Display screen brightness control method, device, equipment and storage medium

Abstract

The application provides a display screen brightness control method and device, equipment and a storage medium, and relates to the technical field of integrated circuit design. The method comprises the following steps: during display of a display screen, when an instruction switch leading to flashing of the display screen is performed, target display data after brightness compensation is acquired; based on the target display data, a target brightness control signal for adjusting display brightness of an image of the display screen is generated; the target brightness control signal comprises a data signal and an EM signal; and the display screen is driven based on the target brightness control signal to display an image. By controlling the signal for driving the display screen, smooth switching of brightness is achieved, abnormal phenomena caused by sudden changes in brightness due to various reasons such as switching of refresh rate or under-screen fingerprint unlocking are avoided, the flashing problem is solved based on the driving IC end, overall resource consumption is reduced, and the effectiveness of compensation is improved.

Description

Technical Field

[0001] This application relates to the field of integrated circuit design technology, and more specifically, to a method, apparatus, device, and storage medium for controlling the brightness of a display screen. Background Technology

[0002] AMOLED displays employ a self-emissive technology, where each sub-pixel can emit light independently. The driver IC outputs a scan control signal to the display control circuit. When the display control circuit decodes and generates a row scan signal to select a pixel in a specific row on the display, the driver IC outputs a different data voltage to each sub-pixel, allowing different sub-pixels to exhibit different brightness levels. By controlling the data voltage of each row sequentially, the driver IC can display the entire screen image. Typically, the display data and brightness factor output by the driver IC are provided by the host (CPU or MCU-type processor).

[0003] Currently, for the screen flickering issue caused by previous in-display fingerprint unlocking, which stems from the change in full-screen background brightness due to the switching from multi-pulse to single-pulse EM (emission) signals, most solutions rely on the main controller's mask layer to keep the background brightness as constant as possible. There are no better solutions at the driver IC level. For the screen flickering caused by PWM (Pulse Width Modulation) interval refresh frequency switching, a long-V switching method is typically used, which increases the number of VFP rows to avoid abrupt changes in the EM duty cycle. However, this introduces many invalid rows, creating other issues that require optimization. Summary of the Invention

[0004] In view of the above, the purpose of this application is to provide a display brightness control method, device, equipment and storage medium. By acquiring the target display data after brightness compensation when switching instructions that cause screen flicker, a target brightness control signal for adjusting the display image brightness is generated, and the signal driving the display screen is controlled to make the brightness switch smoothly. The flicker problem is solved based on the driver IC, and abnormal phenomena such as brightness sudden changes caused by different refresh rates or under-display fingerprint unlocking are avoided, thereby solving the above-mentioned technical problems.

[0005] In a first aspect, embodiments of this application provide a display screen brightness control method, the method comprising: acquiring target display data after brightness compensation when switching instructions that cause the display screen to flicker; generating a target brightness control signal for adjusting the brightness of the image displayed on the display screen based on the target display data; wherein the target brightness control signal includes: a data signal and a scan control signal; and driving the display screen to display an image based on the target brightness control signal.

[0006] In the above implementation process, the target display data after brightness compensation is obtained when switching instructions that cause screen flicker, and then a target brightness control signal is generated to adjust the brightness of the image displayed on the screen. This controls the signal driving the screen, so that the brightness switches smoothly and avoids abnormal phenomena such as sudden brightness changes caused by different refresh rates or under-display fingerprint unlocking. The flicker problem is solved based on the driver IC, reducing overall resource consumption and improving the effectiveness of compensation.

[0007] Optionally, when switching instructions that cause screen flicker, obtaining the target display data after brightness compensation includes: changing the EM signal from multi-pulse to single-pulse when switching instructions that cause screen flicker; calculating the quantization ratio value of brightness compensation required when switching from a low brightness range to a high brightness range based on the brightness curve formula and the gamma curve formula; and multiplying the original value of the target display data by the quantization ratio value to obtain the target display data after brightness compensation.

[0008] In the above implementation process, by introducing a dimming approach based on EM changes to maintain constant brightness through voltage changes, the voltage is adjusted to compensate for the brightness value, thereby solving the problem of sudden brightness changes in the screen at the driver IC end and improving the compensation efficiency.

