Backlight diffusion parameter generation method, display control method and device, and display device
By generating backlight diffusion parameters and using point spread function modeling and compensation data calculation, the problem of inaccurate brightness diffusion in local dynamic dimming is solved, and the display effect and power consumption efficiency are improved.
Patent Information
- Application Number
- CN202380008439.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-03-24
- Publication Date
- 2025-10-10
- Estimated Expiration
- 2043-03-24
AI Technical Summary
In local dynamic dimming technology, existing technologies fail to accurately model the brightness diffusion of the luminous area, resulting in unsatisfactory display effects, affecting picture quality contrast and power consumption.
By generating backlight diffusion parameters, the backlight diffusion is modeled using a point spread function, the equivalent backlight brightness of each pixel is calculated, and image display is performed based on the compensation data, including selecting illumination diffusion data, preprocessing, function fitting, and storing a backlight diffusion parameter lookup table.
It achieves more accurate compensation data calculation, improves the quality of the display image, reduces backlight power consumption, and improves image contrast and video frame rate.
Smart Images

Figure CN119256351B_ABST
Abstract
Description
Technical Field
[0001] The embodiments of the present disclosure relate to, but are not limited to, the field of display technology, and in particular to a backlight diffusion parameter generation method, a display control method and device, and a display device. Background Art
[0002] Liquid Crystal Display (LCD) devices require a backlight module to provide light to the display panel. In recent years, with the enhancement of controller computing power and technological advancement, local dynamic dimming has been widely used in the field of high-quality display. Figure 1A As shown, local dynamic dimming achieves the same display effect as full-brightness backlighting by dimming the backlight in darker areas of the displayed image and compensating the LCD display signal accordingly in the display control. Local dynamic dimming can effectively reduce overall device power consumption and improve image quality and contrast, which is particularly important for mobile devices and ultra-large display devices. Summary of the Invention
[0003] The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.
[0004] The present disclosure provides a method for generating backlight diffusion parameters for a display device including a backlight module and a display panel, wherein the backlight module includes a light-emitting panel and an optical film group located between the light-emitting panel and the display panel; wherein the light-emitting panel includes a plurality of light-emitting areas, and the display panel includes a plurality of pixels; the method for generating backlight diffusion parameters includes:
[0005] selecting and measuring light spread data of at least one of the plurality of light-emitting areas, wherein the light spread data includes brightness data of a plurality of pixels on a display panel when only one of the light-emitting areas is illuminated, and distance data between positions corresponding to the plurality of pixels and a position of the illuminated light-emitting area;
[0006] Preprocessing the light diffusion data to obtain effective pixels;
[0007] Performing function fitting based on the data corresponding to the plurality of effective pixels to obtain a point spread function representing the relationship between diffusion brightness and diffusion distance;
[0008] A backlight diffusion parameter lookup table is stored, wherein the backlight diffusion parameter lookup table includes multiple diffusion distance binding points and the diffusion brightness corresponding to each of the diffusion distance binding points, and also includes a diffusion slope between two adjacent diffusion distance binding points, wherein the diffusion slope is used to interpolate and calculate the diffusion brightness corresponding to the diffusion distance between the two diffusion distance binding points.
[0009] Optionally, the preprocessing of the light diffusion data comprises:
[0010] The light diffusion data is truncated, and the truncated data is normalized.
[0011] Optionally, the obtained point spread function is a function model of at least one of:
[0012] a Gaussian function model:
[0013] a sine function model:
[0014] a Fourier function model:
[0015] wherein n is an order, a n , b n , c n , and w are coefficients, x is a backlight diffusion distance, and f(x) is a diffusion luminance.
[0016] Optionally, the stored backlight diffusion parameter lookup table is calculated by the following method:
[0017] The point spread function is subjected to inverse first-order derivation and second-order derivation.
[0018] One or more first numerical ranges are selected, the maximum value of the second-order derivative in each first numerical range is less than a preset second-order derivative threshold value, and the difference between the maximum value and the minimum value of the second-order derivative in each first numerical range is less than a preset second-order derivative difference threshold value.
[0019] The diffusion distance corresponding to each end of each first numerical range is taken as two diffusion distance binding points, and the inverse first-order derivative value corresponding to one second-order derivative value in each first numerical range is taken as a diffusion slope between the two diffusion distance binding points.
[0020] Optionally, the inverse first-order derivative value corresponding to one second-order derivative value in each first numerical range is taken as a diffusion slope between the two diffusion distance binding points, comprising:
[0021] The inverse first-order derivative value corresponding to the maximum value of the second-order derivative in each first numerical range is taken as a diffusion slope between the two diffusion distance binding points.
[0022] Optionally, the interval between two adjacent diffusion distance binding points is 2k diffusion distances, and k is a natural number greater than 0.
[0023] The display control method comprises:
[0024] set the set backlight brightness of each light emitting area according to the gray scale of the image to be displayed;
[0025] obtain the backlight diffusion parameter of the backlight module of the display device, wherein the backlight diffusion parameter of the backlight module is obtained in advance according to the backlight diffusion parameter generation method as described in any of the embodiments of the present disclosure and stored in the display device;
[0026] calculate the equivalent backlight brightness of each pixel according to the set backlight brightness of each light emitting area and the backlight diffusion parameter;
[0027] calculate the corresponding compensation data according to the equivalent backlight brightness of each pixel;
[0028] control the backlight module to set the backlight brightness to light up the light emitting area, and control the display panel to display the image according to the compensation data.
[0029] The embodiments of the present disclosure further provide a display control device, comprising a memory and a processor connected to the memory, the memory is used to store instructions, and the processor is configured to execute the steps of the display control method according to any of the embodiments of the present disclosure based on the instructions stored in the memory.
[0030] The embodiments of the present disclosure further provide a display device, comprising the display control device according to any of the embodiments of the present disclosure, a display panel and a backlight module.
[0031] The embodiments of the present disclosure further provide a computer readable storage medium, which stores a computer program, and the program is executed by a processor to implement the display control method according to any of the embodiments of the present disclosure.
[0032] Other aspects can be apparent to those of ordinary skill in the art after a reading of the attached drawings and detailed description. BRIEF DESCRIPTION OF DRAWINGS
[0033] The accompanying drawings are included to provide a further understanding of the technical solutions of the present disclosure, and constitute a part of the specification, and are used together with the embodiments of the present disclosure to explain the technical solutions of the present disclosure, and do not constitute a limitation on the technical solutions of the present disclosure. The shapes and sizes of the components in the drawings do not reflect the true proportions, and the purpose is only to schematically illustrate the present disclosure.
