Gamma debugging method, computer readable storage medium and computer program product

Abstract

The invention provides a gamma debugging method, a computer readable storage medium and a computer program product, and the gamma debugging method comprises the steps: detecting whether the brightness and chrominance when a display module carries out the display through employing a first gamma register value meets a first brightness and chrominance index, and the first gamma register value is a current value of a gamma register of the display module; if the detection result is no, a first difference value between the first gamma register value and the reference gamma register value is calculated, an initial correction coefficient is obtained and used for correcting the first difference value to obtain a first adjustment amount, and the initial correction coefficient is used for representing the correlation between the actual adjustment amount and the theoretical adjustment amount; and adjusting the first gamma register value by using the first adjusting quantity, writing a second gamma register value obtained after adjustment into the gamma register, and repeatedly executing the step of detecting whether the brightness and chrominance when the display module displays by using the first gamma register value meet the first brightness and chrominance index or not until the detection result is yes.

Description

Technical Field

[0001] The present disclosure relates to the field of display technology, and more specifically, to a gamma debugging method, a computer-readable storage medium, and a computer program product. Background Art

[0002] Organic Light Emitting Diode (OLED) display screens have the characteristics of bright colors, high contrast, faster response and more energy saving, and are widely used in more and more electronic products.

[0003] In OLED display screens, brightness and chromaticity are important performance indicators. In related technologies, gamma tuning is used to ensure the brightness and chromaticity performance of the display screen. In the gamma tuning scheme, the display screen needs to be debugged to obtain the target gamma register value. However, the conventional gamma tuning scheme requires many debugging times and takes a long time. Summary of the invention

[0004] The purpose of the present disclosure is to provide a gamma debugging method, a computer-readable storage medium, and a computer program product to solve the technical problem of high number of gamma debugging times and long time consumption in the related art.

[0005] In order to achieve the above objectives, the present invention adopts the following technical solutions:

[0006] The present disclosure provides a gamma debugging method in a first aspect, comprising the following steps:

[0007] Detecting whether the brightness and chromaticity of the display module meets a first brightness and chromaticity index when the display module uses a first gamma register value for display, wherein the first gamma register value is a current value of a gamma register of the display module;

[0008] If the detection result is no, calculate the first difference between the first gamma register value and the reference gamma register value, obtain an initial correction coefficient and use the initial correction coefficient to correct the first difference to obtain a first adjustment amount, the reference gamma register value is a theoretical gamma register value calculated according to the reference brightness and chromaticity, the initial correction coefficient is used to represent the correlation between the actual adjustment amount and the theoretical adjustment amount, the actual adjustment amount is the change amount required for the first gamma register value to be adjusted to the target gamma register value, the theoretical adjustment amount is the change amount required for the first gamma register value to be adjusted to the reference gamma register value, the reference gamma register value is a theoretical gamma register value calculated according to the reference brightness and chromaticity, and the target gamma register value is the actual gamma register value when the brightness and chromaticity of the display module meet the first brightness and chromaticity index;

[0009] The first gamma register value is adjusted using the first adjustment amount, and the second gamma register value obtained after the adjustment is written into the gamma register, and the step of detecting whether the brightness and chromaticity of the display module meet the first brightness and chromaticity index when the display module uses the first gamma register value for display is repeatedly executed until the detection result is yes.

[0010] Optionally, before the step of obtaining the initial correction coefficient, the step further includes:

[0011] Determining whether the adjustment step size of the gamma register is too small or too large;

[0012] If the adjustment step is too small, the initial correction coefficient is adjusted using the first weight coefficient, and the first adjustment amount increases when the adjusted initial correction coefficient corrects the first difference;

[0013] If the adjustment step is too large, the initial correction coefficient is adjusted using the second weight coefficient, and the first adjustment amount is reduced when the adjusted initial correction coefficient is used to correct the first difference.

[0014] Optionally, the step of determining whether the adjustment step size of the gamma register is too small or too large includes:

[0015] Acquire brightness and chromaticity measured multiple times continuously, each brightness and chromaticity is the brightness and chromaticity of the display module after adjusting the first gamma register value once;

[0016] Determine whether the brightness and chromaticity measured for the plurality of consecutive times continuously increase or decrease, and if so, determine that the adjustment step length is too small;

[0017] It is determined whether the brightness and chromaticity measured continuously for multiple times fluctuate around the reference brightness and chromaticity. If the determination result is yes, it is determined that the adjustment step is too large.

[0018] Optionally, the display module includes a plurality of display brightness intervals, each display brightness interval includes a plurality of binding point grayscales, each binding point grayscale corresponds to an initial correction coefficient, and before the step of detecting whether the brightness and chromaticity of the display module meets the first brightness and chromaticity index when the display module uses the first gamma register value for display, the step also includes:

[0019] For any display brightness interval, pre-debugging is performed on each binding point grayscale within the display brightness interval in turn to determine an initial correction coefficient corresponding to the binding point grayscale.

[0020] Optionally, for any binding point grayscale within any display brightness range, the step of pre-debugging the binding point grayscale to determine an initial correction coefficient corresponding to the binding point grayscale includes:

[0021] Detecting whether the brightness and chromaticity of the display module meets the second brightness and chromaticity index when the display module uses the third gamma register value for display, wherein the third gamma register value is the current value of the gamma register;

[0022] If the detection result is yes, output the third gamma register value, and calculate the initial correction coefficient using the third gamma register value, the previous register value of the gamma register, and the reference gamma register value;

[0023] If the detection result is no, calculating a second difference between the third gamma register value and the reference gamma register value, obtaining a preset correction coefficient, and using the preset correction coefficient to correct the second difference to obtain a second adjustment amount;

[0024] The third gamma register value is adjusted using the second adjustment amount, and the fourth gamma register value obtained after adjustment is written into the gamma register, and the step of detecting whether the brightness and chromaticity of the display module meets the second brightness and chromaticity index when the display module uses the third gamma register value for display is repeatedly executed until the detection result is yes.

[0025] Optionally, after the step of outputting the third gamma register value, the step further includes:

[0026] Determine whether the current debugging number is equal to the first value;

[0027] If the current debugging number is greater than the first value, executing the step of calculating the initial correction coefficient using the third gamma register value, the previous register value of the gamma register, and the reference gamma register value;

[0028] If the current debugging times is equal to the first value, the initial correction coefficient is calculated using the third gamma register value and the reference gamma register value, or the initial correction coefficient of the current binding point grayscale is interpolated using the initial correction coefficients of the binding point grayscales adjacent to the current binding point grayscale.

[0029] Optionally, for any display brightness interval, after the step of sequentially pre-debugging each binding point grayscale within the display brightness interval to determine the initial correction coefficient corresponding to the binding point grayscale, the step further includes:

[0030] Detect whether the initial correction coefficient corresponding to the grayscale of each binding point is an abnormal value;

[0031] When the initial correction coefficient corresponding to the grayscale of any binding point is an abnormal value, the initial correction coefficient corresponding to the grayscale of the binding point is calculated using a linear interpolation method and the initial correction coefficient of the grayscale of the binding point is updated to a linear interpolation calculation result.

[0032] Optionally, the step of calculating a first difference between the first gamma register value and the reference gamma register value includes:

[0033] Obtaining the current brightness and color of the display module when the display module uses the first gamma register value for display;

[0034] converting the current brightness and chromaticity into current spectral tristimulus values ​​and converting the reference brightness and chromaticity into reference spectral tristimulus values ​​according to a first conversion relationship, wherein the first conversion relationship represents a conversion relationship between brightness and chromaticity and spectral tristimulus values;

[0035] The difference between the current spectral tristimulus value and the reference spectral tristimulus value is calculated and the difference is converted into the first difference using a second conversion relationship, wherein the second conversion relationship represents a conversion relationship between a gamma register value and a spectral tristimulus value.

[0036] Optionally, the step of detecting whether the brightness and chromaticity of the display module meets the first brightness and chromaticity index when the display module uses the first gamma register value for display includes:

[0037] Measuring the current brightness and chromaticity when the display module uses the first gamma register value for display, and converting the current brightness and chromaticity into current spectral tristimulus values ​​according to the first conversion relationship;

[0038] It is determined whether the error between the current spectral tristimulus value and the reference spectral tristimulus value is less than a first error threshold, and when the determination result is yes, it is determined that the brightness and chromaticity of the display module meets the first brightness and chromaticity index.

