Screen-off control method and device, equipment and storage medium

Abstract

The embodiment of the invention relates to the technical field of display equipment, and discloses a screen turn-off control method and device, equipment and a storage medium, and the scheme comprises the following steps: obtaining first illumination intensity of a surrounding environment detected by an ambient light sensor; if the first illumination intensity meets the preset shielding triggering condition, the ultrasonic sensor is controlled to transmit an ultrasonic signal, and the ultrasonic signal returns to the ultrasonic sensor after reaching the auxiliary screen; a signal set is obtained, the signal set comprises at least one pair of ultrasonic receiving and transmitting signals, the pair of ultrasonic receiving and transmitting signals comprises ultrasonic signals and ultrasonic echo signals, and the ultrasonic echo signals can be signals obtained after the ultrasonic signals arrive at the auxiliary screen and then return to the ultrasonic sensor; detecting whether a screen area of the main screen has a shielding object according to the signal set; and if yes, controlling the main screen to execute a screen turn-off operation. According to the scheme, whether the main screen in the blackboard needs to be turned off or not can be jointly judged by detecting the ambient light and the ultrasonic waves at the same time, the accuracy and stability of automatic screen turning off are improved, and power consumption of the blackboard is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of display devices, and in particular to a screen off control method, device, equipment and storage medium. Background Art

[0002] Blackboard is the most traditional and widely used teaching media in classroom teaching, and is an indispensable educational equipment in the classroom. With the continuous development of information technology, it has evolved into a multifunctional smart blackboard. The wisdom of the smart blackboard is to connect the blackboard with various hardware and software devices to form a systematic teaching ecological environment, providing comprehensive services and various functions for teaching.

[0003] At present, smart blackboards usually include a main screen and a secondary screen, wherein the main screen is a display screen or a projection screen, and the secondary screen is a writing board. The smart blackboard can detect the light intensity through the ambient light sensor and automatically turn off the screen. However, due to the installation structure error between the main screen and the secondary screen, even if the main screen and the secondary screen are closed and stacked, there is a gap on the side between the main screen and the secondary screen, and the external ambient light can penetrate into the main screen and the secondary screen through the gap on the side. Although the main screen and the secondary screen have been closed and stacked, the light sensor detects that the current light intensity is still greater than the preset threshold, so that the main screen cannot be prompted to enter the screen-off state. Summary of the invention

[0004] One purpose of an embodiment of the present invention is to provide a screen off control method, device, equipment and storage medium. This solution can simultaneously determine whether the blackboard needs to turn off the screen through ambient light detection and ultrasonic detection, thereby improving the accuracy and stability of automatic screen off and reducing the power consumption of the blackboard itself.

[0005] In a first aspect, a screen off control method is provided, which is applied to a main screen of a blackboard, wherein the blackboard further includes a secondary screen, and the secondary screen is movable relative to the main screen, wherein the main screen is provided with an ambient light sensor and an ultrasonic sensor, and comprises:

[0006] Acquire a first light intensity of a surrounding environment detected by the ambient light sensor;

[0007] If the first light intensity meets the preset occlusion trigger condition, the ultrasonic sensor is controlled to emit an ultrasonic signal, and the ultrasonic signal returns to the ultrasonic sensor after reaching the secondary screen;

[0008] Acquire a signal set, the signal set including at least one pair of ultrasonic transceiver signals, the pair of ultrasonic transceiver signals including an ultrasonic signal and an ultrasonic echo signal, the ultrasonic echo signal may be a signal returned to the ultrasonic sensor after the ultrasonic signal reaches the secondary screen;

[0009] Detecting whether there is an obstruction in the screen area of ​​the main screen according to the signal set;

[0010] If it exists, control the main screen to perform the screen off operation.

[0011] In combination with the first aspect, in a possible implementation method, the signal set includes a first ultrasonic transceiver signal and a second ultrasonic transceiver signal, and detecting whether there is an obstruction in the screen area of ​​the main screen based on the signal set includes: determining a first distance based on the first ultrasonic transceiver signal; determining a second distance based on the second ultrasonic transceiver signal; calculating the difference between the first distance and the second distance; and detecting whether there is an obstruction in the screen area of ​​the main screen based on the difference.

[0012] In combination with the first aspect, in a possible implementation method, it also includes: if the difference is within a first preset range, determining that there is an obstruction in the screen area of ​​the main screen; if the difference is not within the first preset range, determining that there is no obstruction in the screen area of ​​the main screen.

[0013] In combination with the first aspect, in a possible implementation, the blackboard includes a camera, and the camera is arranged in the main screen. Before determining that there is an obstruction in the screen area of ​​the main screen, the screen off control method also includes: acquiring an environmental image taken by the camera; extracting a contour area based on the environmental image; judging whether the contour area matches the contour of the secondary screen; if so, determining that there is an obstruction in the screen area of ​​the main screen.

[0014] In combination with the first aspect, in a possible implementation method, it also includes: determining whether the first light intensity is less than or equal to a first preset light threshold, or whether the first light intensity is greater than or equal to a second preset light threshold; if so, determining that the light intensity meets a preset occlusion trigger condition.

