An adaptive light supplement method, system, device, and medium

Abstract

The application provides a self-adaptive light supplement method, system, device and medium, comprising: acquiring a depth image and a visible light image of a target object through an image acquisition device; acquiring a distance between a face region of the target object and the image acquisition device, denoted as a face distance, according to the depth image and the visible light image; determining an included angle between the current face and a center line of the light supplement lamp according to the face distance and erection parameters of the image acquisition device, and determining a real-time illuminance value of the face region according to the included angle; wherein the erection parameters comprise an erection height and an image acquisition angle of the image acquisition device; acquiring a light supplement adjustment coefficient corresponding to the included angle of the current face region according to a pre-determined optimal light supplement illuminance value of the face, and adjusting the real-time illuminance value to the optimal light supplement illuminance value according to the light supplement adjustment coefficient. The application can adaptively perform dynamic light supplement, and ensures light supplement precision.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of video monitoring, in particular to a self-adaptive light compensation method, system, device and medium. BACKGROUND

[0002] With the progress of society and the development of artificial intelligence technology, face recognition technology is widely used in various industries; in the video monitoring industry, cameras with face capture function are also more and more applied in the construction of safe city. In the face capture camera, the key to affect the face detection and recognition rate is the quality of the face photo. In the normal light scene, the camera can collect clear and appropriate brightness face pictures, and the intelligent algorithm detection and recognition rate is high; in the night low light scene, the control effect of the camera light compensation lamp is crucial, if the light compensation is too strong, the face area is overexposed, and the intelligent detection cannot detect the face feature points; if the light compensation is too weak, the face area is dark, and the face feature points cannot be detected, so a method for realizing self-adaptive face light compensation is particularly important.

[0003] The traditional light compensation method needs to judge whether there is a moving face in the picture, and after detecting the face, the light compensation lamp level is adjusted according to the exposure brightness of the face area. The image exposure brightness detection depends on the calculation accuracy of the image recognition algorithm, and the light compensation effect is poor. SUMMARY

[0004] In view of the problems existing in the prior art, the present application provides a self-adaptive light compensation method, system, device and medium, which mainly solves the problem of insufficient light compensation accuracy based on image exposure detection in the traditional method.

[0005] In order to achieve the above purpose and other purposes, the technical scheme adopted by the present application is as follows.

[0006] A self-adaptive light compensation method, comprising:

[0007] obtaining a depth image and a visible light image of a target object by an image acquisition device, and obtaining a distance between a face area of the target object and the image acquisition device as a face distance according to the depth image and the visible light image; wherein the image acquisition device comprises a depth image acquisition unit, a visible light image acquisition unit and a light compensation lamp;

[0008] determining an included angle between the current face and a center line of the light compensation lamp according to the face distance and erection parameters of the image acquisition device, and determining a real-time illuminance value of the face area according to the included angle; wherein the erection parameters include an erection height and an image acquisition angle of the image acquisition device;

[0009] According to the predetermined optimal light compensation illuminance value of the face, a light compensation adjustment coefficient corresponding to the included angle of the current face region is obtained, and the real-time illuminance value is adjusted to the optimal light compensation illuminance value according to the light compensation adjustment coefficient.

[0010] Optionally, before the depth image and the visible light image of the target object are acquired by the image acquisition device, the image acquisition angle of the depth image acquisition unit, the image acquisition angle of the visible light image acquisition unit, and the light compensation angle of the light compensation lamp are calibrated to the same angle.

[0011] Optionally, the distance between the face region of the target object and the image acquisition device is obtained according to the depth image and the visible light image, and is recorded as a face distance, comprising:

[0012] Coordinate information of the face region in the visible light image is obtained, and depth information of the face region is determined according to the depth image and the coordinate information; wherein the depth information comprises distances from each point of the face region to the image acquisition device;

[0013] The face distance is determined according to the depth information.

[0014] Optionally, the face distance is determined according to the depth information, comprising:

[0015] The mean value of the distances from each point of the face region to the image acquisition device is obtained as the face distance.

[0016] Optionally, according to the face distance and the erection parameter of the image acquisition device, an included angle between the current face and the center line of the light compensation lamp is determined, comprising:

[0017] The height of the human body is obtained, and the included angle between the current face and the center line of the light compensation lamp is determined according to the position relationship among the height of the human body, the face distance, and the erection parameter.