[0039] Optionally, the display module includes a plurality of display brightness intervals, each display brightness interval corresponds to a second conversion relationship, each display brightness interval includes a plurality of binding point grayscales, and the gamma debugging method includes:

[0040] For any display brightness range, the second conversion relationship corresponding to the display brightness range is used to adjust the first gamma register values ​​of each binding point grayscale in the display brightness range in turn to obtain the first gamma register values ​​of each binding point grayscale that make the brightness and chromaticity of the display module meet the first brightness and chromaticity index.

[0041] Optionally, before the step of calculating the first difference between the first gamma register value and the reference gamma register value, the step further includes:

[0042] Writing the fifth gamma register value into the gamma register, obtaining the spectral tristimulus value of the display module when the display module uses the fifth gamma register value for display, the brightness of the display module when using the fifth gamma register value for display is greater than the brightness of the display module when using the maximum grayscale for display;

[0043] The second conversion relationship is determined according to the fifth gamma register value and the spectral tristimulus values.

[0044] A second aspect of the present disclosure provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the gamma debugging method described above when the program is executed by a processor.

[0045] A third aspect of the present disclosure provides a computer program product, including a computer program, which implements the steps of the gamma debugging method described above when executed by a processor.

[0046] The beneficial effects of the present disclosure are as follows:

[0047] The gamma debugging method of the embodiment of the present disclosure adds a correction coefficient during the gamma debugging process. The correction coefficient can represent the correlation between the actual adjustment amount and the theoretical adjustment amount. During the gamma debugging process, the correction coefficient is used to correct the theoretical adjustment amount in real time, so that the theoretical adjustment amount changes in the direction of the actual adjustment amount. In this way, the problem of large deviations in the gamma register value due to uncertain factors such as optical device errors and ambient light can be prevented, and the gamma register value can be moved closer to the target gamma register value more quickly and accurately, thereby reducing the number of gamma debugging times, shortening the debugging cycle, and improving the production line capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The specific implementation methods of the present disclosure are further described in detail below with reference to the accompanying drawings.

[0049] Figure 1 A flow chart of the gamma debugging method provided in the embodiment of the present disclosure performing pre-debugging on any binding point grayscale within any display brightness interval to determine the initial correction coefficient corresponding to the binding point grayscale;

[0050] Figure 2 A flowchart of another embodiment for determining the initial correction coefficient corresponding to the grayscale of any binding point;

[0051] Figure 3 A relationship curve between the grayscale of the binding point and the initial correction coefficient m0 ​​provided in the embodiment of the present disclosure;

[0052] Figure 4 A flowchart for judging the abnormal value of the initial correction coefficient m0 ​​of the gray scale of each binding point;

[0053] Figure 5 This is a flow chart for performing gamma debugging on any display brightness interval in the second debugging stage. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0055] Unless otherwise defined, the technical terms or scientific terms used in the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, similar words such as "one", "one" or "the" do not indicate quantity restrictions, but indicate that there is at least one. Similar words such as "include" or "comprise" mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Similar words such as "connect" or "connected" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0056] In the related art, during the gamma debugging of the display module, due to the influence of uncertain factors such as optical device errors and ambient light, the gamma register value calculated according to the theoretical formula may have a large deviation from the target gamma register value of the display module, resulting in a large number of debugging times and a long time consumption during the gamma debugging process. The target gamma register value here represents the actual gamma register value required to meet the customer's brightness and chromaticity requirements when the display module is displayed.

[0057] In order to solve the above technical problems, the embodiments of the present disclosure provide a gamma debugging method, a computer-readable storage medium, and a computer program product, which are described below in conjunction with various specific embodiments.

[0058] In the disclosed embodiment, the display module includes multiple display brightness bands, each display brightness band includes multiple binding point grayscales, and the display brightness of the display module is different when displaying different grayscale images in the same display brightness band, and the display brightness is also different when displaying the same grayscale image in different display brightness bands. Therefore, when gamma debugging is performed on a certain display module, it is necessary to debug each binding point grayscale in each display brightness band of the display module in turn to obtain the gamma register value corresponding to each binding point grayscale in each display brightness band.

[0059] Correspondingly, the customer standard (Specification, referred to as SPEC) has different brightness and chromaticity requirements for different display brightness ranges and different binding point grayscales, that is, the reference brightness and chromaticity to be achieved for different display brightness ranges and different binding point grayscales are different. Among them, brightness and chromaticity are usually represented by brightness and chromaticity coordinates (L, x, y), where L represents brightness, and the unit is usually nits, and x and y are used to describe the hue and saturation of the display.

[0060] Among them, the binding point grayscale is a number of representative grayscales (generally 15-35) selected from all grayscales, and the binding point grayscale is used as the main object of gamma debugging when debugging the display module. Exemplarily, for a display module with an 8-bit bit depth, the binding point grayscale includes 19, namely: 3, 7, 11, 19, 23, 31, 39, 47, 55, 63, 79, 95, 111, 144, 173, 205, 226, 247, 255. When gamma debugging the display module, it is necessary to debug the gamma register values ​​corresponding to these 19 binding point grayscales for each display brightness interval. It can be understood that the binding point grayscale can also be other numbers and other grayscale values, which are not limited in the embodiments of the present disclosure.

[0061] For a display module, if a certain pixel includes a red sub-pixel, a green sub-pixel and a blue sub-pixel, the display module includes four groups of gamma registers, which are respectively represented as gamma registers W reg , R reg , G reg , B reg Among them, the gamma register R reg Register value for storing red sub-pixel (R, 0, 0), gamma register G reg Register value for storing green sub-pixel (0, G, 0), gamma register B reg Register value for storing blue sub-pixel (0,0,B), gamma register W reg Register values ​​(R, G, B) used to store the red, green, and blue sub-pixels.

[0062] The gamma debugging method provided in the embodiment of the present disclosure is mainly divided into two stages: a first debugging stage and a second debugging stage.

[0063] The first debugging stage is the pre-debugging stage, which can also be understood as the training stage of the initial correction coefficient. In the pre-debugging stage, the display module needs to be initially debugged so that the brightness and chromaticity of the display module meet the customer standards. After the first debugging stage, the initial gamma register value and the initial correction coefficient m0 ​​can be obtained, wherein the initial correction coefficient m0 ​​is related to the screen characteristics of the display module, and the initial gamma register value and the initial correction coefficient m0 ​​are used as the basis for the second debugging stage. Specifically, the initial correction coefficient m0 ​​is used to represent the correlation between the actual adjustment amount and the theoretical adjustment amount, the actual adjustment amount is the change required for the first gamma register value to be adjusted to the target gamma register value, the theoretical adjustment amount is the change required for the first gamma register value to be adjusted to the reference gamma register value, the reference gamma register value is the theoretical gamma register value calculated according to the reference brightness and chromaticity, and the target gamma register value is the actual gamma register value when the brightness and chromaticity of the display module meets the first brightness and chromaticity index.

[0064] In specific implementation, the first debugging stage can debug the sample display modules in a batch of display modules, and write the initial gamma register value and initial correction coefficient m0 ​​obtained by debugging into each display module of this batch, and then each display module enters the second debugging stage. Since the initial correction coefficient m0 ​​is obtained by actual debugging of the sample display module, it can characterize the correlation between the actual adjustment amount and the theoretical adjustment amount of the display module of this batch. Therefore, when the initial correction coefficient m0 ​​is used for debugging, it can be closer to the target gamma register value more quickly and accurately, and for different display brightness intervals, the correction coefficient suitable for this display brightness interval is trained respectively, which is more in line with the characteristics of this display brightness interval, so the gamma debugging speed of each display brightness interval can be accelerated.

[0065] It is understandable that there are many uncertain factors in the debugging process, such as errors in the optical equipment for measuring the brightness and chromaticity of the display module, differences in the degree of influence of ambient light, and differences between each display module. Therefore, although the first debugging stage can make the display module meet customer standards, after the initial gamma register value is written to each display module, the brightness and chromaticity of each display module during display may still not meet customer standards. Therefore, it is necessary to enter the second debugging stage. In the second debugging stage, the gamma register value of the display module is mainly debugged again to obtain the gamma register value that makes the brightness and chromaticity of the display module meet customer standards.