[0009] Optionally, the step of calculating the quantization ratio value of the brightness compensation required when switching from a low brightness range to a high brightness range based on the brightness curve formula and the gamma curve formula includes: calculating the current brightness based on the display brightness factor, maximum brightness value, and minimum brightness value of the display screen according to the brightness curve formula; and calculating the quantization ratio value based on the current brightness, display data, maximum display data value, and minimum display data value according to the gamma curve formula.

[0010] In the above implementation process, the final quantization ratio value and target display data are calculated step by step using the brightness curve formula and gamma curve formula. All calculations are performed after normalization, which reduces the amount of calculation and realizes the calculation of maintaining the original brightness through the brightness factor and ratio value, thereby improving the accuracy of brightness compensation.

[0011] Optionally, the step of calculating the quantization ratio value of the brightness compensation required when switching from a low brightness range to a high brightness range based on the brightness curve formula and the gamma curve formula includes: simultaneously solving the brightness curve formula and the gamma curve formula to construct an identity; eliminating the maximum and minimum brightness values ​​in the identity to obtain an intermediate equation; and setting the minimum display brightness factor and the minimum display data value in the intermediate equation to zero to obtain the quantization ratio value.

[0012] In the above implementation process, the final quantization ratio value and target display data are calculated by using the brightness curve formula and gamma curve formula simultaneously. All calculations are performed after normalization, which reduces the amount of calculation and enables the calculation of maintaining the original brightness through the brightness factor and ratio value, thereby improving the accuracy of brightness compensation.

[0013] Optionally, after calculating the quantization ratio value that needs to compensate for brightness when switching from a low brightness region to a high brightness region based on the brightness curve formula and the gamma curve formula, the method further includes: introducing a quantization ratio offset value to correct the quantization ratio value based on the brightness curve.

[0014] In the above implementation process, the theoretical quantization ratio values ​​calculated using the brightness curve formula and gamma curve formula are checked and corrected, which makes up for the defects of inaccurate compensation and improves the compensation accuracy.

[0015] Optionally, the reasons for screen flickering include: sudden changes in background brightness in the fingerprint area when performing fingerprint unlocking under the display screen.

[0016] In the above implementation process, by solving the screen flickering problem caused by sudden changes in the background brightness of the fingerprint area when performing fingerprint unlocking under the display screen, the application scope has been broadened and the universality of compensation has been improved.

[0017] Optionally, the screen flickering may be caused by switching refresh rates during the display process.

[0018] In the above implementation process, by solving the screen flickering problem caused by sudden brightness changes when the display refresh rate switches in application scenarios, the application scope has been broadened and the universality of compensation has been improved.

[0019] Secondly, embodiments of this application provide a display screen brightness control device, the device comprising: an acquisition module for acquiring target display data, used to acquire target display data after brightness compensation when switching instructions that cause screen flicker; an EM dimming module for generating a target brightness control signal to adjust the brightness of the image displayed on the display screen based on the target display data; wherein the target brightness control signal includes: a data signal and a scan control signal; and a display driving module for driving the display screen to display an image based on the target brightness control signal.

[0020] Thirdly, embodiments of this application also provide an electronic device, including: a processor and a memory, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the machine-readable instructions are executed by the processor to perform the steps of the above-described method.

[0021] Fourthly, embodiments of this application provide a storage medium storing a computer program, which, when executed by a processor, performs the steps of the above-described method.

[0022] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, specific embodiments are described below in conjunction with the accompanying drawings. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 A flowchart illustrating a display screen brightness control method provided in this application embodiment;

[0025] Figure 2 This application provides an embodiment of an EM dimming pulse diagram illustrating screen flickering caused by under-display fingerprint unlocking.

[0026] Figure 3 This application provides an embodiment of an EM dimming pulse diagram illustrating screen flicker caused by display refresh rate switching.

[0027] Figure 4 This is a schematic diagram of the functional modules of the display screen brightness control device provided in the embodiments of this application;

[0028] Figure 5 This is a block diagram of an electronic device that provides a display screen brightness control device according to an embodiment of this application.

[0029] Icons: 210 - Acquisition module; 220 - EM dimming module; 230 - Driver display module; 300 - Electronic device; 311 - Memory; 312 - Memory controller; 313 - Processor; 314 - Peripheral interface; 315 - Input / output unit; 316 - Display unit. Detailed Implementation

[0030] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0031] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. The terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. The terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0032] Before introducing the embodiments of this application, a brief introduction to the technical concepts involved in this application will be given first.

