HDR and SDR brightness curve adaptive switching method and system based on environmental perception

Abstract

The invention discloses an HDR and SDR brightness curve adaptive switching method and system based on environmental perception. The method comprises the following steps: S10, presetting HDR brightness values hpre1 and hpre2, and presetting SDR brightness values spre1 and spre2; s11, acquiring environment light intensity data in real time, and determining a current environment illumination parameter according to historical data; s12, when the video stream in the HDR format is played or the playing of the video stream in the HDR format is ended, storing the format type of the current picture content; s13, dynamically switching and generating an SDR or HDR content brightness mapping curve according to the environment illumination parameter and the picture content format type; and S14, applying the selected curve to a backlight control program, and driving a backlight chip to complete brightness display of each partition. The problem that the brightness is not matched when the Mini-LED display device displays HDR and SDR contents in different environments is solved, the visual experience of the multi-partition Mini-LED display device is improved, and the power consumption is optimized.

Description

Technical Field

[0001] The present invention relates to the field of image display technology, and in particular to a method and system for adaptively switching between HDR and SDR brightness curves based on environment perception. Background Art

[0002] With the development of display technology, multi-zone dynamic light control Mini-LED display devices are becoming increasingly popular in the market. In existing technologies, due to the different brightness requirements and standards for HDR and SDR content (HDR peak brightness reaches over 1000 nits, while SDR is generally 100-300 nits), multi-zone Mini-LED display devices still face the following problems when displaying HDR and SDR content in different environments:

[0003] 1. Some Mini-LED display devices rely on users to manually switch display modes to adjust the brightness curve. This method is not only cumbersome to operate but also cannot adapt to dynamic environmental changes. It may cause problems such as HDR brightness overexposure in dark environments and low contrast of SDR content in bright environments.

[0004] 2. Some Mini-LED display devices use a fixed brightness curve, which results in poor applicability to content scenarios. Problems may arise, such as insufficient brightness and poor image quality for HDR content, and excessive brightness and low energy efficiency for SDR content.

[0005] 3. The existing ambient light sensor is only used to adjust the backlight intensity and is not coordinated with the brightness mapping curve of HDR / SDR content. Summary of the Invention

[0006] The main purpose of this disclosure is to provide a method and system for adaptively switching HDR and SDR brightness curves based on environmental perception, which solves the brightness mismatch problem when the above-mentioned Mini-LED display device displays HDR and SDR content in different environments, thereby improving the visual experience of multi-zone Mini-LED display devices and optimizing power consumption;

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] A method for adaptively switching between HDR and SDR brightness curves based on environment perception, comprising the following steps:

[0009] S10: Preset HDR brightness values ​​h_pre1 and h_pre2, and preset SDR brightness values ​​s_pre1 and s_pre2;

[0010] S11: Acquire ambient light intensity data in real time and determine current ambient illumination parameters based on historical data;

[0011] S12: When playing or ending the HDR format video stream, save the current picture content format type;

[0012] S13: Dynamically switch and generate SDR or HDR content brightness mapping curves based on ambient illumination parameters and the image content format type;

[0013] S14: applying the selected curve to the backlight control program and driving the backlight chip to complete the brightness display of each partition;

[0014] Specifically, in step S10, the brightness value h_pre1 is the HDR peak brightness value, which is in a linear functional relationship with the HDR backlight peak current, the brightness value h_pre2 is the HDR white field brightness value, which is in a linear functional relationship with the HDR backlight white field current, the brightness value s_pre1 is the SDR peak brightness value, which is in a linear functional relationship with the SDR backlight peak current, and the brightness value s_pre2 is the SDR white field brightness value, which is in a linear functional relationship with the SDR backlight white field current;

[0015] Specifically, in step S11, the method of acquiring ambient light intensity data in real time and determining the current ambient illumination parameter based on historical data includes:

[0016] S11-11: Use a sliding window mean filter to suppress data noise and obtain denoised ambient light intensity data;

[0017] S11-12: Update the ambient illumination parameters based on historical data and the preset hysteresis interval;

[0018] Specifically, in step S11-11, the sliding window mean filter ambient light denoising formula is as follows:

[0019] lux avg =sum(lux_buffer[0:N-1]) / N

[0020] The window width N needs to be determined according to the actual accuracy of the ambient light sensor.