[0018] Optionally, the included angle between the current face and the center line of the light compensation lamp is represented as:

[0019]

[0020] wherein, is the included angle between the current face and the center line of the light compensation lamp; θ is the image acquisition angle of the image acquisition device; H is the erection height of the image acquisition device; S is the distance from the current face region to the image acquisition device.

[0021] Optionally, the real-time illuminance value of the face region is determined according to the included angle, comprising:

[0022] The spatial distribution of the light distribution curve of the light compensation lamp is obtained;

[0023] obtaining a corresponding relationship table of different angles deviating from the center line and corresponding angle illuminance values according to the spatial distribution;

[0024] obtaining a corresponding real-time illuminance value from the corresponding relationship table according to the included angle.

[0025] An adaptive light supplement system comprises:

[0026] A face distance detection module is configured to acquire a depth image and a visible light image of a target object through an image acquisition device, and obtain a distance between a face region of the target object and the image acquisition device as a face distance according to the depth image and the visible light image; the image acquisition device comprises a depth image acquisition unit, a visible light image acquisition unit and a light supplement lamp; wherein the image acquisition device comprises a depth image acquisition unit, a visible light image acquisition unit and a light supplement lamp;

[0027] An included angle acquisition module is configured to determine an included angle between a current face and a center line of the light supplement lamp according to the face distance and erection parameters of the image acquisition device, and determine a real-time illuminance value of the face region according to the included angle; wherein the erection parameters comprise an erection height and an image acquisition angle of the image acquisition device.

[0028] A light supplement adjustment module is configured to obtain a light supplement adjustment coefficient of a corresponding included angle of a current face region according to a pre-determined optimal light supplement illuminance value of a face, and adjust the real-time illuminance value to the optimal light supplement illuminance value according to the light supplement adjustment coefficient.

[0029] An apparatus comprises:

[0030] one or more processors; and

[0031] one or more machine-readable media having instructions stored thereon that, when executed by the one or more processors, cause the apparatus to perform the adaptive light supplement method.

[0032] A computer-readable storage medium having instructions stored thereon that, when executed by one or more processors, cause an apparatus to perform the adaptive light supplement method.

[0033] As described above, the adaptive light supplement method, system, apparatus and medium have the following beneficial effects.

[0034] The application combines a depth image and a visible light image to detect the distance of a face region to an image acquisition device, determines the angle between the face and a light compensation lamp according to the distance and image acquisition device assumed parameters, determines the real-time illumination value corresponding to the angle based on the characteristics of the light compensation lamp, and issues the real-time light compensation adjustment coefficient of the light compensation lamp to complete real-time dynamic adaptive light compensation of the light compensation lamp, which can effectively improve the light compensation accuracy. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 The figure is a flowchart of the adaptive light compensation method in an embodiment of the application.

[0036] Figure 2 The figure is a module diagram of the adaptive light compensation system in an embodiment of the application.

[0037] Figure 3 The figure is a structural diagram of the device in an embodiment of the application.

[0038] Figure 4 The figure is a schematic diagram of the relative position between the light compensation lamp and the human body in an embodiment of the application.

[0039] Figure 5 The figure is a spatial distribution diagram of the light distribution curve of the light compensation lamp in an embodiment of the application.

[0040] Figure 6 The figure is a flowchart of the adaptive light compensation method in another embodiment of the application. DETAILED DESCRIPTION

[0041] The embodiments of the present application will be described herein below with reference to specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in the specification. The present application can also be implemented or applied in different specific embodiments, and the details in the specification can be modified or changed based on different views and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0042] It should be noted that the diagrams provided in the following embodiments only schematically illustrate the basic concept of the present application, and the diagrams only show the components related to the present application, not the number, shape and size of the components during actual implementation. The shapes, number and proportions of the components during actual implementation can be arbitrarily changed, and the layout pattern of the components can be more complex.

