WO2018161592A1

WO2018161592A1 - Method, device, storage medium, and electronic apparatus for changing background grayscale level to save power

Info

Publication number: WO2018161592A1
Application number: PCT/CN2017/107185
Authority: WO
Inventors: 郑志勇; 易永鹏; 苟生俊; 袁晓日; 甘高亭; 杨海; 彭德良
Original assignee: 广东欧珀移动通信有限公司
Priority date: 2017-03-10
Filing date: 2017-10-21
Publication date: 2018-09-13
Also published as: CN106817753A; CN106817753B

Abstract

Disclosed in embodiments of the present application are a method, device, storage medium, and electronic apparatus for changing a background grayscale level to save power. The method comprises: if a backlight control function is in an on state, then detecting a remaining power level of a terminal; if the remaining power level is detected to be less than or equal to a power level threshold, lowering a grayscale level of a background image on a screen, and refreshing a display frame on the screen; and adjusting, on the basis of the backlight control function, a grayscale level and screen backlight brightness for the refreshed display frame on the screen.

Description

Method, device, storage medium and electronic device for switching background gray scale for power saving

This application claims priority from the Chinese Patent Application submitted to the China Patent Office on March 25, 2017, the application number is 201710142351.X, and the invention name is “a method, device and mobile terminal for switching background gray scale for power saving”. The entire content of which is incorporated herein by reference.

Technical field

The present application relates to the field of electronic devices, and in particular, to a method, an apparatus, a storage medium, and an electronic device for switching background gray scales for power saving.

Background technique

With the rapid development of mobile communication technology and computer technology, mobile terminals such as smart phones and tablets have become indispensable communication tools in people's lives. How to balance the low power consumption requirements of the terminal and the image quality of the screen display is an urgent problem in the image processing field.

Backlight control functions such as content adaptation to backlight control (Content Adaptive Brightness The Control, CABC function is used to adjust the relationship between the grayscale value of the image and the brightness of the screen backlight according to the image content displayed on the terminal screen, and can effectively reduce the brightness of the screen backlight while maintaining the image display quality. However, due to the limitation of the image content displayed on the screen, the power saving effect based on the backlight control function is currently poor, resulting in the problem that the terminal still has a short battery life.

technical problem

The embodiment of the present invention provides a method, a device, a storage medium, and an electronic device for switching background gray scales for power saving, which can extend the terminal life of the terminal.

Technical solution

In a first aspect, an embodiment of the present application provides a method for switching a background grayscale to save power, including:

If the backlight control function is in the on state, detecting the remaining power value of the terminal;

When detecting that the remaining power value is lower than or equal to the power threshold, lowering the gray level of the screen background image to update the screen display screen;

The grayscale and screen backlight brightness are adjusted on the updated screen display screen based on the backlight control function.

In a second aspect, the embodiment of the present application provides a device for switching a background gray scale to save power, including:

The power detecting module is configured to detect a remaining power value of the terminal if the backlight control function is in an open state;

a screen grayscale reduction module, configured to reduce a grayscale of the screen background image to update the screen display screen when detecting that the remaining power value is lower than or equal to the power threshold;

The backlight adjustment module is configured to adjust the grayscale and screen backlight brightness of the updated screen display screen based on the backlight control function.

In a third aspect, an embodiment of the present disclosure provides a storage medium, where the storage medium stores a plurality of instructions, where the instructions are adapted to be loaded by a processor to perform a switching background grayscale provided by any one of the embodiments of the present invention. Electrical method.

In a fourth aspect, an embodiment of the present application provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor implements the following when the computer program is executed step:

If the backlight control function is in an on state, detecting a remaining power value of the electronic device;

Beneficial effect

DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings used in the description of the embodiments will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the present application. Other drawings can also be obtained from those skilled in the art based on these drawings without paying any creative effort.

FIG. 1 is a schematic flowchart of a method for switching a background gray scale to save power according to an embodiment of the present application;

2 is a schematic diagram of a current display image provided in an embodiment of the present application;

FIG. 3 is a schematic flowchart of still another method for switching a background gray scale to save power according to an embodiment of the present application;

4 is a schematic structural diagram of an apparatus for switching a background gray scale to save power according to an embodiment of the present application;

FIG. 5 is a schematic structural diagram of a mobile terminal provided in an embodiment of the present application.

