A method and system for displaying brightness on a high-precision advertising screen

Abstract

This invention relates to the field of display screen technology, specifically to a high-precision advertising screen brightness display method and system, comprising: acquiring an input image to be displayed; performing size regularization on the input image; reading red channel values, green channel values, and blue channel values ​​from pixel buffer data; calculating the average brightness of the input image and determining the brightness category; reading the device operating status information of the advertising screen terminal and determining the current display mode; calling a parameter lookup table and determining a parameter combination based on the brightness category and display mode, the parameter combination including tone mapping brightness control parameters, detail enhancement parameters, and panel brightness control values; performing global tone mapping compensation processing based on the tone mapping brightness control parameters to obtain an intermediate image; performing unsharpening masking processing on the intermediate image based on the detail enhancement parameters to obtain a compensated image; writing the compensated image to the display buffer link and sending the panel brightness control values ​​to the display driver link to adjust the power supply voltage of the display panel.

Description

Technical Field

[0001] This invention relates to the field of display screen technology, and in particular to a high-precision advertising screen brightness display method and system. Background Technology

[0002] With the widespread application of high-end Android advertising screen terminals in commercial displays, public information dissemination, and long-term continuous playback scenarios, the displayed content not only needs to have good brightness and visual clarity, but also needs to consider the terminal's energy consumption control, operational stability, and panel lifespan. Especially under conditions of high dynamic range images, strong ambient light, or different playback times, existing advertising screen display solutions often face two contradictions: on the one hand, to ensure brightness and visibility, the display drive intensity is usually increased, resulting in higher power consumption and heat load; on the other hand, simply reducing the drive intensity to save energy can easily lead to a decline in image shadow detail, local detail, and overall visual quality. Among existing related technologies, although there has been research on low-power control, color transformation, or dynamic voltage scaling for OLED / AMOLED displays, there are still problems such as loss of image detail, decreased visual satisfaction, and difficulty in balancing energy saving control and display quality for displayed content after dynamic range compression. Therefore, a technical solution that can adaptively adjust the display for different brightness content and different operating states is still needed. Summary of the Invention

[0003] In view of the above technical problems, the present invention provides a high-precision advertising screen brightness display method and system, which aims to solve the problems of existing advertising screens when displaying images with different brightness distributions, such as difficulty in balancing display effect and energy consumption control, easy degradation of local details and contrast after brightness adjustment, and lack of adaptive optimization for device operating status.

[0004] Other features and advantages of the invention will become apparent from the following detailed description, or may be learned in part by practice of the invention.

[0005] According to one aspect of the present invention, a high-precision advertising screen brightness display method is proposed, the method comprising the steps of: The input image to be displayed is obtained, the size of the input image is normalized, and the red channel value, green channel value and blue channel value of each pixel are read from the pixel buffer data corresponding to the input image. The average brightness of the input image is calculated based on the red channel value, the green channel value and the blue channel value, and the brightness category is determined. Read the device operating status information of the advertising screen terminal, and determine the current display mode based on the device operating status information; Call the parameter lookup table and determine the parameter combination corresponding to the input image based on the brightness category and the display mode. The parameter combination includes at least tone mapping brightness control parameters, detail enhancement parameters and panel brightness control values. The input image is subjected to global tone mapping compensation processing according to the tone mapping brightness control parameters. The global tone mapping compensation processing includes linear scaling of the input brightness and global brightness mapping constrained by the maximum expressible brightness of the display panel on the linearly scaled input brightness to obtain an intermediate image. The intermediate image is subjected to unsharpening masking processing based on the detail enhancement parameters to enhance the local contrast and details of the intermediate image, thereby obtaining a compensated image; The compensated image is written to the display buffer link, and the panel brightness control value is sent to the display driver link to adjust the power supply voltage of the display panel of the advertising screen terminal while displaying the compensated image.

[0006] Furthermore, the pixel buffer data corresponding to the input image after display compositing is obtained, and the input image is transmitted to the frame buffer hardware abstraction layer in the form of a pixel buffer via Surfaceflinger and HWComposer. The frame buffer hardware abstraction layer reads the red channel value, green channel value, and blue channel value of each pixel by accessing the pixel buffer. The input image is normalized to a display size that matches the display resolution of the target advertising screen panel, and the average brightness is calculated based on the normalized pixel data, so that the input image corresponds to the predetermined brightness category in the parameter lookup table.

[0007] Furthermore, the device operating status information includes at least one of ambient light information, panel temperature information, current time period information, continuous running duration information, playback task information, and preset display strategy information; after collecting the device operating status information, the advertising screen terminal is determined to be in one of the following display modes: high performance mode, balanced mode, energy-saving mode, thermal protection mode, and lifespan protection mode, wherein different display modes correspond to different parameter selection strategies and different panel drive control intensities.

[0008] Furthermore, the parameter lookup table is established in the following way: Training images covering different average brightness distributions are selected, and multiple sets of candidate parameter combinations are configured for each training image. Each set of candidate parameter combinations includes different tone mapping brightness control parameters, detail enhancement parameters, and panel brightness control values. Subjective visual evaluation is performed on the resulting image after processing with each set of candidate parameter combinations relative to the corresponding reference image, and the display energy consumption result relative to the baseline display state is measured simultaneously; the parameter lookup table is established according to the brightness category and the display mode, so that each table entry corresponds to the target parameter combination that takes into account subjective visual satisfaction, display energy consumption effect, panel thermal stability and long-term operating life requirements.

[0009] Furthermore, when the device operation status information indicates that the advertising screen terminal is in a key playback period, with strong ambient light, high viewing demand, or high playback task priority, the display mode is determined to be a high performance mode, and the target parameter combination that meets the control requirements for display energy consumption effect is selected from the candidate parameter combinations with higher subjective visual scores. When the device operating status information indicates that the advertising screen terminal is in normal playback state, the display mode is determined to be balanced mode, and the target parameter combination that maintains a balance between human eye perception effect and display energy consumption effect is selected. When the device operation status information indicates that the advertising screen terminal is in a low attention playback period, has a high continuous operating load, has an increased panel temperature, or has a preset energy-saving strategy in effect, the display mode is determined to be energy-saving mode, thermal protection mode, or life protection mode, and the target parameter combination that meets the subjective visual satisfaction requirements is selected from the candidate parameter combinations that are superior in display energy consumption effect, panel thermal stability, or long-term operating life.