[0033] OLED displays are display devices made using organic light-emitting diodes (OLEDs). An OLED display has multiple pixels arranged on the panel, each pixel including an OLED component and multiple transistors configured to apply current to the OLED component. The transistors of the corresponding pixel are supplied with gate scan signals, emission signals, and source data signals to control the on / off state of the OLED component. In practical use of OLED display terminals, screen brightness adjustment, i.e., dimming, is required to make the screen brightness more suitable for the user's needs. Common dimming methods include gamma dimming, emission (em) signal dimming, and hybrid dimming that combines gamma and em dimming.

[0034] Frame rate: the source frame rate transmitted from the system; refresh rate: the corresponding refresh frequency on the screen. When the frame rate is greater than the refresh rate, there will be dropped frames during display; when the frame rate is less than the refresh rate, the screen refreshes more times, resulting in wasted power consumption.

[0035] Pulse Width Modulation (PWM): PWM is a clock control signal used to adjust the current in motors or other electrical equipment. Its pulse period can range from tens of seconds to microseconds. PWM actually represents a duty cycle (i.e., the percentage of high-level time in each signal cycle). Its amplitude can be DC or AC, while the width can be represented by a percentage value between 0 and 100%, where 100% means the high-level state of the signal will last for the entire signal cycle.

[0036] Gamma curve: A curve showing the relationship between different gray levels and brightness. Using 0-255 gray levels (grayscale values) as the X-axis and brightness as the Y-axis, the resulting curve is called the gamma curve. The reciprocal of the exponent of the power function is the gamma value. Typically, for Windows output display systems, the gamma value is 2.2, while for Apple's output display and printing systems, the gamma value is 1.8.

[0037] The inventors of this application have noted that when the driver IC outputs a scanning control signal to the display control circuit, and the display control circuit decodes and generates a row scanning signal to select a pixel in a certain row on the display screen, the driver IC outputs a different data voltage to each sub-pixel on the display screen. This allows different sub-pixels to exhibit different brightness levels. By controlling the data voltage of each row of the display screen line by line, the driver IC can achieve the purpose of displaying the entire screen image. The brightness control of AMOLED screens is divided into PWM dimming, DC dimming, or PWM+DC hybrid dimming. Among them, hybrid dimming is the mainstream dimming method nowadays, combining the advantages of both PWM dimming and DC dimming. Generally, a 30% to 50% brightness level is used as the dividing line, with PWM dimming used below the dividing line and DC dimming used above it.

[0038] There are several reasons why displays may flicker, but two are particularly common. Firstly, with the popularity of high refresh rate phones, a trade-off between higher refresh rates and lower power consumption has become necessary. Refresh rate switching is an inevitable application scenario. When refresh rate switching occurs within the PWM range, the inconsistent EM duty cycle at the boundary can cause sudden brightness changes. In the DC range, since EM is not a primary dimming factor, sudden brightness changes also occur. To avoid flickering caused by PWM range refresh rate switching, a long-V switching method is typically used, which increases the number of VFP rows to avoid sudden EM duty cycle changes. However, this introduces other optimization problems due to the added number of invalid rows (e.g., power consumption issues, resource consumption issues related to expanding the corresponding control bit width). Secondly, under-display fingerprint unlocking is very common. To ensure smooth fingerprint unlocking, it's necessary to minimize black bars when the fingerprint is triggered. If the trigger occurs in a high-brightness area (DC dimming zone), the black level is already minimal, requiring no special handling. If the trigger occurs in a low-brightness area (PWM dimming zone), the black level is greater, and the luminous emission control signal (EM signal) is multi-pulse, requiring a switch to single-pulse. EMpulse switching causes a change in overall screen brightness. Since the brightness within the fingerprint sensor is controlled independently, it's crucial to maintain a constant background brightness outside the fingerprint sensor. Current under-display fingerprint unlocking solutions address this issue of overall background brightness changes caused by the EM multi-pulse to single-pulse switching primarily using a main control layer to keep the background brightness as constant as possible; however, there is no better solution at the driver IC level. Therefore, this application provides a display brightness control method, apparatus, device, and storage medium, as described below.

