A pursuit terminal visibility measurement method and system

Abstract

This invention relates to a tracking-type terminal visibility measurement method and system. Based on the movement of two mobile terminals along a target movement path, and using mutual recognition between the two mobile terminals based on image capture actions as the judgment criterion, a cyclical interchange strategy is designed for the two mobile terminals to exchange positions with each other. This obtains the positions of each visibility change node, thereby accurately determining the visibility values ​​of each low-visibility segment, each non-low-visibility segment, and each detection position within each low-visibility segment on the target movement path. This achieves continuous, high-precision, and fully automatic measurement of low-visibility weather on roads, greatly reducing the danger of manual patrols and the cost of high-density deployment of visibility meters. It is particularly effective for localized dense fog (patch fog) that often occurs on roads at night. In addition, the design method can freely adjust the spacing between mobile terminals according to different regional traffic control standards, adapting to multiple industry scenarios and possessing broad market application prospects and economic value.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of pursuit terminal visibility measurement method and system, belong to visibility detection technical field. BACKGROUND

[0002] With the continuous increase of national highway mileage, road driving safety is also more and more concerned, especially the disastrous weather caused by heavy fog brings huge security risks to road safety. Early detection and finding out the low visibility section and accurately measuring the visibility value become the focus of meteorological, traffic and traffic management departments. The commonly used methods for monitoring visibility mainly include two kinds, one is to identify based on backscattering visibility meter, but due to the high cost of installation and maintenance of visibility meter, it is difficult to install and deploy in high density, so the monitoring ability of local fog on road is limited. The other is a visibility recognition method based on road video image, which mainly collects video images along the road through machine learning to realize automatic recognition of image visibility, but this method requires high environmental brightness, and it is difficult to accurately identify at night without enough light source. With the continuous maturity of unmanned aerial vehicle technology, the mobile and flexible advantages of unmanned aerial vehicle can help identify visibility at night. SUMMARY

[0003] The technical problem to be solved by the present application is to provide a pursuit terminal visibility measurement method, based on the movement of two mobile terminals along the target moving path, to design control analysis strategy, which can accurately determine the visibility value of each low visibility section, each non-low visibility section and each detection position in each low visibility section on the target moving path.

[0004] The present application adopts the following technical solutions to solve the above technical problems: the present application designs a pursuit terminal visibility measurement method, based on two mobile terminals each equipped with a sign device and an image capture device, according to the following steps A to step H, to realize the visibility detection of the target moving path and obtain the visibility value of each low visibility section, each non-low visibility section and each detection position in each low visibility section in the target moving path.

[0005] Step A. Based on the visibility value division threshold of the preset low visibility value and the non-low visibility value, the positions of the two mobile terminals on the non-low visibility section of the target moving path and at a distance of the visibility value division threshold from each other are taken as the initial positions of the two mobile terminals, and step B is entered.

[0006] Step B. Control both mobile terminals to move at a preset speed along one direction of the target moving path, and at the same time, the image capture device on the rear mobile terminal shoots to obtain a video stream directed to the direction of the sign device on the front mobile terminal in real time, and step C is entered.

[0007] Step C. In real time, determine whether the current video frame in the video stream obtained by the image capture device on the rear mobile terminal contains the marker device on the front mobile terminal. If yes, return to step B; otherwise, control both mobile terminals to stop moving. Record the position of the front mobile terminal corresponding to the previous moment as the boundary position of a low-visibility segment on the target movement path, and then proceed to step D.

[0008] Step D. Keep the position of the front mobile terminal stationary, control the rear mobile terminal to move along the target moving path towards the front mobile terminal at a preset speed and overtake the front mobile terminal, while updating the positions of the front and rear mobile terminals, and proceed to step E.

