Video processing method and device and vehicle

Abstract

The invention discloses a video processing method and device and a vehicle, and relates to the technical field of automobiles. According to the method, the inter-frame distance between every two adjacent frames of images in multiple frames of images included in a to-be-processed video input by a camera in each second is determined, the inter-frame distance represents the difference between the two adjacent frames of images, and then a distance threshold value is determined according to the inter-frame distance; according to the embodiment of the invention, the image with the inter-frame distance smaller than or equal to the distance threshold value from the previous frame image in the multi-frame image is removed from the first frame of the multi-frame image, namely, the image with small difference from the previous frame image is removed, so that the image frame number of the video per second is reduced on the basis of not influencing the continuity and authenticity of the video image; and then the controller processes part or all of the residual multiple frames of images into the video to be displayed, so that the data volume of the video processed by the controller is smaller.

Description

Technical Field

[0001] The present invention relates to the field of automobile technology, and in particular to a video processing method, device and vehicle. Background Art

[0002] Vehicles are generally equipped with multiple cameras, which can be used for panoramic monitoring systems, driving recorders, and electronic rearview mirrors. The video captured by the camera needs to be processed by the vehicle controller. Currently, the controller processes all the raw videos from the camera and sends them to the display screen for display. The controller processes a large amount of video data and occupies a lot of hardware resources. Summary of the invention

[0003] The present invention solves the technical problem of how to reduce the amount of video data processed by a vehicle-mounted controller by providing a video processing method, a device and a vehicle.

[0004] On the one hand, the present invention provides the following technical solutions:

[0005] A video processing method, comprising:

[0006] Receive the video to be processed from the camera input;

[0007] Determine the inter-frame distance between each two adjacent frames of images in the multiple frames of images contained in the to-be-processed video per second, wherein the inter-frame distance represents the difference between the two adjacent frames of images;

[0008] Determine a distance threshold according to the inter-frame distance, wherein the distance threshold is less than the maximum inter-frame distance and greater than the minimum inter-frame distance;

[0009] Starting from the first frame of the multiple frames of images, remove the images whose inter-frame distance with the previous frame of image is less than or equal to the distance threshold in the multiple frames of images;

[0010] Part or all of the remaining multiple frames of images are processed into a video to be displayed.

[0011] Optionally, determining the inter-frame distance between each two adjacent frames of images in the multiple frames of images contained in the video to be processed per second includes:

[0012] Obtaining each pixel value of each frame of the two adjacent frames of images;

[0013] The inter-frame distance is determined according to each of the pixel values.

[0014] Optionally, determining the inter-frame distance according to each pixel value includes:

[0015] According to the formula Calculate the inter-frame distance, where D is the inter-frame distance, i is the pixel value sequence number of a single frame image, n is the total number of pixels in a single frame image, and t is the frame sequence number of the image. is the i-th pixel value of the t-th frame image, is the i-th pixel value of the t+1-th frame image.

[0016] Optionally, determining a distance threshold according to the inter-frame distance includes:

[0017] An average value of the maximum inter-frame distance and the minimum inter-frame distance is calculated to obtain the distance threshold.

[0018] Optionally, processing part or all of the remaining multiple frames of images into a video to be displayed includes:

[0019] Determining the number of remaining frames of the plurality of image frames;

[0020] If the number of frames is lower than a preset threshold, all of the remaining multiple frames of images are processed as the video to be displayed;

[0021] If the number of frames is higher than the preset threshold, the first k frames of the remaining multiple frames of images are processed as the video to be displayed, where k is the preset threshold.

[0022] Optionally, the receiving of the video to be processed input by the camera includes:

[0023] The videos to be processed are received respectively from the front camera, rear camera, left camera and right camera of the vehicle; the front camera is used to shoot the front view of the vehicle, the rear camera is used to shoot the rear view of the vehicle, the left camera is used to shoot the left rear view of the vehicle, and the right camera is used to shoot the right rear view of the vehicle.

[0024] Optionally, the receiving of the video to be processed input by the camera includes:

[0025] The videos to be processed are received respectively from the left camera and the right camera of the vehicle; the left camera is used to shoot the left rear field of view of the vehicle, and the right camera is used to shoot the right rear field of view of the vehicle.