[0039] Please see Figure 1 , Figure 1 This is a flowchart illustrating a display screen brightness control method provided in an embodiment of this application. The embodiments of this application are explained in detail below. The method includes steps 100, 120, and 140.

[0040] Step 100: When switching instructions that cause screen flickering, obtain the target display data after brightness compensation;

[0041] Step 120: Based on the target display data, generate a target brightness control signal to adjust the brightness of the image displayed on the screen; wherein, the target brightness control signal includes: a data signal and a scan control signal;

[0042] Step 140: Drive the display screen to display the image based on the target brightness control signal.

[0043] For example, the entire display framework of an AMOLED display system can generally include three parts: a CPU / MCU-controlled image display module, a driver IC, and an AMOLED display. The driver IC is responsible for generating corresponding data and EM signals to push the image onto the AMOLED display for display when the CPU / MCU sends display data (display data, display brightness factor). Simultaneously, it can control the output of the data and EM signals based on the display brightness factor, thereby controlling the brightness of the displayed image. Therefore, the target display data can be: the target brightness value obtained by calculating the display data of the area with a sudden brightness change using a brightness compensation value when switching instructions that cause screen flicker.

[0044] Optionally, when screen flickering occurs, an EM dimming method can be used, which, based on fixed data (i.e., keeping the current constant), changes the time the current passes through the OLED device within one frame (em duty), and combines this with a high refresh rate to visually change the display brightness. After calculating the brightness compensation value, the target display data after brightness compensation is obtained, and a target brightness control signal, namely the data signal and the EM signal, is generated to adjust the brightness of the image displayed on the screen. The image is then pushed onto the AMOLED display for display through the data signal and the EM signal, thereby controlling the brightness of the image display and overcoming the problem of sudden brightness changes caused by screen flickering.

[0045] By acquiring the target display data after brightness compensation when the display screen flickers, a target brightness control signal is generated to adjust the brightness of the image displayed on the display screen. This signal controls the signal driving the display screen, ensuring smooth brightness switching and avoiding abnormal phenomena such as sudden brightness changes caused by different refresh rates or under-display fingerprint unlocking. By solving the flickering problem at the driver IC level, the overall resource consumption is reduced and the effectiveness of compensation is improved.

[0046] In one embodiment, step 100 may include steps 101, 102, and 103.

[0047] Step 101: When switching instructions that cause screen flickering, change the EM signal from multi-pulse to single-pulse;

[0048] Step 102: Based on the brightness curve formula and gamma curve formula, calculate the quantization ratio value of the brightness compensation required when switching from the low brightness range to the high brightness range;

[0049] Step 103: Multiply the original value of the target display data by the quantization ratio value to obtain the target display data after brightness compensation.

[0050] For example, multiple pulses can be 4 pulses, 8 pulses, 16 pulses, etc. Optionally, the EM signal is changed from 4 pulses (multiple pulses) to 1 pulse (single pulse), where the width of the target 1 pulse can be set as a prerequisite for calculating the brightness compensation value. When the EM changes from 4-pulse to 1-pulse, that is, in the brightness curve, it changes from a low brightness area (PWM dimming area) to a high brightness area (DC dimming area). This high brightness is called the reference brightness. This reference brightness is in the DC range, and the display brightness needs to be reduced by increasing the data voltage to restore it to the brightness of the original 4 pulses. Since data and voltage are negatively correlated: the larger the data, the lower the voltage and the higher the brightness, increasing the data voltage corresponds to multiplying the original data value by a quantization ratio value between 0 and 1, mapping it to a new data. The new data is smaller than the original data, so the corresponding output voltage will increase, the brightness will decrease, and thus restore the original brightness. The quantization ratio value is calculated based on the brightness curve formula and the gamma curve formula. By incorporating voltage changes based on EM variations to maintain constant brightness, the voltage is adjusted to compensate for brightness values, thus resolving the issue of sudden brightness changes caused by screen flicker at the driver IC level and improving compensation efficiency.

[0051] In one embodiment, step 102 may include steps 1021 and 1022.

[0052] Step 1021: Based on the brightness curve formula, calculate the current brightness according to the display brightness factor, maximum brightness value, and minimum brightness value of the display screen;

[0053] Step 1022: Based on the gamma curve formula, calculate the quantization ratio value according to the current brightness, display data, maximum display data value, and minimum display data value.