[0010] Furthermore, acquiring the intermediate image specifically includes: First, the logarithmic average of the input brightness of the input image is calculated. Then, a linear scaling factor is determined based on the logarithmic average of the input brightness and the tone mapping brightness control parameter. The input brightness of each pixel is linearly scaled using the linear scaling factor to obtain an intermediate brightness. Then, the intermediate brightness is input to the brightness mapping function to obtain the output brightness within the brightness range that the advertising screen terminal can express. The pixel values ​​of the input image are compensated based on the output brightness to generate the intermediate image.

[0011] Furthermore, acquiring the compensated image specifically includes: A high-pass filter is applied to the intermediate image to extract edge and detail information. The high-pass filter result is weighted using the detail enhancement parameters, and the weighted high-pass filter result is superimposed on the intermediate image to obtain the compensated image. The high-pass filter uses a Laplacian-Gaussian filter, and the smoothing scale and kernel radius of the Laplacian-Gaussian filter are jointly set based on the computing resource constraints of the advertising screen terminal and the local contrast enhancement requirements to achieve a balance between detail enhancement effect and runtime overhead.

[0012] Furthermore, when driving the advertising screen terminal, the process includes: passing the panel brightness control value from the frame buffer hardware abstraction layer to the frame buffer driver; having the operating system's framework background process read the panel brightness control value from the frame buffer driver; synchronously transmitting the panel brightness control value to the light driver; and having the light driver dynamically adjust the power supply voltage of the display panel of the advertising screen terminal according to the panel brightness control value.

[0013] According to another aspect of the present invention, a high-precision advertising screen brightness display system is provided, comprising: The image brightness classification module is used to acquire the input image to be displayed, normalize the size of the input image, read the red channel value, green channel value and blue channel value of each pixel from the pixel buffer data corresponding to the input image, calculate the average brightness of the input image based on the red channel value, the green channel value and the blue channel value and determine the brightness category; The display mode determination module is used to read the device operating status information of the advertising screen terminal and determine the current display mode based on the device operating status information; The parameter combination determination module is used to call the parameter lookup table and determine the parameter combination corresponding to the input image based on the brightness category and the display mode. The parameter combination includes at least tone mapping brightness control parameters, detail enhancement parameters and panel brightness control values. The tone mapping compensation module is used to perform global tone mapping compensation processing on the input image according to the tone mapping brightness control parameters. The global tone mapping compensation processing includes linear scaling of the input brightness and global brightness mapping constrained by the maximum expressible brightness of the display panel on the linearly scaled input brightness to obtain an intermediate image. The detail enhancement module is used to perform unsharpening masking processing on the intermediate image according to the detail enhancement parameters, so as to enhance the local contrast and details of the intermediate image and obtain a compensated image; The display driver control module is used to write the compensation image into the display buffer link and send the panel brightness control value to the display driver link, so as to adjust the power supply voltage of the display panel of the advertising screen terminal while displaying the compensation image.

[0014] The technical solution of the present invention has the following beneficial effects: Compared with the prior art, the present invention can adaptively select the corresponding display adjustment parameters according to the brightness characteristics of the input image and the current operating status of the advertising screen terminal, and coordinate the control of the display content and panel drive, so as to ensure the brightness performance, local detail level and overall visual experience of the advertising image, while taking into account the display energy consumption, thermal stability and long-term operational reliability. Attached Figure Description

[0015] Figure 1 This is a flowchart illustrating a high-precision advertising screen brightness display method as described in the embodiments of this specification; Figure 2 This is a structural block diagram of a high-precision advertising screen brightness display system as described in the embodiments of this specification. Detailed Implementation

[0016] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided to make the invention more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art. The described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a full understanding of embodiments of the invention. However, those skilled in the art will recognize that the technical solutions of the invention may be practiced with one or more of these specific details omitted, or other methods, components, systems, steps, etc., may be employed. In other instances, well-known technical solutions are not shown or described in detail to avoid obscuring various aspects of the invention.

[0017] Furthermore, the accompanying drawings are merely illustrative of the invention. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted. Some block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor systems and / or microcontroller systems.

[0018] This invention provides a high-precision brightness display method for advertising screens. (See reference...) Figure 1 The diagram shown is a flowchart illustrating a high-precision advertising screen brightness display method according to an embodiment of the present invention. The method is executed in an Android all-in-one advertising screen, particularly an Android all-in-one advertising screen terminal with a battery. Specifically, the method may include the following steps S101~S106: In step S101, the input image to be displayed is obtained, the size of the input image is normalized, and the red channel value, green channel value and blue channel value of each pixel are read from the pixel buffer data corresponding to the input image. The average brightness of the input image is calculated based on the red channel value, the green channel value and the blue channel value, and the brightness category is determined.

[0019] Specifically, the pixel buffer data corresponding to the input image after display compositing is obtained, and the input image is transmitted to the frame buffer hardware abstraction layer in the form of a pixel buffer via Surfaceflinger and HWComposer. The frame buffer hardware abstraction layer reads the red channel value, green channel value and blue channel value of each pixel by accessing the pixel buffer.

[0020] The input image is normalized to a display size that matches the display resolution of the target advertising screen panel, and the average brightness is calculated based on the normalized pixel data, so that the input image corresponds to the predetermined brightness category in the parameter lookup table.

[0021] Specifically, the input image can be the final display screen after interface compositing by the display system. After entering the display chain, the view layer performs screen compositing and transmits the image to the framebuffer hardware abstraction layer via Surfaceflinger and HWComposer. In the framebuffer hardware abstraction layer, the image exists as a pixel buffer containing pixel values. By accessing this pixel buffer, the red, green, and blue channel values ​​corresponding to each pixel can be read. This setup allows the pixel data of the actual output screen to be obtained directly in the underlying display chain, avoiding inconsistencies with the final displayed content caused by estimations based solely on upper-layer application image content. This embodiment controls the framebuffer and brightness-related devices at the hardware abstraction layer, thereby achieving runtime image quality control and display adjustment.

[0022] Size normalization can be understood as adjusting the input image to a display size that matches the resolution of the target advertising screen panel, ensuring that subsequent brightness statistics, parameter lookup, and display compensation are all based on image data at a uniform resolution. This approach ensures that the average brightness calculation corresponds to the actual output state of the target advertising screen and also facilitates mapping the input image to pre-defined brightness categories in the parameter lookup table. For images with different resolutions, performing size normalization before brightness classification reduces the impact of image size differences on statistical and parameter selection results.