BEST MODE FOR CARRYING OUT THE INVENTION

The present application will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the application and are not intended to be limiting. In addition, it should be noted that, for the convenience of description, only some but not all of the structures related to the present application are shown in the drawings.

Before discussing the exemplary embodiments in more detail, it should be noted that some exemplary embodiments are described as a process or method depicted as a flowchart. Although the flowcharts describe the various steps as a sequential process, many of the steps can be implemented in parallel, concurrently, or concurrently. In addition, the order of the steps can be rearranged. The process may be terminated when its operation is completed, but may also have additional steps not included in the figures. The processing may correspond to methods, functions, procedures, subroutines, subroutines, and the like.

An embodiment of the present application provides a method for switching a background gray scale to save power, including:

In an embodiment, reducing the grayscale of the background image of the screen includes:

Selecting and updating a target background image of the screen from the preset at least one power saving background image, wherein the grayscale of the power saving background image is less than a grayscale threshold.

In an embodiment, selecting and updating a target background image of the screen from the preset at least one power saving background image includes:

If the screen is in a static picture type scene, the first power saving background image is determined as the target background image of the screen;

If the screen is in the picture preview scene, the second power saving background image is determined as the target background image of the screen;

If the screen is in a dynamic scene, the third power saving background image is determined as the target background image of the screen;

The gray level of the first power saving background image, the second power saving background image, and the third power saving background image are sequentially decreased.

In an embodiment, after selecting and updating the target background image of the screen from the preset at least one power saving background image, the method includes:

Upon detecting a charging event and the remaining charge value of the screen is above the power threshold, the initial background image is re-used as the target background image for the screen.

The gray scale of each pixel in the initial background image is subtracted from the preset value.

In an embodiment, the grayscale boosting amplitude of the updated screen display screen is the same as the screen backlight brightness reduction amplitude based on the backlight control function.

In an embodiment, selecting and updating a target background image of the screen from the preset at least one power saving background image further includes:

The type of scene in which the screen is located is determined according to at least one of the display frame characteristics, the user behavior characteristics, or the camera status of the screen.

FIG. 1 is a schematic flowchart of a method for switching a background gray scale to save power according to an embodiment of the present disclosure. The method may be performed by a device that switches background gray scales to save power, and the device may be implemented by software and/or hardware. Generally, it can be loaded in an electronic device such as a mobile terminal. As shown in FIG. 1, the method can include:

Step 11. If the backlight control function is in the on state, the remaining power value of the terminal is detected.

Specifically, if the backlight control function is in the on state, the remaining power value of the terminal may be periodically detected at a set time interval, so that the terminal may determine whether the terminal is in the low power mode according to the detected remaining power value.

Step 12: When detecting that the remaining power value is lower than or equal to the power threshold, lower the gray level of the screen background image to update the screen display screen.

The power threshold may be an experience value pre-stored in the terminal, which may be preset in the terminal before the mobile terminal leaves the factory, or may be set according to user operations.

Referring to FIG. 2, the current display image corresponding to the screen display screen may include a background image 01 and a content layer 02, and the current display image may be an application icon interface, or an image of another application interface such as an instant messaging application, a calendar, a short message, or a note.

Specifically, after detecting the remaining power value of the terminal, comparing the remaining power value of the terminal with the power threshold, if the remaining power value of the terminal is lower than or equal to the power threshold, determining that the terminal is in the low power mode; otherwise, determining the terminal In normal mode.

The backlight control function saves the power of the dark picture (low grayscale picture) better than the light picture of the light picture (high gray level picture), because the gray picture space of the picture itself can be increased, so the corresponding The space for lowering the brightness of the backlight is also large. Specifically, if the terminal is in the low power mode, the gray scale of the screen background image is reduced, and the gray scale of the screen display screen including the screen background image and the content layer can be reduced, thereby improving the grayscale lifting space of the screen display screen, correspondingly Ground can increase the room for the brightness of the screen backlight.

Step 13. Adjust the grayscale and the brightness of the screen backlight on the updated screen display screen based on the backlight control function.

Specifically, the backlight control function has the same grayscale increase range as the screen backlight brightness reduction on the updated screen display screen, so that the brightness of the image is substantially consistent before and after the processing.