[0034] Figure 1A It is a schematic diagram of the principle of the local dynamic dimming technology;
[0035] Figure 1B It is a schematic diagram of the light emitting range of a single light emitting area without modulation by the optical film set;
[0036] Figure 1CA schematic diagram of the diffusion range after modulation by the optical film group when a single light-emitting area includes 2*2 Mini LEDs;
[0037] Figure 1D A schematic diagram of another diffusion range after modulation by the optical film group when a single light-emitting area includes 2*2 Mini LEDs;
[0038] Figure 1E A schematic diagram of the diffusion range after modulation by the optical film group when a single light-emitting area includes 3*2 Mini LEDs;
[0039] Figure 1F A schematic diagram of the diffusion range after modulation by the optical film group when a single light-emitting area includes 2*1 Mini LEDs;
[0040] Figure 2 Schematic diagram of display control principle according to an embodiment of the present disclosure;
[0041] Figure 3 1 is a flow chart of a method for generating backlight diffusion parameters according to an embodiment of the present disclosure;
[0042] Figure 4A A schematic diagram of a software interface for acquiring brightness data by a brightness acquisition device according to an embodiment of the present disclosure;
[0043] Figure 4B Schematic diagram of comparison between untruncated data and truncated data according to one embodiment of the present disclosure;
[0044] Figure 5 Schematic diagram of the diffusion range of a single light-emitting area according to an embodiment of the present disclosure;
[0045] Figure 6 Schematic diagram of curve fitting results of three function models according to an embodiment of the present disclosure;
[0046] Figure 7 Schematic diagram of Gaussian function model and its first-order derivative and second-order derivative;
[0047] Figure 8 A flowchart of a display control method provided by an exemplary embodiment of the present disclosure;
[0048] Figure 9 A schematic structural diagram of a display control device provided by an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION
[0049] To make the objectives, technical solutions and advantages of the present disclosure more clearly understood, the embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. It should be noted that, unless there is a conflict, the embodiments and features in the embodiments of the present disclosure can be combined with each other in any manner.
[0050] Unless otherwise defined, the technical or scientific terms used in the embodiments of the present disclosure should have the ordinary meaning understood by people with ordinary skills in the field to which the present disclosure belongs. The words "first", "second" and similar words used in the embodiments of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. The words "include" or "comprising" and similar words mean that the elements or objects preceding the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.
[0051] Mini-LED (Mini-Light Emitting Diode) technology refers to inorganic light-emitting diodes with a light-emitting chip area of 100-200μm. Mini LED inherits the high efficiency, high brightness, high reliability, and fast response time of inorganic LEDs. It also features self-luminescence, eliminating the need for light-emitting components. This makes it more energy-efficient, simpler, smaller, and thinner. It also boasts a longer lifetime, higher brightness, better material stability, and no image burn-in. Its application in LCD displays enables multi-zone dimming, reducing backlight power consumption and improving image contrast by adjusting the brightness of each zone.
[0052] The display device includes a backlight module and a display panel. The backlight module includes a light-emitting plate and an optical film group located between the light-emitting plate and the display panel. The light-emitting plate includes multiple light-emitting areas, and the optical film group includes at least a prism, a diffuser, a polarizer, etc. In related technologies, when the display device displays an image, the brightness required to be provided by each light-emitting area is first set according to the grayscale of the displayed image. Each pixel in the display panel then controls the rotation angle of the liquid crystal molecules in the area where the pixel is located according to the obtained brightness. Figures 1B to 1F As shown, the light emitting board 100 is arranged opposite to the display panel, and the sizes of the surfaces facing each other are similar. The light emitting board can be divided into a number of light emitting areas 111, for example, an array of M*N light emitting areas, where M and N are not more than 10. 2 The pixel resolution of the display panel is W*H, that is, W*H pixels are arranged in an array, and both W and H are at least 10 3 Therefore, the resolution of the light-emitting area is generally much smaller than the pixel resolution of the display panel.
[0053] Each light-emitting area 111 includes at least one light-emitting element 110, which can be implemented by Mini LED or any other light-emitting device. Each light-emitting element can be equivalent to a point light source or a cosine light source. If a single light-emitting area includes only one Mini LED, such as Figure 1B As shown in (1), the light emitting range 200' of the light emitting area that has not been modulated by the optical film group is basically circular; if a single light emitting area includes 2*2 Mini LEDs, such as Figure 1B As shown in (2), the light emitting range 200' of the light emitting area that has not been modulated by the optical film group is similar to the shape of petals. However, the light emitted by the light emitting area needs to be modulated by the optical film group before entering the multiple pixels of the display panel, that is, the light emitting range 200' of the light emitting area will be modulated into a diffusion range 200. The diffusion range of the light emitting area is affected by many factors such as the size of the light emitting element, the light emitting angle of the light emitting element, the arrangement position of the light emitting element in the light emitting area, and the characteristics of each optical film material in the optical film group. However, for a certain model of display device, once the model of the light emitting element, the arrangement position, the material and characteristics of the optical film group, etc. are determined, the same function can be used to describe the characteristics of the backlight in the display device of the same model.
[0054] In the case where a plurality of light-emitting elements of the same model are provided in each light-emitting area and all the light-emitting elements are arranged in a centrally symmetrical manner, the contour shape of the diffusion range 200 obtained after the light emitted from a single light-emitting area is modulated by the optical film group can be, for example, Figure 1C A circle with radius r as shown, or Figure 1D The rounded rectangle shown. Figure 1B and 1C In the embodiment, each light-emitting area includes light-emitting elements 110 arranged in a 2*2 array. When multiple light-emitting elements of the same model are provided in each light-emitting area, and all light-emitting elements are arranged in an axisymmetric rather than a centrally symmetrical manner, the contour shape of the diffusion range 200 obtained by modulating the light emitted by a single light-emitting area through the optical film group can be, for example, Figure 1E The shape shown, or as Figure 1F The ellipse shown. Figure 1E In the embodiment, each light emitting area includes light emitting elements 110 arranged in a 3*2 array; Figure 1F In the embodiment, each light emitting area includes light emitting elements 110 arranged in a 2*1 array.
[0055] The shapes of the diffusion ranges in the above figures are merely for the purpose of illustrating the principles of the embodiments of the present disclosure and are not intended to limit the diffusion range of the light-emitting area. Those skilled in the art can, under the guidance of this disclosure, obtain and calculate the point spread function of a light-emitting area having an elliptical or other shape without exceeding the scope of this disclosure.