[0023] The red, green, and blue channel values ​​are used to calculate the average brightness of the image. This average brightness can be obtained by statistically analyzing the RGB values ​​of all pixels in the entire image. The average brightness is defined as the average of the corresponding RGB values, and this statistical result serves as the image brightness representation for subsequent parameter lookup and display control. While reducing the backlight or panel brightness control value can decrease power consumption, it can impair visual perception. Therefore, it is necessary to identify the image brightness distribution before proceeding with compensation processing to select appropriate compensation parameters for different brightness levels. For images with many dark areas and indistinct local details, the average brightness and brightness category obtained in this step provide input for subsequent brightness compensation and detail enhancement.

[0024] Brightness categories can be determined using a preset grading method, that is, mapping the input image to the corresponding category in the parameter lookup table according to the range of average brightness. In this embodiment, images with different average brightness were selected in the user subjective evaluation experiment, and evaluated in combination with different tone mapping parameters, detail enhancement parameters, and brightness values, so that different brightness images can correspond to different parameter combinations. Therefore, the brightness categories in this embodiment are not generated in isolation, but provide an index basis for subsequent parameter lookup, enabling images to enter the corresponding category according to their brightness distribution characteristics. In actual implementation, the number of brightness categories and the threshold range of each category can be set according to the panel brightness range of the target advertising screen, the content playback characteristics, and the pre-established parameter lookup table, as long as it can distinguish the input image based on average brightness and support subsequent parameter retrieval.

[0025] In step S102, the device operating status information of the advertising screen terminal is read, and the current display mode is determined based on the device operating status information.

[0026] The device operating status information includes at least one of the following: ambient light information, panel temperature information, current time period information, continuous running time information, playback task information, and preset display strategy information. After collecting the device operating status information, the advertising screen terminal is determined to be in one of the following display modes: high performance mode, balanced mode, energy-saving mode, thermal protection mode, and lifespan protection mode, based on the device operating status information. Different display modes correspond to different parameter selection strategies and different panel drive control intensities.

[0027] Specifically, in step S102, the device operating status information is used to characterize the current working conditions and control requirements of the advertising screen terminal, and serves as the basis for subsequent parameter lookup and display adjustment. The device operating status information may include at least one of the following: ambient light information, panel temperature information, current time period information, continuous running time information, playback task information, and preset display strategy information; it may also be a combination of multiple such pieces of information. After reading the device operating status information, the image is not directly compensated. Instead, the corresponding display mode is first determined based on the current operating conditions, expanding display control from a single image brightness response to a comprehensive adjustment combining the terminal status. This setting is beneficial for balancing display effect, power consumption control, and operational stability in different usage scenarios. This type of solution reads the status information in the underlying display control link and uses it to access the corresponding mode in the parameter lookup table to determine subsequent parameter combinations and brightness control values.

[0028] Display modes can include any one of the following: High Performance Mode, Balanced Mode, Energy Saving Mode, Thermal Protection Mode, and Lifespan Protection Mode. Different display modes correspond to different parameter selection strategies and different panel drive control intensities. Specifically, High Performance Mode is suitable for work states where display effect is paramount, focusing on visual satisfaction and image performance in parameter selection; Balanced Mode is suitable for normal playback states, maintaining a balance between display quality and energy consumption; Energy Saving Mode is suitable for work states with high power consumption requirements, prioritizing the control panel drive intensity while ensuring basic visibility; Thermal Protection Mode is suitable for states where panel temperature rises or continuous high load operation, suppressing heat accumulation by reducing drive intensity; Lifespan Protection Mode is suitable for long-term continuous operation or states where lifespan maintenance strategies are enabled, slowing down panel aging and improving long-term operational reliability. The relationship between operating states and display modes can be achieved through a preset mapping relationship, i.e., the current display mode is determined based on the value range of state information, priority rules, or combined judgment results.

[0029] Ambient light information reflects the external lighting conditions of the advertising screen terminal. When the ambient light is strong, external illumination weakens the subjective brightness perception and dark area visibility of the screen image. The display mode can shift towards a high-performance mode or a balanced mode to improve image compensation and maintain good visibility in subsequent parameter selection. When the ambient light is weak, the display mode can shift towards a balanced mode or an energy-saving mode to reduce unnecessary drive intensity. Panel temperature information reflects the current thermal state of the display panel. When the temperature is high, the display mode can switch to a thermal protection mode to avoid maintaining strong drive under high heat, which could lead to a decrease in thermal stability. Continuous operating time information reflects the continuous workload of the device. When the continuous operating time is long, the display mode can be adjusted to a lifespan protection mode or an energy-saving mode to mitigate the impact of long-term high-load operation on panel power supply and device lifespan.

[0030] Current time period information and playback task information reflect the actual display effect requirements of the business scenario. During peak playback periods, peak display periods, or high-priority playback task execution, the display mode can be set to high-performance mode or balanced mode to ensure the visual appeal and recognizability of the advertising content. During low-attention periods, regular playback periods, or low-priority task states, the display mode can be set to energy-saving mode or lifespan protection mode to reduce display power consumption and lower continuous operating pressure. Preset display strategy information reflects the operating rules already set on the terminal side, such as energy-saving priority strategy, image quality priority strategy, heat dissipation priority strategy, or lifespan priority strategy. When there are policy constraints, the determination of the display mode can prioritize the preset display strategy and then be adjusted in combination with other operating status information. After this processing, the mode switching can reflect both the current physical state of the terminal and the business playback goals.

[0031] In practical implementation, device operating status information can be provided by the corresponding hardware driver, system service module, or control process and passed to the parameter lookup process as input for mode determination. After the status information is read, the parameter items for the corresponding display mode can be accessed from the parameter lookup table, thus providing a basis for subsequent image compensation and panel brightness control. In existing implementations, the parameter lookup table corresponding to the power mode is accessed by reading the status information in the battery driver, and pixel conversion and display brightness scaling are performed after the parameters are determined. This indicates that the determination of the display mode is essentially an intermediate control link between the subsequent selection of parameter combinations and panel driver adjustment.

[0032] In step S103, a parameter lookup table is invoked to determine the parameter combination corresponding to the input image based on the brightness category and the display mode. The parameter combination includes at least tone mapping brightness control parameters, detail enhancement parameters, and panel brightness control values. The parameter lookup table is established as follows: training images covering different average brightness distributions are selected, and multiple sets of candidate parameter combinations are configured for each training image. Each set of candidate parameter combinations includes different tone mapping brightness control parameters, detail enhancement parameters, and panel brightness control values. Subjective visual evaluation is performed on the resulting image processed using each set of candidate parameter combinations relative to the corresponding reference image, and the display energy consumption result relative to the baseline display state is measured simultaneously. The parameter lookup table is established according to the brightness category and the display mode, so that each table entry corresponds to a target parameter combination that takes into account subjective visual satisfaction, display energy consumption effect, panel thermal stability, and long-term operating life requirements.