[0021] Specifically, in step S11-12, in order to prevent the ambient illumination parameter from switching frequently, the ambient illumination parameter is updated based on the comparison between the historical data and the preset hysteresis interval. The pseudo code of the method is as follows:

[0022] if(abs(lux_current–lux_previous)>threshold){

[0023] update_lux(lux_current);

[0024] }

[0025] Threshold is a hysteresis interval parameter, and its setting value is generally between [50,200]. It can prevent the ambient illumination parameter from frequently switching, and can also prevent the ambient illumination parameter from changing too little after the ambient illumination changes significantly.

[0026] Furthermore, in step S12, the method for saving the picture content format type when playing or ending the playback of the HDR format video stream includes applying for a global memory space to store the picture content format type data; when the HDR format video is played and the underlying video codec driver starts the HDR format video decoding task, setting the picture content format type storage data to "HDR"; when the HDR format video is played and the underlying video codec driver ends the HDR format video decoding task, setting the picture content format type storage data to "SDR".

[0027] Specifically, in step S13, the method for dynamically switching the SDR or HDR content brightness mapping curve includes:

[0028] S13-11: Make brightness curve switching decision;

[0029] S13-12: Using the brightness curve mutation protection algorithm, determine the current peak brightness value P_current;

[0030] Specifically, in S13-11, the brightness curve switching decision method includes:

[0031] S13-11-1: Determine the current screen content format type;

[0032] S13-11-2: When it is determined that the picture content format type has changed, and the current picture content format type is determined to be HDR, start to enable the HDR brightness curve;

[0033] S13-11-3: When it is determined that the image content format type has changed and the current image content format type is SDR, the SDR brightness curve is enabled;

[0034] Specifically, in S13-12, the present invention proposes a brightness curve mutation protection algorithm based on smooth and gradual change of time domain peak value to avoid visual discomfort caused by sudden brightness changes of the curve. The algorithm includes the following specific formula:

[0035] P_current=P1+(P2-P1)*p_time

[0036] Where P1 and P2 are peak brightness values, P_current is the peak brightness value obtained after calculation, and p_time is the time change factor parameter, with a value range of [0,1].

[0037] Further, in S13-12, when it is determined to start enabling the HDR brightness curve, the peak brightness value P1 is set to s_pre1, the peak brightness value P2 is set to h_pre1, and the current peak brightness value P_current is determined according to the time variation factor;

[0038] Further, in S13-12, when it is determined to start using the SDR brightness curve, the peak brightness value P1 is set to h_pre1, the peak brightness value P2 is set to s_pre1, and the current peak brightness value P_current is determined according to the time variation factor;

[0039] Furthermore, in step S13, the method for dynamically generating an SDR or HDR content brightness mapping curve includes:

[0040] S13-21: Determine the peak brightness value P and the white field brightness values ​​W1 and W2;

[0041] S13-22: Obtain the current ambient illumination parameter and the current image signal window size APL;

[0042] S13-23: Generate SDR or HDR content brightness mapping curve in real time based on a preset algorithm;

[0043] Specifically, in step S13-21, the peak brightness value P is the current peak brightness value P_current, the white field brightness value W1 is h_pre2, and the white field brightness value W2 is s_pre2;

[0044] Specifically, in step S13-23, the preset algorithm formula for generating the brightness mapping curve is:

[0045]

[0046] Among them, α is the white field brightness parameter, β is the peak brightness parameter, and lcom is the ambient light compensation parameter;

[0047] Furthermore, when generating the HDR content brightness mapping curve, in step S13-23, in the preset algorithm formula, the white field brightness parameter uses the brightness value W1, and the peak brightness parameter uses the peak brightness value P;

[0048] Furthermore, when generating the SDR content brightness mapping curve, in step S13-23, in the preset algorithm formula, the white field brightness parameter uses the brightness value W2, and the peak brightness parameter uses the peak brightness value P;

[0049] Furthermore, when generating the SDR or HDR content brightness mapping curve, in the preset algorithm formula, the ambient light compensation parameter is calculated by the current ambient illumination parameter, and the algorithm relationship is:

[0050]

[0051] Where ω is the ambient illumination parameter value.