In the process of the backlight control function being turned on, the embodiment of the present invention detects the remaining power value of the terminal, and when the remaining power value is lower than or equal to the power threshold, the gray scale of the screen backlight image is reduced, and the screen display screen can be improved. The grayscale increases the space, and then adjusts the grayscale and screen backlight brightness of the screen display based on the backlight control function. The reduction of the brightness of the screen backlight can be increased, so that the power consumption of the terminal can be reduced.

In an embodiment, exemplarily, reducing the grayscale of the background image of the screen includes:

At least one power saving background image is preset in the terminal, and the power saving background image is used to reduce the gray scale of the currently displayed image in the screen. The grayscale threshold may be an empirical value determined by the user, or may be determined according to a history of the backlight control function, such as grayscale values of the historical image content for each historical image content displayed on the screen, and backlight control. The screen backlight brightness adjusted for the historical image is determined, each target history image whose screen backlight brightness is higher than the brightness threshold is determined, and the minimum gray level value among the gray scale values of each target history image may be used as the gray level threshold. The gray scale of the screen background image can be directly reduced by the preset power saving background image, which can not only effectively improve the brightness reduction of the screen backlight, but also improve the update efficiency of the screen display screen, thereby improving the efficiency of switching the background gray scale for power saving.

In an embodiment, exemplarily, selecting and updating a target background image of the screen from the preset at least one power saving background image may include:

The type of the scene in which the screen is located may be determined according to at least one of the display frame feature, the user behavior feature, or the camera state of the screen, and the display frame feature may be the brightness, transparency, hue, contrast, and saturation of the screen display frame. Or ambiguity, etc. For example, if the current frame rate of the screen is zero, it is determined that the screen is in a static picture scene; if the camera of the terminal is in the startup state, it is determined that the screen is in the picture preview scene; if the currently active active process is a video class process or a game class process And the current layer is a dynamic layer, then it is determined that the screen is in a dynamic scene.

Specifically, when the screen is in different scenes, different power saving background images are used, and the power consumption of the terminal can be further reduced under the premise of taking into account the screen display effect, thereby extending the terminal life time.

In an embodiment, exemplarily, reducing the gray level of the background image of the screen may further include:

The initial background image refers to the background image of the currently displayed image. The preset value corresponding to the initial background image may be one or more. For example, the current display image is divided into multiple sub-regions, and the grayscale mean values of the sub-regions are respectively counted, and the values corresponding to the grayscale mean values of the sub-regions are determined according to the mapping relationship between the pre-established grayscale mean values and the preset numerical values. The higher the gray level mean value in the mapping relationship, the higher the preset value.

On the basis of the foregoing embodiment, referring to FIG. 3, in order to further improve the power saving effect, the method for switching the background gray scale to save power may further include:

Step 24: When a charging event is detected, and the remaining power value of the screen is higher than the power threshold, the initial background image is re-used as the target background image of the screen.

After detecting that the terminal is switched from the low power mode to the non-low power mode, the initial background image is re-used as the target background image of the screen. The initial background image may be a background image with high user satisfaction that is predetermined or personalized according to user operations.

Step 25: Perform grayscale and screen backlight brightness adjustment on the updated screen display screen based on the backlight control function.

It should be noted that the functions of step 25 and step 13 are the same, and step 25 may be omitted. The grayscale and screen backlight brightness adjustment may be performed based on the backlight control function each time the screen background image is updated, that is, each time the screen display screen is updated. Just fine.

Specifically, the backlight control function adjusts the grayscale and the screen backlight brightness on the screen display screen with the initial background image as the background, and can provide the screen display screen for the user, thereby improving user satisfaction.

The embodiment of the present application further provides a device for switching background gray scales for power saving, including:

In an embodiment, the screen grayscale reduction module is specifically configured to:

In an embodiment, after the background image recovery module is configured to select and update the target background image of the screen from the preset at least one power saving background image, the charging event is detected, and the remaining power value of the screen is higher than When the power threshold is reached, the initial background image is re-used as the target background image of the screen.

In an embodiment, the backlight adjustment module is based on the backlight control function, and the grayscale increase range of the updated screen display screen is the same as the screen backlight brightness reduction amplitude.