[0033] When the device operating status information indicates that the advertising screen terminal is in a key playback period, with strong ambient light, high viewing demand, or high playback task priority, the display mode is determined to be a high-performance mode, and the target parameter combination that meets the control requirements for display energy consumption is selected from the candidate parameter combinations with higher subjective visual scores. When the device operating status information indicates that the advertising screen terminal is in a normal playback state, the display mode is determined to be a balanced mode, and the target parameter combination that maintains a balance between human visual perception and display energy consumption is selected. When the device operating status information indicates that the advertising screen terminal is in a low-attention playback period, with high continuous operating load, increased panel temperature, or a preset energy-saving strategy is in effect, the display mode is determined to be an energy-saving mode, a thermal protection mode, or a lifespan protection mode, and the target parameter combination that meets the subjective visual satisfaction requirements is selected from the candidate parameter combinations with better display energy consumption, panel thermal stability, or long-term operating life.

[0034] Specifically, in step S103, the parameter lookup table is used to map brightness categories and display modes to specific parameter combinations, enabling the input image to obtain control parameters that match the current content features and operating state before entering subsequent compensation processing. The parameter combinations include at least tone mapping brightness control parameters, detail enhancement parameters, and panel brightness control values. The tone mapping brightness control parameters adjust image brightness and contrast, the detail enhancement parameters control local contrast and detail enhancement levels, and the panel brightness control values ​​control the driving intensity of the display panel. Based on this lookup table method, after reading the image brightness category and determining the display mode, the optimal parameter combination can be directly obtained from the parameter lookup table before pixel conversion and panel brightness scaling are performed, thus avoiding complex real-time searches or repetitive calculations during operation. The parameter lookup table acts as an intermediate bridge between image classification results and subsequent display compensation control in the underlying display control process.

[0035] The parameter lookup table can be constructed offline. During construction, training images covering different average brightness distributions are selected, and multiple sets of candidate parameter combinations are configured for each training image, allowing images with different brightness levels and content features to participate in parameter selection. Training images can be selected from image samples with different average brightness, and the tone mapping brightness control parameters, detail enhancement parameters, and panel brightness control values ​​are adjusted for each image to form multiple sets of candidate parameter combinations. In existing implementations, for global Reinhard tone mapping, the brightness control-related parameter Lwhite is adjusted to 2, 3, and 4; for detail enhancement processing, the parameter... Adjust to 4 and 7; for panel brightness control, adjust brightness values ​​to 50, 100, 150, and 200. By configuring these parameters in combination, display states under different compensation and drive intensities can be covered, providing a basic sample for establishing a parameter lookup table.

[0036] Once the candidate parameter combinations are determined, each combination can be applied to the corresponding training images, and the processing results can be visually evaluated against the reference images, while simultaneously measuring display energy consumption. The visual evaluation focuses on the subjective perception effect after local contrast and detail enhancement. During the evaluation process, a subjective score reflecting visual satisfaction is obtained by comparing the visual similarity between the processed image and the reference image. The display energy consumption result reflects the power consumption control level corresponding to different parameter combinations. By simultaneously examining both the subjective visual score and the display energy consumption result, insufficient compensation can be avoided by selecting parameters solely based on energy saving, and excessive panel drive intensity can be avoided by relying solely on visual enhancement. Specifically, when the average brightness is increased while the panel brightness control value is decreased, insufficient compensation can make dark objects difficult to distinguish, significantly reducing visual satisfaction. However, when the tone mapping and detail enhancement parameters are appropriately selected, the boundaries and details of dark objects can be more clearly distinguished, achieving a significant reduction in power consumption while maintaining a high level of human visual perception.

[0037] When establishing a parameter lookup table based on brightness category and display mode, each entry can correspond to a target parameter combination. This target parameter combination is not arbitrarily selected, but rather obtained by filtering multiple candidate parameter combinations within the same brightness category and display mode, taking into account subjective visual satisfaction, display energy consumption, panel thermal stability, and long-term operational lifespan requirements. This process allows for different parameter selection strategies for the same brightness category under different display modes. For example, in a state where display effect is prioritized, a target parameter combination that meets the control requirements for display energy consumption can be further selected from candidate parameter combinations with higher subjective visual scores; in normal playback mode, a target parameter combination that balances human visual perception and display energy consumption can be selected; and in energy-saving, thermal protection, or lifespan protection modes, a target parameter combination that meets subjective visual satisfaction requirements can be selected from candidate parameter combinations with better display energy consumption, better panel thermal stability, or better long-term operational lifespan. The parameter lookup table established in this way reflects both image brightness differences and terminal state differences, thus making subsequent adjustment results more adaptable.

[0038] When the display mode is in high-performance mode, the parameter selection strategy prioritizes visual performance, allowing for greater processing power in brightness compensation and detail restoration. During peak playback periods, in bright ambient light, when viewing demands are high, or when playback tasks are prioritized, advertising content typically requires higher recognizability and appeal. In these situations, candidate parameter combinations with higher subjective visual scores can be prioritized, and the target parameter combination can be determined while meeting energy consumption control requirements. For these scenarios, the target parameter combination in the parameter lookup table can correspond to higher tone mapping brightness control parameters, appropriately enhanced detail enhancement parameters, and corresponding panel brightness control values, ensuring that dark content, edge contours, and local details remain recognizable even under strong environmental interference.

[0039] When the display mode is set to Balanced, the parameter selection strategy aims to achieve a balance between display quality and power consumption control. Under normal playback conditions, it's unnecessary to pursue maximum brightness or strongest enhancement, nor is it advisable to simply reduce panel brightness control values ​​while ignoring visual compensation. Therefore, a target parameter combination that offers a good balance between human visual perception and display power consumption can be selected from the parameter lookup table. In this mode, the tone mapping brightness control parameters, detail enhancement parameters, and panel brightness control values ​​maintain a coordinated relationship, ensuring that the image maintains basic brightness, shadow detail, and local detail while also minimizing display power consumption. With this setting, Balanced mode is suitable for most everyday playback conditions and reduces fluctuations caused by frequent switching of extreme control strategies.