[0009] Step E. Keeping the rear mobile terminal stationary and the front mobile terminal moving, the image capture device on the rear mobile terminal captures a video stream pointing in the direction of the marker device on the front mobile terminal in real time, and then proceeds to step F;

[0010] Step F. In real time, determine whether the current video frame in the video stream obtained by the image capture device on the rear mobile terminal contains the marker device on the front mobile terminal. If yes, return to step E; otherwise, control the front mobile terminal to stop moving. The position of the front mobile terminal at the previous moment is the farthest visibility of the adjacent stationary position of the rear mobile terminal. Record the distance of the farthest visibility, which is the visibility value of the stationary position of the rear mobile terminal in the low visibility segment on the target moving path. Use it as the visibility value of a detection position in the low visibility segment on the target moving path, and then proceed to step G.

[0011] Step G. Determine whether the visibility value obtained in the adjacent step F is greater than or equal to the visibility value division threshold. If yes, it means that the mobile terminal in front has moved out of the low visibility segment on the target movement path. Record the position of the mobile terminal behind as the boundary position of the low visibility segment on the target movement path, and then proceed to step H; otherwise, return to step D.

[0012] Step H. Control the rear mobile terminal to move along the target movement path towards the forward mobile terminal to a position at a distance from the visibility value threshold, and then return to step B.

[0013] As a preferred technical solution of the present invention: in step C, if the current video frame in the video stream obtained by the image capture device on the rear mobile terminal does not include the marking device on the front mobile terminal, then the following step Ci is executed;

[0014] Step Ci. The image capture device on the front mobile terminal captures a video frame pointing in the direction of the marker device on the rear mobile terminal, and determines whether the video frame contains the marker device on the rear mobile terminal. If yes, proceed to step C-ii; otherwise, control both mobile terminals to stop moving, record the position of the front mobile terminal at the previous moment as the boundary position of a low visibility segment on the target movement path, and then proceed to step D.

[0015] Step C-ii. Control the image capture device on the rear mobile terminal to perform a self-test, and then the image capture device on the rear mobile terminal captures a video frame pointing in the direction of the marker device on the front mobile terminal, and determines whether the video frame contains the marker device on the front mobile terminal. If yes, return to step B; otherwise, determine that the image capture device on the rear mobile terminal is faulty and end the visibility detection of the target movement path.

[0016] In step F, if the current video frame in the video stream obtained by the image capture device on the rear mobile terminal does not contain the marking device on the front mobile terminal, then step Fi is executed.

[0017] Step Fi. The image capture device on the front mobile terminal captures a video frame pointing in the direction of the marker device on the rear mobile terminal, and determines whether the video frame contains the marker device on the rear mobile terminal. If yes, proceed to step F-ii; otherwise, control the front mobile terminal to stop moving. The position of the front mobile terminal at the previous moment is the farthest visibility of the stationary position of its adjacent rear mobile terminal. Record the distance of the farthest visibility, which is the visibility value of the stationary position of the rear mobile terminal in the low visibility segment of the target moving path. Use this as the visibility value of a detection position in the low visibility segment of the target moving path, and then proceed to step G.

[0018] Step F-ii. Control the image capture device on the rear mobile terminal to perform a self-test, and then the image capture device on the rear mobile terminal captures a video frame pointing in the direction of the marker device on the front mobile terminal, and determines whether the video frame contains the marker device on the front mobile terminal. If yes, return to step E; otherwise, determine that the image capture device on the rear mobile terminal is faulty and end the visibility detection of the target movement path.

[0019] As a preferred technical solution of the present invention: the marking devices mounted on the two mobile terminals are both light sources, and the two light sources have the same flashing period, the two mobile terminals have the same exposure period of the image capturing device, and the light source flashing period S1 is an integer multiple of the image capturing device exposure period S2, or the image capturing device exposure period S2 is an integer multiple of the light source flashing period S1.

[0020] As a preferred technical solution of the present invention: in steps C and F, it is determined in real time whether the current video frame in the video stream obtained by the image capture device on the rear mobile terminal contains the marker device on the front mobile terminal; in steps Ci and Fi, it is determined whether the obtained video frame contains the marker device on the rear mobile terminal; and in steps C-ii and F-ii, it is determined whether the obtained video frame contains the marker device on the front mobile terminal. The target tracking algorithm is executed on the determined marker device to realize the corresponding judgment in each step.