[0054] For example, to calculate the quantization ratio, the current brightness can be calculated first using the brightness curve formula, and then substituted into the gamma curve formula to calculate the quantization ratio.

[0055] From the brightness curve formula, we can see that:

[0056]

[0057] In the formula, y lv The current brightness is denoted by 'a', where 'a' is the exponential factor and 'x' is the exponential factor. dbv For brightness factor, These are the minimum and maximum values ​​of the brightness factor, respectively. These represent the maximum and minimum values ​​of brightness, respectively. Taking a=1 as an example, the brightness curve is a normalized linear curve, and the host computer can obtain the current brightness y through the brightness factor.lv The formula for obtaining the target data (target display data) can be expressed as: Where, x gray For the target data value, This represents the maximum value of the data.

[0058] From the gamma curve formula, we know that:

[0059]

[0060] In the formula, x gray For the target data value, These are the minimum and maximum values ​​of the original data, respectively. available The host computer can calculate the ratio by assigning maximum and minimum brightness values, and then calculate the target display data value.

[0061] By using the brightness curve formula and gamma curve formula to gradually calculate the final quantization ratio value and target display data, all calculations are performed after normalization, reducing the amount of computation and enabling the calculation to maintain the original brightness through the brightness factor and ratio value, thus improving the accuracy of brightness compensation.

[0062] In one embodiment, step 102 may further include steps 1023, 1024 and 1025.

[0063] Step 1023: Combine the luminance curve formula and the gamma curve formula to construct an identity;

[0064] Step 1024: Eliminate the maximum and minimum brightness values ​​in the identity to obtain the intermediate equation;

[0065] Step 1025: Set the minimum value of the display brightness factor and the minimum value of the display data in the intermediate equation to zero to obtain the quantization ratio value.

[0066] For example, to calculate the quantization ratio, one can first calculate the current brightness using the brightness curve formula, and then substitute it into the gamma curve formula to calculate the quantization ratio. In actual driver IC design, bit width can be reserved as appropriate, considering the application scenario, to meet practical needs. Since the driver IC cannot preset the brightness value, the quantization ratio can also be calculated to obtain the target display data.

[0067] Establish a simultaneous equation using the formulas for the brightness curve and the gamma curve:

[0068]

[0069]

[0070] From the above two formulas, let When they are equal, or only slightly different or approximately equal, we can obtain an intermediate equation for the identity:

[0071]

[0072] The result of the transformation is:

[0073]

[0074] Depend on Or close to 0, which can be considered as 0, and thus we get:

[0075]

[0076] This leads to the ratio value:

[0077] The final quantization ratio value and target display data are calculated by simultaneously using the brightness curve formula and the gamma curve formula. All calculations are performed after normalization, which reduces the amount of computation and enables the calculation to maintain the original brightness through the brightness factor and ratio value, thereby improving the accuracy of brightness compensation.

[0078] In one embodiment, after step 102, step 103 is also included.

[0079] Step 103: Based on the brightness curve, introduce a quantization ratio offset value to correct the quantization ratio value.

[0080] For example, considering that the actual brightness curve is not absolutely ideal and may have slight dips or bulges, the theoretical ratio value calculated according to steps 1021-1022 or steps 1023-1025 will deviate in actual use, ultimately manifesting as brightness deviation. Therefore, a ratio_offset value (quantization ratio offset value) is introduced to appropriately correct the theoretical ratio value. When the brightness curve tends to deviate downwards, the exponent 'a' of the power function is larger than the theoretical value, and the final ratio = ratio_ideal - ratio_offset; when the brightness curve tends to deviate upwards, the exponent 'a' of the power function is smaller than the theoretical value, and the final ratio = ratio_ideal + ratio_offset. By checking and correcting the theoretical quantization ratio value calculated using the brightness curve formula and gamma curve formula, the defect of inaccurate compensation is compensated for, and the compensation accuracy is improved.

[0081] In one embodiment, the screen flickering may be caused by a sudden change in the background brightness of the fingerprint area when fingerprint unlocking is performed under the display.