[0040] When the display mode is in energy-saving mode, thermal protection mode, or lifespan protection mode, the parameter selection strategy tends to reduce panel drive intensity and control long-term operating load. During periods of low attention playback, high continuous operating load, increased panel temperature, or when the preset energy-saving strategy is in effect, candidate parameter combinations with better display energy efficiency, better panel thermal stability, or better long-term operating life can be selected from the parameter lookup table. Then, the target parameter combination that meets the requirements of subjective visual satisfaction can be selected from among them. In this mode, the panel brightness control value is usually relatively low, and the tone mapping brightness control parameters and detail enhancement parameters are used to moderately compensate for the visual loss caused by the decrease in drive intensity, thereby maintaining basic visibility without excessively increasing the pixel compensation burden.

[0041] Therefore, this step essentially determines the parameter combination corresponding to the input image from a pre-established parameter lookup table based on the brightness category and display mode, thus establishing a synergistic relationship between the tone mapping brightness control parameters, detail enhancement parameters, and panel brightness control values. In this way, subsequent global tone mapping compensation, detail enhancement processing, and display panel drive control are all based on a unified parameter combination, enabling image quality control and panel drive control to proceed synchronously, and achieving a comprehensive balance of visual satisfaction, display energy consumption, thermal stability, and long-term operational reliability in different playback scenarios.

[0042] In step S104, global tone mapping compensation processing is performed on the input image according to the tone mapping brightness control parameters. The global tone mapping compensation processing includes linear scaling of the input brightness and global brightness mapping constrained by the maximum expressible brightness of the display panel on the linearly scaled input brightness to obtain an intermediate image.

[0043] The process of acquiring the intermediate image specifically includes: first, calculating the logarithmic average of the input brightness of the input image; then, determining a linear scaling factor based on the logarithmic average of the input brightness and the tone mapping brightness control parameter; and using the linear scaling factor to linearly scale the input brightness of each pixel to obtain an intermediate brightness; then, inputting the intermediate brightness into a brightness mapping function to obtain an output brightness within the brightness range that the advertising screen terminal can express; and compensating the pixel values ​​of the input image based on the output brightness to generate the intermediate image.

[0044] Specifically, the tone mapping compensation process employs a global Reinhard tone mapping method to perform pixel compensation on the input image. This redistributes image brightness and contrast after reducing panel drive intensity, resulting in a better visual performance of the converted image within the brightness range that the advertising screen terminal can express. This processing method applies a uniform mapping relationship to all pixels of the entire image, resulting in lower computational complexity and suitability for runtime compensation in constrained display processing environments. In this approach, the input brightness is first linearly scaled, then the output brightness is obtained through a brightness mapping function constrained by the maximum expressible brightness. The pixel values ​​of the input image are then compensated based on the output brightness to generate an intermediate image. Global tone mapping is used to compress the brightness range, avoiding oversaturation in bright areas, while preserving the basic brightness structure for subsequent detail enhancement processing.

[0045] Linear scaling of input brightness can be performed using the following formula: ; in, This represents the input brightness at pixel position (x, y). This represents the logarithmic mean brightness of the input image. This represents the linear scaling factor. By introducing the logarithmic mean brightness of the input image, brightness compensation for the entire image can be based on the overall brightness distribution of the image, rather than relying solely on the grayscale changes of a local area. This improves the consistency of compensation processing for images with different brightness distributions. A lower logarithmic mean brightness indicates that the image is generally darker, and the increase in intermediate brightness after linear scaling can be relatively more significant. Conversely, a higher logarithmic mean brightness results in a more controlled increase in intermediate brightness after linear scaling, to avoid overall overbrightness.

[0046] The linear scaling factor is set by relating the tone mapping brightness control parameter L_{white} to the logarithmic average brightness of the input image, and is determined by the following formula: ; After this processing, the tone mapping brightness control parameters This parameter can be directly used as a brightness parameter to control the intensity of image compensation. Substituting the above formula into the linear scaling relationship, it can be seen that the intermediate brightness is directly related to L_{white}. Therefore, the higher the value of L_{white}, the brighter the transformed image is usually; the lower the value of L_{white}, the smaller the brightness improvement of the transformed image. In addition to affecting the brightness improvement, the tone mapping brightness control parameter also affects the degree of brightness compression in the subsequent brightness mapping stage. Therefore, it can be used as a core parameter to control image brightness and contrast during operation.

[0047] After the linearly scaled intermediate brightness is input into the brightness mapping function, the output brightness can be determined by the following formula: ; in, Indicates pixel position The mapping relationship is used to limit the bright areas to the brightness range that the display panel can express. This compresses the input brightness exceeding a certain level at the output, thus forming a global brightness mapping constrained by the maximum expressible brightness of the display panel. With this setting, darker areas can be brightened after linear scaling, while brighter areas are suppressed through the mapping function, avoiding distortion or saturation in bright areas caused by simple linear amplification. For images with insufficient detail in dark areas after dynamic range compression, this mapping relationship provides a basis for improving dark visibility while maintaining overall brightness control.

[0048] When compensating for input image pixel values ​​based on output brightness, the original color relationships of each pixel can be preserved without being disrupted. That is, the output brightness is used as the basis for adjusting the brightness channel, and the corresponding pixel values ​​of the input image are adjusted synchronously to obtain an intermediate image. This intermediate image typically has a higher average brightness and a brightness distribution more suitable for the display panel's output range compared to the original input image. For images with dark objects, boundary contours, and local textures that are difficult to discern, the intermediate image can improve the visibility of the target area. However, global tone mapping primarily addresses brightness range compression and overall brightness distribution, with limited effect on local detail and edge enhancement. Therefore, the intermediate image is more suitable as input for subsequent detail enhancement processing.

[0049] The reason for using global Reinhard tone mapping instead of local tone mapping is that global processing applies a uniform mapping relationship to all pixels, resulting in shorter execution time and making it more suitable for execution in the display chain. While local tone mapping can enhance more local details, it usually requires higher computational overhead, which can easily lead to increased system power consumption and execution time, making it unsuitable for applications on limited terminals. Using global tone mapping as an intermediate image generation method achieves a better balance between brightness compensation capability and processing complexity, and provides stable input for subsequent image compensation processing that is coordinated with detail enhancement parameters.

[0050] In practical applications, if the panel brightness control value decreases without corresponding pixel compensation, while display power consumption can be reduced, problems such as unclear objects, insufficient detail, and decreased visual satisfaction may easily occur in dark areas of the image. After global tone mapping compensation processing controlled by tone mapping brightness control parameters, the average brightness of the intermediate image can be appropriately increased, and the visibility of target boundaries and content in dark areas is improved, thereby mitigating the visual loss caused by the decrease in panel brightness control value. Thus, the intermediate image generated in step S104 not only meets the brightness compensation requirements under controlled panel brightness conditions but also retains local contrast space for further optimization in subsequent detail enhancement processing.