[0043] Please refer to Figure 1 The present application provides an adaptive light compensation method, which comprises the following steps:

[0044] In step S01, a depth image and a visible light image of a target object are acquired by an image acquisition device, and a distance between a face region of the target object and the image acquisition device is obtained according to the depth image and the visible light image, and the distance is recorded as a face distance; the image acquisition device comprises a depth image acquisition unit, a visible light image acquisition unit and a fill light; wherein the image acquisition device comprises the depth image acquisition unit, the visible light image acquisition unit and the fill light;

[0045] In step S02, an included angle between a current face and a center line of the fill light is determined according to the face distance and an erection parameter of the image acquisition device, and a real-time illumination value of the face region is determined according to the included angle; wherein the erection parameter comprises an erection height and an image acquisition angle of the image acquisition device.

[0046] In step S03, a fill light adjustment coefficient corresponding to the included angle of the current face region is obtained according to a pre-determined optimal fill light illumination value of the face, and the real-time illumination value is adjusted to the optimal fill light illumination value according to the fill light adjustment coefficient.

[0047] In an embodiment, before the depth image and the visible light image of the target object are acquired by the image acquisition device, the image acquisition angle of the depth image acquisition unit, the image acquisition angle of the visible light image acquisition unit and the fill light angle of the fill light are calibrated to the same angle. Specifically, the depth image acquisition unit can adopt a depth camera, and the visible light image acquisition unit can adopt a conventional snapshot camera. Before image acquisition, the depth image acquisition unit, the visible light image acquisition unit and the fill light can be pre-registered so that the image acquisition angle and the fill light angle remain consistent. After the registration is completed, the depth image acquisition unit can output an IR image of the current target object, and the IR image contains the distance from each point of the target object to the image acquisition device, i.e. depth information. The visible light image acquisition unit can output a visible light image of the target object under the corresponding angle.

[0048] In an embodiment, the distance between the face region of the target object and the image acquisition device is obtained according to the depth image and the visible light image, and the distance is recorded as a face distance, comprising:

[0049] Coordinate information of the face region in the visible light image is acquired, and depth information of the face region is determined according to the depth image and the coordinate information; wherein the depth information comprises the distance from each point of the face region to the image acquisition device;

[0050] The face distance is determined according to the depth information.

[0051] In an embodiment, the face distance is determined according to the depth information, comprising:

[0052] An average of distances from each point in the face region to the image acquisition device is obtained as the face distance.

[0053] Specifically, after obtaining the visible light image, the face region of the target object in the visible light image can be obtained through an image detection algorithm. The image detection algorithm can use a pre-trained neural network classification framework such as a recurrent neural network or a deep learning neural network. The specific network architecture selection and training process can be adjusted according to actual application requirements, which is not limited here. After obtaining the face region, since the depth image and the visible light image have been registered before acquisition, the depth information of the corresponding face region can be directly obtained from the depth image according to the face region coordinates. The coordinate conversion process is a prior art and will not be repeated here. The depth information is the distance from each point in the face region to the depth image acquisition unit. Since the relative positions of the depth image acquisition unit, the visible light image acquisition unit, and the fill light are uniquely determined after the device installation is completed. According to the distance from each point in the face region to the depth image acquisition unit, the distance from each point in the face region to the fill light can be determined. In another embodiment, if the depth image acquisition unit, the visible light image acquisition unit, and the fill light are integrally arranged, the distance from each point in the face region to the depth image acquisition unit can be used as the distance from each point in the face region to the fill light. After determining the distance from each point in the face region to the fill light, the average of the distances from each point to the fill light can be calculated, and the average is used as the distance from the face region to the fill light, denoted as the face distance.

[0054] In an embodiment, according to the face distance and the installation parameters of the image acquisition device, the angle between the current face and the center line of the fill light is determined, including:

[0055] The height of the human body is obtained, and the angle between the current face and the center line of the fill light is determined according to the positional relationship among the height of the human body, the face distance, and the installation parameters.

[0056] In an embodiment, the height of the current target object can be detected by a sensor as the height of the human body. The height information of a predetermined number of personnel can also be collected, and the average of the height information is calculated as the height of the human body, and the statistical height of the human body is used as the height value of the current face.