In an embodiment, the screen grayscale reduction module is further configured to: determine a scene type in which the screen is located according to at least one of a display frame feature, a user behavior feature, or a camera state of the screen.

FIG. 4 is a schematic structural diagram of an apparatus for switching a background gray scale to perform power saving according to an embodiment of the present disclosure, where the apparatus may be configured in a mobile terminal. As shown in FIG. 4, the specific structure of the apparatus for switching the background gray scale to save power may include:

The power detecting module 31 is configured to detect a remaining power value of the terminal if the backlight control function is in an on state;

The screen grayscale reduction module 32 is configured to: when detecting that the remaining power value is lower than or equal to the power threshold, reduce a grayscale of the screen background image to update the screen display screen;

The backlight adjustment module 33 is configured to perform grayscale and screen backlight brightness adjustment on the updated screen display screen based on the backlight control function.

In an embodiment, the screen grayscale reduction module 31 may be specifically used to:

In an embodiment, the device may further include:

a background image recovery module, configured to: after selecting and updating a target background image of the screen from the preset at least one power saving background image, when a charging event is detected, and a remaining power value of the screen is higher than the power threshold The initial background image is re-used as the target background image of the screen.

In an embodiment, the screen grayscale reduction module 31 is specifically configured to: subtract the grayscale of each pixel in the initial background image by a preset value.

In an embodiment, the screen grayscale reduction module 31 is further configured to: determine a scene type in which the screen is located according to at least one of a display frame feature, a user behavior feature, or a camera state of the screen.

In an embodiment, the backlight adjustment module 33 performs the same grayscale increase amplitude on the updated screen display screen as the backlight backlight brightness reduction based on the backlight control function.

The method for switching the background gray scale to save power, and the method for switching the background gray scale to save power provided by any embodiment of the present application belong to the same inventive concept, and can perform the switching background gray scale provided by any embodiment of the present application. The electrical method has the corresponding functional modules and beneficial effects of performing the method of switching the background gray scale to save power. For the technical details that are not described in detail in this embodiment, refer to the method for switching the background gray scale to save power provided by any embodiment of the present application. An embodiment of the present application provides an electronic device, which may include a memory, a processor, and a computer program stored on the memory and executable on the processor. For example, perform the following steps:

The electronic device may be a device such as a mobile terminal, such as a mobile phone or a tablet computer.

FIG. 5 is a schematic structural diagram of a mobile terminal according to an embodiment of the present disclosure. As shown in FIG. 5, the illustrated smart phone 400 may include: a memory 401 and a central processing unit (Central). Processing Unit, hereinafter referred to as CPU) 402, peripheral interface 403, RF circuit 405, audio circuit 406, speaker 411, power management chip 408, input/output (I/O) subsystem 409, other input/control devices 410, and external ports 404, these components communicate via one or more communication buses or signal lines 407.

It should be understood that the illustrated smartphone 400 is merely one example of a mobile terminal, and that the smartphone 400 may have more or fewer components than those shown in the figures, two or more components may be combined, or Can have different component configurations. The various components shown in the figures can be implemented in hardware, software, or a combination of hardware and software, including one or more signal processing and/or application specific integrated circuits.

The following describes a smart phone for switching the background gray scale for power saving provided in this embodiment.

Memory 401: The memory 401 can be accessed by a CPU (abbreviated as processor) 402, a peripheral interface 403, etc., and the memory 401 can include a high speed random access memory, and can also include a non-volatile memory, such as one or more disk storage devices, Flash memory devices, or other volatile solid-state memory devices.

Peripheral interface 403, which can connect the input and output peripherals of the device to CPU 402 and memory 401.

I/O Subsystem 409: I/O Subsystem 409 can connect input and output peripherals on the device, such as touch screen 402 and other input/control devices 410, to peripheral interface 403. The I/O subsystem 409 can include a display controller 4091 and one or more input controllers 4092 for controlling other input/control devices 410. Wherein, one or more input controllers 4092 receive electrical signals from other input/control devices 410 or transmit electrical signals to other input/control devices 410, and other input/control devices 410 may include physical buttons (press buttons, rocker buttons, etc.) ), dial, slide switch, joystick or click on the wheel. It is worth noting that the input controller 4092 can be connected to any of the following: a keyboard, an infrared port, a USB interface, and a pointing device such as a mouse.