[0051] In step S105, unsharpening masking is performed on the intermediate image according to the detail enhancement parameters to enhance the local contrast and details of the intermediate image, thereby obtaining a compensated image.

[0052] The acquisition of the compensated image specifically includes: performing high-pass filtering on the intermediate image to extract edge and detail information, weighting the high-pass filtering result using the detail enhancement parameters, and superimposing the weighted high-pass filtering result onto the intermediate image to obtain the compensated image; wherein, the high-pass filtering adopts a Laplacian-Gaussian filter, and the smoothing scale and kernel radius of the Laplacian-Gaussian filter are jointly set according to the computing resource constraints of the advertising screen terminal and the local contrast enhancement requirements, so as to achieve a balance between detail enhancement effect and runtime overhead.

[0053] The detail enhancement process involves performing unsharpening masking on the intermediate image to improve local contrast and edge details, thus obtaining a compensated image. Unsharpening masking is a method of enhancing image details through high-pass information. Its basic idea is to superimpose the high-pass filtering result back onto the original image, allowing the relatively smooth edge transitions in the global tone mapping compensation process to regain a clearer level of detail. This processing is suitable for further enhancing dark areas, textured areas, and target boundaries, allowing the intermediate image to continue improving local details and subjective visual perception after overall brightness redistribution. Existing techniques have shown that while global tone mapping alone can improve brightness distribution, its compensation for local detail loss remains limited. Therefore, superimposing unsharpening masking on the intermediate image helps to compensate for the insufficient detail recovery in global processing.

[0054] The compensation image can be obtained according to the following formula: ; in, This represents the enhanced and compensated image. Indicates the intermediate image. This represents the high-pass component obtained after performing high-pass filtering on the intermediate image. This represents the detail enhancement parameters. Based on the relationship, the base brightness and high-frequency detail information in the intermediate image can be superimposed, resulting in the detail enhancement parameters. Used to control the strength of high-pass component superposition. When When the value is small, the detail enhancement is relatively weak, and the compensated image is closer to the intermediate image; when... Larger values ​​result in more pronounced edge and texture details, but it's also necessary to balance processing stability and visual naturalness. With these settings, the detail enhancement parameter can be used to control local contrast and edge enhancement levels, corresponding to the parameter combinations determined in the previous steps.

[0055] The high-pass filter employs a Laplace-Gaussian filter. The Laplace-Gaussian filter is suitable for extracting edge and detail information, as it can suppress local noise interference through Gaussian smoothing and highlight areas with significant grayscale changes through the Laplace response. Therefore, it is suitable as a high-pass extraction method in unsharpened masking. The kernel size of the Laplace-Gaussian filter satisfies... ; Where M represents the filter kernel size and h represents the kernel radius. When the Laplace-Gaussian filter is used for edge detection applications, it is typically taken as... In local contrast enhancement applications, a smaller h value can be used to reduce computational load while maintaining sufficient enhancement effect. For local contrast enhancement scenarios, the kernel radius can also be reduced by making the parameter k < 1.1, which helps to reduce CPU time overhead.

[0056] The smoothing scale and kernel radius can be jointly set based on the computing resource constraints of the advertising screen terminal and the requirements for local contrast enhancement. For terminal environments with limited operating resources, the smoothing scale should not be too large, otherwise it will increase the amount of filtering computation and affect runtime processing efficiency; conversely, a smoothing scale that is too small will weaken the smoothing effect, leading to unstable detail extraction. Considering the goal of local contrast enhancement, the smoothing scale can be limited to a range suitable for enhancement processing. For example, when the smoothing scale is greater than 2, the computational overhead will increase significantly, while when the smoothing scale is less than 0.5, the smoothing effect is weak. Therefore, a suitable range can be selected. As a smoothing scale, and take The corresponding core size is Using this set of parameters achieves a better balance between detail enhancement and runtime overhead, making it more suitable for execution in the display processing chain of advertising screen terminals.

[0057] After the intermediate image undergoes Laplacian-Gaussian filtering, a high-pass component reflecting edge and local detail changes is obtained. This high-pass component is then weighted using detail enhancement parameters, and the weighted result is superimposed onto the intermediate image to form a compensated image. Compared to the intermediate image, the compensated image exhibits clearer boundary transitions, more easily discernible local details in textured areas, and greater distinction between dark objects and the background. For images with indistinct details, such as trees, shrubs, snow, indoor figures, and objects in shadow areas, unsharpened masking reveals sharper edges and more distinct layers, thus improving the lack of detail caused by global tone mapping.

[0058] From the processing results, the combination of global tone mapping and unsharpening masking can achieve local detail enhancement effects similar to or even more significant than local tone mapping while maintaining lower processing complexity. While local tone mapping can enhance local details, it often requires higher computational overhead, such as heavy frequency domain processing or more complex neighborhood operations, which is not conducive to runtime applications on limited terminals. Using the intermediate image as input for unsharpening masking allows the use of the brightness redistribution results from the previous step, followed by a relatively lightweight high-pass overlay method to restore details. This improves local contrast while considering system power consumption and execution time. Execution time comparison results show that the combined processing of global tone mapping and unsharpening masking has a significantly lower average processing time than local tone mapping, making it more suitable for continuous operation in the display pipeline.

[0059] The compensated image, as the output after detail enhancement, maintains the brightness distribution of the intermediate image after global tone mapping while improving local texture and edge performance through Qualcomm detail overlay. Therefore, it can be used as image data for subsequent writing to the display buffer link and display output. After this processing, the advertising screen terminal can still maintain good local detail, outline sharpness, and visual recognizability by reducing the panel driving intensity, thus achieving a synergistic relationship between image quality control and power consumption control.

[0060] In step S106, the compensation image is written to the display buffer link, and the panel brightness control value is sent to the display drive link to adjust the power supply voltage of the display panel of the advertising screen terminal while displaying the compensation image.

[0061] The process of driving the advertising screen terminal includes: passing the panel brightness control value from the frame buffer hardware abstraction layer to the frame buffer driver; having the operating system's framework background process read the panel brightness control value from the frame buffer driver; synchronously transmitting the panel brightness control value to the light driver; and having the light driver dynamically adjust the power supply voltage of the display panel of the advertising screen terminal according to the panel brightness control value.

[0062] The process involves generating a compensated image, writing it to the display buffer link, and sending the panel brightness control value to the display driver link. This allows image compensation processing and display panel power supply adjustment to be executed collaboratively within the same display cycle. The significance of this setup is that the compensated image corrects visual losses caused by a decrease in panel drive intensity, while the panel brightness control value dynamically adjusts the display panel power supply voltage. By working in parallel, they can maintain good image visibility and detail while reducing display power consumption. This process does not involve separate image write-back or separate brightness adjustment; instead, it combines the compensated image output with panel driver control, ensuring that pixel compensation and power supply adjustment act synchronously on the display process of the advertising screen terminal.