[0082] For example, when using an in-display fingerprint sensor to trigger fingerprint unlocking, it is required to reduce black bars. If the trigger occurs in a high-brightness area (DC dimming zone), the black bars are already minimal and no special processing is needed. If the trigger occurs in a low-brightness area (PWM dimming zone), the black bars are greater, and the luminous emission control signal (EM) is multi-pulse, requiring a switch to single-pulse. EM pulse switching causes a change in the overall screen brightness. Since the brightness within the fingerprint sensor is controlled separately, it is necessary to ensure that the background brightness outside the fingerprint sensor remains unchanged. Existing technologies generally use a master control layer to solve this problem. The brightness control method provided in this application calculates the brightness relationship through a host computer and sends a new display image to the driver IC during fingerprint unlocking. This eliminates the need for host computer layer processing to control the background brightness. It is a novel method to solve this problem from the driver IC side, and can resolve the issue of sudden background brightness changes (flickering) during fingerprint unlocking in the low-brightness EM zone.

[0083] Regarding the issue of the PWM dimming range entering the fingerprint screen, taking the EM 4-pulse output in normal display mode as an example, in under-display fingerprint unlocking mode (FOD mode), in order to reduce the black area and ensure smooth unlocking, the EM switches from multiple pulses to a single pulse. This causes the background image outside the fingerprint sensor, i.e., the non-fingerprint area, to brighten, which the human eye perceives as screen flickering during fingerprint unlocking. Figure 2 As shown, the voltage pulse changes of the EM signal (EM1 and EM2), quantization ratio value Ratio, voltage, and brightness curve (Lv) are illustrated in two modes. EM signals change from 4 pulses to 1 pulse, where the width of the target 1 pulse can be flexibly set according to actual applications (e.g., the width of the 1 pulse changes for EM1 and EM2 is different). Based on the idea of ​​introducing voltage changes while maintaining constant brightness based on EM changes, the voltage can be adjusted and brightness compensated through steps 101-103. Specifically, the quantization ratio value can be calculated using steps 1021-1022 or steps 1023-1025, and further corrected using step 104 to calculate the target display data value. Based on the target display data value, a data signal and EM signal are generated to adjust the brightness of the displayed image and drive the display screen, achieving the effect of flicker brightness compensation. By solving the flicker problem caused by sudden changes in background brightness outside the fingerprint sensor during fingerprint unlocking, the application scope is broadened and the versatility of compensation is improved.

[0084] In one embodiment, the screen flickering may be caused by switching refresh rates during the display process.

[0085] For example, when the display refresh rate switching occurs within the PWM interval, an inconsistency in the EM duty cycle exists at the boundary, leading to sudden brightness changes. In the DC interval, however, since EM is not a primary dimming factor, this brightness change issue does not occur. Existing conventional methods to address screen flickering caused by PWM interval refresh rate switching employ a long-V switching method that increases the number of VFP rows. The brightness control method provided in this application, without adding invalid rows, can smoothly switch brightness by controlling the signal driving the display during refresh rate switching, thus resolving the PWM interval refresh rate switching flickering problem.

[0086] Regarding the issue of EM interval refresh rate switching, taking EM 4-pulse output at both 120Hz and 60Hz (two different refresh rates) as an example, the EM proportion is equal at 120Hz and 60Hz. At the moment of refresh rate switching, the EM proportion may differ from the previous and subsequent values, resulting in a higher brightness across the entire frame, i.e., a white screen flicker, which only returns to normal in the next frame. For example... Figure 3 The diagram illustrates the voltage pulse changes of the frame, EM signals (EM1 and EM2), quantization ratio, data (Data_in and Data_out), and brightness curve (Lv). EM signals change from 4 pulses to 1 pulse, where the width of the target 1 pulse can be flexibly set according to the actual application (e.g., the widths of EM1 and EM2 changing to 1 pulse are different). Based on the idea of ​​introducing voltage changes while maintaining constant brightness according to EM changes, the voltage can be adjusted and brightness compensated through steps 101-103. Specifically, the quantization ratio can be calculated using steps 1021-1022 or 1023-1025, and further corrected using step 104 to calculate the target display data value. Based on the target display data value, a data signal and EM signal are generated to adjust the brightness of the displayed image, driving the display screen to achieve the effect of flicker brightness compensation. By solving the flicker problem caused by sudden brightness changes when the display refresh rate switches, the application scope is broadened and the versatility of compensation is improved.