[0052] According to a second aspect of an embodiment of the present disclosure, a system for adaptively switching between HDR and SDR brightness curves based on environment perception is provided, which is applied to a Mini-LED display device, including:

[0053] Parameter configuration module, used to save the preset HDR peak brightness value h_pre1, HDR white field brightness value h_pre2, SDR peak brightness value s_pre1 and SDR white field brightness value s_pre2;

[0054] Environmental perception module, used to obtain ambient light intensity data in real time and determine the current ambient illumination parameters based on historical data;

[0055] The content analysis module is used to save the current picture content format type and update the picture content format type data when playing or ending the HDR format video stream;

[0056] Adaptive algorithm module, used to dynamically switch and generate SDR or HDR content brightness mapping curves based on ambient illumination parameters and the image content format type;

[0057] The backlight control module is used to apply the selected brightness curve and drive the backlight chip to complete the brightness display of each partition. The beneficial effects that may be brought about by the method disclosed in this application include but are not limited to:

[0058] The present disclosure provides a method and system for adaptively switching HDR and SDR brightness curves based on environmental perception, which solves the brightness mismatch problem when Mini-LED display devices display HDR and SDR content in different environments, and can enhance the visual experience of multi-partition Mini-LED display devices and optimize power consumption.

[0059] In the technical solution provided by the present invention, through the dynamic switching method of SDR and HDR content brightness mapping curves, the Mini-LED display device can adaptively switch to the brightness mapping curve that conforms to the content format brightness under different format contents, thereby solving the problems of poor applicability of content scenarios caused by the use of fixed brightness curves by Mini-LED display devices, such as insufficient brightness and poor picture quality of HDR content, and excessive brightness and low energy efficiency of SDR content; at the same time, through the brightness curve mutation protection algorithm of the present invention, the brightness curve can be smoothly switched within a preset time frame, avoiding visual discomfort caused by sudden brightness changes of the curve, avoiding visual abruptness, and realizing user-free switching.

[0060] At the same time, through the dynamic generation method of SDR and HDR content brightness mapping curves of the present invention, in a dark light environment, the brightness of the HDR content can be appropriately reduced to prevent HDR brightness overexposure, thereby reducing the power consumption of the entire machine while ensuring image quality; in strong light conditions, the brightness of the SDR content can be increased to compensate for ambient light, alleviate the problem of low visibility of the SDR content, and enhance the user's visual experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 1 is a flow chart illustrating a method for adaptively switching between HDR and SDR brightness curves based on environment perception according to an exemplary embodiment of the present disclosure;

[0062] Figure 2 1 is a flow chart illustrating a method for adaptively switching between HDR and SDR brightness curves based on environment perception according to an exemplary embodiment of the present disclosure;

[0063] Figure 3 1 is a flow chart illustrating a method for adaptively switching between HDR and SDR brightness curves based on environment perception according to an exemplary embodiment of the present disclosure;

[0064] Figure 4 3 is a block diagram of an adaptive switching system for HDR and SDR brightness curves based on environment perception according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0065] In order to make the purpose, technical solutions and advantages of this application more clearly understood, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0066] On the contrary, this application covers any alternatives, modifications, equivalents, and solutions made within the spirit and scope of this application as defined by the claims. Furthermore, to facilitate a better understanding of this application, certain specific details are described in detail below in the detailed description of this application. Those skilled in the art will be able to fully understand this application without these details.

[0067] The following is a detailed description of an adaptive switching method between HDR and SDR brightness curves based on environmental perception involved in an embodiment of the present application.