[0056] The light intensity of a single light emitting element decays with the increase of diffusion distance, and the degree of decay is isotropic. Similarly, the light intensity of a single light emitting region also decays with the increase of diffusion distance. From the physical position relationship, the area where a light emitting region is located corresponds to the areas where a plurality of pixels are located, and therefore the backlight brightness received by different pixels corresponding to the same subregion is different. Considering that the light emitted by the light emitting region is modulated by the optical film group and has a diffusion range, a same pixel is affected by the light emitted by different light emitting regions.
[0057] Figure 2 FIG. 1 is a schematic diagram of a display control principle of local dynamic dimming according to an embodiment of the present disclosure. When local dynamic dimming is performed, the display control device 400 receives an image to be displayed, and generates a backlight control signal and a display panel control signal respectively. The backlight control signal can be generated according to the gray scale distribution characteristics of the image to be displayed, so as to control different light emitting regions to present different brightness. When the backlight brightness of a local region is changed, the corresponding compensation data is input into the display panel control signal, so as to accurately realize the target display effect. This compensation process needs to consider the change of the backlight brightness of each pixel relative to the static high-brightness backlight after the backlight is changed.
[0058] The backlight obtained by each pixel not only comes from the light emitting region at the position directly opposite to the pixel, but also comes from the adjacent light emitting regions. The brightness diffusion of each light emitting region presents very complex nonlinear characteristics. If the backlight diffusion parameters cannot be accurately modeled and the influence of the surrounding light emitting regions on the brightness is ignored, appropriate compensation data cannot be obtained, which directly affects the quality of the final display picture. This is one of the main reasons why the dynamic dimming display effect is not ideal in the related art. To solve this problem, an embodiment of the present disclosure proposes a method for generating backlight diffusion parameters. The method models the backlight diffusion parameters by using a point spread function and solves the model parameters through a backlight lighting experiment. On this basis, the equivalent backlight brightness of W*H pixels after diffusion is calculated according to the backlight diffusion parameters of M*N subregions, and compensation data is obtained accordingly.
[0059] In an embodiment of the present disclosure, the compensation data refers to the gray scale value of each pixel of the display panel after compensation. In some exemplary embodiments, the gray scale value of each pixel after compensation can be determined in the following manner:
[0060] The compensation rate of each pixel on the display panel is calculated, and the compensation rate S=(Lmax / Lnew)^(1 / gamma), where Lmax is the original backlight brightness value of the pixel, Lnew is the equivalent backlight brightness value of the pixel calculated, gamma is the gamma value of the display panel, and ^ is the power index operation.
[0061] The compensated grayscale value of each pixel is determined, where the compensated grayscale value Gnew=Gori*S, wherein Gori is the original grayscale value of the pixel.
[0062] In this disclosure, backlight diffusion parameters include parameters used to describe the diffusion range of a light-emitting area. For example, the backlight diffusion parameters may include the diffusion brightness corresponding to different diffusion distances when only one light-emitting area is illuminated. Furthermore, the backlight diffusion parameters may also include, for a single pixel, all A*B effective light-emitting areas that affect the brightness of the pixel, as well as the diffusion weight data corresponding to each effective light-emitting area. In this disclosure, the effective light-emitting area of a pixel refers to all light-emitting areas that affect the brightness of the pixel.
[0063] The change in brightness of the luminous area with the diffusion distance can be described by a point spread function (PSF). In an optical system, a point spread function can be used to describe the light field distribution of the output image when the input object is a point light source. The method proposed in the present disclosure calculates the backlight diffusion weight based on the diffusion distance to simulate the diffusion of the luminous area. By lighting a single luminous area multiple times and processing the display panel data, the diffusion range of a luminous area is obtained, and the diffusion weights corresponding to different distances from the center of the luminous area are accurately obtained. Therefore, in the subsequent display control, the equivalent backlight brightness corresponding to each pixel can be calculated based on the diffusion weight, and then accurate compensation data can be obtained based on the brightness equivalence relationship.
[0064] The method and apparatus of the embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.
[0065] Figure 3 It is a flowchart of a method for generating backlight diffusion parameters according to an embodiment of the present disclosure.
[0066] The backlight diffusion parameter generation method is used for a display device including a backlight module and a display panel, wherein the backlight module includes a light-emitting panel and an optical film group located between the light-emitting panel and the display panel; wherein the light-emitting panel includes multiple light-emitting areas, and the display panel includes multiple pixels. The backlight diffusion parameter generation method includes:
[0067] Step 110: Select and measure light spread data of at least one of the plurality of light-emitting areas, wherein the light spread data includes brightness data of a plurality of pixels on the display panel when only one light-emitting area is illuminated, and distance data between positions corresponding to the plurality of pixels and a position of the illuminated light-emitting area;
[0068] Step 120: pre-process the light diffusion data to obtain effective pixels;
[0069] Step 130: Perform function fitting based on the data corresponding to the multiple valid pixels to obtain a point spread function that represents the relationship between the diffusion brightness y and the diffusion distance x;
[0070] Step 140: store a backlight diffusion parameter lookup table, which includes multiple diffusion distance binding points and the diffusion brightness corresponding to each diffusion distance binding point, and also includes a diffusion slope between two adjacent diffusion distance binding points. The diffusion slope is used to interpolate and calculate the diffusion brightness corresponding to the diffusion distance between the two diffusion distance binding points.
[0071] In an embodiment of the present disclosure, when a certain light-emitting area is illuminated and brightness data of multiple pixels on the display panel is collected, it is necessary to control the deflection degree of the liquid crystal at the position corresponding to each pixel on the display panel to be the same. For example, the liquid crystal box in the display panel can allow all light emitted by a single light-emitting area and adjusted by the optical film group to pass through; when describing the distance data between the positions corresponding to multiple pixels and the position of the illuminated light-emitting area, the distance between the orthographic projection of the position of the pixel center on the display panel and the orthographic projection of the position of the light-emitting area center on the display panel can be used as the distance between the position corresponding to the pixel and the position of the light-emitting area.
[0072] In the embodiment of the present disclosure, when a light-emitting area is individually illuminated, pixels falling within the diffusion range of the light-emitting area are referred to as effective pixels corresponding to the light-emitting area.