[0026] On the other hand, the present invention also provides the following technical solutions:

[0027] A video processing device, comprising:

[0028] A receiving module, used for receiving the video to be processed input by the camera;

[0029] A determination module, used to determine the inter-frame distance between each two adjacent frames of images in the multiple frames of images contained in the video to be processed per second, wherein the inter-frame distance represents the difference between the two adjacent frames of images;

[0030] and for determining a distance threshold according to the inter-frame distance, wherein the distance threshold is less than the maximum inter-frame distance and greater than the minimum inter-frame distance;

[0031] A removing module, used for removing, starting from the first frame of the multiple frames of images, images whose inter-frame distance with the previous frame of images is less than or equal to the distance threshold value;

[0032] The processing module is used to process part or all of the remaining multiple frames of images into a video to be displayed.

[0033] On the other hand, the present invention also provides the following technical solutions:

[0034] A vehicle comprises a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of any video processing method.

[0035] On the other hand, the present invention also provides the following technical solutions:

[0036] A computer-readable storage medium stores a computer program, which implements the steps of any video processing method when executed by a processor.

[0037] One or more technical solutions provided by the present invention have at least the following technical effects or advantages:

[0038] The present invention first determines the inter-frame distance between each two adjacent frames of images in the multiple frames of images contained in each second of a video to be processed input by a camera, the inter-frame distance characterizing the difference between the two adjacent frames of images, and then determines a distance threshold according to the inter-frame distance, and removes images in the multiple frames of images starting from the first frame of the multiple frames of images whose inter-frame distance with the previous frame of images is less than or equal to the distance threshold, that is, removes images with a small difference with the previous frame of images, and reduces the number of image frames per second of video without affecting the continuity and authenticity of the video picture, and then processes part or all of the remaining multiple frames of images into videos to be displayed, so that the amount of video data processed by the controller is smaller. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are 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 work.

[0040] Figure 1 A schematic diagram of a vehicle-mounted video display system according to an embodiment of the present invention;

[0041] Figure 2 is a flow chart of a video processing method according to an embodiment of the present invention;

[0042] Figure 3 FIG. 4 is a schematic diagram of a video processing device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0043] The embodiments of the present invention solve the technical problem of how to reduce the amount of video data processed by a vehicle-mounted controller by providing a video processing method, a device and a vehicle.

[0044] In order to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0045] like Figure 1 As shown, the vehicle video display system of the embodiment of the present invention includes 4 cameras (front camera, rear camera, left camera, right camera), 1 controller, 1 central control screen, 1 electronic interior rearview mirror display screen, 1 left electronic exterior rearview mirror display screen and 1 right electronic exterior rearview mirror display screen. Among them, the front camera is installed on the front bumper of the vehicle to shoot the front view of the vehicle; the rear camera is installed on the tailgate of the vehicle to shoot the rear view of the vehicle; the left camera is installed at the left rearview mirror of the vehicle to shoot the left rear view of the vehicle; the right camera is installed at the right rearview mirror of the vehicle to shoot the right rear view of the vehicle; the controller is used to fuse the videos input by the front camera, the rear camera, the left camera and the right camera and send them to the central control screen (at this time, the central control screen is equivalent to the display screen of the vehicle-mounted panoramic monitoring system or the display screen of the driving recorder, realizing the panoramic monitoring function or the driving recording function) for display, process the video input by the rear camera and send it to the electronic interior rearview mirror display screen for display, process the video input by the left camera and send it to the left electronic exterior rearview mirror display screen for display, and process the video input by the right camera and send it to the right electronic exterior rearview mirror display screen for display. The vehicle-mounted video display system of the embodiment of the present invention only needs four cameras to realize the panoramic monitoring function, the driving recording function, the electronic interior rearview mirror function and the electronic exterior rearview mirror function, with high integration and low cost.

[0046] like Figure 2 As shown, the embodiment of the present invention can be applied to Figure 1 The video processing method of the controller includes:

[0047] Step S1, receiving a video to be processed input by a camera;

[0048] Step S2, determining the inter-frame distance between each two adjacent frames of images in the multiple frames of images contained in each second of the video to be processed, where the inter-frame distance represents the difference between the two adjacent frames of images;

[0049] Step S3, determining a distance threshold according to the inter-frame distance, wherein the distance threshold is smaller than the maximum inter-frame distance and larger than the minimum inter-frame distance;

[0050] Step S4, starting from the first frame of the multi-frame image, remove the image whose inter-frame distance with the previous frame image is less than or equal to the distance threshold in the multi-frame image;

[0051] Step S5: Process part or all of the remaining multiple frames of images into a video to be displayed.

[0052] In step S1, the camera is not limited to the vehicle-mounted camera, but can also be a camera in other fields, such as a home surveillance camera, a road surveillance camera. Taking the vehicle-mounted camera as an example, the camera can be any one of the front camera, the rear camera, the left camera, and the right camera, and steps S1-S5 can be performed on the video input by the front camera, the rear camera, the left camera, and the right camera. The field of view angle of the vehicle-mounted camera can be ≥ (H: 195°V: 152°), the resolution can be ≥1920*1080, the frame rate can be 60fps, the dynamic range can be ≥140dB, the signal-to-noise ratio can be ≥45dB, the operating temperature can be -40~85℃, and the protection level can be IP69.