[0068] Figure 1 : is a flow chart of an exemplary embodiment of the present disclosure showing a method for adaptively switching between HDR and SDR brightness curves based on environment perception. Figure 1 As shown, the method is applied to a Mini-LED display device and includes the following steps:

[0069] S10: Preset HDR brightness values ​​h_pre1 and h_pre2, and preset SDR brightness values ​​s_pre1 and s_pre2;

[0070] S11: Acquire ambient light intensity data in real time and determine current ambient illumination parameters based on historical data;

[0071] S12: When playing or ending the HDR format video stream, save the current picture content format type;

[0072] S13: Dynamically switch and generate SDR or HDR content brightness mapping curves based on ambient illumination parameters and the image content format type;

[0073] S14: applying the selected curve to the backlight control program and driving the backlight chip to complete the brightness display of each partition;

[0074] Specifically, in step S10, the brightness value h_pre1 is the HDR peak brightness value, which is in a linear functional relationship with the HDR backlight peak current, the brightness value h_pre2 is the HDR white field brightness value, which is in a linear functional relationship with the HDR backlight white field current, the brightness value s_pre1 is the SDR peak brightness value, which is in a linear functional relationship with the SDR backlight peak current, and the brightness value s_pre2 is the SDR white field brightness value, which is in a linear functional relationship with the SDR backlight white field current;

[0075] Figure 2 : is a flow chart of an exemplary embodiment of the present disclosure showing a method for adaptively switching between HDR and SDR brightness curves based on environment perception. Figure 2 Specifically, in step S11, the method for acquiring ambient light intensity data in real time and determining the current ambient illumination parameter according to historical data includes the following steps:

[0076] S11-11: Use a sliding window mean filter to suppress data noise and obtain denoised ambient light intensity data;

[0077] S11-12: Update the ambient illumination parameters based on historical data and the preset hysteresis interval;

[0078] Specifically, in step S11-11, the sliding window mean filter ambient light denoising formula is as follows:

[0079] lux avg =sum(lux_buffer[0:N-1]) / N

[0080] The window width N needs to be determined according to the actual accuracy of the ambient light sensor.

[0081] Specifically, in step S11-12, in order to prevent the ambient illumination parameter from switching frequently, the ambient illumination parameter is updated based on the comparison between the historical data and the preset hysteresis interval. The pseudo code of the method is as follows:

[0082] if(abs(lux_current–lux_previous)>threshold){

[0083] update_lux(lux_current);

[0084] }

[0085] Threshold is a hysteresis interval parameter, and its setting value is generally between [50, 200]. It can prevent the ambient illumination parameter from frequently changing, and can also prevent the ambient illumination parameter from changing too little after the ambient illumination changes significantly.

[0086] Furthermore, in step S12, the method for saving the picture content format type when playing or ending the playback of the HDR format video stream includes applying for a global memory space to store the picture content format type data; when the HDR format video is played and the underlying video codec driver starts the HDR format video decoding task, setting the picture content format type storage data to "HDR"; when the HDR format video is played and the underlying video codec driver ends the HDR format video decoding task, setting the picture content format type storage data to "SDR".

[0087] Figure 3 : is a flow chart of an exemplary embodiment of the present disclosure showing a method for adaptively switching between HDR and SDR brightness curves based on environment perception. Figure 3 Specifically, in step S13, the method for dynamically switching the SDR or HDR content brightness mapping curve includes:

[0088] S13-11: Make brightness curve switching decision;

[0089] S13-12: Using the brightness curve mutation protection algorithm, determine the current peak brightness value P_current;

[0090] Specifically, in S13-11, the brightness curve switching decision method includes:

[0091] S13-11-1: Determine the current screen content format type;

[0092] S13-11-2: When it is determined that the picture content format type has changed, and the current picture content format type is determined to be HDR, start to enable the HDR brightness curve;

[0093] S13-11-3: When it is determined that the image content format type has changed and the current image content format type is SDR, the SDR brightness curve is enabled;

[0094] Specifically, in S13-12, the present invention proposes a brightness curve mutation protection algorithm based on smooth and gradual change of time domain peak value to avoid visual discomfort caused by sudden brightness changes of the curve. The algorithm includes the following specific formula:

[0095] P_current=P1+(P2-P1)*p_time

[0096] Where P1 and P2 are peak brightness values, P_current is the peak brightness value obtained after calculation, and p_time is the time change factor parameter, with a value range of [0,1].