[0087] Please see Figure 4 , Figure 4 This is a schematic diagram illustrating the module functions of a display screen brightness control device provided in an embodiment of this application. The device includes: an acquisition module 210, an EM dimming module 220, and a display driving module 230.

[0088] The acquisition module 210 is used to acquire target display data module, and is used to acquire target display data after brightness compensation when the display screen flickers;

[0089] The EM dimming module 220 is used to generate a target brightness control signal for adjusting the brightness of the image displayed on the display screen based on the target display data; wherein, the target brightness control signal includes: a data signal and an EM signal;

[0090] The drive display module 230 is used to drive the display screen to display images based on the target brightness control signal.

[0091] Optionally, the acquisition module 210 can be used for:

[0092] When switching instructions that cause the display to flicker, the EM signal is changed from a multi-pulse to a single pulse;

[0093] Based on the luminance curve formula and gamma curve formula, calculate the quantization ratio value of the luminance compensation required when switching from a low luminance range to a high luminance range.

[0094] Multiply the original value of the target display data by the quantization ratio value to obtain the brightness-compensated target display data.

[0095] Optionally, the acquisition module 210 can be used for:

[0096] Based on the brightness curve formula, the current brightness is calculated according to the display brightness factor, maximum brightness value, and minimum brightness value of the display screen;

[0097] Based on the gamma curve formula, the quantization ratio value is calculated according to the current brightness, display data, maximum display data value, and minimum display data value.

[0098] Optionally, the acquisition module 210 can be used for:

[0099] By combining the formulas for the brightness curve and the gamma curve, an identity can be constructed.

[0100] Eliminate the maximum and minimum brightness values ​​in the aforementioned identity to obtain an intermediate equation;

[0101] By setting the minimum value of the display brightness factor and the minimum value of the display data in the intermediate equation to zero, the quantization ratio value is obtained.

[0102] Optionally, the acquisition module 210 can be used for:

[0103] Based on the brightness curve, a quantization ratio offset value is introduced to correct the quantization ratio value.

[0104] Optionally, the reasons for screen flickering include: sudden changes in background brightness in the fingerprint area when performing fingerprint unlocking under the display screen.

[0105] Optionally, the screen flickering may be caused by switching refresh rates during the display process.

[0106] Please see Figure 5 , Figure 5 This is a block diagram of an electronic device. The electronic device 300 may include a memory 311, a memory controller 312, a processor 313, a peripheral interface 314, an input / output unit 315, and a display unit 316. Those skilled in the art will understand that... Figure 5 The structure shown is for illustrative purposes only and does not limit the structure of the electronic device 300. For example, the electronic device 300 may also include components that are more... Figure 5 The more or fewer components shown, or having the same Figure 5 The different configurations shown.

[0107] The aforementioned memory 311, memory controller 312, processor 313, peripheral interface 314, input / output unit 315, and display unit 316 are electrically connected directly or indirectly to achieve data transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses or signal lines. The aforementioned processor 313 is used to execute executable modules stored in the memory.

[0108] The memory 311 can be, but is not limited to, Random Access Memory (RAM), Read Only Memory (ROM), Programmable Read-Only Memory (PROM), Erasable Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM), etc. The memory 311 stores programs, and the processor 313 executes these programs upon receiving execution instructions. The methods executed by the electronic device 300, as defined in any embodiment of this application, can be applied to or implemented by the processor 313.

[0109] The aforementioned processor 313 may be an integrated circuit chip with signal processing capabilities. The processor 313 may be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it may also be a digital signal processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor may be a microprocessor or any conventional processor.

[0110] The peripheral interface 314 described above couples various input / output devices to the processor 313 and the memory 311. In some embodiments, the peripheral interface 314, the processor 313, and the memory controller 312 can be implemented in a single chip. In other instances, they can be implemented by separate chips.

[0111] The input / output unit 315 described above is used to provide user input data. The input / output unit 315 may be, but is not limited to, a mouse and keyboard.

[0112] The aforementioned display unit 316 provides an interactive interface (e.g., a user interface) for the user to reference between the electronic device 300 and the user. In this embodiment, the display unit 316 may be a liquid crystal display (LCD) or a touch screen display. The LCD or touch screen display can show the process of the processor executing the program.