[0073] In the disclosed embodiment, the diffusion distance binding point refers to the diffusion distance pre-selected on the point spread function curve obtained in step 130, for which the corresponding diffusion brightness needs to be stored. The diffusion slope between two adjacent diffusion distance binding points refers to the slope of the line connecting the two adjacent diffusion distance binding points on the point spread function curve obtained in step 130. The diffusion brightness corresponding to a non-diffusion distance binding point is calculated by linearly interpolating the diffusion brightness corresponding to the two diffusion distance binding points adjacent to the non-diffusion distance binding point and the diffusion slope between the two adjacent diffusion distance binding points.
[0074] The backlight diffusion parameter generation method of the disclosed embodiment greatly reduces the amount of diffusion distance and diffusion brightness data that needs to be stored by storing multiple diffusion distance binding points, the diffusion brightness corresponding to each diffusion distance binding point, and the diffusion slope between two adjacent diffusion distance binding points in a backlight diffusion parameter lookup table. The diffusion brightness corresponding to the diffusion distance between two diffusion distance binding points can be obtained through linear interpolation calculation without the need for complex calculations, thereby reducing the program calculation overhead while also reducing the hardware's demand for storage.
[0075] In some exemplary embodiments, in step 110, multiple light-emitting zones in different regions of the display device may be selected, and light spread data for each light-emitting zone may be measured. The light spread data includes brightness data for multiple pixels on the display panel when each light-emitting zone is individually illuminated, and distance data between the position corresponding to each pixel and the position of the illuminated light-emitting zone. The position corresponding to the pixel may be described by the coordinate position of the pixel on the display panel, and the position of the light-emitting zone may be described by the coordinate position corresponding to the orthographic projection of the geometric center of the light-emitting zone on the display panel.
[0076] The brightness measurement can be achieved using a variety of brightness measurement devices, for example, the two-dimensional color analyzer CA-S25w can be used. Figure 4A This is a schematic diagram of the software interface for acquiring brightness data using the CA-S25w 2D color analyzer, according to one embodiment of the present disclosure. By photographing the light-emitting surface of a display panel, the maximum diffusion distance and diffusion intensity (i.e., the change in diffuse brightness with diffusion distance) of a single luminous area can be determined based on the photographic results. When measuring light diffusion data, the display panel's liquid crystal cell must be controlled to ensure that all light emitted from a single luminous area and regulated by the optical film assembly passes through.
[0077] like Figure 4A As shown, under normal circumstances, the diffusion law of the light emitted by a single MiniLED is the same in all directions. When any direction is selected, the light intensity of a single MiniLED is approximately a two-dimensional Gaussian distribution. Therefore, in some exemplary embodiments, one-dimensional diffusion laws in two directions parallel to the plane of the display panel and perpendicular to each other can be obtained for analysis, and then the two-dimensional diffusion law of a single MiniLED in the plane parallel to the display panel can be obtained by superposition.
[0078] In order to make the obtained data better reflect the overall situation of each position of the display panel, in some embodiments, the selected multiple light-emitting areas may include the light-emitting areas located in the middle, upper left, upper right, lower left, and lower right positions of the display device. For example, the light-emitting areas at the above-mentioned specific positions can be selected for measurement. Obviously, other positions or multiple light-emitting areas of different numbers can also be selected for measurement. The more light-emitting areas are measured, the more comprehensive the diffusion range of the light-emitting areas at different positions can be reflected; accordingly, the number of experiments required and the amount of data processing calculations will also increase. Therefore, it is possible to flexibly select according to actual needs, and even light up all light-emitting areas one by one for measurement.
[0079] When describing the diffusion distance, it can be described based on the distance between the position corresponding to the pixel and the location of the luminous area. (When calculating the distance between the position corresponding to the pixel and the location of the luminous area, the distance between the orthographic projection of the pixel center position on the display panel and the orthographic projection of the luminous area center position on the display panel can be used as the distance between the position corresponding to the pixel and the location of the luminous area.) Furthermore, when describing the diffusion distance, the distance between the centers of two adjacent pixels can be used as a unit length. For example, a diffusion distance of 5 indicates that the distance between the position corresponding to the pixel center and the location of the luminous area center is 5 unit lengths. Therefore, when collecting light diffusion data for the positions corresponding to the pixels, to facilitate calculation of the distance data between the position corresponding to the pixel and the location of the illuminated luminous area, pixels whose distances from the corresponding positions to the location of the illuminated luminous area are integers can be selected for data collection. For example, when individually illuminating a luminous area, the brightness data of multiple pixels on the display panel and the distance data between the positions corresponding to the multiple pixels and the location of the illuminated luminous area may include diffuse brightness and diffusion distance data for multiple pixels located at multiple different distances in the horizontal and vertical directions from the location of the illuminated luminous area. Of course, it is also possible to select pixels at other positions, for example, every pixel in both the horizontal and vertical directions, or a certain number of pixels at intervals.
[0080] The present disclosure uses the light-emitting range of the light-emitting element after passing through the optical film group for modeling, which can enable each pixel to obtain a more accurate equivalent backlight brightness value, thereby making the compensation data more reasonable, avoiding the loss of details on the image, and improving the visual effect.
[0081] In some exemplary embodiments, in step 120, pre-processing the light diffusion data may include:
[0082] Normalize the light diffusion data.
[0083] Since different test instruments have different sensitivities to minimum brightness, normalizing the light diffusion data can eliminate the impact of different test instruments on the test results. After normalization, the diffusion brightness corresponding to each diffusion distance can also be called the backlight diffusion weight.
[0084] In some exemplary embodiments, in step 120, pre-processing the light diffusion data may include:
[0085] Correct abnormal data points.
[0086] Abnormal data points can be detected based on pre-set anomaly detection criteria. For example, a data point that experiences a sudden change in diffusion brightness as diffusion distance increases can be considered an abnormal data point. By correcting abnormal data points, the impact of abnormal data points caused by stains, dust, etc. on the test results can be eliminated.
[0087] According to the principle of light diffusion, the brightness of the light emitting area is inversely correlated with the diffusion distance, and as the diffusion distance increases, the change trend of the diffusion brightness tends to be gentle, so it is inevitable that lower diffusion brightness corresponds to longer diffusion distance, such as Figure 4B As shown, the horizontal axis is the normalized diffusion distance (the distance between the centers of two adjacent pixels is a unit length), and the vertical axis is the normalized diffusion brightness (dimensionless).
[0088] In some exemplary embodiments, in step 120, pre-processing the light diffusion data may include:
[0089] The light diffusion data is truncated and normalized.