Touch screen 412: The touch screen 412 is an input interface and an output interface between the user terminal and the user, and displays the visual output to the user. The visual output may include graphics, text, icons, or video.

Display controller 4091 in I/O subsystem 409 receives electrical signals from touch screen 412 or transmits electrical signals to touch screen 412. The touch screen 412 detects the contact on the touch screen, and the display controller 4091 converts the detected contact into an interaction with the user interface object displayed on the touch screen 412, ie, realizes human-computer interaction, and the user interface object displayed on the touch screen 412 may be running. The icon of the game, the icon of the network to the corresponding network, and the like. It is worth noting that the device may also include a light mouse, which is a touch sensitive surface that does not display a visual output, or an extension of a touch sensitive surface formed by the touch screen.

The RF circuit 405 is mainly used for establishing communication between the mobile phone and the wireless network (ie, the network side), and realizing data reception and transmission between the mobile phone and the wireless network. For example, sending and receiving short messages, emails, and the like. Specifically, the RF circuit 405 receives and transmits an RF signal, which is also referred to as an electromagnetic signal, and the RF circuit 405 converts the electrical signal into an electromagnetic signal or converts the electromagnetic signal into an electrical signal, and through the electromagnetic signal and communication network and other devices Communicate. RF circuitry 405 may include known circuitry for performing these functions including, but not limited to, an antenna system, an RF transceiver, one or more amplifiers, a tuner, one or more oscillators, a digital signal processor, a CODEC chip Group, user identification module (Subscriber Identity Module, SIM) and more.

The audio circuit 406 is mainly used to receive audio data from the peripheral interface 403, convert the audio data into an electrical signal, and transmit the electrical signal to the speaker 411.

The speaker 411 is configured to restore the voice signal received by the mobile phone from the wireless network through the RF circuit 405 to sound and play the sound to the user.

The power management chip 408 is used for power supply and power management of the hardware connected to the CPU 402, the I/O subsystem, and the peripheral interface.

The CPU 402 provided by the embodiment of the present application implements the following steps when executing the computer program:

In an embodiment, the processor 402 is configured to perform the following steps when reducing the grayscale of the background image of the screen:

In an embodiment, when selecting and updating a target background image of the screen from the preset at least one power saving background image, the processor 402 is configured to perform the following steps:

In an embodiment, after selecting and updating the target background image of the screen from the preset at least one power saving background image, the processor 402 is further configured to perform the following steps:

A person skilled in the art may understand that all or part of the various steps of the foregoing embodiments may be performed by a program to instruct related hardware. The program may be stored in a computer readable storage medium, and the storage medium may include: Read only memory (ROM, Read Only Memory), Random Access Memory (RAM), disk or CD.

The above are only the preferred embodiments of the present application and the technical principles applied thereto. A person skilled in the art will understand that the present application is not limited to the specific embodiments described herein, and that various changes, modifications and substitutions can be made by those skilled in the art without departing from the scope of the invention. Therefore, although the present application has been described in detail by the above embodiments, the present application is not limited to the above embodiments, and other equivalent embodiments may be included without departing from the concept of the present application. The scope is determined by the scope of the appended claims.

Claims

A method for switching background gray scales for power saving, wherein:

If the backlight control function is in the on state, detecting the remaining power value of the terminal;

When detecting that the remaining power value is lower than or equal to the power threshold, lowering the gray level of the screen background image to update the screen display screen;

The grayscale and screen backlight brightness are adjusted on the updated screen display screen based on the backlight control function.
The method of claim 1 wherein reducing the grayscale of the background image of the screen comprises:

Selecting and updating a target background image of the screen from the preset at least one power saving background image, wherein the grayscale of the power saving background image is less than a grayscale threshold.
The method of claim 2, wherein selecting and updating a target background image of the screen from the preset at least one power saving background image comprises:

If the screen is in a static picture type scene, the first power saving background image is determined as the target background image of the screen;

If the screen is in the picture preview scene, the second power saving background image is determined as the target background image of the screen;

If the screen is in a dynamic scene, the third power saving background image is determined as the target background image of the screen;

The gray level of the first power saving background image, the second power saving background image, and the third power saving background image are sequentially decreased.
The method according to claim 2, wherein after selecting and updating the target background image of the screen from the preset at least one power saving background image, the method comprises:

Upon detecting a charging event and the remaining charge value of the screen is above the power threshold, the initial background image is re-used as the target background image for the screen.
The method of claim 1 wherein reducing the grayscale of the background image of the screen comprises:

The gray scale of each pixel in the initial background image is subtracted from the preset value.
The method of claim 1, wherein the grayscale boosting amplitude of the updated screen display screen is the same as the screen backlight luminance reduction amplitude based on the backlight control function.
The method of claim 3, wherein selecting and updating the target background image of the screen from the preset at least one power saving background image further comprises:

The type of scene in which the screen is located is determined according to at least one of the display frame characteristics, the user behavior characteristics, or the camera status of the screen.
A device for switching background gray scales for power saving, wherein:

The power detecting module is configured to detect a remaining power value of the terminal if the backlight control function is in an open state;

a screen grayscale reduction module, configured to reduce a grayscale of the screen background image to update the screen display screen when detecting that the remaining power value is lower than or equal to the power threshold;

The backlight adjustment module is configured to adjust the grayscale and screen backlight brightness of the updated screen display screen based on the backlight control function.
The device according to claim 8, wherein the screen grayscale reduction module is specifically configured to:

Selecting and updating a target background image of the screen from the preset at least one power saving background image, wherein the grayscale of the power saving background image is less than a grayscale threshold.
The device according to claim 9, wherein the screen grayscale reduction module is specifically configured to:

If the screen is in a static picture type scene, the first power saving background image is determined as the target background image of the screen;

If the screen is in the picture preview scene, the second power saving background image is determined as the target background image of the screen;

If the screen is in a dynamic scene, the third power saving background image is determined as the target background image of the screen;

The gray level of the first power saving background image, the second power saving background image, and the third power saving background image are sequentially decreased.
The apparatus of claim 9 comprising:

a background image recovery module, configured to: after selecting and updating a target background image of the screen from the preset at least one power saving background image, when a charging event is detected, and a remaining power value of the screen is higher than the power threshold The initial background image is re-used as the target background image of the screen.
The device according to claim 8, wherein the screen grayscale reduction module is specifically configured to:

The gray scale of each pixel in the initial background image is subtracted from the preset value.
The apparatus according to claim 8, wherein the backlight adjustment module adjusts the grayscale increase amplitude of the updated screen display screen to be the same as the screen backlight luminance reduction amplitude based on the backlight control function.
The apparatus of claim 10, wherein the screen grayscale reduction module is further configured to determine a scene type in which the screen is located according to at least one of a display frame feature, a user behavior feature, or a camera state of the screen.
A storage medium, wherein the storage medium stores a plurality of instructions adapted to be loaded by a processor to perform the method of any one of claims 1-7.
An electronic device includes a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor executes the computer program to implement the following steps:

If the backlight control function is in an on state, detecting a remaining power value of the electronic device;

When detecting that the remaining power value is lower than or equal to the power threshold, lowering the gray level of the screen background image to update the screen display screen;

The grayscale and screen backlight brightness are adjusted on the updated screen display screen based on the backlight control function.
The electronic device of claim 16, wherein the processor is configured to perform the following steps when reducing grayscale of the screen background image:

Selecting and updating a target background image of the screen from the preset at least one power saving background image, wherein the grayscale of the power saving background image is less than a grayscale threshold.
The electronic device of claim 16, wherein the processor is configured to perform the following steps when selecting and updating a target background image of the screen from the preset at least one power saving background image:

If the screen is in a static picture type scene, the first power saving background image is determined as the target background image of the screen;

If the screen is in the picture preview scene, the second power saving background image is determined as the target background image of the screen;

If the screen is in a dynamic scene, the third power saving background image is determined as the target background image of the screen;

The gray level of the first power saving background image, the second power saving background image, and the third power saving background image are sequentially decreased.
The electronic device according to claim 17, wherein after selecting and updating a target background image of the screen from the preset at least one power saving background image, the processor is further configured to perform the following steps:

Upon detecting a charging event and the remaining charge value of the screen is above the power threshold, the initial background image is re-used as the target background image for the screen.
The electronic device of claim 16, wherein the processor is configured to perform the following steps when reducing grayscale of the screen background image:

The gray scale of each pixel in the initial background image is subtracted from the preset value.