the original image, which is recorded as a cutout image; use an image super-resolution reconstruction algorithm and a shape correction algorithm to restore the pixels of the cutout image to camera image pixels to obtain a first image; use an illuminance meter rigidly fixed on the surface of the display screen to measure the ambient illumination to obtain a first illumination; divide the first image into N image grids according to a preset number of horizontal divisions and a preset number of vertical divisions according to the camera image pixels, which are recorded as the first image grid to the Nth image grid; calculate the RGB color values ​​of the pixels in the N image grids, and aggregate them to obtain a color value matrix; and use a brightness conversion formula to calculate the first brightness matrix according to the color value matrix.

[0131] The optimization calculation module is connected to the brightness calculation module and is used to calculate the optimal adjustment rate of the brightness of the display screen by using the brightness adjustment optimization algorithm according to a preset upper limit brightness matrix, a preset lower limit brightness matrix, a first brightness matrix, and a first illumination; obtain the functional relationship between the brightness adjustment rate of the display screen and the duty cycle change rate of the PWM dimming circuit of the display screen, which is recorded as the first function, and calculate the optimal adjustment value of the duty cycle of the PWM dimming circuit of the display screen according to the optimal adjustment rate of the brightness of the display screen, the first function, and the first duty cycle, which is recorded as the second duty cycle; the first duty cycle is added to the second duty cycle to obtain a third duty cycle; the third duty cycle represents the optimal duty cycle of the PWM dimming circuit of the display screen after correction.

[0132] The correction module is connected to the optimization calculation module and is used to correct the duty cycle of the display screen PWM dimming circuit to a third duty cycle.

[0133] Furthermore, the brightness calculation module includes:

[0134] The pixel decomposition module is used to calculate the number of pixels M according to the pixel height and pixel width of the camera image; the calculation formula of the number of pixels is:

[0135] M = h1 × h2;

[0136] Where h1 represents the pixel height of the camera image, and h2 represents the pixel width of the camera image.

[0137] The color value matrix calculation module is connected to the pixel decomposition module and is used to decompose the first image into M pixels; calculate the RGB color values ​​of the M pixels using an image processing algorithm to obtain the R value, G value and B value of the M pixels; average the R value, G value and B value of the pixels falling into the first image grid to the Nth image grid to obtain a color value matrix; the color value matrix is ​​expressed as:

[0138]

[0139] Among them, S represents the color value matrix; R u,l represents the average value of the R value of the pixels in the u×lth image grid; G u,l represents the average value of the G value of the pixels in the u×lth image grid; B u,l Represents the average value of the B value of the pixel points in the u×l-th image grid; u is an integer variable with a value from 1 to d1; l is an integer variable with a value from 1 to d2; d1 is the number of horizontal divisions, and d2 is the number of vertical divisions.

[0140] Furthermore, the brightness calculation module also includes:

[0141] The first brightness matrix calculation module is used to calculate the first brightness matrix Y1 according to the color value matrix using the brightness conversion formula; the first brightness matrix is ​​expressed as:

[0142]

[0143] The brightness conversion formula is:

[0144]

[0145] Among them, Q u,l represents the element in the uth row and lth column of the first brightness matrix; Z max(u,l) Represents R u,l , G u,l , B u,l The maximum value of Z min(u,l) Represents R u,l , G u,l , B u,l The minimum value of .

[0146] Furthermore, the optimization calculation module includes:

[0147] The first objective function construction module is used to construct a first objective function according to the upper limit brightness matrix, the lower limit brightness matrix, the first brightness matrix, and the first illumination; the first objective function is expressed as:

[0148]

[0149] Wherein, V1(α) represents the first objective function; the independent variable of the first objective function is α, α represents the brightness adjustment rate of the display screen; Y min Represents the lower limit brightness matrix; Y max represents the upper limit brightness matrix; H represents the first illuminance, in lux; k represents the preset perceived illuminance, in lux; T1 represents the first duty cycle; express The F-norm represents the total length of all elements of the matrix in the Euclidean space.

[0150] The first constraint condition building module is connected to the first objective function building module and is used to construct a first constraint condition; the first constraint condition is:

[0151]

[0152] in, express The number of elements with negative values; express The number of elements in which the value is negative.