[0066] The gamma debugging method of the embodiment of the present disclosure needs to predetermine two conversion relationships before debugging, namely a first conversion relationship and a second conversion relationship. The first conversion relationship represents the conversion relationship between brightness and chromaticity and spectral tristimulus values, and the second conversion relationship represents the conversion relationship between gamma register values ​​and spectral tristimulus values.

[0067] For the display module, the first conversion relationship between brightness chromaticity and spectral tristimulus values ​​can be expressed as: Y=L, X=(x / y)*Y, Z=((1-xy) / y)*Y, where L, x, y represent brightness chromaticity coordinates, and X, Y, Z represent spectral tristimulus values.

[0068] For the display module, the maximum brightness that can be achieved in different display brightness ranges is different. In different display brightness ranges, even if the gamma register value is the same, the optical data of the display module (such as brightness chromaticity or spectral tristimulus values) may also be different. Please refer to Table 1, which shows the brightness chromaticity data measured in different display brightness ranges when the gamma register value is the same.

[0069] Table 1 Brightness and chromaticity data of different bands with the same gamma register value

[0070]

[0071] In Table 1, band1, band2, and band3 represent three different display brightness ranges. The gamma register W reg The corresponding brightness and chromaticity data are represented by gamma register W reg The brightness and chromaticity of the display module measured when the display module is lit by the register value (R, G, B) of reg The corresponding brightness and chromaticity data are represented by gamma register R reg The brightness and color of the display module measured when the display module is lit by the register value (R, 0, 0); the gamma register G reg The corresponding brightness and chromaticity data are represented by the gamma register G reg The brightness and chromaticity of the display module measured when the display module is lit by the register value (0, G, 0); Gamma register B reg The corresponding brightness and chromaticity data are represented by gamma register B reg The brightness and chromaticity of the display module measured when the display module is lit with the register value (0,0,B).

[0072] It can be seen from Table 1 that even if the gamma register value is the same, the brightness and chromaticity measured in different display brightness ranges are different. Therefore, it is necessary to determine the second conversion relationship between the gamma register value and the spectral tristimulus value for each display brightness range.

[0073] Optionally, the process of determining the second conversion relationship includes the following steps (11) and (12).

[0074] (11) Writing the fifth gamma register value into the gamma register, obtaining the spectral three-stimulus values ​​of the display module when the display module uses the fifth gamma register value to perform gamma adjustment, and the brightness of the display module when using the fifth gamma register value for display is greater than the brightness of the display module when using the maximum grayscale for display.

[0075] (12) Determining the second conversion relationship according to the fifth gamma register value and the spectral tristimulus value.

[0076] The selection of the fifth gamma register value needs to meet certain conditions. Specifically, when the display module is lit using the fifth gamma register value, the brightness of the display module is greater than the brightness of the highest grayscale. Exemplarily, the fifth gamma register value is expressed as reg=((2 depth -1) / 5)*4, take the integer when reg is a decimal, where depth represents the number of bits of the gamma register value, for example, depth = 8, 10, 12, 14, etc. At this time, the four groups of gamma registers W reg , R reg , G reg , B reg The gamma register values ​​are represented as Reg- W =(reg,reg,reg),Reg- R =(reg,0,0),Reg- G =(0,reg,0),Reg- B =(0,0,reg), respectively print the picture (that is, light up the display module) to measure four groups of brightness and chromaticity, and the four groups of brightness and chromaticity are converted according to the first conversion relationship to obtain the corresponding spectral tristimulus values, which are respectively expressed as XYZ W =(X w ,Y w ,Z w ), XYZ R =(X R ,Y R ,Z R ), XYZ G =(X G ,Y G ,Z G ), XYZ B =(X B ,Y B ,Z B ), where XYZ W Indicates the use of gamma register value Reg- W = (reg, reg, reg) The spectral tristimulus values ​​of the module are displayed when printing. Similarly, XYZ R Indicates the use of gamma register value Reg- R= (reg, 0, 0) The spectral tristimulus value of the display module when printing, and XYZ can be obtained by analogy. G and XYZ B .

[0077] The second conversion relationship can be expressed in matrix form. For example, the second conversion relationship is expressed by the intermediate conversion matrix T1, the four groups of gamma register values ​​are expressed by the matrix A, and the four groups of spectral tristimulus values ​​are expressed by the matrix B:

[0078]

[0079] Then the intermediate conversion matrix T1 = (A T *A) -1 *A T *B(Formula 1)

[0080] Among them A T represents the transposed matrix of matrix A, (A T *A) -1 Indicates (A T *A), (A T *A) -1 *A T represents the pseudo-inverse matrix of matrix A, T1 represents the transformation of matrix B using the pseudo-inverse matrix to obtain the projection or least squares solution of matrix B on the column space of matrix A.

[0081] Multiply both sides of the above formula 1 by A*T1 -1 , Formula 1 can be transformed into Formula 2:

[0082] A=B*T1 -1 (Formula 2)

[0083] From formula 2, we can see that using the inverse matrix T1 of the intermediate conversion matrix T1 -1 , the spectral tristimulus values ​​XYZ can be converted into gamma register values ​​Reg.

[0084] The fifth gamma register value and the calculated spectral tristimulus value XYZ W 、XYZ R 、XYZ G 、XYZ B It is saved in a CSV file, and when the initial correction coefficient m0 ​​is trained in the first debugging phase, the data can be used to obtain the intermediate conversion matrix T1 representing the second conversion relationship.

[0085] During the gamma debugging process, assume that the gamma register value written to the gamma register for the i-th time is represented by Reg i At this time, the brightness and chromaticity of the display module measured by optical equipment during display is expressed as Lxy i=(L i ,x i ,y i ), according to the first conversion relationship, the luminance and chromaticity Lxy i The corresponding spectral tristimulus is represented by XYZ i =(X i ,Y i ,Z i ). Similarly, assuming that the gamma register value written to the gamma register for the (i+1)th time is expressed as Reg i+1 At this time, the brightness and chromaticity of the display module measured by optical equipment during display is expressed as Lxy i+1 =(L i+1 ,x i+1 ,y i+1 ), according to the first conversion relationship, the luminance and chromaticity Lxy i+1 The corresponding spectral tristimulus is represented by XYZ i+1 =(X i+1 ,Y i+1 ,Z i+1 ). According to the first conversion relationship and the reference brightness and chromaticity, the reference spectral tristimulus value can be obtained. The reference spectral tristimulus value is expressed as XYZ t =(X t ,Y t ,Z t ,).

[0086] During the debugging process, assuming that the current debugging is the i-th debugging, the measured spectral tristimulus values ​​XYZ i With the reference spectrum tristimulus value XYZ t The difference XYZ D It is expressed as:

[0087]

[0088] According to formula 3, the current gamma register value Reg i and the reference gamma register value Reg t The difference of RGB D It can be expressed as:

[0089] RGB D =XYZ D *T1 -1 (Formula 4)

[0090] The (i+1)th debug gamma register value Reg i+1 The value of the gamma register Reg i The difference Reg error It is expressed as:

[0091] Reg error=Reg i+1 -Reg i ;

[0092] In theory, setting Reg i+1 =Reg i +RGB D When the gamma register value Reg i Adjust to the reference gamma register value Reg t At this time, the brightness and color of the display module can be adjusted directly to meet the customer's standards. The reference gamma register value Reg t It is based on the reference spectral tristimulus values ​​XYZ t The theoretical value calculated by the second conversion relationship. However, in the actual debugging process, due to the influence of uncertain factors such as optical device error and ambient light, the reference gamma register value Reg t There will be a certain deviation from the target gamma register value. Directly set Reg i+1 =Reg i +RGB D It will not be debugged successfully at one time, and may cause the adjusted gamma register value Reg i+1 There is a large deviation from the target gamma register value, which leads to more debugging times and longer debugging cycles. The target gamma register value here refers to the gamma register value actually required by the display module, that is, the gamma register value that makes the brightness of the display module meet the customer's standards. The gamma debugging process is the process of continuously debugging the gamma register value to gradually approach the target gamma register value.