[0021] As a preferred technical solution of the present invention, the target tracking algorithm includes MobileNets-SSD as the preferred target tracking algorithm, and Bossting method, random learning or deep learning as alternative target tracking algorithms.

[0022] As a preferred technical solution of the present invention: both mobile terminals are drones, and the two drones are positioned at a preset height above the target movement path according to steps A to H to achieve visibility detection of the target movement path.

[0023] Corresponding to the above, the present invention also designs a system for implementing a tracking terminal visibility measurement method, including a control module that communicates with two mobile terminals respectively. The control module includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

[0024] The tracking-type terminal visibility measurement method and system described in this invention, compared with the prior art, has the following technical advantages:

[0025] This invention presents a tracking-type terminal visibility measurement method and system. Based on the movement of two mobile terminals along a target path, and using mutual recognition between the two mobile terminals based on image capture actions as the judgment criterion, a cyclical interchange strategy is designed for the two mobile terminals to exchange positions with each other. This obtains the positions of each visibility change node, thereby accurately determining the visibility values ​​of each low-visibility segment, each non-low-visibility segment, and each detection position within each low-visibility segment on the target path. This achieves continuous, high-precision, and fully automatic measurement of low-visibility weather on roads, greatly reducing the danger of manual patrols and the cost of high-density deployment of visibility meters. It is particularly effective for localized dense fog (patch fog) that often occurs on roads at night. In addition, the design method can freely adjust the spacing between mobile terminals according to different regional traffic control standards, making it adaptable to various industry scenarios such as highways, airports, and waterways, and has broad market application prospects and economic value. Attached Figure Description

[0026] Figure 1 This is a schematic diagram illustrating the initial application of the tracking-type terminal visibility measurement method designed in this invention;

[0027] Figure 2 This is a schematic diagram illustrating the application of the tracking-type terminal visibility measurement method designed in this invention.

[0028] Figure 3 This is a flowchart of the tracking-type terminal visibility measurement method designed in this invention. Detailed Implementation

[0029] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0030] This invention designs a tracking-type terminal visibility measurement method, such as... Figure 1 As shown, based on two mobile terminals, each equipped with a marking device and an image capture device, according to Figure 3 As shown, steps A to H are performed to detect the visibility of the target movement path and obtain the visibility values ​​of each low-visibility segment, each non-low-visibility segment, and each detection location in each low-visibility segment of the target movement path.

[0031] Step A. Figure 1 As shown, based on the preset visibility value and non-low visibility value classification threshold, the initial position of the two mobile terminals is taken as the position of the two mobile terminals on the non-low visibility segment of the target movement path and the distance between them from the visibility value classification threshold, and then proceeds to step B.

[0032] Step B. As Figure 2 As shown, both mobile terminals are controlled to move at a preset speed V along one direction of the target moving path. At the same time, the image capture device on the rear mobile terminal captures a video stream pointing in the direction of the marker device on the front mobile terminal in real time, and then proceeds to step C.

[0033] Step C. Execute MobileNets-SSD as the preferred target tracking algorithm, with Bossing method, random learning, or deep learning as alternatives. In real time, determine whether the current video frame in the video stream obtained by the image capture device on the rear mobile terminal contains the marker device on the front mobile terminal. If yes, return to step B; otherwise, proceed to step Ci.

[0034] Step Ci. The image capture device on the front mobile terminal captures a video frame pointing in the direction of the marker device on the rear mobile terminal. The MobileNets-SSD algorithm is selected as the primary target tracking algorithm, with Bossing, random learning, or deep learning as alternatives. The algorithm determines whether the video frame contains the marker device on the rear mobile terminal. If yes, proceed to step C-ii; otherwise, control both mobile terminals to stop moving. Record the position of the front mobile terminal at the previous moment as the boundary position of a low-visibility segment on the target's movement path, and then proceed to step D.