[0153] The particle swarm optimization calculation module is connected to the first constraint condition construction module, and is used to take the first objective function value as the minimum and the first constraint condition as the constraint condition, and use the particle swarm optimization algorithm to calculate the optimal value of α, which is recorded as the optimal adjustment rate of the display brightness α * .

[0154] Furthermore, the optimization calculation module also includes:

[0155] The first function building module is used to obtain the functional relationship between the display screen brightness adjustment rate and the display screen PWM dimming circuit duty cycle change rate, which is recorded as the first function; the first function is expressed as:

[0156] α=f1(β)=β;

[0157] Wherein, f1(β) represents the first function; β represents the duty cycle change rate of the display screen PWM dimming circuit.

[0158] The second duty cycle calculation module is connected to the first function construction module and is used to calculate the optimal adjustment value of the duty cycle of the display screen PWM dimming circuit according to the optimal adjustment rate of the display screen brightness, the first function, and the first duty cycle, and record it as the second duty cycle; the duty cycle adjustment formula is:

[0159] T2=α * T1;

[0160] Wherein, T2 represents the second duty cycle.

[0161] It should be noted that, regarding the system in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0162] Finally, it should be noted that: Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A display screen brightness correction method, characterized in that: The method comprises the following steps: S1, obtaining first data, wherein the first data includes preset camera image pixels and a first duty cycle; the camera image pixels include camera image pixel height and camera image pixel width; the first duty cycle represents a duty cycle preset by a display screen PWM dimming circuit without correction; S2, directing the camera lens rigidly fixed on the surface of the display screen toward the display screen to obtain an original image; using a cutout algorithm to extract the captured image of the display screen surface in the original image, recorded as a cutout image; using an image super-resolution reconstruction algorithm and a shape correction algorithm to restore the pixels of the cutout image to camera image pixels, to obtain a first image; using an illuminance meter rigidly fixed on the surface of the display screen to measure the ambient illuminance, to obtain a first illuminance; according to the camera image pixels, dividing the first image into N image grids according to a preset number of horizontal divisions and a preset number of vertical divisions, recorded as the first image grid to the Nth image grid; calculating the RGB color values ​​of the pixels in the N image grids, and aggregating them to obtain a color value matrix; using a brightness conversion formula to calculate a first brightness matrix according to the color value matrix; S3, according to the preset upper limit brightness matrix, the preset lower limit brightness matrix, the first brightness matrix, and the first illumination, the brightness adjustment optimization algorithm is used to calculate the optimal adjustment rate of the brightness of the display screen; the functional relationship between the brightness adjustment rate of the display screen and the duty cycle change rate of the PWM dimming circuit of the display screen is obtained, which is recorded as the first function, and the optimal adjustment value of the duty cycle of the PWM dimming circuit of the display screen is calculated according to the optimal adjustment rate of the brightness of the display screen, the first function, and the first duty cycle, which is recorded as the second duty cycle; the first duty cycle is added to the second duty cycle to obtain a third duty cycle; the third duty cycle represents the optimal duty cycle of the PWM dimming circuit of the display screen after correction; S4, correcting the duty cycle of the display screen PWM dimming circuit to a third duty cycle.

2. The display screen brightness correction method according to claim 1, characterized in that: The method of calculating the RGB color values ​​of pixels in N image grids and aggregating them to obtain a color value matrix includes: The number of pixels M is calculated according to the pixel height and pixel width of the camera image; the calculation formula of the number of pixels is: M = h1 × h2; Where h1 represents the pixel height of the camera image, and h2 represents the pixel width of the camera image; The first image is pixel-decomposed to obtain M pixel points; the RGB color values ​​of the M pixel points are calculated using an image processing algorithm to obtain the R value, G value and B value of the M pixel points; the R value, G value and B value of the pixel points falling into the first image grid to the Nth image grid are averaged to obtain a color value matrix; the color value matrix is ​​expressed as: Among them, S represents the color value matrix; R u,l represents the average value of the R value of the pixels in the u×lth image grid; G u,l represents the average value of the G value of the pixels in the u×lth image grid; B u,l Represents the average value of the B value of the pixel points in the u×l-th image grid; u is an integer variable with a value from 1 to d1; l is an integer variable with a value from 1 to d2; d1 is the number of horizontal divisions, and d2 is the number of vertical divisions.