[0113] The electronic device 300 in this embodiment can be used to perform the various steps in the various methods provided in the embodiments of this application.

[0114] Furthermore, this application embodiment also provides a storage medium storing a computer program, which is executed by a processor to perform the steps in the above method embodiments.

[0115] The computer program product of the above-described method provided in this application includes a storage medium storing program code. The instructions included in the program code can be used to execute the steps in the above-described method embodiments. For details, please refer to the above-described method embodiments, which will not be repeated here.

[0116] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the displayed or discussed mutual couplings, direct couplings, or communication connections may be through some communication interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms. The functional modules in the embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0117] It should be noted that if the function is implemented as a software module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0118] In this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, without necessarily requiring or implying any such actual relationship or order between these entities or operations.

[0119] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method for controlling the brightness of a display screen, characterized in that, The method includes: When switching commands that cause screen flickering, obtain the target display data after brightness compensation; Based on the target display data, a target brightness control signal is generated to adjust the brightness of the image displayed on the display screen; wherein, the target brightness control signal includes: a data signal and an EM signal; The display screen is driven to display images based on the target brightness control signal; The step of acquiring the target display data after brightness compensation during the instruction switching that causes screen flickering includes: When switching instructions that cause the display to flicker, the EM signal is changed from a multi-pulse to a single pulse; Based on the luminance curve formula and gamma curve formula, calculate the quantization ratio value of the luminance compensation required when switching from a low luminance range to a high luminance range. Multiply the original value of the target display data by the quantization ratio value to obtain the brightness-compensated target display data.

2. The method according to claim 1, characterized in that, The calculation of the quantization ratio value for brightness compensation required when switching from a low-brightness region to a high-brightness region, based on the brightness curve formula and gamma curve formula, includes: Based on the brightness curve formula, the current brightness is calculated according to the display brightness factor, maximum brightness value, and minimum brightness value of the display screen; Based on the gamma curve formula, the quantization ratio value is calculated according to the current brightness, display data, maximum display data value, and minimum display data value.

3. The method according to claim 1, characterized in that, The calculation of the quantization ratio value for brightness compensation required when switching from a low-brightness region to a high-brightness region based on the brightness curve formula and gamma curve formula includes: By combining the formulas for the brightness curve and the gamma curve, an identity can be constructed. Eliminate the maximum and minimum brightness values ​​in the aforementioned identity to obtain an intermediate equation; By setting the minimum value of the display brightness factor and the minimum value of the display data in the intermediate equation to zero, the quantization ratio value is obtained.

4. The method according to claim 1, characterized in that, After calculating the quantization ratio value of the brightness compensation required when switching from a low brightness region to a high brightness region based on the brightness curve formula and gamma curve formula, the method further includes: Based on the brightness curve, a quantization ratio offset value is introduced to correct the quantization ratio value.

5. The method according to any one of claims 1-4, characterized in that, The reasons for screen flickering include: sudden changes in background brightness in the fingerprint area when unlocking the screen with a fingerprint.

6. The method according to any one of claims 1-4, characterized in that, The reasons for screen flickering include: switching refresh rates during screen display.

7. A display screen brightness control device, characterized in that, The device includes: The acquisition module is used to acquire target display data, which is used to acquire the target display data after brightness compensation when switching instructions that cause the display screen to flicker. An EM dimming module is used to generate a target brightness control signal to adjust the brightness of the image displayed on the screen based on the target display data; wherein, the target brightness control signal includes: a data signal and a scan control signal; The drive display module is used to drive the display screen to display images based on the target brightness control signal; Specifically, the acquisition module is used for: When switching instructions that cause the display to flicker, the EM signal is changed from a multi-pulse to a single pulse; Based on the luminance curve formula and gamma curve formula, calculate the quantization ratio value of the luminance compensation required when switching from a low luminance range to a high luminance range. Multiply the original value of the target display data by the quantization ratio value to obtain the brightness-compensated target display data.

8. An electronic device, characterized in that, include: The processor and memory, wherein the memory stores machine-readable instructions executable by the processor, wherein when the electronic device is running, the machine-readable instructions are executed by the processor to perform the steps of the method as described in any one of claims 1 to 6.

9. A storage medium, characterized in that, The storage medium stores a computer program, which, when executed by a processor, performs the steps of the method as described in any one of claims 1 to 6.

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