[0035] Step C-ii. Control the image capture device on the rear mobile terminal to perform a self-test, such as a self-test to check for faults in the image capture device itself, and to adjust the focus of its image capture; then, the image capture device on the rear mobile terminal captures a video frame pointing in the direction of the marker device on the front mobile terminal, and executes any target tracking algorithm, such as the Bossting method, random learning, or deep learning, to determine whether the video frame contains the marker device on the front mobile terminal. If yes, return to step B; otherwise, determine that the image capture device on the rear mobile terminal is faulty, and end the visibility detection of the target movement path.

[0036] Step D. As Figure 2 As shown, keep the position of the front mobile terminal stationary, control the rear mobile terminal to move along the target moving path towards the front mobile terminal at a preset speed V and pass the front mobile terminal, while updating the positions of the front and rear mobile terminals, and proceed to step E.

[0037] Step E. Figure 2 As shown, while keeping the rear mobile terminal stationary and the front mobile terminal moving, the image capture device on the rear mobile terminal captures a video stream pointing in the direction of the marker device on the front mobile terminal in real time, and then proceeds to step F.

[0038] Step F. Execute MobileNets-SSD as the preferred target tracking algorithm, with Bossting method, random learning, or deep learning as alternatives. In real time, determine whether the current video frame in the video stream obtained by the image capture device on the rear mobile terminal contains the marker device on the front mobile terminal. If yes, return to step E; otherwise, proceed to step Fi.

[0039] Step F1. A video frame pointing in the direction of the marker device on the rear mobile terminal is captured by the image capture device on the front mobile terminal. MobileNets-SSD is selected as the preferred target tracking algorithm, with Bossing method, random learning, or deep learning as alternatives. It is determined whether the video frame contains the marker device on the rear mobile terminal. If yes, proceed to step F-ii; otherwise, control the front mobile terminal to stop moving. The position of the front mobile terminal at the previous moment is the farthest visibility of the stationary position of its adjacent rear mobile terminal. The distance of the farthest visibility is recorded, which is the visibility value of the stationary position of the rear mobile terminal in the low visibility segment of the target movement path. This is used as the visibility value of a detection position in the low visibility segment of the target movement path, and then proceed to step G.

[0040] Step F-ii. Control the image capture device on the rear mobile terminal to perform a self-test, such as a self-test to check for faults in the image capture device itself, and to adjust the focus of its image capture; then, the image capture device on the rear mobile terminal captures a video frame pointing in the direction of the marker device on the front mobile terminal, and executes MobileNets-SSD as the preferred target tracking algorithm, with Bossting method, random learning, or deep learning as alternatives, to determine whether the video frame contains the marker device on the front mobile terminal. If yes, return to step E; otherwise, determine that the image capture device on the rear mobile terminal is faulty, and end the visibility detection of the target movement path.

[0041] Step G. Determine whether the visibility value obtained in the adjacent step F is greater than or equal to the visibility value division threshold. If yes, it means that the mobile terminal in front has moved out of the low visibility segment on the target movement path. Record the position of the mobile terminal behind as the boundary position of the low visibility segment on the target movement path, and then proceed to step H; otherwise, return to step D.

[0042] Step H. Figure 2 As shown, the control system moves the rear mobile terminal along the target movement path towards the forward mobile terminal to a position that is a distance from the visibility value threshold, and then returns to step B.

[0043] Applying the above-described tracking-type terminal visibility measurement method to practice, a threshold for distinguishing between low and non-low visibility values ​​is preset, such as 200m. The signage devices mounted on the two mobile terminals can be designed to use light sources. In the above design process, the flickering periods of the two light sources are the same, and the exposure periods of the image capture devices on the two mobile terminals are the same. The flickering period S1 of the light source is an integer multiple of the exposure period S2 of the image capture device, or the exposure period S2 of the image capture device is an integer multiple of the flickering period S1 of the light source. This design ensures that the image capture device on the rear mobile terminal can capture the light source on the front mobile terminal within the visible range, while also distinguishing the interference of other light sources on the light source on the front mobile terminal.