[0093] In order to solve the problem of directly using Reg i+1 =Reg i +RGB D When the formula is debugged, there is a large deviation between the adjusted gamma register value and the target gamma register value, a large number of debugging times, and a long debugging cycle. In the embodiment of the present disclosure, a correction coefficient m is set, and the gamma adjustment process is corrected by using the correction coefficient m. Specifically, the change amount of the gamma register value during the gamma debugging process is corrected by using the correction coefficient. At this time, the approximation algorithm model (that is, the debugging model of the gamma register value) is expressed as the following formula 5:

[0094] Reg i+1 =Reg i +RGB D / m (Formula 5)

[0095] Further deformation of formula 5 can obtain the following formula 6:

[0096] Reg i+1 -Reg i=RGB D / m(Formula 6)

[0097] Multiply both sides of Formula 6 by (RGB D ) T The following formula 7 can be obtained:

[0098] (Reg i+1 -Reg i )*(RGB D ) T =RGB D *(RGB D ) T / m (Formula 7)

[0099] Multiply both sides of Formula 7 by (RGB D *(RGB D ) T ) -1 , we can get the following formula 8:

[0100] (Reg i+1 -Reg i )*(RGB D ) T *(RGB D *(RGB d ) T ) -1 =1 / m (Formula 8)

[0101] According to formula 8, the correction coefficient m can be expressed as:

[0102]

[0103] According to formula 9, the correction coefficient m is calculated based on the gamma register values ​​Reg i+1 , Reg i , the previous gamma register value Reg i and the reference gamma register value Reg t The difference of RGB D Determined together, the previous gamma register value Reg i and the reference gamma register value Reg t The difference of RGB D The intermediate conversion matrix T1 and the previous spectral tristimulus value XYZ can be used. i With the reference spectrum tristimulus value XYZ t Calculated.

[0104] At the end of the first debugging phase, based on the last gamma register value Reg i+1 , the previous gamma register value Regi , Difference RGB D The calculated correction coefficient m is the initial correction coefficient m0, which is used to represent the correlation between the actual adjustment amount and the theoretical adjustment amount. Specifically, at the end of the first adjustment stage, the last gamma register value Reg i+1 It can be understood as the target gamma register value of the first debugging stage, Reg i Indicates the gamma register value before adjustment, so Reg i+1 -Reg i It can represent the difference between the target gamma register value and the gamma register value before adjustment, that is, the actual adjustment amount. D It can represent the difference between the reference gamma register value and the gamma register value before adjustment, that is, the theoretical adjustment amount. Therefore, the initial correction coefficient m0 ​​can represent the difference between the actual adjustment amount and the theoretical adjustment amount (that is, RGB D ) between them.

[0105] The first adjustment stage of the gamma adjustment method is first introduced in detail below.

[0106] In the disclosed embodiment, the display module includes multiple display brightness intervals, each display brightness interval includes multiple binding point grayscales, and each binding point grayscale corresponds to an initial correction coefficient m0. Therefore, before entering the second debugging stage, the gamma debugging method includes: for any display brightness interval, pre-debugging each binding point grayscale within the display brightness interval in turn to determine the initial correction coefficient m0 ​​corresponding to the binding point grayscale, that is, before entering the second stage of debugging, pre-debugging is required to determine the initial correction coefficient m0.

[0107] Optional, such as Figure 1 As shown, for any binding point grayscale in any display brightness range, the step of pre-debugging the binding point grayscale to determine the initial correction coefficient corresponding to the binding point grayscale includes:

[0108] Step S101, detecting whether the brightness and chromaticity of the display module meets the second brightness and chromaticity index when the display module uses the third gamma register value for display, wherein the third gamma register value is the current value of the gamma register. When the detection result is yes, execute step S102, and when the detection result is no, execute step S104.

[0109] In the disclosed embodiment, when the debugger performs pre-debugging on the display module, he does not know any data in advance, that is, he does not know the initial gamma register value and the initial correction coefficient m0. At this time, the debugger can randomly write a value into the gamma register, which value can be, for example, (0,0,0) or an arbitrary value set by the debugger based on experience, and then perform pre-debugging based on this value. In order to distinguish it from the second debugging stage, the disclosed embodiment records the current value in the gamma register in the pre-debugging stage (that is, the first debugging stage) as the third gamma register value.

[0110] Among them, the second brightness and chromaticity index is determined according to the customer standard. Specifically, the customer standard stipulates the reference brightness and chromaticity of the display module at different binding point grayscales in different display brightness ranges. In specific implementation, when the error between the brightness and chromaticity of the display module and the reference brightness and chromaticity is within a certain range, it can be determined that the display module meets the customer standard. Exemplarily, the second brightness and chromaticity index indicates that the error between the brightness and chromaticity of the display module and the reference brightness and chromaticity is within 1%, that is, when the error between the brightness and chromaticity of the display module and the reference brightness and chromaticity is within 1%, the display module is considered to meet the customer standard, and if the error exceeds 1%, it does not meet the customer standard.

[0111] Since step S101 needs to use the second brightness and chromaticity index for judgment, before executing step S101, it is necessary to pre-process the customer standard to determine the reference brightness and chromaticity and the second brightness and chromaticity index.

[0112] Step S102, outputting the third gamma register value.

[0113] Step S103, calculating the initial correction coefficient by using the third gamma register value, the previous register value of the gamma register, and the difference between the previous gamma register value and the reference gamma register value.

[0114] Specifically, the calculation formula of the correction coefficient m can refer to Formula 9.

[0115] For example, assuming that the brightness and chromaticity of the display module meet the second brightness and chromaticity index, the current value of the gamma register is Reg9, that is, the third gamma register value is Reg9, then the gamma debugging method outputs the gamma register value Reg9, and obtains the previous gamma register value Reg8 of Reg9, the difference RGB between the previous gamma register value Reg8 and the reference gamma register value D , and then the initial correction coefficient m0 ​​can be calculated according to formula 9, for example:

[0116]

[0117] Among them, RGB D＝ XYZ D *T1 -1, XYZ D =XYZ t -XYZ8.

[0118] Step S104, calculate the second difference between the third gamma register value and the reference gamma register value, obtain a preset correction coefficient and use the preset correction coefficient to correct the second difference to obtain a second adjustment amount, use the second adjustment amount to adjust the third gamma register value, and write the fourth gamma register value obtained after adjustment into the gamma register, and repeat the step of detecting whether the brightness and chromaticity of the display module meets the second brightness and chromaticity index when the display module uses the third gamma register value for display until the detection result is yes.

[0119] The preset correction coefficient in step S104 is a value randomly set by the debugger for the correction coefficient m. For example, the debugger sets the preset correction coefficient to 10. Then the algorithm for adjusting the third gamma register value can be expressed as: Reg i+1 =Reg i +RGB D / m (m = 10), where RGB D That is, the second difference between the third gamma register value and the reference gamma register value, Reg i+1 That is, the adjusted gamma register value, Reg i Indicates the gamma register value before adjustment.

[0120] After the first debugging stage, the input data for calculating the initial correction coefficient m0 ​​of each binding point grayscale in each display brightness range can be obtained. For details, please refer to Table 2, which shows the data of each binding point grayscale obtained by debugging one of the display brightness ranges.

[0121] Table 2 Input data for training the initial correction coefficient m0

[0122]

[0123] Among them, in the first debugging stage, that is, the training stage of the initial correction coefficient m0, if the brightness and chromaticity of the display module meet the second brightness and chromaticity index in the first debugging, then there is only one gamma register value at this time. At this time, the gamma register values ​​R, G, and B before and after adjustment in Table 2 are the same, and the brightness and chromaticity L, x, and y before and after adjustment are also the same, which will cause the denominator in Formula 9 to be 0. At this time, the calculated initial correction coefficient m0 ​​is infinite, which is a singular point, and this case will cause the debugging program to be interrupted.

[0124] In order to solve this problem, after the step of outputting the third gamma register value in step S102, the following can be done: Figure 2As shown, it includes step S105 and step S106.

[0125] Step S105, determine whether the current number of debugging times is equal to the first value. If the judgment result is that the current number of debugging times is equal to the first value, execute step S106. If the judgment result is that the current number of debugging times is greater than the first value, execute the step of calculating the initial correction coefficient using the third gamma register value, the previous register value of the gamma register, and the reference gamma register value, that is, execute step S103, wherein the first value is 1.