3. The display screen brightness correction method according to claim 2, characterized in that: The method of calculating the first brightness matrix using a brightness conversion formula according to the color value matrix includes: The first brightness matrix Y1 is calculated using the brightness conversion formula according to the color value matrix; the first brightness matrix is ​​expressed as: The brightness conversion formula is: Among them, Q u,l represents the element in the uth row and lth column of the first brightness matrix; Z max(u,l) Represents R u,l , G u,l , B u,l The maximum value of Z min(u,l) Represents R u,l , G u,l , B u,l The minimum value of .

4. The display screen brightness correction method according to claim 3, characterized in that: The method of calculating the optimal adjustment rate of display screen brightness by using a brightness adjustment optimization algorithm according to a preset upper limit brightness matrix, a preset lower limit brightness matrix, a first brightness matrix, and a first illumination includes: A first objective function is constructed according to the upper limit brightness matrix, the lower limit brightness matrix, the first brightness matrix, and the first illumination; the first objective function is expressed as: Wherein, V1(α) represents the first objective function; the independent variable of the first objective function is α, α represents the brightness adjustment rate of the display screen; Y min Represents the lower limit brightness matrix; Y max represents the upper limit brightness matrix; H represents the first illuminance, in lux; k represents the preset perceived illuminance, in lux; T1 represents the first duty cycle; express The F-norm represents the total length of all elements of the matrix in the Euclidean space; Construct the first constraint condition; the first constraint condition is: in, Indicates Y1 The number of elements with negative values; r1 express The number of elements with negative values; Taking the minimum value of the first objective function as the goal and the first constraint condition as the constraint condition, the particle swarm optimization algorithm is used to calculate the optimal value of α, which is recorded as the optimal adjustment rate of the display brightness α * .

5. The display screen brightness correction method according to claim 4, characterized in that: The method of obtaining the functional relationship between the display screen brightness adjustment rate and the display screen PWM dimming circuit duty cycle change rate, recorded as the first function, and calculating the optimal adjustment value of the display screen PWM dimming circuit duty cycle according to the display screen brightness optimal adjustment rate, the first function, and the first duty cycle, recorded as the second duty cycle, includes: The functional relationship between the display screen brightness adjustment rate and the display screen PWM dimming circuit duty cycle change rate is obtained, which is recorded as a first function; the first function is expressed as: α＝f1(β)＝β； Wherein, f1(β) represents the first function; β represents the duty cycle change rate of the display PWM dimming circuit; According to the optimal adjustment rate of the brightness of the display screen, the first function, and the first duty cycle, the optimal adjustment value of the duty cycle of the display screen PWM dimming circuit is calculated using the duty cycle adjustment formula, which is recorded as the second duty cycle; the duty cycle adjustment formula is: T2=a * T1; Wherein, T2 represents the second duty cycle.

6. Display screen brightness correction system, characterized in that: The system comprises: A data reading module, used to obtain first data, wherein the first data includes preset camera image pixels and a first duty cycle; the camera image pixels include camera image pixel height and camera image pixel width; the first duty cycle represents a duty cycle preset by a display screen PWM dimming circuit without correction; The brightness calculation module is connected to the data reading module and is used to point the camera lens rigidly fixed on the surface of the display screen toward the display screen to capture an original image; use a cutout algorithm to extract the captured image of the display screen surface in the original image, which is recorded as a cutout image; use an image super-resolution reconstruction algorithm and a shape correction algorithm to restore the pixels of the cutout image to camera image pixels to obtain a first image; use an illuminance meter rigidly fixed on the surface of the display screen to measure the ambient illumination to obtain a first illumination; divide the first image into N image grids according to a preset number of horizontal and vertical divisions according to the camera image pixels, which are recorded as the first image grid to the Nth image grid; calculate the RGB color values ​​of the pixels in the N image grids, and aggregate them to obtain a color value matrix; use a brightness conversion formula to calculate the first brightness matrix according to the color value matrix; The optimization calculation module is connected to the brightness calculation module and is used to calculate the optimal adjustment rate of the brightness of the display screen by using the brightness adjustment optimization algorithm according to the preset upper limit brightness matrix, the preset lower limit brightness matrix, the first brightness matrix, and the first illumination; obtain the functional relationship between the brightness adjustment rate of the display screen and the duty cycle change rate of the PWM dimming circuit of the display screen, which is recorded as the first function, and calculate the optimal adjustment value of the duty cycle of the PWM dimming circuit of the display screen according to the optimal adjustment rate of the brightness of the display screen, the first function, and the first duty cycle, which is recorded as the second duty cycle; the first duty cycle is added to the second duty cycle to obtain a third duty cycle; the third duty cycle represents the optimal duty cycle of the PWM dimming circuit of the display screen after correction; The correction module is connected to the optimization calculation module and is used to correct the duty cycle of the display screen PWM dimming circuit to a third duty cycle.