[0015] In combination with the first aspect, in a possible implementation, controlling the main screen to perform a screen off operation includes: generating a screen off notification; sending the screen off notification to the main screen, so that the main screen enters a screen off state according to the screen off notification.

[0016] In combination with the first aspect, in a possible implementation, if present, before controlling the main screen to perform a screen-off operation, the method further includes: obtaining a second light intensity detected by the ambient light sensor; if the difference between the first light intensity and the second light intensity is within a second preset range, controlling the main screen to perform a screen-off operation.

[0017] In a second aspect, a screen off control device is provided, which is applied to a main screen of a blackboard, wherein the blackboard further includes a secondary screen, and the secondary screen can move relative to the main screen, wherein the main screen is provided with an ambient light sensor and an ultrasonic sensor, and comprises:

[0018] An acquisition unit, used for acquiring a first light intensity of a surrounding environment detected by the ambient light sensor;

[0019] A control unit, used for controlling the ultrasonic sensor to transmit an ultrasonic signal, wherein the ultrasonic signal reaches the secondary screen and then returns to the ultrasonic sensor;

[0020] The acquisition unit is further used to acquire a signal set, wherein the signal set includes at least one pair of ultrasonic transceiver signals, wherein the pair of ultrasonic transceiver signals includes an ultrasonic signal and an ultrasonic echo signal, wherein the ultrasonic echo signal may be a signal returned to the ultrasonic sensor after the ultrasonic signal reaches the secondary screen;

[0021] A detection unit, configured to detect whether there is an obstruction in the screen area of ​​the main screen according to the signal set;

[0022] The control unit is also used to control the main screen to perform a screen off operation if any.

[0023] In a third aspect, an embodiment of the present invention provides a main screen, comprising: a display module; an ambient light sensor, arranged on the display module, for detecting a first light intensity of the surrounding environment; an ultrasonic sensor, arranged on the display module, for transmitting an ultrasonic signal; a memory; a processor, respectively connected to the display module, the ambient light sensor and the memory, the processor being used to execute one or more computer programs stored in the memory, and when the processor executes the one or more computer programs, the computer device implements the method described in the first aspect.

[0024] In a fourth aspect, an embodiment of the present invention provides a computer device, including:

[0025] at least one processor; and,

[0026] a memory communicatively connected to the at least one processor; wherein,

[0027] The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method according to the first aspect.

[0028] In a fifth aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, wherein the computer program includes program instructions, and when the program instructions are executed by a processor, the processor executes the method as described in the first aspect.

[0029] In the scheme implemented by the above-mentioned screen-off control method, device, equipment and storage medium, the main screen used for the blackboard first obtains the first light intensity of the surrounding environment detected by the ambient light sensor. If the first light intensity meets the preset occlusion trigger condition, the ultrasonic sensor is controlled to emit an ultrasonic signal, and the ultrasonic signal returns to the ultrasonic sensor after reaching the secondary screen. Secondly, a signal set is obtained, and the signal set includes at least one pair of ultrasonic transceiver signals, and the pair of ultrasonic transceiver signals includes an ultrasonic signal and an ultrasonic echo signal. The ultrasonic echo signal can be a signal returned to the ultrasonic sensor after the ultrasonic signal reaches the secondary screen. Then, according to the signal set, it is detected whether there is an obstruction in the screen area of ​​the main screen. Finally, if there is, the main screen is controlled to perform the screen-off operation. This solution detects the current ambient light intensity of the blackboard's main screen and makes a preliminary occlusion judgment. After the ambient light intensity reaches the requirement, it starts the secondary occlusion judgment, that is, it uses ultrasonic detection to determine whether the secondary screen is blocked in the main screen area. If the ultrasonic detection also determines that the current secondary screen is blocking the main screen, a screen off notification is sent. That is, through two occlusion detections, it can accurately determine whether the current main screen needs to be turned off, thereby improving the accuracy of the screen off and avoiding the occurrence of accidental screen off. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0031] Figure 1A It is a structural schematic diagram of a blackboard in one embodiment of the present invention;

[0032] Figure 1B is a schematic diagram of the hardware structure of a main screen in one embodiment of the present invention;

[0033] Figure 1C This is a schematic diagram of sensor connection in one embodiment of the present invention;

[0034] Figure 2 is a flow chart of a screen-off control method in one embodiment of the present invention;

[0035] Figure 3 is a schematic structural diagram of a screen off control device in one embodiment of the present invention;

[0036] Figure 4 Schematic diagram of the structure of a computer device in one embodiment of the present invention DETAILED DESCRIPTION

[0037] In order to make the purpose, technical scheme and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0038] It should be noted that, if there is no conflict, the various features in the embodiments of the present invention can be combined with each other, all within the scope of protection of the present invention. In addition, although the functional modules are divided in the device schematic diagram and the logical order is shown in the flow chart, in some cases, the steps shown or described can be performed in a different order from the module division in the device or the flow chart. Furthermore, the words "first", "second", "third", etc. used in the present invention do not limit the data and execution order, but only distinguish the same items or similar items with basically the same functions and effects.