[0063] After the compensated image is written to the display buffer link, it can enter the display output path via the frame buffer related link, serving as the image data to be displayed. The panel brightness control value is passed from the frame buffer hardware abstraction layer to the frame buffer driver. The frame buffer driver stores the brightness control information required for current display control, which is then read and distributed by subsequent control processes. After the operating system framework background process reads the panel brightness control value from the frame buffer driver, it synchronously transmits the control value to the light driver, which then dynamically adjusts the power supply voltage to the display panel according to the current control value. Through this link, the compensation result on the image side and the brightness control value on the driver side can be transmitted along their respective paths and take effect together at the display end, thereby completing the display update and power supply voltage adjustment.

[0064] The panel brightness control value here serves as a driving intensity control factor. For AMOLED display panels, display power consumption is closely related to the panel power supply state; dynamically adjusting the display panel power supply voltage directly affects the display power consumption level. When the panel brightness control value decreases, the display panel power supply voltage decreases accordingly, reducing display power consumption; when the panel brightness control value increases, the display panel power supply voltage increases accordingly, enhancing display output capability. Since steps S104 and S105 have already compensated for image brightness distribution, local contrast, and detail, in step S106, even if the panel brightness control value is lower than the baseline display state, the advertising content can still maintain good visual performance with the help of the compensated image, thereby avoiding problems such as a darkened image, unclear objects, or loss of detail caused by simply reducing the driving intensity.

[0065] The display buffer link and the display driver link have different functions but need to work synchronously. The display buffer link focuses on carrying the data update of the compensation image, enabling the image after global tone mapping compensation and desharpening masking to enter the display output path. The display driver link focuses on carrying the transmission and execution of panel brightness control values, enabling the light driver to dynamically adjust the power supply voltage of the display panel based on the current control value. The framework background process plays a synchronizing role between the two, ensuring that the brightness control value matches the image to be displayed, avoiding asynchronous situations where the image has been switched but the driver parameters have not been updated, or the driver parameters have changed but the image compensation has not yet taken effect. Through this synchronous transmission method, the advertising screen terminal can complete the power supply voltage adjustment while displaying the compensation image, thereby maintaining consistency in display quality control and power consumption control.

[0066] In the actual driving process, the frame buffer hardware abstraction layer not only handles image buffer access and compensation image writing, but also outputs brightness control values. After the brightness control value is sent to the frame buffer driver by this layer, the background control process reads it and continues to pass it down to the light driver, which then adjusts the panel power supply based on this value. The advantage of this approach is that image compensation and panel power supply adjustment can be completed within the underlying display control chain without changing the upper-layer business content or rebuilding the entire display process. This is suitable for advertising screen terminals operating in continuous playback mode. For scenarios where advertising content is frequently refreshed or looped for extended periods, this underlying linkage method reduces control path redundancy and improves the real-time performance and stability of display control.

[0067] Thus, step S106 completes the closed-loop execution process of compensating image output and panel power supply adjustment, ensuring that the parameter combination determined in the preceding steps truly applies to the display. On one hand, the compensated image is output via the display buffer link, ensuring that the brightness levels, local contrast, and detail enhancement results of the advertising image are presented; on the other hand, the panel brightness control value is transmitted via the display drive link and executed by the light driver, ensuring that the power supply voltage of the display panel changes dynamically according to predetermined control requirements. With the cooperation of these two parts, the advertising screen terminal can adjust the panel drive intensity while displaying the compensated image, thereby achieving a comprehensive balance between display effect, display energy consumption, and continuous operational stability.

[0068] Based on the same line of thought, such as Figure 2 As shown, a high-precision advertising screen brightness display system is provided, comprising: The image brightness classification module 201 is used to acquire the input image to be displayed, perform size normalization on the input image, and read the red channel value, green channel value and blue channel value of each pixel from the pixel buffer data corresponding to the input image, calculate the average brightness of the input image based on the red channel value, the green channel value and the blue channel value and determine the brightness category; The display mode determination module 202 is used to read the device operating status information of the advertising screen terminal and determine the current display mode based on the device operating status information; The parameter combination determination module 203 is used to call the parameter lookup table and determine the parameter combination corresponding to the input image based on the brightness category and the display mode. The parameter combination includes at least tone mapping brightness control parameters, detail enhancement parameters and panel brightness control values. The tone mapping compensation module 204 is used to perform global tone mapping compensation processing on the input image according to the tone mapping brightness control parameters. The global tone mapping compensation processing includes linear scaling of the input brightness and global brightness mapping constrained by the maximum expressible brightness of the display panel on the linearly scaled input brightness to obtain an intermediate image. The detail enhancement module 205 is used to perform unsharpening masking processing on the intermediate image according to the detail enhancement parameters, so as to enhance the local contrast and details of the intermediate image and obtain a compensated image; The display driver control module 206 is used to write the compensation image into the display buffer link and send the panel brightness control value to the display driver link, so as to adjust the power supply voltage of the display panel of the advertising screen terminal while displaying the compensation image.

[0069] Compared with existing technologies, this system can adaptively select the corresponding display adjustment parameters based on the brightness characteristics of the input image and the current operating status of the advertising screen terminal, and coordinate the control of the display content and panel driver. This ensures the brightness performance, local detail level and overall visual experience of the advertising image, while also taking into account display energy consumption, thermal stability and long-term operational reliability.

[0070] It should be noted that although several modules or units of the device for performing actions have been mentioned in the detailed description above, this division is not mandatory. In fact, according to exemplary embodiments of the present invention, the features and functions of two or more modules or units described above can be embodied in one module or unit. Conversely, the features and functions of one module or unit described above can be further divided and embodied by multiple modules or units.

[0071] Other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of the invention are indicated by the claims.