[0053] Taking into account that the electronic interior rearview mirror function and the electronic exterior rearview mirror function have high requirements for video picture smoothness, while the panoramic monitoring function does not have high requirements for video picture smoothness, when the vehicle realizes the panoramic monitoring function, steps S1-S5 can be performed on the videos input by the front camera, rear camera, left camera, and right camera respectively. At this time, step S1 includes: receiving the videos to be processed input by the front camera, rear camera, left camera, and right camera respectively.

[0054] Taking into account that the driving recording function has high requirements for the smoothness of the video images in front and behind the vehicle, and does not have high requirements for the smoothness of the video images behind the left and right of the vehicle, when the vehicle realizes the driving recording function, steps S1-S5 can be performed on the videos input by the left camera and the right camera respectively. At this time, step S1 includes: receiving the videos to be processed input by the left camera and the right camera respectively.

[0055] In step S2, if the frame rate of the camera is 60fps, then each second of the video to be processed contains 60 frames of images, and step S2 needs to determine the inter-frame distance between each two adjacent frames of the 60 frames. The inter-frame distance represents the difference between two adjacent frames of images. A large inter-frame distance represents a large difference between two adjacent frames of images, that is, the difference between the two real pictures represented by the two frames of images is large; a small inter-frame distance represents a small difference between two adjacent frames of images, that is, the difference between the two real pictures represented by the two frames of images is small. It can be understood that if one of the two frames of images with small differences in the video is removed, it will basically not affect the continuity and authenticity of the video picture, and the number of frames of the image can also be reduced, so as to achieve the purpose of reducing the amount of video data processed by the controller; and for two frames of images with large differences in the video, due to their large differences, removing one of the frames will reduce the continuity and authenticity of the video picture, so it is not recommended to remove it.

[0056] Step S2 may specifically include: obtaining each pixel value of each frame of two adjacent frames of images; determining the inter-frame distance according to each pixel value. Among them, all pixel values ​​of each frame of images represent the color characteristics of the frame of images, and the inter-frame distance determined according to each pixel value of the image can represent the color characteristics of the image. Further, determining the inter-frame distance according to each pixel value may specifically include: according to the formula Calculate the inter-frame distance, where D is the inter-frame distance, i is the pixel value sequence number of a single frame image, n is the total number of pixels in a single frame image, and t is the frame sequence number of the image. is the i-th pixel value of the t-th frame image, is the i-th pixel value of the t+1-th frame image. It can be seen that the formula first calculates the square of the difference of the pixel values ​​at the same position of two adjacent frames, then calculates the sum of the square of the difference of the pixel values ​​at all positions, and finally calculates the square root of the sum of the square of the difference. This is equivalent to calculating the inter-frame distance of two adjacent frames according to the difference of the pixel values ​​at each position of the two adjacent frames. The inter-frame distance reflecting the difference in color characteristics of the two adjacent frames can be obtained. A large inter-frame distance means a large difference in the color characteristics of the two adjacent frames and a large difference in the two real pictures reflected by the two adjacent frames.

[0057] Step S3 may use the median or mode of all inter-frame distances as the distance threshold, or may include: calculating the average of the maximum inter-frame distance and the minimum inter-frame distance to obtain the distance threshold.

[0058] In step S4, the images whose inter-frame distance with the previous frame image is less than or equal to the distance threshold are removed from the multiple frames of image, that is, the images with small difference with the previous frame image are removed. Assuming that the first frame image of each second is retained by default, if the inter-frame distance between the second frame image and the first frame image is greater than the distance threshold, the second frame image is retained, that is, the first and second frames of image are retained; if the inter-frame distance between the third frame image and the second frame image is less than the distance threshold, the third frame image is removed, and the first and second frames of image are retained. At this time, the fourth frame image The previous frame of the image is the second frame; if the inter-frame distance between the fourth frame and the second frame is less than the distance threshold, the fourth frame is removed, and the first and second frames are retained. At this time, the previous frame of the fifth frame is also the second frame; if the inter-frame distance between the fifth frame and the second frame is greater than the distance threshold, the fifth frame is retained, that is, the first, second, and fifth frames are retained. At this time, the previous frame of the sixth frame is the fifth frame; and so on, after screening 60 frames of images per second. It can be seen that step S4 can reduce the number of image frames contained in each second of video, that is, reduce the frame rate, for example, the frame rate can be reduced from 60fps to 30fps.