[0039] The present invention is described in detail below through specific embodiments.

[0040] The technical solution of this application can be applied to various teaching scenarios or meeting scenarios, etc.

[0041] The technical solution of the present application can be specifically applied in educational classrooms, wherein the blackboard can be a computer device with multifunctional imaging functions such as display, broadcasting, and recording. For ease of understanding, the blackboard of the present application is first introduced.

[0042] See also Figure 1A , Figure 1A A schematic diagram of the structure of a blackboard provided in an embodiment of the present application, wherein the schematic diagram of the structure of the blackboard can be referred to Figure 1A ,exist Figure 1A Area A and area B in the middle are secondary screens. Figure 1A The middle C area is the main screen. In the blackboard in this solution, the position of the main screen C is fixed, and the sub-screen A or B can be moved to the main screen C through a movable track. The above movable track can be installed on the upper and lower sides of the sub-screen A or B, and the movement of the sub-screen A or B can be automatic or based on manual operation, which is not the only limitation here.

[0043] The hardware diagram of the main screen of the blackboard can be found in Figure 1B ,exist Figure 1BThe main screen 10 of the middle blackboard includes a display module 20, a memory 30, and a processor 40, wherein an ambient light sensor 50, an ultrasonic sensor 60, and a camera module 70 are arranged on the display module. The display module 20 is used to display video images or courseware; the processor 40 and the memory 30 are devices for storing and processing signals of various sensors, such as processing the illumination information collected by the ambient light sensor 50, or processing the ultrasonic signal information collected by the ultrasonic sensor 60. The ambient light sensor 50 is used to monitor the ambient illumination conditions and is arranged on the display module 20; the ultrasonic sensor 60 is arranged on the display module and is used to emit ultrasonic signals; therefore, the camera module 70 is used to monitor and collect image data of the surrounding environment in real time.

[0044] The position of the sensor placed in the blackboard depends on the design, size and application requirements of the blackboard, and the following factors may be considered: the size and shape of the blackboard, the type and size of the obstructing object, the accuracy and detection range of various sensors, changes in lighting conditions, etc. The ambient light sensor 50 and the ultrasonic sensor 60 may be determined according to specific design and application requirements. For example, the ambient light sensor 50 and the ultrasonic sensor 60 may be placed together at the lower right corner of the display module 20; or the ultrasonic sensor 60 may be placed at the top, edge, or bottom of the display module 20; or the ambient light sensor 50 may be placed at the top center of the display module 20, and the camera module 70 may be placed at the top center of the display module 20, at the edge of the display module 20, or at the side or bottom of the display module 20, which is not limited here.

[0045] The above-mentioned ambient light sensor 50 or ultrasonic sensor 60 can be Figure 1C The connection is as follows: the ambient light sensor 50 is generally connected to the main chip using the I2C bus, and data communication is achieved through the I2C protocol. I2C is a serial communication bus that has the characteristics of bidirectional data transmission and reception and multiple devices sharing the same bus. It can connect multiple devices for communication and has relatively high transmission efficiency and reliability. The ambient light sensor 50 generally has an I2C address. The main chip specifies the address through the I2C bus, and can read and write data on the sensor to obtain illumination data.

[0046] The ultrasonic sensor 60 generally only needs to be connected to the main chip through GPIO to realize the collection of distance data. GPIO is a general input and output port that can realize the input and output of digital signals. The ultrasonic sensor 60 outputs a trigger signal to a certain GPIO port, and then measures the time it takes for another GPIO port to receive the rebound signal, thereby calculating the distance between the obstruction and the entire machine. From the software level, the Linux driver in the blackboard collects data from the ambient light sensor 50 through the I2C bus, and the data from the ultrasonic sensor 60 is read through the GPIO port. When the data collection is completed, the data will be uploaded for processing.

[0047] In view of this, the present application proposes a screen off control method to solve the above problem, which is described in detail below.

[0048] See also Figure 2 , Figure 2 A flow chart of a screen off control method provided in an embodiment of the present invention is applied to a main screen of a blackboard, wherein the blackboard further comprises a secondary screen, and the secondary screen can move relative to the main screen. The main screen is provided with an ambient light sensor and an ultrasonic sensor, and the method comprises the following steps:

[0049] S10, obtaining a first light intensity of a surrounding environment detected by the ambient light sensor.

[0050] Among them, the ambient light sensor is used to collect lighting data of the surrounding environment, and can be placed in the lower right corner of the main screen or in the top center of the main screen. There is no unique limitation on the placement position of the ambient light sensor here.

[0051] The first light intensity is collected by an ambient light sensor arranged in the main screen, and the first light intensity is a measured value of relative light intensity rather than absolute light intensity.

[0052] The above-mentioned surrounding environment is the environment of the maximum range area that can be collected by the ambient light sensor. The collection range of the ambient light sensor usually varies depending on the sensor model and manufacturer, and is not the only limitation here.

[0053] It can be seen that the ambient light sensor set on the main screen can be used to make a preliminary judgment on the lighting of the surrounding environment, and then flexibly determine whether to control the ultrasonic sensor to make a secondary judgment on whether to turn off the screen according to the different light intensities.