[0090] Hardware processors, such as Field-Programmable Gate Array (FPGA), Digital Signal Processor (DSP), and Programmable Logic Array (PLA), excel at simple logical operations, while weight indexing and loop traversal greatly increase computational difficulty and hardware cost. Therefore, performing data truncation reduces storage media overhead and hardware computing media overhead, thereby improving the computational efficiency of the backlight diffusion module and saving hardware resource consumption.
[0091] During the truncation process, the diffusion range of the luminous area can be obtained, and the pixels within this diffusion range are valid pixels. The diffusion range can be light diffusion data with a diffusion brightness within a preset brightness threshold range. For example, the preset brightness threshold can be between 95% and 99% of the brightness at the center of the luminous area. For example, when the preset brightness threshold is 95% of the brightness at the center of the luminous area, the light diffusion data below 5% of the brightness at the center of the luminous area is truncated; when the preset brightness threshold is 97% of the brightness at the center of the luminous area, the light diffusion data below 3% of the brightness at the center of the luminous area is truncated; and when the preset brightness threshold is 99% of the brightness at the center of the luminous area, the light diffusion data below 1% of the brightness at the center of the luminous area is truncated. As the distance from the light source increases, the diffusion brightness will decay accordingly. After decaying to a certain extent, the impact on the total brightness will be negligible. To reduce the amount of calculation, the data with a diffusion brightness decaying below the preset brightness threshold range can be removed to obtain the diffusion range of a single luminous area. In addition, the relative error of brightness measurement will increase for data with too low brightness or far away from the light source. If these data are used for subsequent function fitting, the fitting results will be very inaccurate and cause large errors.
[0092] See also Figure 5 , Figure 5 This is a schematic diagram of the diffusion range of a single light-emitting zone according to an embodiment of the present disclosure. Here, the diffusion range 200 of light-emitting zone 111' affects seven light-emitting zones 111 in the horizontal direction and five light-emitting zones 111 in the vertical direction. In this embodiment, the diffusion range of each light-emitting zone varies in different directions, meaning that a light-emitting zone can cover different numbers of light-emitting zones in different directions.
[0093] In step 130, the brightness y of the pixel is set as the diffusion brightness, the distance x between the position corresponding to the pixel and the position of the illuminated luminous area is set as the diffusion distance, and a point diffusion function y=f(x) is established to characterize the relationship between the diffusion brightness y and the diffusion distance x.
[0094] In some exemplary embodiments, in step 130, the point spread function obtained is a function model of at least one of the following:
[0095] Gaussian function model:
[0096] Sine function model:
[0097] Fourier function model:
[0098] Among them, n is the order, a n 、b n 、c nw is a coefficient, x is a diffusion distance, and f(x) is a diffusion luminance.
[0099] The present disclosure establishes three point diffusion models, namely a Gaussian function model, a sine function model, and a Fourier function model. The three function models and their corresponding fitting formulas can obtain a small enough fitting error and are closer to the actual light diffusion of the light-emitting element. By proposing the three point diffusion models, the actual diffusion law is matched with the theoretical model, so that the backlight diffusion calculation is more accurate, and the risk of detail loss in liquid crystal display is reduced.
[0100] In some example embodiments, by performing function fitting according to the data corresponding to each valid pixel, each parameter in the point diffusion function can be obtained, and the obtained point diffusion function can be used as a backlight diffusion parameter.
[0101] In some example embodiments, in order to obtain more accurate results, performing function fitting according to the data of each valid pixel to obtain each parameter in the point diffusion function can include:
[0102] Statistically analyzing the data of each valid pixel to obtain the average value of the diffusion luminance corresponding to each diffusion distance as the average diffusion luminance of the diffusion distance;
[0103] According to the relationship data of the corresponding diffusion distance and the average diffusion luminance, function fitting is performed to obtain each parameter in the point diffusion function.
[0104] In one embodiment, five specific positions of the light-emitting area can be selected, and the data of the luminance change with distance in the horizontal and vertical directions of each light-emitting area can be collected, and then a total of 10 groups of light diffusion data can be obtained. In theory, the diffusion of the light-emitting area is isotropic in each direction of the two-dimensional plane, and the analysis of the experimental data also shows that the relationship between the diffusion luminance and the distance in the horizontal and vertical directions is basically the same. Therefore, 5 groups of data in one direction can be selected as the analysis data. To eliminate random errors, the average value of the 5 groups of analysis data can be obtained, and the average diffusion luminance corresponding to each diffusion distance can be obtained as the fitting data. By performing curve fitting of y=f(x) according to the fitting data, the corresponding point diffusion function can be obtained. Although the light is theoretically smooth diffusion, the interference of the equipment and external light during the measurement can cause certain interference to the measurement data, and the data has certain fluctuations. Some algorithms in related technologies can be used for curve fitting, or tool software can be directly used for data processing, for example, matlab, mathematica and other software can be used to realize function fitting. For example, Figure 6As shown, the horizontal axis is the diffusion distance after normalization (the distance between the centers of two adjacent pixels is a unit length), and the vertical axis is the difference in diffusion brightness after normalization. Each curve represents the difference function of two point spread functions obtained by function fitting using two of the three function models mentioned above. For example, curve 1 represents the difference function obtained by subtracting the point spread function obtained by function fitting using the Gaussian function model from the point spread function obtained by function fitting using the Fourier function model. Curve 2 represents the difference function obtained by subtracting the point spread function obtained by function fitting using the sine function model from the point spread function obtained by function fitting using the Fourier function model. Curve 3 represents the difference function obtained by subtracting the point spread function obtained by function fitting using the sine function model from the point spread function obtained by function fitting using the Gaussian function model.
[0105] The error comparisons obtained by different fitting methods are shown in Table 1. Figure 6 It can be seen that the differences between the point spread functions obtained by function fitting through the above-mentioned three function models are very small. The three function models provided in the embodiments of the present disclosure can all fit the characteristics of the data relatively reasonably, and the fitting results are more consistent with the data diffusion law between the diffusion distance and the diffusion brightness.
[0106] Sum of Squared Errors Fourier fitting 0.0003346 Gaussian fitting 0.0003442 Sine Fitting 0.0003522
[0107] Table 1
[0108] In some exemplary embodiments, in step 140, the stored backlight diffusion parameter lookup table is calculated as follows:
[0109] Take the inverse first-order and second-order derivatives of the point spread function;
[0110] Selecting one or more first numerical ranges, wherein the maximum value of the second-order derivative within each first numerical range is less than a preset second-order derivative threshold, and the difference between the maximum value and the minimum value of the second-order derivative within each first numerical range is less than a preset second-order derivative difference threshold;
[0111] The diffusion distances corresponding to both ends of each first numerical range are used as two diffusion distance binding points, and the inverse first-order derivative value corresponding to a second-order derivative value in each first numerical range is used as the diffusion slope between the two diffusion distance binding points.