[0057] In an embodiment, as shown in Figure 4 It is known that the depth camera, the visible light camera, and the fill light have the same angle, and the device installation height H and the device installation angle According to statistical data, the average height of a person is about h, and the angle between the current face and the center line of the fill light is represented as:

[0058]

[0059] wherein, is the included angle between the current face and the center line of the light compensation lamp; θ is the image acquisition angle of the image acquisition device; H is the erection height of the image acquisition device; S is the distance from the current face region to the image acquisition device.

[0060] In an embodiment, determining the real-time illumination value of the face region according to the included angle comprises:

[0061] acquiring the spatial distribution of the light distribution curve of the light compensation lamp;

[0062] acquiring, according to the spatial distribution, a corresponding relationship table of different angles deviating from the center line and corresponding angle illumination values;

[0063] acquiring the corresponding real-time illumination value from the corresponding relationship table according to the included angle.

[0064] Specifically, when the face is at the center of the light compensation lamp, the illumination value on the face in the environment at this time is , the output intensity of the light compensation lamp is , and according to the attenuation of light, the light intensity is inversely proportional to the square of the emission distance, so .

[0065] Please refer to Figure 5 , the light distribution curve of the light compensation lamp is spindle-shaped in space, and the light intensity gradually attenuates from the center of the optical axis to both sides.

[0066] After the design of each light compensation lamp is completed, the output light intensity and the three-dimensional space corresponding relationship table of the angle deviating from the center can be measured by a spatial distribution photometer and other instruments, which is expressed in a two-dimensional table as follows:

[0067]

[0068] The illumination value of the face at different positions can be obtained by looking up the table.

[0069] In an embodiment, the best light compensation illumination value of the face in the environment can be obtained by pre-test, and according to the test, when the best light compensation illumination value on the face in a low-illumination environment is , the face effect is best at this time, that is, if the face is in the best light compensation state, the best intensity output by the light compensation lamp is . By driving the light compensation lamp intensity through a simple judgment module, the light compensation lamp output light intensity is adaptively adjusted, so that the face can obtain the best light compensation effect at different positions, and finally output high-quality face pictures.

[0070] Please refer toFigure 6 In another embodiment, the adaptive light compensation method provided by the present application comprises the following steps:

[0071] (1) Face distance acquisition

[0072] The IR image can be output by the TOF module camera, and the color image can be output by the visible light camera. The face region coordinates in the image can be acquired by the visible light camera through the face detection algorithm. The depth distance of the face detected by the face detection algorithm can be acquired in real time by using the registered TOF module camera and visible light camera to perform coordinate conversion, i.e., the position distance of the face in the real-time image from the camera.

[0073] (2) Calculation of the angle between the face and the center of the light compensation lamp

[0074] The camera mounting height and the camera mounting depression angle data can be measured by device mounting survey. The distance of the face from the camera in the real-time image obtained in the foregoing step is used, the average height of the person is obtained through statistical data, and finally the angle value between the face region and the center of the light compensation lamp is calculated by using the trigonometric function.

[0075] (3) Calculation of the current illuminance of the face

[0076] The relationship between the emission intensity of the light compensation lamp and the distance is known according to the light attenuation law, the output intensity at different angles when deviating from the central optical axis of the light compensation lamp is obtained by looking up the space light distribution curve table of the light compensation lamp, and finally the real-time illuminance value of the face in the image at different angles from the central optical axis of the light compensation lamp is obtained.

[0077] (4) Issuing of the light compensation lamp adjustment coefficient

[0078] The optimal light compensation illuminance value on the face is obtained through actual light compensation test. The real-time calculated face illuminance value is multiplied by a certain light compensation lamp adjustment coefficient to dynamically adjust the light compensation lamp intensity, so as to achieve the optimal face light compensation illuminance.

[0079] Please refer to Figure 2 The embodiment provides an adaptive light compensation method system for executing the adaptive light compensation method described in the foregoing method embodiment. Since the technical principle of the system embodiment is similar to that of the foregoing method embodiment, the same technical details are not repeated.