[0054] S20: If the first light intensity meets a preset occlusion trigger condition, control the ultrasonic sensor to emit an ultrasonic signal, and the ultrasonic signal returns to the ultrasonic sensor after reaching the secondary screen.

[0055] Among them, the above-mentioned preset occlusion trigger condition can be when the above-mentioned first light intensity is between 10 and 20 lux, which is usually considered to be a relatively dim lighting condition, that is, abnormal lighting, and the ultrasonic sensor of the blackboard is controlled to emit an ultrasonic signal. When the above-mentioned first light intensity is not between 10 and 20 lux, there is no need to control the ultrasonic sensor of the blackboard to emit an ultrasonic signal.

[0056] Specifically, when any secondary screen completely covers the main screen, the first light intensity is between 10 and 20 lux, which means that the condition for starting the ultrasonic sensor is determined to be met, and the ultrasonic sensor is further controlled to emit an ultrasonic signal; when the moving areas of multiple secondary screens are merged and completely cover the main screen, the occlusion trigger condition of the first light intensity between 10 and 20 lux is also met; when the secondary screen cannot completely cover the main screen, the ambient light sensor will detect side leakage light, and therefore the preset occlusion trigger condition cannot be met, and there is no need to turn on the ultrasonic sensor.

[0057] Optionally, if any first position of the secondary screen does not exceed the center line area of ​​the main screen, the ultrasonic sensor is not controlled to emit ultrasonic signals, and the light intensity in the first area is continuously detected. When the secondary screen does not block the main screen, it is determined that the current lighting may be caused by human movement and weather environment, and does not meet the situation of turning off the screen due to blocking obstacles.

[0058] Among them, the ultrasonic signals sent by the ultrasonic sensor are ultrasonic pulse signals. These pulse signals propagate in the form of ultrasonic waves, pass through the air and propagate along a straight path to the direction of the secondary screen. After the ultrasonic signal reaches the secondary screen, it interacts with the object, and a part of the ultrasonic signal is reflected back by the object to form an echo signal. The ultrasonic sensor receives the echo signal and converts it into an electrical signal. Since the time delay of the echo is proportional to the distance, the electrical signal contains information about the distance between the object and the secondary screen.

[0059] It can be seen that the ultrasonic sensor can be flexibly started according to the different ambient light intensities, and then secondary detection can be performed through ultrasound, thereby improving the accuracy and flexibility of screen off.

[0060] S30. Acquire a signal set, where the signal set includes at least one pair of ultrasonic transceiver signals, where the pair of ultrasonic transceiver signals includes an ultrasonic signal and an ultrasonic echo signal, where the ultrasonic echo signal may be a signal returned to the ultrasonic sensor after the ultrasonic signal reaches the secondary screen.

[0061] The ultrasonic echo signal may be a signal returned to the ultrasonic sensor after the ultrasonic signal reaches the secondary screen, or may be a signal returned to the ultrasonic sensor after the ultrasonic signal encounters an obstruction.

[0062] Specifically, when the preset occlusion trigger condition is met, the ultrasonic sensor in the main screen is activated and sends ultrasonic signals to the surroundings or in front of the main screen. The received echo signal may be the echo signal returned after reaching the sub-screen; or it may be the echo signal returned when encountering other obstructions, such as boxes and other light-blocking objects placed in front of the main screen.

[0063] Among them, according to the above-mentioned ultrasonic detection function, the distance between the obstruction and the main screen can be obtained according to the emitted ultrasonic wave, the rebounded ultrasonic wave (echo) and the time difference between them. Specifically as follows: the ultrasonic sensor emits ultrasonic waves in a certain direction, and starts timing at the same time as the emission time. The ultrasonic wave propagates in the air, and returns immediately when it encounters an obstacle on the way. The ultrasonic sensor stops timing immediately after receiving the reflected wave. The propagation speed of ultrasonic waves in the air is 330m / s. According to the time t recorded by the timer, the distance (s) from the emission point to the obstacle can be calculated, that is: s=330t / 2. This is the so-called time difference ranging method. The principle of ultrasonic ranging is to use the known propagation speed of ultrasonic waves in the air, measure the time it takes for the sound wave to be reflected back after encountering an obstacle after emission, and calculate the actual distance from the emission point to the obstacle based on the time difference between emission and reception.

[0064] S30. Detect whether there is an obstruction in the screen area of ​​the main screen according to the signal set.

[0065] After the signal set is acquired, the screen area of ​​the main screen is detected to see if there is an obstruction. This step is based on ultrasonic occlusion detection, which is used to determine whether an object is in the optical path of the main screen, thereby causing occlusion. By analyzing the ultrasonic signal and the corresponding ultrasonic echo signal, the time delay of the ultrasonic signal after it is emitted to reach the secondary screen and return is calculated. This can be used to determine the distance between the obstructing object and the main screen. The time delay of the ultrasonic echo signal is proportional to the distance of the obstructing object.

[0066] It can be seen that ultrasonic-based obstruction detection and response can quickly and accurately determine whether there is an obstruction at the moment, thereby improving the flexibility and accuracy of screen off.