[0126] Step S106, calculating the initial correction coefficient using the third gamma register value and the reference gamma register value, or interpolating the initial correction coefficient of the grayscale of the binding point adjacent to the grayscale of the binding point to obtain the initial correction coefficient of the grayscale of the binding point.

[0127] Among them, step S106 includes two solutions a and b:

[0128] a. Calculate the initial correction coefficient using the third gamma register value and the reference gamma register value.

[0129] At this time, the gamma register value Reg in formula 9 i is the current value of the gamma register, that is, the output third gamma register value, and the gamma register value Reg i+1 Replaced with the reference gamma register value Reg t , reference gamma register value Reg t According to formula 2, using the intermediate conversion matrix T1 and the reference spectral tristimulus value XYZ t Since optical devices usually have measurement errors, the gamma register value Reg i and the reference gamma register value Reg t They are usually not exactly the same, so the denominator is avoided.

[0130] b. The initial correction coefficient of the grayscale of the binding point adjacent to the grayscale of the binding point is interpolated to obtain the initial correction coefficient of the grayscale of the binding point.

[0131] In specific implementation, when the number of debugging times is 1, the initial correction coefficient m0 ​​of the grayscale of the binding point can be set to a temporary value, for example, the temporary value is 0. After that, after all the binding point grayscales in the current display brightness range are debugged, the initial correction coefficient m0 ​​of the binding point grayscale adjacent to the binding point grayscale can be interpolated and calculated by linear interpolation method.

[0132] In the embodiment of the present disclosure, when calculating the initial correction coefficient m0, a judgment step of the number of debugging times is added to judge whether the number of debugging times is 1. When the number of debugging times is greater than 1, the initial correction coefficient m0 ​​can be directly calculated according to Formula 9. When the number of debugging times is equal to 1, the initial correction coefficient m0 ​​needs to be calculated through step S106, that is, calculated by interpolation or using the reference gamma register value, so that the problem that the initial correction coefficient m0 ​​is infinite and is a singular point can be solved.

[0133] In a possible implementation, for any display brightness range, the step of pre-debugging each binding point grayscale within the display brightness range in turn to determine the initial correction coefficient corresponding to the binding point grayscale also includes the following steps: detecting whether the initial correction coefficient corresponding to each binding point grayscale is an abnormal value, and when the initial correction coefficient corresponding to any binding point grayscale is an abnormal value, using linear interpolation to calculate the initial correction coefficient corresponding to the binding point grayscale and updating the initial correction coefficient of the binding point grayscale to the linear interpolation calculation result.

[0134] In the disclosed embodiment, the debugging personnel analyzed the initial correction coefficient m0 ​​corresponding to each grayscale of the binding point under the same display brightness range of the display module and found that the value of the initial correction coefficient m0 ​​is positively correlated with the grayscale value of the binding point grayscale. The larger the grayscale value of the binding point grayscale, the larger the corresponding initial correction coefficient m0 ​​is usually. Please refer to Figure 3 , Figure 3 is the relationship curve between the grayscale of the binding point and the initial correction coefficient m0, Figure 3 The horizontal axis represents the grayscale value of the binding point grayscale, and the vertical axis represents the initial correction coefficient m0. In order to improve the accuracy of the initial correction coefficient m0 ​​obtained in the first debugging stage, the embodiment of the present disclosure adds an abnormal value judgment step after obtaining the initial correction coefficient m0 ​​of each binding point grayscale in a certain displayed brightness range. The abnormal value judgment step judges whether each initial correction coefficient m0 ​​is an abnormal value through the positive correlation between the initial correction coefficient m0 ​​and the binding point grayscale.

[0135] Optionally, assuming that the total number of grayscales of the binding points is N, the grayscales of the binding points are sorted from small to large according to the grayscale value, and the serial numbers of the grayscales of the binding points are represented by 1, 2, 3, ..., N, respectively. Then, the process of judging the abnormal value of the grayscales of the binding points is as follows: Figure 4 As shown, the following steps are included:

[0136] Step S201, obtaining the grayscale of the i-th binding point.

[0137] Step S202, determine whether i is less than or equal to N-2, if the determination result is yes, execute step S203, if the determination result is no, execute step S210.

[0138] Step S203, taking the grayscale values ​​of the i-th, (i+1)-th, and (i+2)-th binding point grayscales and the initial correction coefficient m0 ​​corresponding to the binding point grayscales, wherein the initial correction coefficient m0 ​​corresponding to the i-th binding point grayscale is expressed as m i .

[0139] Step S204, calculate the derivatives at the grayscale of the i-th binding point and the grayscale of the (i+1)-th binding point, respectively denoted as Δ i , Δ i+1 , respectively expressed as:

[0140] Step S205, determine Δ i and Δ i+1 Are they all greater than 0? If the judgment result is Δ i and Δ i+1 are all greater than 0, indicating that the initial correction coefficients of the grayscale of the i-th, (i+1)-th, and (i+2)-th binding points meet the requirements, and step S206 is executed; otherwise, an abnormal value has occurred. Specifically, if Δ i >0 and Δ i+1 <0, indicating that the initial correction coefficient m0 ​​of the grayscale of the (i+2)th binding point is an abnormal value, and step S207 is executed. i <0 and Δ i+1 <0, indicating that the initial correction coefficient m0 ​​of the grayscale of the (i+1)th binding point is an abnormal value, and step S208 is executed. i <0 and Δ i+1 >0, it indicates that the initial correction coefficient m0 ​​of the grayscale of the i-th binding point is an abnormal value, and step S209 is executed. After step S207 to step S209, the process jumps to step S206.

[0141] Step S206, i=i+1, return to step S201.

[0142] Step S207, using linear interpolation to calculate the initial correction coefficient m of the grayscale of the (i+2)th binding point i+2 .

[0143] Assume that the grayscale value of the i-th binding point is gray i , then the initial correction coefficient m of the grayscale of the (i+2)th binding point i+2 It is expressed as:

[0144]

[0145] Step S208: Calculate the initial correction coefficient m of the grayscale of the (i+1)th binding point by linear interpolation method i+1 , which is expressed as:

[0146]

[0147] Step S209: Calculate the initial correction coefficient m of the grayscale of the i-th binding point by linear interpolation method i , which is expressed as:

[0148]

[0149] Among them, step S207 to step S209 indicate that when the initial correction coefficient m0 ​​of the grayscale of a certain binding point is an abnormal value, the initial correction coefficient m0 ​​of the grayscale of the binding point is calculated by linear interpolation, and the original initial correction coefficient is replaced by the calculation result of linear interpolation.

[0150] Step S210, end the inspection.

[0151] Combination of the above Figures 1 to 4 The invention describes a process of pre-debugging each binding point grayscale under each display brightness interval in the first debugging stage to obtain an initial correction coefficient m0, and then performing a second stage debugging on the display module, wherein the display module includes multiple display brightness intervals, each display brightness interval corresponds to a second conversion relationship, and each display brightness interval includes multiple binding point grayscales. The gamma debugging method includes: for any display brightness interval, using the second conversion relationship corresponding to the display brightness interval, sequentially adjusting the first gamma register value of each binding point grayscale in the display brightness interval to obtain the first gamma register value of each binding point grayscale that makes the brightness and chromaticity of the display module meet the first brightness and chromaticity index.

[0152] Optional, please refer to Figure 5 , Figure 5 This is a flow chart for performing gamma debugging on any display brightness interval in the second debugging stage, such as Figure 5 As shown, the gamma debugging method provided by the embodiment of the present disclosure includes the following steps:

[0153] Step S301, setting the customer standard for this display brightness range, the customer standard includes but is not limited to the reference brightness and chromaticity of each binding point grayscale in the display brightness range, the allowable error threshold during the debugging process, that is, the first brightness and chromaticity index or the second brightness and chromaticity index.

[0154] Step S302, get the grayscale of the i-th binding point and write it into the gamma register value.

[0155] Step S303, detecting whether the brightness and chromaticity of the display module meets the first brightness and chromaticity index when the display module uses the first gamma register value for display, wherein the first gamma register value is the current value of the gamma register of the display module. If the detection result is yes, execute step S306; if the detection result is no, execute step S304.

[0156] Among them, the current value of the gamma register refers to the value currently written in the gamma register. When the first debugging is performed in the second debugging stage, the first gamma register value is the initial gamma register value, that is, the register value written to the gamma register for the first time. When the i-th debugging is performed, the first gamma register value is the register value written for the i-th time.