[0097] Further, in S13-12, when it is determined to start enabling the HDR brightness curve, the peak brightness value P1 is set to s_pre1, the peak brightness value P2 is set to h_pre1, and the current peak brightness value P_current is determined according to the time variation factor;

[0098] Further, in S13-12, when it is determined to start using the SDR brightness curve, the peak brightness value P1 is set to h_pre1, the peak brightness value P2 is set to s_pre1, and the current peak brightness value P_current is determined according to the time variation factor;

[0099] It can be understood that, through the brightness curve switching decision method described in the embodiment of the present invention, the Mini-LED display device can adaptively switch to a brightness mapping curve that conforms to the brightness of the content format under different formats (HDR, SDR), which solves the problem that the Mini-LED display device uses a fixed brightness curve, resulting in poor applicability of content scenarios, such as insufficient brightness and poor picture quality of HDR content, and excessive brightness and low energy efficiency of SDR content. At the same time, through the brightness curve mutation protection algorithm of the present invention, the brightness curve can be smoothly switched within a preset time frame, avoiding visual discomfort caused by sudden brightness changes of the curve, avoiding visual abruptness, and realizing user-free switching.

[0100] Furthermore, in step S13, the method for dynamically generating an SDR or HDR content brightness mapping curve includes:

[0101] S13-21: Determine the peak brightness value P and the white field brightness values ​​W1 and W2;

[0102] S13-22: Obtain the current ambient illumination parameter and the current image signal window size APL;

[0103] S13-23: Generate SDR or HDR content brightness mapping curve in real time based on a preset algorithm;

[0104] Specifically, in step S13-21, the peak brightness value P is the current peak brightness value P_current, the white field brightness value W1 is h_pre2, and the white field brightness value W2 is s_pre2;

[0105] Specifically, in step S13-23, the preset algorithm formula for generating the brightness mapping curve is:

[0106]

[0107] Among them, α is the white field brightness parameter, β is the peak brightness parameter, and lcom is the ambient light compensation parameter;

[0108] Furthermore, when generating the HDR content brightness mapping curve, in step S13-23, in the preset algorithm formula, the white field brightness parameter uses the brightness value W1, and the peak brightness parameter uses the peak brightness value P;

[0109] Furthermore, when generating the SDR content brightness mapping curve, in step S13-23, in the preset algorithm formula, the white field brightness parameter uses the brightness value W2, and the peak brightness parameter uses the peak brightness value P;

[0110] Furthermore, when generating the SDR or HDR content brightness mapping curve, in the preset algorithm formula, the ambient light compensation parameter is calculated by the current ambient illumination parameter, and the algorithm relationship is:

[0111]

[0112] Where ω is the ambient illumination parameter value.

[0113] It can be understood that, through the different ambient light compensation weight algorithms for HDR and SDR in the embodiments of the present invention, in a dark light environment (e.g., the ambient light is less than 2000 lux), the brightness of the HDR content can be appropriately reduced to prevent HDR brightness overexposure, thereby reducing the power consumption of the entire device while ensuring image quality; in a strong light condition (e.g., the ambient light is greater than 5000 lux), the brightness compensation of the SDR content can be increased to alleviate the problem of low visibility of the SDR content and improve the user's visual experience;

[0114] Figure 4 is a block diagram of an adaptive switching system of HDR and SDR brightness curves based on environment perception shown in an exemplary embodiment of the present disclosure. Figure 4As shown, an HDR and SDR brightness curve adaptive switching system based on environmental perception is applied to Mini-LED display devices, including a parameter configuration module, an environmental perception module, an adaptive algorithm module, and a backlight control module.

[0115] Parameter configuration module, used to save the preset HDR peak brightness value h_pre1, HDR white field brightness value h_pre2, SDR peak brightness value s_pre1 and SDR white field brightness value s_pre2;

[0116] Environmental perception module, used to obtain ambient light intensity data in real time and determine the current ambient illumination parameters based on historical data;

[0117] The content analysis module is used to save the current picture content format type and update the picture content format type data when playing or ending the HDR format video stream;

[0118] Adaptive algorithm module, used to dynamically switch and generate SDR or HDR content brightness mapping curves based on ambient illumination parameters and the image content format type;

[0119] The backlight control module is used to apply the selected brightness curve and drive the backlight chip to complete the brightness display of each partition.