[0067] S40: If yes, control the main screen to perform screen off operation.

[0068] This solution detects the current ambient light intensity of the blackboard's main screen and makes a preliminary occlusion judgment. After the ambient light intensity reaches the requirement, it starts the secondary occlusion judgment, that is, it uses ultrasonic detection to determine whether the secondary screen is blocked in the main screen area. If the ultrasonic detection also determines that the current secondary screen is blocking the main screen, a screen off notification is sent. That is, through two occlusion detections, it can accurately determine whether the current main screen needs to be turned off, thereby improving the accuracy of the screen off and avoiding the occurrence of accidental screen off.

[0069] In a possible example, the signal set includes a first ultrasonic transceiver signal and a second ultrasonic transceiver signal, and detecting whether there is an obstruction in the screen area of ​​the main screen according to the signal set includes:

[0070] determining a first distance according to the first ultrasonic transceiver signal;

[0071] determining a second distance according to the second ultrasonic transceiver signal;

[0072] calculating a difference between the first distance and the second distance;

[0073] Whether there is an obstruction in the screen area of ​​the main screen is detected according to the difference.

[0074] There may be a preset time period between the first ultrasonic transceiver signal and the second ultrasonic transceiver signal, and the preset time period may be between 2 and 3 seconds, which is not limited here.

[0075] Among them, whether there is an obstruction in the screen area of ​​the main screen can be judged based on whether the difference falls into the preset area range. The preset area range can be a distance error range of less than 2 cm. The specific error range can be set at the factory or manually set, and is not the only limitation here.

[0076] For example, the distance measured by the first ultrasonic receiving and transmitting signal: the first ultrasonic sensor measures the distance to the obstacle above the main screen to be 30 centimeters (0.3 meters); the distance measured by the second ultrasonic receiving and transmitting signal: the second ultrasonic sensor measures the distance to the obstacle below the main screen to be 20 centimeters (0.2 meters); the distance difference is calculated: the difference is the first distance minus the second distance, that is, 0.3 meters - 0.2 meters = 0.1 meters; the obstruction is detected based on the difference: since the difference is 0.1 meters, which is less than the preset 0.15 meters, it is determined that there is an obstruction in the screen area of ​​the main screen.

[0077] Optionally, the acquired ultrasonic signal may have a ranging error, so mis-measuring may occur. The following specific steps can be performed:

[0078] Get the temperature value of the space where the blackboard is currently located;

[0079] According to the temperature value, the preset formula is substituted to obtain the distance measurement error;

[0080] The distance measurement error is used to update the first distance or the second distance to obtain an updated first distance and second distance.

[0081] Among them, in the formula: r is the ratio of the heat capacity at constant pressure to the heat capacity at constant volume of the gas, which is 1.30 for air, R is the universal constant of the gas, 8.313 kg·mol-1·K-1, M is the molecular weight of the gas, which is 28.8×10-3 kg·mol-1 for air, and T is the absolute temperature, 273K+T℃. The approximate formula is: C=C0+0.607×T℃, in which: C0 is the speed of sound waves at zero degrees, 332m / s; T is the actual temperature (℃).

[0082] For example, when the temperature is 0℃, the ultrasonic speed is 332m / s, and when it is 30℃, it is 340m / s. The change in ultrasonic speed caused by temperature change is 18m / s. If the ultrasonic wave is measured at a distance of 100m at a speed of 0℃ in a 30℃ environment, the measurement error will reach 4m, and the measurement error of 1m will reach 4cm.

[0083] It can be seen that this solution can determine whether there is an obstruction by the distance obtained by ultrasonic ranging, and further obtain a more accurate obstruction distance by compensating for the error of ultrasonic ranging, making this solution more accurate and reliable.

[0084] In one possible example, this also includes:

[0085] If the difference is within a first preset range, it is determined that there is an obstruction in the screen area of ​​the main screen;

[0086] If the difference is not within the first preset range, it is determined that there is no obstruction in the screen area of ​​the main screen.

[0087] Among them, the above-mentioned first preset range can be a distance error range less than 2 cm. The specific error range can be set at the factory or manually set, and is not the only limitation here.

[0088] In one possible example, the blackboard includes a camera, and the camera is arranged in the main screen. Before determining that there is an obstruction in the screen area of ​​the main screen, the screen off control method also includes: acquiring an environmental image taken by the camera; extracting a contour area based on the environmental image; judging whether the contour area matches the contour of the secondary screen; if so, determining that there is an obstruction in the screen area of ​​the main screen.

[0089] The environment image is an image captured by a camera in the main screen. The environment image may be a panoramic image in front of the main screen or an image of a certain area, which is not limited here.

[0090] Optionally, in the above process of extracting the contour area, image preprocessing, denoising, image enhancement and other steps can be first adopted to obtain a clear image that can be used to extract the contour, and then the contour image in the reflected image is extracted through feature point extraction from the processed environmental image, and whether it is a quadrilateral image is identified based on the contour image. The contour area is usually the area in the environmental image where the brightness or color changes significantly. These areas usually correspond to potential obstructing objects. The extracted contour area is compared and matched with the contour of the secondary screen. The contour of the secondary screen is a preset quadrilateral, which serves as a comparison basis. If the contour area in the environmental image matches the contour of the secondary screen, it is determined that there is an obstruction in the screen area of ​​the main screen.