[0157] In specific implementation, the initial gamma register value can be a value randomly set by the debugger or the gamma register value output during debugging in the first debugging phase. Usually, in order to speed up debugging and shorten the debugging cycle, the initial gamma register value is the gamma register value output during the first debugging phase.

[0158] Assuming that the embodiment of the present disclosure is debugging for a certain display brightness interval of the binding point grayscale 3, the first gamma register value at this time represents the value currently written in the gamma register of the binding point grayscale 3. Assuming that the first gamma register value is the value written into the gamma register for the i-th time, the first gamma register value Reg i Represented as Reg i =(R i ,G i ,B i ), when determining whether the current first gamma register value meets the customer standard, the display module uses the first gamma register value (R i ,G i ,B i ) lights up the display module, and uses an optical device to measure the brightness and chromaticity of the display module at this time, and then determines whether the measured brightness and chromaticity meets the first brightness and chromaticity index.

[0159] The first brightness and chromaticity index is determined according to the customer standard. Specifically, the customer standard specifies the reference brightness and chromaticity of the display module at different binding point grayscales in different display brightness ranges. In specific implementation, when the error between the brightness and chromaticity of the display module and the reference brightness and chromaticity is within a certain range, it can be determined that the display module meets the customer standard.

[0160] Optionally, the step of detecting whether the brightness and chromaticity of the display module meets the first brightness and chromaticity index when the display module uses the first gamma register value for display includes:

[0161] (21) measuring the current brightness and chromaticity of the display module when displaying using the first gamma register value;

[0162] (22) determining whether an error between the current brightness and chromaticity and a reference brightness and chromaticity is less than a first error threshold, and determining that the brightness and chromaticity of the display module meets a first brightness and chromaticity index when the determination result is yes.

[0163] Exemplarily, the first brightness and chromaticity index indicates that the error between the brightness and chromaticity of the display module and the reference brightness and chromaticity is within 10%, that is, the first error threshold is 10%. At this time, if the error is within 10%, it meets the customer standard, and if the error exceeds 10%, it does not meet the customer standard.

[0164] In the disclosed embodiment, the second brightness and chromaticity index in the pre-debugging stage is more stringent than the first brightness and chromaticity index in the second debugging stage. For example, when the first brightness and chromaticity index indicates that the error between the brightness and chromaticity of the display module and the reference brightness and chromaticity is within 10%, the second brightness and chromaticity index may be that the error between the brightness and chromaticity of the display module and the reference brightness and chromaticity is within 1%. This is because in the pre-debugging stage, the measurement environment is more stable, and the display module can be considered to be working in a standard test environment, so the index requirements are more stringent at this time, while in the second debugging stage, the measurement environment (such as optical measurement equipment, display module temperature, etc.) has a larger error than that in the pre-debugging stage, so the index requirements are relatively loose at this time.

[0165] Step S304, calculate the first difference between the first gamma register value and the reference gamma register value, obtain an initial correction coefficient and use the initial correction coefficient to correct the first difference to obtain a first adjustment amount, the initial correction coefficient is used to represent the correlation between the actual adjustment amount and the theoretical adjustment amount, the actual adjustment amount is the change required for the first gamma register value to be adjusted to the target gamma register value, the theoretical adjustment amount is the change required for the first gamma register value to be adjusted to the reference gamma register value, the reference gamma register value is the theoretical gamma register value calculated based on the reference brightness and chromaticity, and the target gamma register value is the actual gamma register value when the brightness and chromaticity of the display module meet the first brightness and chromaticity index.

[0166] Among them, the reference gamma register value Reg t It is a theoretical value calculated by using the first conversion relationship, the second conversion relationship and the reference brightness and chromaticity required by the customer. Specifically, firstly, the reference brightness and chromaticity are converted into the reference spectral tristimulus value XYZ according to the first conversion relationship. t Then, according to the second conversion relationship, the reference spectrum tristimulus value XYZ t Convert to the reference gamma register value Reg t The first gamma register value Reg i and the reference gamma register value Reg t The first difference RGB D =XYZ D *T1 -1 =(XYZ t -XYZ i )*T1 -1 , using the initial correction coefficient m0 ​​to correct the first difference RGB DThe process of correcting and obtaining the first adjustment amount a is expressed as a=RGB D In the specific implementation, the initial correction coefficient m0 ​​is obtained by training in the first debugging stage and written into the display module. In the second debugging stage, the initial correction coefficient m0 ​​is used to adjust the first difference RGB D Make corrections.

[0167] Step S305, adjusting the first gamma register value by using the first adjustment amount, and writing the second gamma register value obtained after adjustment into the gamma register, and repeatedly executing the step of detecting whether the brightness and chromaticity of the display module when the display module uses the first gamma register value to display meets the first brightness and chromaticity index until the detection result is yes, that is, returning to step S303, and the first gamma register value at this time is the adjusted first gamma register value. Among them, adjusting the first gamma register value by using the first adjustment amount a can be expressed as Reg i+1 =Reg i +RGB D / m0.

[0168] Step S306, the gamma adjustment of the grayscale of the current binding point is completed, and the current gamma register value is output.

[0169] Step S307, judging whether i is less than the total number N of grayscales of the binding points, if the judgment result is yes, executing step S308, if the judgment result is no, executing step S309.

[0170] Step S308, setting i=i+1, returning to step S302, i.e. taking the next binding point grayscale, and continuing to debug the next binding point grayscale until the gamma debugging of all binding point grayscales in the display brightness range is completed.

[0171] Step S309, the grayscale adjustment of each binding point in the current display brightness interval is completed.

[0172] Compared with the related art, the gamma debugging method of the embodiment of the present invention adds a correction coefficient during the gamma debugging process. The correction coefficient can represent the correlation between the actual adjustment amount and the theoretical adjustment amount. During the gamma debugging process, the correction coefficient is used to correct the theoretical adjustment amount in real time, so that the theoretical adjustment amount changes in the direction of the actual adjustment amount. In this way, the problem of large deviations in the gamma register value due to uncertain factors such as optical device errors and ambient light can be prevented, and the gamma register value can be moved closer to the target gamma register value more quickly and accurately, thereby reducing the number of gamma debugging times, shortening the debugging cycle, and improving the production line capacity.

[0173] In a possible implementation, the step of detecting whether the brightness and chromaticity of the display module meets the first brightness and chromaticity index when the display module uses the first gamma register value for display in step S303 includes:

[0174] (31) measuring the current brightness and chromaticity of the display module when the display module uses the first gamma register value for display, and converting the current brightness and chromaticity into current spectral tristimulus values ​​according to the first conversion relationship.

[0175] (32) determining whether an error between the current spectral tristimulus value and the reference spectral tristimulus value is less than a first error threshold, and determining that the brightness and chromaticity of the display module meets a first brightness and chromaticity index when the determination result is yes.

[0176] When judging whether the display module meets the customer standards, the disclosed embodiment does not judge on the dimension of brightness and chromaticity, but converts the brightness and chromaticity into spectral tristimulus values ​​and judges on the dimension of spectral tristimulus values. Such a setting can improve the judgment accuracy and reduce the judgment error. Specifically, the brightness L value of the display module is relatively large, while the chromaticity coordinates x and y values ​​are usually very small. For details, please refer to Table 1. If the judgment is made on the dimension of brightness and chromaticity, it is easy to produce a large calculation error. On the dimension of spectral tristimulus values, the values ​​of spectral tristimulus values ​​X, Y, and Z are relatively large and the values ​​are relatively close. Judging on this dimension can reduce the calculation error and thus improve the judgment accuracy.

[0177] In a possible implementation manner, before the step of obtaining an initial correction coefficient and using the initial correction coefficient to correct the first difference to obtain the first adjustment amount, the step further includes:

[0178] Step S401, determining whether the adjustment step length of the gamma register is too small or too large, if the determination result is that the adjustment step length is too small, executing step S402, if the determination result is that the adjustment step length is too large, executing step S403.

[0179] The first adjustment amount a may represent the adjustment step of the gamma register. In an adjustment process, the larger the value of the first adjustment amount a is, the longer the adjustment step a is, and the smaller the value of the first adjustment amount a is, the smaller the adjustment step is.