[0059] In step S5, the remaining multiple frames of images can be directly processed into videos to be displayed. For example, if there are 40 frames of images left, all 40 frames of images are processed into videos to be displayed, and if there are 20 frames of images left, all 20 frames of images are processed into videos to be displayed. However, the amount of video data processed by the controller for the remaining 40 frames of images is still large. In order to further reduce the amount of video data processed by the controller, step S5 can also include: determining the number of frames of the remaining multiple frames of images; if the number of frames of the remaining multiple frames of images is lower than the preset threshold, all the remaining multiple frames of images are processed into videos to be displayed; if the number of frames of the remaining multiple frames of images is higher than the preset threshold, the first k frames of the remaining multiple frames of images are processed into videos to be displayed, k is the preset threshold. Considering that the highest frame rate that the human eye can capture is generally 30fps, that is, when the video frame rate is lower than 30fps, the human eye will feel stuck, so the preset threshold can be 30. In this way, if there are 40 frames of images left per second, the first 30 frames of the remaining 40 frames of images are processed into videos to be displayed, which can further reduce the amount of video data, and if the preset threshold is 30, the user will not feel that the picture is not smooth. After removing each second of the video to be processed, the remaining images of each second are processed into the video to be displayed for that second, and finally each second of the video to be displayed is merged into a complete and continuous video to be displayed.

[0060] As can be seen from the above, the video processing method of the embodiment of the present invention first determines the inter-frame distance between each two adjacent frames of images in the multiple frames of images contained in each second of the video to be processed input by the camera, the inter-frame distance characterizes the difference between the two adjacent frames of images, and then determines the distance threshold according to the inter-frame distance, and starts from the first frame of the multiple frames of images to remove the images whose inter-frame distance with the previous frame of images is less than or equal to the distance threshold, that is, remove the images with small differences from the previous frame of images, and reduce the number of image frames per second of video without affecting the continuity and authenticity of the video picture. The controller then processes part or all of the remaining multiple frames of images as videos to be displayed, so that the amount of video data processed by the controller is smaller.

[0061] like Figure 3 As shown, the embodiment of the present invention also provides a video processing device, including:

[0062] A receiving module, used for receiving the video to be processed input by the camera;

[0063] A determination module, used to determine the inter-frame distance between each two adjacent frames of images in the multiple frames of images contained in each second of the video to be processed, where the inter-frame distance represents the difference between the two adjacent frames of images;

[0064] and for determining a distance threshold according to the inter-frame distance, the distance threshold being less than the maximum inter-frame distance and greater than the minimum inter-frame distance;

[0065] A removal module is used to remove, starting from the first frame of the multiple frames of images, images whose inter-frame distance with the previous frame of images is less than or equal to a distance threshold in the multiple frames of images;

[0066] The processing module is used to process part or all of the remaining multiple frames of images into a video to be displayed.

[0067] Furthermore, the module can be specifically used for:

[0068] Obtain each pixel value of each frame of two adjacent frames of images;

[0069] The inter-frame distance is determined from each pixel value.

[0070] Furthermore, the determination module can also be specifically used for:

[0071] According to the formula Calculate the inter-frame distance, where D is the inter-frame distance, i is the pixel value sequence number of a single frame image, n is the total number of pixels in a single frame image, and t is the frame sequence number of the image. is the i-th pixel value of the t-th frame image, is the i-th pixel value of the t+1-th frame image.

[0072] Furthermore, the module can be specifically used for:

[0073] The average of the maximum inter-frame distance and the minimum inter-frame distance is calculated to obtain the distance threshold.

[0074] Furthermore, the processing module may be specifically used to: determine the number of frames of the remaining multiple frames of images;

[0075] If the number of frames is lower than a preset threshold, all the remaining multiple frames of images are processed as the video to be displayed;

[0076] If the number of frames is higher than a preset threshold, the first k frames of the remaining multiple frames are processed as the video to be displayed, where k is the preset threshold.

[0077] Furthermore, the receiving module can be specifically used for:

[0078] The video to be processed is received from the front camera, rear camera, left camera and right camera of the vehicle respectively; the front camera is used to shoot the front view of the vehicle, the rear camera is used to shoot the rear view of the vehicle, the left camera is used to shoot the left rear view of the vehicle, and the right camera is used to shoot the right rear view of the vehicle.

[0079] Furthermore, the receiving module can be specifically used for:

[0080] The video to be processed is received from the left camera and the right camera of the vehicle respectively; the left camera is used to shoot the left rear view of the vehicle, and the right camera is used to shoot the right rear view of the vehicle.