[0091] The above-mentioned contour area is a quadrilateral area.

[0092] It can be seen that the contour image can be used to avoid the erroneous operation of triggering the screen off when the secondary screen is not blocked. The current confirmed blockage of the main screen can be further determined based on the contour image content, thereby improving the accuracy and reliability of blockage detection, thereby improving the accuracy and flexibility of automatic screen off.

[0093] In one possible example, this also includes:

[0094] Determining whether the first light intensity is less than or equal to a first preset light threshold, or whether the first light intensity is greater than or equal to a second preset light threshold;

[0095] If so, it is determined that the light intensity meets the preset shading trigger condition.

[0096] The preset shielding trigger condition may be when the first light intensity is between 10 and 20 lux.

[0097] Among them, the ambient light sensor collects the ambient light in the main screen area. When the external light is too bright or too dark, it may cause the screen to be accidentally turned off. Therefore, the exposure compensation of the external light and the light in the blackboard area can be performed to further obtain the accurate ambient light intensity.

[0098] Optionally, when the first light intensity is less than the first preset light value, which may be lower than 0.020 lux, that is, when it is too dark, the exposure may be increased by performing exposure compensation on the first light intensity to ensure that the screen is not accidentally turned off.

[0099] Optionally, when the first light intensity is greater than the second preset light value, the second preset light value may be lower than 200 lux, that is, when it is too bright, the exposure may be reduced by performing exposure compensation on the first light intensity to ensure that the screen is not accidentally turned off.

[0100] Among them, the above-mentioned increase in exposure and decrease in exposure can be manually set at the factory or based on basic exposure compensation parameters, such as: "EV" is the unit of exposure compensation, and the EV value measures the amount of exposure compensation. A positive EV value indicates an increase in exposure; a negative EV value indicates a decrease in exposure; EV0 indicates normal exposure, and for every increase in EV value by 1, the amount of light intake doubles; for every decrease in EV value by 1, the amount of light intake decreases by half, which is not a unique limitation here.

[0101] It can be seen that by judging whether the first light intensity is under normal light, if not, different light processing is performed for different light intensities, so as to obtain the real light intensity that meets the current scene, thereby avoiding the occurrence of accidental screen off.

[0102] In a possible example, controlling the main screen to perform a screen off operation includes:

[0103] Generate a screen-off notification;

[0104] The screen-off notification is sent to the main screen, so that the main screen enters the screen-off state according to the screen-off notification.

[0105] Optionally, if there is no obstruction, no screen-off notification is sent, and the ambient light intensity is continuously detected.

[0106] Among them, the screen-off operation performed by the screen-off notification can be performed by the background of the blackboard to automatically turn off the screen of the system, or by manual confirmation. There is no sole limitation here.

[0107] Furthermore, a screen-off notification is sent, including:

[0108] Turn on the audio detector to collect audio information in real time;

[0109] The time to start the screen off is determined according to the audio information.

[0110] Optionally, audio analysis can be performed on the audio information to determine that the audio content in the current audio is not teaching content, and the volume and noisiness of the audio information can be further determined. According to the volume and noisiness, the screen off time can be determined. If the volume and noisiness are as high as 60%, the screen will be turned off immediately. If the noisiness is lower than 20%, the display brightness of the main screen can be reduced first, and then the screen will be turned off.

[0111] It can be seen that this solution further performs intelligent control of the screen off according to the audio content, which can improve the reliability of the screen off.

[0112] In a possible example, if present, before controlling the main screen to perform a screen off operation, the method further includes:

[0113] Acquire a second light intensity detected by the ambient light sensor;

[0114] If the difference between the first light intensity and the second light intensity is within a second preset range, the main screen is controlled to perform a screen off operation.

[0115] Among them, the second preset range is the illumination range, which ensures that the obstruction after ultrasonic detection and the obstruction detected by ambient light are under the same obstruction, avoiding the situation of accidental screen shutdown. The illumination range can be 1~4lux, which is not a unique limitation here.

[0116] It can be seen that by performing secondary detection of the ambient light intensity, the accuracy of the screen off is improved, and the inability to accurately turn off the screen when the scene changes is avoided.

[0117] The method of the present application is introduced above, and the device of the present application is introduced below.