7. The display screen brightness correction system according to claim 6, characterized in that: The brightness calculation module comprises: The pixel decomposition module is used to calculate the number of pixels M according to the pixel height and pixel width of the camera image; the calculation formula of the number of pixels is: M = h1 × h2; Where h1 represents the pixel height of the camera image, and h2 represents the pixel width of the camera image; The color value matrix calculation module is connected to the pixel decomposition module and is used to decompose the first image into M pixels; calculate the RGB color values ​​of the M pixels using an image processing algorithm to obtain the R value, G value and B value of the M pixels; average the R value, G value and B value of the pixels falling into the first image grid to the Nth image grid to obtain a color value matrix; the color value matrix is ​​expressed as: Among them, S represents the color value matrix; R u,l represents the average value of the R value of the pixels in the u×lth image grid; G u,l represents the average value of the G value of the pixels in the u×lth image grid; B u,l Represents the average value of the B value of the pixel points in the u×l-th image grid; u is an integer variable with a value from 1 to d1; l is an integer variable with a value from 1 to d2; d1 is the number of horizontal divisions, and d2 is the number of vertical divisions.

8. The display screen brightness correction system according to claim 7, characterized in that: The brightness calculation module also includes: The first brightness matrix calculation module is used to calculate the first brightness matrix Y1 according to the color value matrix using the brightness conversion formula; the first brightness matrix is ​​expressed as: The brightness conversion formula is: Among them, Q u,l represents the element in the uth row and lth column of the first brightness matrix; Z max(u,l) Represents R u,l , G u,l , B u,l The maximum value of Z min(u,l) Represents R u,l , G u,l , B u,l The minimum value of .

9. The display screen brightness correction system according to claim 8, characterized in that: The optimization calculation module comprises: The first objective function construction module is used to construct a first objective function according to the upper limit brightness matrix, the lower limit brightness matrix, the first brightness matrix, and the first illumination; the first objective function is expressed as: Wherein, V1(α) represents the first objective function; the independent variable of the first objective function is α, α represents the brightness adjustment rate of the display screen; Y min Represents the lower limit brightness matrix; Y max represents the upper limit brightness matrix; H represents the first illuminance, in lux; k represents the preset perceived illuminance, in lux; T1 represents the first duty cycle; express The F-norm represents the total length of all elements of the matrix in the Euclidean space; The first constraint condition building module is connected to the first objective function building module and is used to construct a first constraint condition; the first constraint condition is: in, express The number of elements with negative values; express The number of elements with negative values; The particle swarm optimization calculation module is connected to the first constraint condition construction module, and is used to take the first objective function value as the minimum and the first constraint condition as the constraint condition, and use the particle swarm optimization algorithm to calculate the optimal value of α, which is recorded as the optimal adjustment rate of the display brightness α * .

10. The display screen brightness correction system according to claim 9, characterized in that: The optimization calculation module also includes: The first function building module is used to obtain the functional relationship between the display screen brightness adjustment rate and the display screen PWM dimming circuit duty cycle change rate, which is recorded as the first function; the first function is expressed as: α＝f1(β)＝β； Wherein, f1(β) represents the first function; β represents the duty cycle change rate of the display PWM dimming circuit; The second duty cycle calculation module is connected to the first function construction module and is used to calculate the optimal adjustment value of the duty cycle of the display screen PWM dimming circuit according to the optimal adjustment rate of the display screen brightness, the first function, and the first duty cycle, and record it as the second duty cycle; the duty cycle adjustment formula is: T2=a * T1; Wherein, T2 represents the second duty cycle.

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