[0081] Based on the same inventive concept as the video processing method mentioned above, an embodiment of the present invention also provides a computer device (vehicle), including a memory, a processor and a computer program stored in the memory, and the processor executes the computer program to implement the steps of any one of the video processing methods mentioned above.

[0082] Since the computer device introduced in the embodiment of the present invention is a computer device used to implement the video processing method in the embodiment of the present invention, based on the video processing method introduced in the embodiment of the present invention, those skilled in the art can understand the specific implementation of the computer device in the embodiment of the present invention and its various variations, so how the computer device implements the method in the embodiment of the present invention is not described in detail here. As long as those skilled in the art implement the computer device used in the video processing method in the embodiment of the present invention, it belongs to the scope of protection of the present invention.

[0083] Based on the same inventive concept as the above-mentioned video processing method, the present invention also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of any of the above-mentioned video processing methods are implemented.

[0084] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0085] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 These computer program instructions can also be stored in a computer-readable memory that can guide a computer or other programmable data processing device to work in a specific way, so that the instructions stored in the computer-readable memory produce a product including an instruction device, which implements the functions specified in the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0086] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0087] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0088] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A video processing method, characterized in that: include: Receive the video to be processed from the camera input; Determine the inter-frame distance between each two adjacent frames of images in the multiple frames of images contained in the to-be-processed video per second, wherein the inter-frame distance represents the difference between the two adjacent frames of images; Determine a distance threshold according to the inter-frame distance, wherein the distance threshold is less than the maximum inter-frame distance and greater than the minimum inter-frame distance; Starting from the first frame of the multiple frames of images, remove the images whose inter-frame distance with the previous frame of image is less than or equal to the distance threshold in the multiple frames of images; Part or all of the remaining multiple frames of images are processed into a video to be displayed.

2. The video processing method according to claim 1, characterized in that: The step of determining the inter-frame distance between each two adjacent frames of images in the plurality of frames of images contained in the video to be processed per second includes: Obtaining each pixel value of each frame of the two adjacent frames of images; The inter-frame distance is determined according to each of the pixel values.

3. The video processing method according to claim 2, characterized in that: The determining the inter-frame distance according to each pixel value comprises: According to the formula Calculate the inter-frame distance, where D is the inter-frame distance, i is the pixel value sequence number of a single frame image, n is the total number of pixels in a single frame image, and t is the frame sequence number of the image. is the i-th pixel value of the t-th frame image, is the i-th pixel value of the t+1-th frame image.

4. The video processing method according to claim 1, characterized in that: The determining a distance threshold according to the inter-frame distance comprises: An average value of the maximum inter-frame distance and the minimum inter-frame distance is calculated to obtain the distance threshold.

5. The video processing method according to claim 1, characterized in that: The processing of part or all of the remaining multiple frames of images into a video to be displayed includes: Determining the number of remaining frames of the plurality of image frames; If the number of frames is lower than a preset threshold, all of the remaining multiple frames of images are processed as the video to be displayed; If the number of frames is higher than the preset threshold, the first k frames of the remaining multiple frames of images are processed as the video to be displayed, where k is the preset threshold.

6. The video processing method according to claim 1, characterized in that: The receiving of the video to be processed input by the camera includes: The videos to be processed are received respectively from the front camera, rear camera, left camera and right camera of the vehicle; the front camera is used to shoot the front view of the vehicle, the rear camera is used to shoot the rear view of the vehicle, the left camera is used to shoot the left rear view of the vehicle, and the right camera is used to shoot the right rear view of the vehicle.

7. The video processing method according to claim 1, characterized in that: The receiving of the video to be processed input by the camera includes: The videos to be processed are received respectively from the left camera and the right camera of the vehicle; the left camera is used to shoot the left rear field of view of the vehicle, and the right camera is used to shoot the right rear field of view of the vehicle.

8. A video processing device, characterized in that: include: A receiving module, used for receiving the video to be processed input by the camera; A determination module, used to determine the inter-frame distance between each two adjacent frames of images in the multiple frames of images contained in the video to be processed per second, wherein the inter-frame distance represents the difference between the two adjacent frames of images; and for determining a distance threshold according to the inter-frame distance, wherein the distance threshold is less than the maximum inter-frame distance and greater than the minimum inter-frame distance; A removing module, used for removing, starting from the first frame of the multiple frames of images, images whose inter-frame distance with the previous frame of images is less than or equal to the distance threshold value; The processing module is used to process part or all of the remaining multiple frames of images into a video to be displayed.

9. A vehicle, characterized in that: The invention comprises a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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