[0112] The present disclosure provides a theoretical basis for a method of performing data interpolation by setting diffusion distance binding points through the application of multi-order derivatives of a function model, and the diffusion distance binding points set are more reasonable. Mathematically, when the second-order derivative of the original function within a certain numerical range is equal to zero, it means that the rate of change of the first-order derivative of the original function within the numerical range is zero, and the first-order derivative is a constant, that is, the original function is linear and monotonic within the numerical range. For example, the original function may be y=2x+5, etc. within the numerical range. In the embodiment of the present disclosure, the second-order derivative threshold can be set to a number very close to 0, and the second-order derivative difference threshold can also be set to a number very close to 0. In this way, the point spread function within each first numerical range can be approximately regarded as a linear monotonically decreasing function, thereby greatly reducing the hardware overhead when performing linear interpolation calculations, reducing the cost of hardware chips such as IP / IC / SOC, and also improving program operation efficiency and video frame rate.
[0113] In some exemplary embodiments, using the inverse first-order derivative value corresponding to a second-order derivative value within each first numerical range as the diffusion slope between two diffusion distance tie points includes using the inverse first-order derivative value corresponding to the maximum value of the second-order derivative within each first numerical range as the diffusion slope between the two diffusion distance tie points. However, embodiments of the present disclosure are not limited to this.
[0114] In some exemplary embodiments, in step 140, the interval between two adjacent diffusion distance binding points is 2 k diffusion distance, k is a natural number greater than 0.
[0115] For example, taking the Gaussian function model as an example, Figure 7 As shown, in the low brightness area, the brightness diffusion weight change δw changes very little, that is, the inverse first-order derivative value tends to zero, and the diffusion curve is close to linear, that is, a linear model can be used instead of a curve model. In order to ensure that the inverse first-order derivative value is sufficiently close to zero, the embodiment of the present disclosure determines the segmentation threshold point (i.e., the diffusion distance binding point) through the second-order derivative. Select n segmentation threshold points th1, th2, ..., thn on the second-order derivative corresponding to the Gaussian function model, and the interval between two adjacent segmentation threshold points is 2 k The diffusion distance between two segmentation threshold points is calculated by linear interpolation.
[0116] In the process of hardwareizing display panel algorithm, backlight diffusion calculation is the part that consumes the most hardware resources, accounting for about 70 to 80% of the whole chip. Therefore, the design of the backlight diffusion calculation module is crucial. The backlight diffusion parameter lookup table is made in the embodiments of the present disclosure. During program running, the diffusion brightness data corresponding to the diffusion distance binding points can be directly read by computer software or hardware circuit, and the diffusion brightness data corresponding to the diffusion distance between two diffusion distance binding points can be calculated by linear interpolation, without complex operation, thereby reducing the program calculation overhead, reducing the hardware storage demand, greatly reducing the consumption of storage medium, and improving the data reading, running and operation efficiency. The data storage medium includes various forms of computer readable storage, such as RAM, cache, ROM, etc. The backlight diffusion parameter lookup table can be made into one-dimensional single chain or two-dimensional matrix, and different forms correspond to different calculation methods and application scenarios.
[0117] The embodiments of the present disclosure also provide a display control method, Figure 8 is a flowchart of the display control method according to the embodiments of the present disclosure. The display control method includes:
[0118] Step 210, setting the set backlight brightness of each light-emitting area according to the gray scale of the image to be displayed;
[0119] Step 220, obtaining the backlight diffusion parameters of the backlight module of the display device, wherein the backlight diffusion parameters of the backlight module are obtained in advance according to the method described in any embodiment of the present disclosure and stored in the display device;
[0120] Step 230, calculating the equivalent backlight brightness of each pixel according to the set backlight brightness of each light-emitting area and the backlight diffusion parameters;
[0121] Step 240, calculating the corresponding compensation data according to the equivalent backlight brightness of each pixel;
[0122] Step 250, controlling the backlight module to set the backlight brightness to light up the light-emitting area, and controlling the display panel to display the image according to the compensation data.
[0123] In some example embodiments, in step 210, setting the set backlight brightness of each light-emitting area according to the gray scale of the image to be displayed can include: setting the set backlight brightness of each light-emitting area according to the pixel gray scale statistical value corresponding to each light-emitting area.
[0124] The number of gray scales that the display image can present is 2 N When N is 8, 2 8= 256 grayscale levels. Generally speaking, the backlight brightness cannot be adjusted to so many levels. In this case, you can select an approximate brightness level based on the grayscale range.
[0125] In some exemplary embodiments, before obtaining the backlight diffusion parameters of the backlight module of the display device in step 220 , the backlight diffusion parameters may be stored in a memory of the display device and called during display control to implement various display control methods.
[0126] In some exemplary embodiments, in step 230, calculating the equivalent backlight brightness of each pixel according to the set backlight brightness of each light-emitting area and the backlight diffusion parameter includes:
[0127] For each pixel, follow the steps below to obtain the equivalent backlight brightness calculation formula of the pixel:
[0128] Determine all A*B effective luminous areas that affect pixel brightness, where A and B are positive integers;
[0129] Determine the diffusion weight data corresponding to the A*B effective luminous areas according to the distance from the pixel to the A*B effective luminous areas;
[0130] Calculate the total diffuse brightness of the A*B effective light-emitting areas in the pixel according to the diffuse weight data corresponding to the A*B effective light-emitting areas and the set backlight brightness;
[0131] The total diffuse brightness of A*B effective light-emitting areas in the pixel is taken as the equivalent backlight brightness of the pixel.
[0132] In some exemplary embodiments, when determining all A*B effective luminous areas that affect the brightness of a pixel, all A*B effective luminous areas that affect the brightness of the pixel can be determined according to the point spread function y=f(x), where A and B are positive integers. According to the effective range of the point spread function, the effective luminous area of each pixel can be obtained by reverse deduction. For example, the center of the pixel can be determined according to the diffusion radius r, and all luminous areas within the radius r are taken as effective luminous areas. The point spread function of the backlight module can be obtained in advance according to the method of the above embodiment and stored in the display device. For example, the display device manufacturer can obtain it by testing each model of the display device before leaving the factory, and store it in the memory of the display device, and call it when needed.