[0080] In an embodiment, an adaptive light supplement system includes: a face distance detection module 10 configured to acquire a depth image and a visible light image of a target object by an image acquisition device, and acquire a distance between a face region of the target object and the image acquisition device as a face distance according to the depth image and the visible light image; the image acquisition device includes a depth image acquisition unit, a visible light image acquisition unit, and a light supplement lamp; wherein the image acquisition device includes a depth image acquisition unit, a visible light image acquisition unit, and a light supplement lamp; an included angle acquisition module 11 configured to determine an included angle between a current face and a center line of the light supplement lamp according to the face distance and erection parameters of the image acquisition device, and determine a real-time illumination value of the face region according to the included angle; wherein the erection parameters include an erection height and an image acquisition angle of the image acquisition device; and a light supplement adjustment module 12 configured to acquire a light supplement adjustment coefficient of the included angle corresponding to a current face region according to a pre-determined optimal light supplement illumination value of a face, and adjust the real-time illumination value to the optimal light supplement illumination value according to the light supplement adjustment coefficient.

[0081] Embodiments of the present application further provide an adaptive light supplement device, which can include: one or more processors; and one or more machine readable media having instructions stored thereon that, when executed by the one or more processors, cause the device to perform the method of embodiments of the present application. Figure 1 In actual applications, the device can be a terminal device or a server. Examples of the terminal device can include: a smart phone, a tablet computer, an e-book reader, an MP3 (Moving Picture Experts Group Audio Layer III) player, an MP4 (Moving Picture Experts Group Audio Layer IV) player, a laptop computer, an in-vehicle computer, a desktop computer, a set-top box, a smart television, a wearable device, and the like. Embodiments of the present application are not limited to specific devices.

[0082] Embodiments of the present application further provide a computer readable storage medium having one or more programs stored thereon, which, when applied to a device, can cause the device to perform the method of embodiments of the present application. Figure 1The instructions of the steps of the adaptive light compensation method. The machine readable medium can be any available medium that can be accessed by a computer or data storage device such as a server, data center, etc. that integrates one or more sets of available media. The available media can be a magnetic medium (such as a floppy disk, a hard disk, a magnetic tape), an optical medium (such as a DVD), or a semiconductor medium (such as a Solid State Disk (SSD)), etc.

[0083] Referring to Figure 3 The embodiment provides a device 80, which can be a desktop computer, a laptop computer, a smart phone, etc. In detail, the device 80 at least includes a memory 82 and a processor 83 connected through a bus 81, wherein the memory 82 is configured to store a computer program, and the processor 83 is configured to execute the computer program stored in the memory 82 to execute all or part of the steps in the foregoing method embodiments.

[0084] The system bus mentioned above can be a Peripheral Pomponent Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. The system bus can be divided into an address bus, a data bus, a control bus, etc. For the convenience of representation, only one thick line is used in the figure, but it does not mean that there is only one bus or only one type of bus. The communication interface is configured to realize the communication between the database access device and other devices (such as a client, a read-write library and a read-only library). The memory can include a Random Access Memory (RAM), and can also include a non-volatile memory such as at least one disk memory.

[0085] The processor mentioned above can be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; can also be a Digital Signal Processing (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA) or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component.

[0086] To sum up, the adaptive light supplement method, system, device and medium of the present application, through the depth camera registered with the visible light camera, the distance of the face is obtained in real time, and the relevant parameters are obtained through the device erection work survey, the angle between the face at different positions and the central optical axis of the light supplement lamp is calculated, and the light supplement illumination on the face is calculated through the optical related theory formula, finally through the simple driving control module, the purpose of adaptive adjustment of the light supplement lamp is achieved, the brightness of the light supplement lamp is dynamically adjusted for the face at different distances, and the photo quality of the captured face is improved; starting from the light supplement characteristics of the light supplement lamp itself, through the attenuation law of the light supplement lamp and the light distribution curve in space, the light supplement illumination on the real-time face is calculated, and the light intensity of the light supplement lamp is more accurately controlled. Therefore, the present application effectively overcomes the various shortcomings in the prior art and has high industrial utilization value.

[0087] The above embodiments only exemplarily illustrate the principles and effects of the present application, and are not used to limit the present application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes completed by those skilled in the art without departing from the spirit and technical thought disclosed by the present application should be covered by the claims of the present application.