[0118] See also Figure 3 , Figure 3 Schematic diagram of the structure of a screen off control device provided in an embodiment of the present application. Figure 3 As shown, the screen off control device is applied to the main screen of the blackboard, and the blackboard also includes a secondary screen, and the secondary screen can move relative to the main screen. It is characterized in that the main screen is provided with an ambient light sensor and an ultrasonic sensor. The screen off control device includes:

[0119] An acquisition unit 301 is used to acquire a first light intensity of a surrounding environment detected by the ambient light sensor;

[0120] A control unit 302, used to control the ultrasonic sensor to transmit an ultrasonic signal, and the ultrasonic signal returns to the ultrasonic sensor after reaching the secondary screen;

[0121] The acquisition unit 301 is further used to acquire a signal set, wherein the signal set includes at least one pair of ultrasonic transceiver signals, wherein the pair of ultrasonic transceiver signals includes an ultrasonic signal and an ultrasonic echo signal, wherein the ultrasonic echo signal may be a signal returned to the ultrasonic sensor after the ultrasonic signal reaches the secondary screen;

[0122] A detection unit 303, configured to detect whether there is an obstruction in the screen area of ​​the main screen according to the signal set;

[0123] The control unit 302 is further configured to control the main screen to perform a screen off operation if the main screen exists.

[0124] In the process of detecting whether there is an obstruction in the screen area of ​​the main screen according to the signal set, the detection unit 303 is further used to: determine a first distance according to the first ultrasonic transceiver signal; determine a second distance according to the second ultrasonic transceiver signal; calculate the difference between the first distance and the second distance; and detect whether there is an obstruction in the screen area of ​​the main screen according to the difference.

[0125] In one embodiment, the detection unit 303 is further used to: if the difference is within a first preset range, determine that there is an obstruction in the screen area of ​​the main screen; if the difference is not within the first preset range, determine that there is no obstruction in the screen area of ​​the main screen.

[0126] In one embodiment, before determining that there is an obstruction in the screen area of ​​the main screen, the control unit 302 is further used to: obtain the environment image taken by the camera; extract the contour area based on the environment image; determine whether the contour area matches the contour of the secondary screen; if so, determine that there is an obstruction in the screen area of ​​the main screen.

[0127] In one embodiment, the control unit 302 is further configured to:

[0128] Determine whether the first light intensity is less than or equal to a first preset light threshold, or whether the first light intensity is greater than or equal to a second preset light threshold; if so, determine that the light intensity meets a preset occlusion trigger condition.

[0129] In one embodiment, in controlling the main screen to perform a screen off operation, the control unit 302 is further used to: generate a screen off notification; and send the screen off notification to the main screen so that the main screen enters a screen off state according to the screen off notification.

[0130] In one embodiment, if present, before controlling the main screen to perform the screen off operation, the control unit 302 is further configured to:

[0131] Acquire a second light intensity detected by the ambient light sensor;

[0132] If the difference between the first light intensity and the second light intensity is within a second preset range, the main screen is controlled to perform a screen off operation.

[0133] This solution detects the current ambient light intensity of the blackboard's main screen and makes a preliminary occlusion judgment. After the ambient light intensity reaches the requirement, it starts the secondary occlusion judgment, that is, it uses ultrasonic detection to determine whether the secondary screen is blocked in the main screen area. If the ultrasonic detection also determines that the current secondary screen is blocking the main screen, a screen off notification is sent. That is, through two occlusion detections, it can accurately determine whether the current main screen needs to be turned off, thereby improving the accuracy of the screen off and avoiding the occurrence of accidental screen off.

[0134] See also Figure 4 , Figure 4 is a schematic diagram of the structure of a computer device provided in an embodiment of the present application, and the computer device may be a display. Figure 4 As shown, the computer device 40 includes a processor 401 and a memory 402. The memory 402 is connected to the processor 401, for example, via a bus.

[0135] The processor 401 is configured to support the computer device 40 to perform the corresponding functions in the method in the above method embodiment. The processor 401 can be a central processing unit (CPU), a network processor (NP), a hardware chip or any combination thereof. The above hardware chip can be an application specific integrated circuit (ASIC), a programmable logic device (PLD) or a combination thereof. The above PLD can be a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), a generic array logic (GAL) or any combination thereof.

[0136] Specifically, the processor 401 may include a sending card, a receiving card and a driving chip.

[0137] The memory 402 is used to store program codes, etc. The memory 402 may include a volatile memory (VM), such as a random access memory (RAM); the memory 402 may also include a non-volatile memory (NVM), such as a read-only memory (ROM), a flash memory, a hard disk drive (HDD) or a solid-state drive (SSD); the memory 402 may also include a combination of the above-mentioned types of memories.

[0138] The processor 401 may call the program code to perform the following operations:

[0139] Acquire a first light intensity of a surrounding environment detected by the ambient light sensor;

[0140] If the first light intensity meets the preset occlusion trigger condition, the ultrasonic sensor is controlled to emit an ultrasonic signal, and the ultrasonic signal returns to the ultrasonic sensor after reaching the secondary screen;

[0141] Acquire a signal set, the signal set including at least one pair of ultrasonic transceiver signals, the pair of ultrasonic transceiver signals including an ultrasonic signal and an ultrasonic echo signal, the ultrasonic echo signal may be a signal returned to the ultrasonic sensor after the ultrasonic signal reaches the secondary screen;

[0142] Detecting whether there is an obstruction in the screen area of ​​the main screen according to the signal set;

[0143] If it exists, control the main screen to perform the screen off operation.

[0144] An embodiment of the present application further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, wherein the computer program includes program instructions, and when the program instructions are executed by a computer, the computer executes the method described in the above embodiment.