[0133] In other exemplary embodiments, a backlight diffusion parameter lookup table includes A*B effective luminous areas and corresponding diffusion weight data for each pixel. The present disclosure stores the A*B effective luminous areas and corresponding diffusion weight data for each pixel in the backlight diffusion parameter lookup table, eliminating the need for recalculation each time. During display control, the equivalent backlight brightness of each pixel is calculated based on the effective luminous areas, corresponding diffusion weight data, and the set backlight brightness.
[0134] In some exemplary embodiments, for each pixel, the calculation formula for the equivalent backlight brightness may be weight normalized, wherein the weight normalization process includes:
[0135] Calculate the weighted sum of A*B effective luminous areas:
[0136] The normalized weight corresponding to each effective luminous area is calculated based on the calculated weights.
[0137] Afterwards, the normalized weights of all effective luminous areas of each pixel are stored as backlight diffusion parameters and directly used for the calculation of equivalent backlight brightness without the need to recalculate each time.
[0138] In step 240 , after the equivalent backlight brightness of the pixel is obtained, corresponding compensation calculations can be performed to obtain corresponding compensation data.
[0139] In step 250 , the backlight module is controlled to set the backlight brightness to illuminate the light-emitting area, and the display panel is controlled to display an image according to the compensation data.
[0140] For ease of understanding, the operations that can be performed before dynamic dimming display control are summarized. The overall process from measuring the point spread function of the luminous area to finally obtaining the diffusion weight parameter is as follows:
[0141] (1) Data acquisition: obtaining light diffusion data of multiple pixels.
[0142] (2) Data preprocessing to obtain the data of backlight diffusion range and effective pixels.
[0143] (3) Point spread function fitting: function fitting is performed based on the data of effective pixels to obtain the point spread function.
[0144] (4) Calculate the pixel backlight diffusion weight according to the fitted point spread function, that is, calculate the diffusion weight of all effective luminous areas of each pixel.
[0145] (5) Normalize the diffusion weights.
[0146] (6) Obtain the final backlight diffusion parameter lookup table and store it.
[0147] Thus, in step 220, when acquiring the backlight diffusion parameters of the backlight module, the effective luminous area and normalized weight data for each pixel can be obtained. In step 230, the equivalent backlight brightness of each pixel is calculated based on the set backlight brightness of each luminous area and the backlight diffusion parameters. The equivalent backlight brightness is calculated by directly calling the stored effective luminous area and normalized weight parameters. This allows the equivalent backlight brightness of each pixel to be quickly obtained through simple matrix operations, speeding up the calculation.
[0148] During local dynamic dimming, backlight adjustments must be performed for each frame (or every few frames, depending on the control algorithm). Each time the backlight is adjusted, the equivalent backlight brightness of each pixel must be recalculated. Therefore, computational speed is crucial. Storing the A*B effective luminous areas and their corresponding diffusion weights or normalized weights, and directly accessing them during display control, can significantly improve computational speed.
[0149] The display control method of the embodiment of the present disclosure, by accurately modeling the diffusion of the luminous area and storing the diffusion weight of the effective luminous area corresponding to each pixel, can conveniently obtain the brightness diffusion coefficient from the luminous area to the pixel at any distance, so as to facilitate accurate and rapid calculation of the equivalent backlight of each pixel during the display process, obtain a backlight distribution with a smooth transition close to the actual backlight diffusion brightness, and then obtain corresponding compensation data to achieve the same or even better display effect as full backlight display. The display control method of the embodiment of the present disclosure makes the image closer to the actual brightness of the original image in the non-low grayscale range, reduces the image distortion, and has good image quality, high contrast, low distortion rate, and no blockiness and dividing lines. In addition, due to the reduction of the backlight brightness in the relatively dark areas of the image, better contrast can also be obtained overall.
[0150] An embodiment of the present disclosure also provides a display control device, comprising a memory; and a processor connected to the memory, wherein the memory is used to store instructions, and the processor is configured to execute the steps of the display control method described in any embodiment of the present disclosure based on the instructions stored in the memory.
[0151] like Figure 9As shown, in one example, a driving module of a display device may include: a processor 910, a memory 920, a bus system 930, and a transceiver 940, wherein the processor 910, the memory 920, and the transceiver 940 are connected via the bus system 930, the memory 920 is used to store instructions, and the processor 910 is used to execute the instructions stored in the memory 920 to control the transceiver 940 to send and receive signals. Specifically, the transceiver 940 may receive an image to be displayed under the control of the processor 910, and the processor 910 sets the set backlight brightness of each light-emitting area according to the grayscale of the image to be displayed; obtains the backlight diffusion parameter of the backlight module, wherein the backlight diffusion parameter of the backlight module is pre-obtained according to the backlight diffusion parameter generation method as described in any embodiment of the present disclosure and stored in the display device; calculates the equivalent backlight brightness of each pixel according to the set backlight brightness of each light-emitting area and the backlight diffusion parameter; calculates corresponding compensation data according to the equivalent backlight brightness of each pixel; controls the backlight module to illuminate the light-emitting area with the set backlight brightness, and controls the display panel to display an image according to the compensation data.
[0152] It should be understood that the processor 910 may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc.
[0153] The memory 920 may include a read-only memory and a random access memory, and provides instructions and data to the processor 910. A portion of the memory 920 may also include a non-volatile random access memory. For example, the memory 920 may also store information about the device type.
[0154] In addition to the data bus, the bus system 930 may also include a power bus, a control bus, and a status signal bus. Figure 9 Various buses are labeled as bus system 930 .
[0155] In the implementation process, the processing performed by the processing device can be completed by the integrated logic circuit of the hardware in the processor 910 or the instructions in the form of software. That is, the method steps of the embodiments of the present disclosure can be embodied by the hardware processor to complete, or by the combination of hardware and software modules in the processor to complete. The software module can be located in a storage medium such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, register, or the like. The storage medium is located in the memory 920, and the processor 910 reads the information in the memory 920 and completes the steps of the above method in combination with the hardware. To avoid repetition, it will not be described in detail here.
[0156] The embodiments of the present disclosure also provide a display device, which comprises the display control device, the display panel and the backlight module according to any one of the embodiments of the present disclosure.
[0157] The embodiments of the present disclosure also provide a computer readable storage medium, which stores a computer program, and the program is executed by a processor to implement the display control method according to any one of the embodiments of the present disclosure. The method for controlling the display of the display device by executing executable instructions is basically the same as the display control method provided by the above-mentioned embodiments of the present disclosure, and will not be described here.