[0072] It should be understood that the present invention is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A high-precision advertising screen brightness display method, characterized in that, The method includes: The input image to be displayed is obtained, the size of the input image is normalized, and the red channel value, green channel value and blue channel value of each pixel are read from the pixel buffer data corresponding to the input image. The average brightness of the input image is calculated based on the red channel value, the green channel value and the blue channel value, and the brightness category is determined. Read the device operating status information of the advertising screen terminal, and determine the current display mode based on the device operating status information; Call the parameter lookup table and determine the parameter combination corresponding to the input image based on the brightness category and the display mode. The parameter combination includes at least tone mapping brightness control parameters, detail enhancement parameters and panel brightness control values. The input image is subjected to global tone mapping compensation processing according to the tone mapping brightness control parameters. The global tone mapping compensation processing includes linear scaling of the input brightness and global brightness mapping constrained by the maximum expressible brightness of the display panel on the linearly scaled input brightness to obtain an intermediate image. The intermediate image is subjected to unsharpening masking processing based on the detail enhancement parameters to enhance the local contrast and details of the intermediate image, thereby obtaining a compensated image; The compensated image is written to the display buffer link, and the panel brightness control value is sent to the display driver link to adjust the power supply voltage of the display panel of the advertising screen terminal while displaying the compensated image.

2. The high-precision advertising screen brightness display method according to claim 1, characterized in that, The pixel buffer data corresponding to the input image after display compositing is obtained. The input image is then transmitted to the frame buffer hardware abstraction layer in the form of a pixel buffer via Surfaceflinger and HWComposer. The frame buffer hardware abstraction layer reads the red, green, and blue channel values ​​of each pixel by accessing the pixel buffer. The input image is then normalized to a display size that matches the display resolution of the target advertising screen panel, and the average brightness is calculated based on the normalized pixel data, so that the input image corresponds to the predetermined brightness category in the parameter lookup table.

3. The high-precision advertising screen brightness display method according to claim 1, characterized in that, The device operating status information includes at least one of the following: ambient light information, panel temperature information, current time period information, continuous running time information, playback task information, and preset display strategy information. After collecting the device operating status information, the advertising screen terminal is determined to be in one of the following display modes: high performance mode, balanced mode, energy-saving mode, thermal protection mode, and lifespan protection mode, based on the device operating status information. Different display modes correspond to different parameter selection strategies and different panel drive control intensities.

4. The high-precision advertising screen brightness display method according to claim 1, characterized in that, The parameter lookup table is established in the following way: Training images covering different average brightness distributions are selected, and multiple sets of candidate parameter combinations are configured for each training image. Each set of candidate parameter combinations includes different tone mapping brightness control parameters, detail enhancement parameters, and panel brightness control values. Subjective visual evaluation is performed on the resulting image after processing with the candidate parameter combinations described in each group, relative to the corresponding reference image, and the display energy consumption result relative to the baseline display state is measured simultaneously. The parameter lookup table is established according to the brightness category and the display mode, so that each entry corresponds to a target parameter combination that takes into account subjective visual satisfaction, display energy consumption, panel thermal stability and long-term operating life requirements.

5. The high-precision advertising screen brightness display method according to claim 4, characterized in that, When the device operation status information indicates that the advertising screen terminal is in a key playback period, the ambient light is strong, the viewing demand is high, or the playback task has a high priority, the display mode is determined to be a high performance mode, and the target parameter combination that meets the control requirements is selected from the candidate parameter combinations with higher subjective visual scores. When the device operating status information indicates that the advertising screen terminal is in normal playback state, the display mode is determined to be balanced mode, and the target parameter combination that maintains a balance between human eye perception effect and display energy consumption effect is selected. When the device operation status information indicates that the advertising screen terminal is in a low attention playback period, has a high continuous operating load, has an increased panel temperature, or has a preset energy-saving strategy in effect, the display mode is determined to be energy-saving mode, thermal protection mode, or life protection mode, and the target parameter combination that meets the subjective visual satisfaction requirements is selected from the candidate parameter combinations that are superior in display energy consumption effect, panel thermal stability, or long-term operating life.

6. The high-precision advertising screen brightness display method according to claim 1, characterized in that, The acquisition of the intermediate image specifically includes: First, the logarithmic average of the input brightness of the input image is calculated. Then, a linear scaling factor is determined based on the logarithmic average of the input brightness and the tone mapping brightness control parameter. The input brightness of each pixel is linearly scaled using the linear scaling factor to obtain an intermediate brightness. Then, the intermediate brightness is input to the brightness mapping function to obtain the output brightness within the brightness range that the advertising screen terminal can express. The pixel values ​​of the input image are compensated based on the output brightness to generate the intermediate image.

7. The high-precision advertising screen brightness display method according to claim 1, characterized in that, The acquisition of the compensated image specifically includes: A high-pass filter is applied to the intermediate image to extract edge and detail information. The high-pass filter result is weighted using the detail enhancement parameters, and the weighted high-pass filter result is superimposed on the intermediate image to obtain the compensated image. The high-pass filter uses a Laplacian-Gaussian filter, and the smoothing scale and kernel radius of the Laplacian-Gaussian filter are jointly set based on the computing resource constraints of the advertising screen terminal and the local contrast enhancement requirements to achieve a balance between detail enhancement effect and runtime overhead.

8. The high-precision advertising screen brightness display method according to claim 1, characterized in that, When driving the advertising screen terminal, the process includes: passing the panel brightness control value from the frame buffer hardware abstraction layer to the frame buffer driver; having the operating system's framework background process read the panel brightness control value from the frame buffer driver; synchronously transmitting the panel brightness control value to the light driver; and having the light driver dynamically adjust the power supply voltage of the display panel of the advertising screen terminal according to the panel brightness control value.

9. A high-precision advertising screen brightness display system, characterized in that, include: The image brightness classification module is used to acquire the input image to be displayed, normalize the size of the input image, read the red channel value, green channel value and blue channel value of each pixel from the pixel buffer data corresponding to the input image, calculate the average brightness of the input image based on the red channel value, the green channel value and the blue channel value and determine the brightness category; The display mode determination module is used to read the device operating status information of the advertising screen terminal and determine the current display mode based on the device operating status information; The parameter combination determination module is used to call the parameter lookup table and determine the parameter combination corresponding to the input image based on the brightness category and the display mode. The parameter combination includes at least tone mapping brightness control parameters, detail enhancement parameters and panel brightness control values. The tone mapping compensation module is used to perform global tone mapping compensation processing on the input image according to the tone mapping brightness control parameters. The global tone mapping compensation processing includes linear scaling of the input brightness and global brightness mapping constrained by the maximum expressible brightness of the display panel on the linearly scaled input brightness to obtain an intermediate image. The detail enhancement module is used to perform unsharpening masking processing on the intermediate image according to the detail enhancement parameters, so as to enhance the local contrast and details of the intermediate image and obtain a compensated image; The display driver control module is used to write the compensation image into the display buffer link and send the panel brightness control value to the display driver link, so as to adjust the power supply voltage of the display panel of the advertising screen terminal while displaying the compensation image.

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