[0180] When debugging a certain binding point grayscale, the debugging goal is to find a set of gamma register values ​​so that the brightness and chromaticity of the display module are close to the reference brightness and chromaticity. If the brightness and chromaticity measured for multiple times (for example, N times in a row, N is a natural number, and the value of N is generally 2, 3, 4, etc.) changes in the same direction (constantly decreasing or increasing) during the debugging process, it means that the adjustment step size is too small at this time, and the adjustment step size needs to be increased. If the brightness and chromaticity measured for multiple times in a row keeps fluctuating around the reference brightness and chromaticity, it means that the adjustment step size is too large, and the adjustment step size needs to be reduced. In this way, during the debugging process, it is possible to determine in real time whether the adjustment step size is too small or too large, and adjust the adjustment step size based on the judgment result, so that the debugged gamma register value can approach the reference gamma register value faster, speed up the adjustment speed, and shorten the adjustment cycle.

[0181] Optionally, the step of determining whether the adjustment step size of the gamma register is too small or too large includes:

[0182] (41) Acquire brightness and chromaticity measured multiple times continuously, each brightness and chromaticity being the brightness and chromaticity of the display module after adjusting the first gamma register value once.

[0183] (42) Determine whether the brightness and chromaticity measured continuously for multiple times are continuously increasing or continuously decreasing. If they are continuously increasing or continuously decreasing, it is determined that the adjustment step size is too small, and step S402 is executed.

[0184] (43) Determine whether the brightness and chromaticity measured continuously for multiple times fluctuate around the reference brightness and chromaticity. If so, it is determined that the adjustment step is too large, and step S403 is executed.

[0185] For any binding point grayscale, the debugging process is a process of finding the gamma register value, which can be expressed as: the initial gamma register value is written into the gamma register, and the brightness and chromaticity are measured by printing a picture. Assuming that the brightness and chromaticity measured for the first time is expressed as Lxy-1, and the brightness and chromaticity Lxy-1 does not meet the first brightness and chromaticity index, the gamma register value is adjusted and rewritten into the gamma register, and then the brightness and chromaticity is measured again. The brightness and chromaticity measured for the second time is expressed as Lxy-2. If the brightness and chromaticity Lxy-2 does not meet the first brightness and chromaticity index, the gamma register value is adjusted again, and the brightness and chromaticity is measured again. Repeat the above steps until the brightness and chromaticity meet the first brightness and chromaticity index.

[0186] In the debugging process, when it is determined that the brightness and chromaticity of the display module do not meet the first brightness and chromaticity index, a step of real-time judgment of the adjustment step is added, that is, step (41) is added to step (43). By judging whether the adjustment step is too large or too small and fine-tuning the adjustment step in real time, the reference gamma register value can be approached more quickly, the adjustment speed can be accelerated, and the adjustment cycle can be shortened.

[0187] Step S402: The initial correction coefficient is adjusted using a first weight coefficient, and the first adjustment amount increases when the adjusted initial correction coefficient corrects the first difference.

[0188] Exemplarily, the first weight coefficient is expressed as d1 (d1<1), and adjusting the initial correction coefficient m0 ​​using the first weight coefficient d1 can be expressed as m0=m0*d1. At this time, the first adjustment amount a will increase, that is, the adjustment step will increase.

[0189] Step S403: adjusting the initial correction coefficient by using the second weight coefficient, so that the first adjustment amount decreases when the first difference is corrected by the adjusted initial correction coefficient.

[0190] Exemplarily, the second weight coefficient is expressed as d2 (d2>1), and adjusting the initial correction coefficient m0 ​​using the second weight coefficient d2 can be expressed as m0=m0*d2. At this time, the first adjustment amount a will decrease, that is, the adjustment step will decrease.

[0191] It is understandable that, in the first debugging stage, the first weight coefficient and the second weight coefficient shown in steps S401 to S403 can also be used to adjust the preset correction coefficient in real time to speed up the debugging speed and shorten the debugging cycle.

[0192] In a possible implementation, the step of calculating a first difference between a first gamma register value and a reference gamma register value includes:

[0193] (51) obtaining the current brightness and color of the display module when the display module uses the first gamma register value for display;

[0194] (52) converting the current brightness and chromaticity into current spectral tristimulus values ​​and converting the reference brightness and chromaticity into reference spectral tristimulus values ​​according to a first conversion relationship, wherein the first conversion relationship represents a conversion relationship between brightness and chromaticity and spectral tristimulus values;

[0195] (53) Calculating the difference between the current spectral tristimulus value and the reference spectral tristimulus value and converting the difference into the first difference using a second conversion relationship, wherein the second conversion relationship represents a conversion relationship between a gamma register value and a spectral tristimulus value.

[0196] The specific implementation scheme for calculating the first difference can refer to the calculation process shown in Formula 3 and Formula 4, which will not be described in detail here.

[0197] Optionally, the gamma debugging method in the embodiment of the present disclosure can be applied to a driving unit of a display module, which includes a gamma register for storing gamma register values. The gamma debugging method in the embodiment of the present disclosure is used to debug a target gamma register value that meets the requirements and store it in the gamma register.

[0198] In a possible implementation, different display modules may have different numbers of gamma registers, such as 8 bits, 10 bits, 14 bits, etc. In order to make the gamma debugging method of the disclosed embodiment compatible with display modules with different numbers of bits, the gamma register value may be normalized during the debugging process. For example, gamma register values ​​with different numbers of bits are normalized to gamma register values ​​with 8 bits, and the normalization formula can be expressed as:

[0199]

[0200] Among them, depth represents the number of bits of the gamma register value of the display module. Correspondingly, after debugging to obtain the gamma register value of each binding point grayscale in each display brightness range of the display module, it is necessary to convert the gamma register value again into the number of bits corresponding to the display module.

[0201] Please refer to Table 3, which is a comparison table of the number of debugging times obtained by actually using the gamma debugging method of the disclosed embodiment (with correction coefficient) and the conventional gamma debugging method (without correction coefficient) to debug the grayscale of each binding point in a certain display brightness range of the display module to obtain the target gamma register value.

[0202] Table 3 Comparison of the number of gamma adjustments for a band with and without correction coefficients

[0203]

[0204]

[0205] It can be seen from Table 3 that after adding the correction coefficient m in the gamma debugging method, the total number of grayscale debugging of each binding point in a certain band is reduced, a total of 21 times. Calculated based on an average of 300ms each time, 6.3s of time can be saved. Assuming that there are 25 bands in total, the total debugging time of each display module can be saved by 157.5s.

[0206] Furthermore, by measuring the gamma debugging process of three OLED display modules, a comparison table of debugging times shown in Table 4 can be obtained.

[0207] Table 4 Comparison of the number of times multiple display modules are debugged when gamma is debugged with or without correction coefficients

[0208] Among them, each debugging includes the writing of a gamma register value, the measurement of an optical device, and the judgment and calculation of some other programs. Assuming that the time for writing a gamma register value is 102ms, and the time for the optical device to measure optical data is 25ms, it can be seen from Table 4 that compared with the conventional gamma debugging scheme, the gamma debugging method implemented in the present invention reduces the debugging of display module 1 by 396 times, saving 396 times*(102ms+25ms)=50292ms, reduces the debugging of display module 2 by 220 times, saving 220 times*(102ms+25ms)=27940ms, and reduces the debugging of display module 3 by 182 times, saving 182 times*(102ms+25ms)=23114ms.

[0209] Based on the same inventive concept, the second aspect of the present disclosure provides a computer-readable storage medium on which a computer program is stored, and when the program is executed by a processor, the steps of the gamma debugging method described above are implemented. In the specific implementation process, the computer storage medium may include: a Universal Serial Bus Flash Drive (USB), a mobile hard disk, a Read Only Memory (ROM), a Random Access Memory (RAM), a disk or an optical disk, and other storage media that can store program codes.

[0210] Based on the same inventive concept, the third aspect of the present disclosure provides a computer program product, including a computer program, which implements the steps of the gamma debugging method described above when executed by a processor. Since the principle of solving the problem by the above computer program is similar to that of the display driving method, the implementation of the above computer program can refer to the implementation of the display driving method, and the repeated parts will not be repeated.