[0120] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for adaptively switching between HDR and SDR brightness curves based on environmental perception, characterized in that: The following steps are involved: S10: Preset HDR brightness values ​​h_pre1 and h_pre2, and preset SDR brightness values ​​s_pre1 and s_pre2; S11: Acquire ambient light intensity data in real time and determine current ambient illumination parameters based on historical data; S12: When playing or ending the HDR format video stream, save the current picture content format type; S13: Dynamically switch and generate SDR or HDR content brightness mapping curves based on ambient illumination parameters and the image content format type; S14: Apply the selected curve to the backlight control program and drive the backlight chip to complete the brightness display of each partition.

2. The method according to claim 1, characterized in that The method for acquiring ambient light intensity data in real time and determining the current ambient illumination parameter based on historical data includes: S11-11: Use a sliding window mean filter to suppress data noise and obtain denoised ambient light intensity data; S11-12: Update the ambient illumination parameters based on the historical data and the preset hysteresis interval.

3. The method according to claim 2, characterized in that The sliding window mean filter ambient light denoising formula is as follows: lux avg =sum(lux_buffer[0:N-1]) / N The window width N needs to be determined according to the actual accuracy of the ambient light sensor.

4. The method according to claim 1, characterized in that The method for saving the picture content format type when playing or ending the HDR format video stream includes: Apply for global memory space to store the picture content format type data. When the HDR format video is playing and the underlying video codec driver starts the HDR format video decoding task, set the picture content format type storage data to "HDR". When the HDR format video playback ends and the underlying video codec driver ends the HDR format video decoding task, set the picture content format type storage data to "SDR".

5. The method according to claim 1, characterized in that: The method for dynamically switching the SDR or HDR content brightness mapping curve includes: S13-11: Make brightness curve switching decision; S13-12: Using the brightness curve mutation protection algorithm, determine the current peak brightness value P_current; The brightness curve switching decision includes: S13-11-1: Determine the current screen content format type; S13-11-2: When it is determined that the picture content format type has changed, and the current picture content format type is determined to be HDR, start to enable the HDR brightness curve; S13-11-3: When it is determined that the picture content format type has changed, and it is determined that the current picture content format type is SDR, start to enable the SDR brightness curve.

6. The method according to claim 5, characterized in that The specific formula of S13-12: using the brightness curve mutation protection algorithm is as follows: P_current=P1+(P2-P1)*p_time Where P1 and P2 are peak brightness values, P_current is the peak brightness value obtained after calculation, and p_time is the time change factor parameter, with a value range of [0,1].

7. The method according to claim 1, characterized in that: The method for dynamically generating an SDR or HDR content brightness mapping curve includes: S13-21: Determine the peak brightness value P and the white field brightness values ​​W1 and W2; S13-22: Obtain the current ambient illumination parameter and the current image signal window size APL; S13-23: Generate the SDR or HDR content brightness mapping curve in real time based on a preset algorithm.

8. The method according to claim 7, characterized in that: The preset algorithm formula for generating the brightness mapping curve is: Among them, α is the white field brightness parameter, β is the peak brightness parameter, and lcom is the ambient light compensation parameter.

9. The method according to claim 8, characterized in that When generating an SDR or HDR content brightness mapping curve, in the preset algorithm formula, the ambient light compensation parameter is calculated from the current ambient illumination parameter, and the algorithm relationship is: Where ω is the ambient illumination parameter value.

10. A system for adaptively switching between HDR and SDR brightness curves based on environment perception, applied to the method according to any one of claims 1 to 9, comprising: Parameter configuration module, used to save the preset HDR peak brightness value h_pre1, HDR white field brightness value h_pre2, SDR peak brightness value s_pre1 and SDR white field brightness value s_pre2; Environmental perception module, used to obtain ambient light intensity data in real time and determine the current ambient illumination parameters based on historical data; The content analysis module is used to save the current picture content format type and update the picture content format type data when playing or ending the HDR format video stream; Adaptive algorithm module, used to dynamically switch and generate SDR or HDR content brightness mapping curves based on ambient illumination parameters and the image content format type; The backlight control module is used to apply the selected brightness curve and drive the backlight chip to complete the brightness display of each partition.

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