[0145] A person skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium, and when the program is executed, it can include the processes of the embodiments of the above-mentioned methods. The storage medium can be a disk, an optical disk, a read-only memory (ROM) or a random access memory (RAM), etc.

[0146] The above disclosure is only the preferred embodiment of the present application, which certainly cannot be used to limit the scope of rights of the present application. Therefore, equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims

1. A screen-off control method, applied to a main screen of a blackboard, wherein the blackboard also includes a secondary screen, and the secondary screen can be moved relative to the main screen, characterized in that: The main screen is provided with an ambient light sensor and an ultrasonic sensor, and the method comprises: Acquire a first light intensity of a surrounding environment detected by the ambient light sensor; If the first light intensity meets the preset occlusion trigger condition, the ultrasonic sensor is controlled to emit an ultrasonic signal, and the ultrasonic signal returns to the ultrasonic sensor after reaching the secondary screen; Acquire a signal set, the signal set including at least one pair of ultrasonic transceiver signals, the pair of ultrasonic transceiver signals including an ultrasonic signal and an ultrasonic echo signal, the ultrasonic echo signal may be a signal returned to the ultrasonic sensor after the ultrasonic signal reaches the secondary screen; Detecting whether there is an obstruction in the screen area of ​​the main screen according to the signal set; If it exists, control the main screen to perform the screen off operation.

2. The screen off control method according to claim 1, characterized in that: The signal set includes a first ultrasonic transceiver signal and a second ultrasonic transceiver signal, and detecting whether there is an obstruction in the screen area of ​​the main screen according to the signal set includes: determining a first distance according to the first ultrasonic transceiver signal; determining a second distance according to the second ultrasonic transceiver signal; calculating a difference between the first distance and the second distance; Whether there is an obstruction in the screen area of ​​the main screen is detected according to the difference.

3. The screen off control method according to claim 2, characterized in that: Also includes: If the difference is within a first preset range, it is determined that there is an obstruction in the screen area of ​​the main screen; If the difference is not within the first preset range, it is determined that there is no obstruction in the screen area of ​​the main screen.

4. The screen off control method according to claim 3, characterized in that: The blackboard includes a camera, and the camera is arranged in the main screen. Before determining whether there is an obstruction in the screen area of ​​the main screen, the screen off control method further includes: Acquire an environment image captured by the camera; Extracting a contour area according to the environment image; Determining whether the outline area matches the outline of the secondary screen; If they match, it is determined that there is an obstruction in the screen area of ​​the main screen.

5. The screen off control method according to claim 1, characterized in that: Also includes: Determining whether the first light intensity is less than or equal to a first preset light threshold, or whether the first light intensity is greater than or equal to a second preset light threshold; If so, it is determined that the light intensity meets the preset shading trigger condition.

6. The screen off control method according to any one of claims 1 to 5, characterized in that: The controlling the main screen to perform the screen off operation includes: Generate a screen-off notification; The screen-off notification is sent to the main screen, so that the main screen enters the screen-off state according to the screen-off notification.

7. The method according to claim 1 or 6, characterized in that: If present, before controlling the main screen to perform a screen-off operation, the method further includes: Acquire a second light intensity detected by the ambient light sensor; If the difference between the first light intensity and the second light intensity is within a second preset range, the main screen is controlled to perform a screen off operation.

8. A screen off control device, characterized in that: A main screen applied to a blackboard, the blackboard further comprising a secondary screen, the secondary screen being movable relative to the main screen, characterized in that the main screen is provided with an ambient light sensor and an ultrasonic sensor, the method comprising: An acquisition unit, used for acquiring a first light intensity of a surrounding environment detected by the ambient light sensor; A control unit, used for controlling the ultrasonic sensor to transmit an ultrasonic signal, wherein the ultrasonic signal reaches the secondary screen and then returns to the ultrasonic sensor; The acquisition unit is further used to acquire a signal set, wherein the signal set includes at least one pair of ultrasonic transceiver signals, wherein the pair of ultrasonic transceiver signals includes an ultrasonic signal and an ultrasonic echo signal, wherein the ultrasonic echo signal may be a signal returned to the ultrasonic sensor after the ultrasonic signal reaches the secondary screen; A detection unit, configured to detect whether there is an obstruction in the screen area of ​​the main screen according to the signal set; The control unit is also used to control the main screen to perform a screen off operation if it exists.

9. A main screen, characterized in that: include: Display module; An ambient light sensor, disposed on the display module, for detecting a first light intensity of a surrounding environment; An ultrasonic sensor, disposed on the display module, for transmitting an ultrasonic signal; Memory; A processor is respectively connected to the display module, the ambient light sensor and the memory, and the processor is used to execute one or more computer programs stored in the memory. When the processor executes the one or more computer programs, the computer device implements the method described in any one of claims 1 to 7.

10. A blackboard, characterized in that: include: The main screen as claimed in claim 9; The secondary screen can be moved relative to the primary screen.

11. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, wherein the computer program includes program instructions, and when the program instructions are executed by a processor, the processor is caused to perform the method according to any one of claims 1 to 7.

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