[0211] The computer program product may employ any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination thereof. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with 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 (CDROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0212] Among them, the display module in the embodiment of the present disclosure can be an organic light emitting diode display module. It is understandable that the display module can also be set to other types according to actual needs. For example, the display module can also be a quantum dot light emitting diode (Quantum Dot Light Emitting Diode, referred to as QLED) display module or a micro light emitting diode (MicroLight Emitting Diode, referred to as Micro LED) display module, etc.

[0213] Obviously, the above embodiments of the present disclosure are merely examples for clearly illustrating the present disclosure, and are not limitations on the implementation methods of the present disclosure. For ordinary technicians in this field, other different forms of changes or modifications can be made on the basis of the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present disclosure are still within the protection scope of the present disclosure.

Claims

1. A gamma adjustment method, characterized in that: The following steps are involved: Detecting whether the brightness and chromaticity of the display module meets a first brightness and chromaticity index when the display module uses a first gamma register value for display, wherein the first gamma register value is a current value of a gamma register of the display module; If the detection result is no, a first difference between the first gamma register value and the reference gamma register value is calculated, an initial correction coefficient is obtained, and the first difference is corrected by using the initial correction coefficient to obtain a first adjustment amount, wherein the initial correction coefficient is used to represent the correlation between the actual adjustment amount and the theoretical adjustment amount, wherein the actual adjustment amount is the change amount required for adjusting the first gamma register value to the target gamma register value, and the theoretical adjustment amount is the change amount required for adjusting the first gamma register value to the reference gamma register value, wherein the reference gamma register value is a theoretical gamma register value calculated according to a reference brightness and chromaticity, and the target gamma register value is an actual gamma register value when the brightness and chromaticity of the display module meet the first brightness and chromaticity index; The first gamma register value is adjusted using the first adjustment amount, and the second gamma register value obtained after the adjustment is written into the gamma register, and the step of detecting whether the brightness and chromaticity of the display module meet the first brightness and chromaticity index when the display module uses the first gamma register value for display is repeatedly executed until the detection result is yes.

2. The gamma debugging method according to claim 1, characterized in that: The step of obtaining the initial correction coefficient also includes: Determining whether the adjustment step size of the gamma register is too small or too large; If the adjustment step is too small, the initial correction coefficient is adjusted using the first weight coefficient, and the first adjustment amount increases when the adjusted initial correction coefficient corrects the first difference; If the adjustment step is too large, the initial correction coefficient is adjusted using the second weight coefficient, and the first adjustment amount is reduced when the adjusted initial correction coefficient is used to correct the first difference.

3. The gamma debugging method according to claim 2, characterized in that: The step of determining whether the adjustment step size of the gamma register is too small or too large comprises: Acquire brightness and chromaticity measured multiple times continuously, each brightness and chromaticity is the brightness and chromaticity of the display module after adjusting the first gamma register value once; Determine whether the brightness and chromaticity measured for the plurality of consecutive times continuously increase or decrease, and if so, determine that the adjustment step length is too small; It is determined whether the brightness and chromaticity measured continuously for multiple times fluctuate around the reference brightness and chromaticity. If the determination result is yes, it is determined that the adjustment step is too large.

4. The gamma adjustment method according to any one of claims 1 to 3, characterized in that: The display module includes a plurality of display brightness intervals, each display brightness interval includes a plurality of binding point grayscales, each binding point grayscale corresponds to an initial correction coefficient, and the step of detecting whether the brightness and chromaticity of the display module meet the first brightness and chromaticity index when the display module uses the first gamma register value for display also includes: For any display brightness interval, pre-debugging is performed on each binding point grayscale within the display brightness interval in turn to determine an initial correction coefficient corresponding to the binding point grayscale.

5. The gamma debugging method according to claim 4, characterized in that: For any binding point grayscale within any display brightness range, the step of pre-debugging the binding point grayscale to determine the initial correction coefficient corresponding to the binding point grayscale includes: Detecting whether the brightness and chromaticity of the display module meets the second brightness and chromaticity index when the display module uses the third gamma register value for display, wherein the third gamma register value is the current value of the gamma register; If the detection result is yes, output the third gamma register value, and calculate the initial correction coefficient using the third gamma register value, the previous register value of the gamma register, and the reference gamma register value; If the detection result is no, calculating a second difference between the third gamma register value and the reference gamma register value, obtaining a preset correction coefficient, and using the preset correction coefficient to correct the second difference to obtain a second adjustment amount; The third gamma register value is adjusted using the second adjustment amount, and the fourth gamma register value obtained after adjustment is written into the gamma register, and the step of detecting whether the brightness and chromaticity of the display module meets the second brightness and chromaticity index when the display module uses the third gamma register value for display is repeatedly executed until the detection result is yes.

6. The gamma adjustment method according to claim 5, characterized in that: After the step of outputting the third gamma register value, the method further comprises: Determine whether the current debugging number is equal to the first value; If the current debugging number is greater than the first value, executing the step of calculating the initial correction coefficient using the third gamma register value, the previous register value of the gamma register, and the reference gamma register value; If the current debugging times is equal to the first value, the initial correction coefficient is calculated using the third gamma register value and the reference gamma register value, or the initial correction coefficient of the current binding point grayscale is interpolated using the initial correction coefficients of the binding point grayscales adjacent to the current binding point grayscale.

7. The gamma adjustment method according to claim 5, characterized in that: For any display brightness interval, after the step of sequentially pre-debugging each binding point grayscale within the display brightness interval to determine the initial correction coefficient corresponding to the binding point grayscale, the following step further comprises: Detect whether the initial correction coefficient corresponding to the grayscale of each binding point is an abnormal value; If the initial correction coefficient corresponding to the grayscale of any binding point is an abnormal value, the initial correction coefficient corresponding to the grayscale of the binding point is calculated using a linear interpolation method and the initial correction coefficient of the grayscale of the binding point is updated to a linear interpolation calculation result.

8. The gamma debugging method according to claim 1, characterized in that: The step of calculating a first difference between the first gamma register value and the reference gamma register value comprises: Obtaining the current brightness and color of the display module when the display module uses the first gamma register value for display; converting the current brightness and chromaticity into current spectral tristimulus values ​​and converting the reference brightness and chromaticity into reference spectral tristimulus values ​​according to a first conversion relationship, wherein the first conversion relationship represents a conversion relationship between brightness and chromaticity and spectral tristimulus values; The difference between the current spectral tristimulus value and the reference spectral tristimulus value is calculated and the difference is converted into the first difference using a second conversion relationship, wherein the second conversion relationship represents a conversion relationship between a gamma register value and a spectral tristimulus value.

9. The gamma debugging method according to claim 8, characterized in that: The step of detecting whether the brightness and chromaticity of the display module meets the first brightness and chromaticity index when the display module uses the first gamma register value for display comprises: Measuring the current brightness and chromaticity when the display module uses the first gamma register value for display, and converting the current brightness and chromaticity into current spectral tristimulus values ​​according to the first conversion relationship; It is determined whether the error between the current spectral tristimulus value and the reference spectral tristimulus value is less than a first error threshold, and when the determination result is yes, it is determined that the brightness and chromaticity of the display module meets the first brightness and chromaticity index.

10. The gamma debugging method according to claim 8, characterized in that: The display module includes a plurality of display brightness intervals, each display brightness interval corresponds to a second conversion relationship, each display brightness interval includes a plurality of binding point grayscales, and the gamma debugging method includes: For any display brightness range, the second conversion relationship corresponding to the display brightness range is used to adjust the first gamma register values ​​of each binding point grayscale in the display brightness range in turn to obtain the first gamma register values ​​of each binding point grayscale that make the brightness and chromaticity of the display module meet the first brightness and chromaticity index.

11. The gamma adjustment method according to claim 8, characterized in that: Before the step of calculating the first difference between the first gamma register value and the reference gamma register value, the step further includes: Writing the fifth gamma register value into the gamma register, obtaining the spectral tristimulus value of the display module when the display module uses the fifth gamma register value for display, the brightness of the display module when using the fifth gamma register value for display is greater than the brightness of the display module when using the maximum grayscale for display; The second conversion relationship is determined according to the fifth gamma register value and the spectral tristimulus value.

12. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the gamma debugging method according to any one of claims 1 to 11 are implemented.

13. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the gamma debugging method according to any one of claims 1 to 11 are implemented.

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