Claims

1. An adaptive light compensation method, characterized in that, The method comprises the following steps: obtaining a depth image and a visible light image of a target object by an image acquisition device, and obtaining a distance between a face region of the target object and the image acquisition device as a face distance according to the depth image and the visible light image; wherein the image acquisition device comprises a depth image acquisition unit, a visible light image acquisition unit and a light supplement lamp; before obtaining the depth image and the visible light image of the target object by the image acquisition device, the method further comprises the following steps: calibrating an image acquisition angle of the depth image acquisition unit, an image acquisition angle of the visible light image acquisition unit and a light supplement angle of the light supplement lamp to the same angle; determining an included angle between a current face and a center line of the light supplement lamp according to the face distance and an erection parameter of the image acquisition device, and determining a real-time illuminance value of the face region according to the included angle; wherein the erection parameter comprises an erection height and an image acquisition angle of the image acquisition device; obtaining a light supplement adjustment coefficient corresponding to the included angle of the current face region according to a pre-determined optimal light supplement illuminance value of a face, and adjusting the real-time illuminance value to the optimal light supplement illuminance value according to the light supplement adjustment coefficient.

2. The adaptive light supplementing method of claim 1, wherein, The method for obtaining a distance between a face region of a target object and an image acquisition device as a face distance according to a depth image and a visible light image comprises the following steps: obtaining coordinate information of the face region in the visible light image, and determining depth information of the face region according to the depth image and the coordinate information; wherein the depth information comprises distances from each point of the face region to the image acquisition device; determining the face distance according to the depth information.

3. The adaptive light supplementing method of claim 2, wherein, The method for determining the face distance according to the depth information comprises the following steps: obtaining an average value of distances from each point of the face region to the image acquisition device as the face distance.

4. The adaptive light supplementing method of claim 1, wherein, The method for determining an included angle between a current face and a center line of a light supplement lamp according to the face distance and an erection parameter of an image acquisition device comprises the following steps: obtaining a body height, and determining the included angle between the current face and the center line of the light supplement lamp according to a positional relationship among the body height, the face distance and the erection parameter.

5. The adaptive light supplementing method of claim 4, wherein, The included angle between the current face and the center line of the light supplement lamp is expressed as: wherein, is an included angle between the current face and a center line of the light supplement lamp; θ is an image collection angle of the image collection device; H is an erection height of the image collection device; S is a distance from the current face region to the image collection device; and h is an average height of a person.

6. The adaptive light supplementing method of claim 1, wherein, The method for determining a real-time illuminance value of a face region according to the included angle comprises the following steps: obtaining a spatial distribution of a light distribution curve of the light supplement lamp; taking the center line of the light supplement lamp as a reference, obtaining a corresponding relationship table of different angles deviating from the center line and corresponding angle illuminance values according to the spatial distribution; and obtaining a corresponding real-time illuminance value from the corresponding relationship table according to the included angle.

7. An adaptive light supplement system, characterized in that The method comprises the following steps: The face distance detection module is configured to acquire a depth image and a visible light image of a target object through an image acquisition device, and acquire a distance between a face region of the target object and the image acquisition device as a face distance according to the depth image and the visible light image; the image acquisition device comprises a depth image acquisition unit, a visible light image acquisition unit and a fill light; wherein the image acquisition device comprises a depth image acquisition unit, a visible light image acquisition unit and a fill light; before acquiring the depth image and the visible light image of the target object through the image acquisition device, the method further comprises: calibrating an image acquisition angle of the depth image acquisition unit, an image acquisition angle of the visible light image acquisition unit and a fill light angle of the fill light to the same angle; The included angle acquisition module is configured to determine an included angle between the current face and a center line of the fill light according to the face distance and an erection parameter of the image acquisition device, and determine a real-time illuminance value of the face region according to the included angle; wherein the erection parameter comprises an erection height and an image acquisition angle of the image acquisition device; The fill light adjustment module is configured to acquire a fill light adjustment coefficient corresponding to the included angle of the current face region according to a pre-determined optimal fill light illuminance value of the face, and adjust the real-time illuminance value to the optimal fill light illuminance value according to the fill light adjustment coefficient.

8. An adaptive light supplementing electronic device, characterized by One or more processors; And One or more machine-readable media having instructions stored thereon that, when executed by one or more processors, cause the device to perform the method of any of claims 1-6. Instructions stored thereon that, when executed by one or more processors, cause the device to perform the method of any of claims 1-6.

9. A computer-readable storage medium, characterized in that, ​

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