[0158] In some possible implementation manners, various aspects of the display control method provided by the present disclosure can also be implemented in the form of a program product, which includes program codes for causing a computer device to execute the steps in the display control method according to various exemplary embodiments of the present disclosure described above when the program product runs on the computer device. For example, the computer device can execute the display control method described in the embodiments of the present disclosure.
[0159] The program product can adopt any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium may, for example, but is not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or component, or any combination of the above. More specific examples (non-exhaustive list) of readable storage media include an electrical connection having one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.
[0160] It will be appreciated by those skilled in the art that all or some of the steps, systems, and functional modules / units in the methods disclosed above may be implemented as software, firmware, hardware, and appropriate combinations thereof. In hardware implementations, the division between the functional modules / units mentioned in the above description does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed by several physical components in cooperation. Some or all components may be implemented as software executed by a processor, such as a digital signal processor or a microprocessor, or implemented as hardware, or implemented as an integrated circuit, such as an application-specific integrated circuit. Such software may be distributed on a computer-readable medium, which may include a computer storage medium (or non-transitory medium) and a communication medium (or temporary medium). As is well known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable, and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and can be accessed by a computer. In addition, it is well known to those skilled in the art that communication media generally embodies computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.
[0161] Although the embodiments disclosed in this disclosure are as described above, the contents described are merely embodiments adopted to facilitate understanding of the disclosure and are not intended to limit the disclosure. Any person skilled in the art may make any modifications and changes in the form and details of the implementation without departing from the spirit and scope of the disclosure. However, the scope of patent protection of the disclosure shall still be based on the scope defined by the appended claims.
Claims
1. A method for generating backlight diffusion parameters, for use in a display device comprising a backlight module and a display panel, wherein the backlight module comprises a light-emitting panel and an optical film group located between the light-emitting panel and the display panel; The light-emitting plate includes a plurality of light-emitting areas, and the display panel includes a plurality of pixels; the method includes: selecting and measuring light spread data of at least one of the plurality of light-emitting areas, wherein the light spread data includes brightness data of a plurality of pixels on a display panel when only one of the light-emitting areas is illuminated, and distance data between positions corresponding to the plurality of pixels and a position of the illuminated light-emitting area; Preprocessing the light diffusion data to obtain effective pixels; Performing function fitting based on the data corresponding to the plurality of effective pixels to obtain a point spread function representing the relationship between diffusion brightness and diffusion distance; A backlight diffusion parameter lookup table is stored, the backlight diffusion parameter lookup table including a plurality of diffusion distance binding points and a diffusion brightness corresponding to each diffusion distance binding point, and a diffusion slope between two adjacent diffusion distance binding points, the diffusion slope being used to interpolate and calculate the diffusion brightness corresponding to the diffusion distance between the two diffusion distance binding points; wherein the point spread function is a function model of at least one of the following: Gaussian function model: ; Sine function model: ; Fourier function model: ; Where n is the order, 、 、 , w is the coefficient, x is the backlight diffusion distance, Diffuse brightness.
2. The method according to claim 1, wherein The preprocessing of the light diffusion data includes: The light diffusion data is truncated, and the truncated data is normalized.
3. The method according to claim 1, wherein The interval between two adjacent diffusion distance binding points is 2 k diffusion distance, k is a natural number greater than 0.
4. A method for generating backlight diffusion parameters, for use in a display device comprising a backlight module and a display panel, wherein the backlight module comprises a light-emitting panel and an optical film group located between the light-emitting panel and the display panel; The light-emitting plate includes a plurality of light-emitting areas, and the display panel includes a plurality of pixels; the method includes: selecting and measuring light spread data of at least one of the plurality of light-emitting areas, wherein the light spread data includes brightness data of a plurality of pixels on a display panel when only one of the light-emitting areas is illuminated, and distance data between positions corresponding to the plurality of pixels and a position of the illuminated light-emitting area; Preprocessing the light diffusion data to obtain effective pixels; Performing function fitting based on the data corresponding to the plurality of effective pixels to obtain a point spread function representing the relationship between diffusion brightness and diffusion distance; A backlight diffusion parameter lookup table is stored, wherein the backlight diffusion parameter lookup table includes multiple diffusion distance binding points and the diffusion brightness corresponding to each diffusion distance binding point, and also includes a diffusion slope between two adjacent diffusion distance binding points, wherein the diffusion slope is used to interpolate and calculate the diffusion brightness corresponding to the diffusion distance between the two diffusion distance binding points, wherein the backlight diffusion parameter lookup table is calculated as follows: performing an inverse first-order derivative and a second-order derivative on the point spread function; selecting one or more first numerical ranges, wherein the maximum value of the second-order derivative within each of the first numerical ranges is less than a preset second-order derivative threshold, and the difference between the maximum value and the minimum value of the second-order derivative within each of the first numerical ranges is less than a preset second-order derivative difference threshold; The diffusion distances corresponding to both ends of each first numerical range are used as two diffusion distance binding points, and the inverse first-order derivative value corresponding to a second-order derivative value within each first numerical range is used as the diffusion slope between the two diffusion distance binding points.
5. The method according to claim 4, wherein The method of using the inverse first-order derivative value corresponding to each second-order derivative value within the first numerical range as the diffusion slope between the two diffusion distance binding points includes: The inverse first-order derivative value corresponding to the maximum value of each second-order derivative within the first numerical range is used as the diffusion slope between the two diffusion distance binding points.
6. The method according to claim 4, wherein: The interval between two adjacent diffusion distance binding points is 2 k diffusion distance, k is a natural number greater than 0.
7. A display control method, comprising: Setting the backlight brightness of each light-emitting area according to the grayscale of the image to be displayed; Acquiring backlight diffusion parameters of a backlight module of a display device, wherein the backlight diffusion parameters of the backlight module are pre-acquired according to the method of any one of claims 1 to 6 and stored in the display device; Calculating the equivalent backlight brightness of each pixel based on the set backlight brightness and backlight diffusion parameters of each luminous area; Calculate corresponding compensation data according to the equivalent backlight brightness of each pixel; The backlight module is controlled to light up the light-emitting area to set the backlight brightness, and the display panel is controlled to display an image according to the compensation data.
8. A display control device comprising a memory; and a processor connected to the memory, the memory being configured to store instructions, the processor being configured to execute the steps of the display control method according to claim 7 based on the instructions stored in the memory.
9. A display device comprising the display control device according to claim 8, a display panel and a backlight module.
10. A computer-readable storage medium having a computer program stored thereon, wherein when the program is executed by a processor, the display control method according to claim 7 is implemented.
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