[0044] In practical applications, the target movement path applicable to the design of this invention can be a land road, a waterway, or a route at a specified altitude. For different types of movement paths, the mobile terminal selects different types of devices for application. For land roads, two mobile terminals can select two identical objects of any type, such as bicycles, motor vehicles, or pedestrians, and move along the land road path, and execute the above-mentioned design method to obtain the visibility values ​​of each low-visibility segment, each non-low-visibility segment, and each detection position in each low-visibility segment of the land road.

[0045] For waterways, two mobile terminals can select two identical objects from the same type of waterway mobile devices, move along the waterway path, and execute the above-mentioned design method to obtain the visibility values ​​of each low-visibility segment, each non-low-visibility segment, and each detection location in each low-visibility segment of the waterway.

[0046] In addition, for land roads, waterways, or routes at a specified altitude, the two mobile terminals can also select the same aircraft object of the same flight type, such as the same type of drone. The two drones are set at the same altitude above the land road, waterway, or route at a specified altitude, fly along the land road, waterway, or route at a specified altitude, and execute the above-mentioned design method to obtain the visibility values ​​of each low visibility segment, each non-low visibility segment, and each detection position in each low visibility segment of the land road, waterway, or route at a specified altitude.

[0047] In practical applications, this invention obtains the visibility values ​​of each low-visibility segment, each non-low-visibility segment, and each detection location within each low-visibility segment along the target movement path, thereby generating a corresponding low-visibility warning map for the path and providing safety alerts for the application of the corresponding actual path.

[0048] In practical applications, the above-mentioned chasing-type terminal visibility measurement method is further designed into a system for implementing this method, including a control module that communicates with two mobile terminals respectively. The control module includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the designed chasing-type terminal visibility measurement method.

[0049] This invention presents a tracking-type terminal visibility measurement method and system. Based on the movement of two mobile terminals along a target path, and using mutual recognition between the two mobile terminals based on image capture actions as the judgment criterion, a cyclical interchange strategy is designed for the two mobile terminals to exchange positions with each other. This obtains the positions of each visibility change node, thereby accurately determining the visibility values ​​of each low-visibility segment, each non-low-visibility segment, and each detection position within each low-visibility segment on the target path. This achieves continuous, high-precision, and fully automatic measurement of low-visibility weather on roads, greatly reducing the danger of manual patrols and the cost of high-density deployment of visibility meters. It is particularly effective for localized dense fog (patch fog) that often occurs on roads at night. In addition, the design method can freely adjust the spacing between mobile terminals according to different regional traffic control standards, making it adaptable to various industry scenarios such as highways, airports, and waterways, and has broad market application prospects and economic value.

[0050] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A method for measuring terminal visibility using a tracking method, characterized in that: Based on two mobile terminals, each equipped with a marker device and an image capture device, the visibility of the target movement path is detected according to steps A to H, and the visibility values ​​of each low-visibility segment, each non-low-visibility segment, and each detection position in each low-visibility segment are obtained in the target movement path. Step A. Based on the preset visibility value division threshold between low visibility and non-low visibility values, the initial positions of the two mobile terminals are taken as the positions of the two mobile terminals on the non-low visibility segment of the target movement path and at a distance of the visibility value division threshold from each other, and then proceed to Step B. Step B. Control both mobile terminals to move at a preset speed along one direction of the target moving path, while the image capture device on the rear mobile terminal captures a video stream pointing in the direction of the marker device on the front mobile terminal in real time, and then proceed to step C. Step C. In real time, determine whether the current video frame in the video stream obtained by the image capture device on the rear mobile terminal contains the marker device on the front mobile terminal. If yes, return to step B; otherwise, control both mobile terminals to stop moving. Record the position of the front mobile terminal corresponding to the previous moment as the boundary position of a low-visibility segment on the target movement path, and then proceed to step D. Step D. Keep the position of the front mobile terminal stationary, control the rear mobile terminal to move along the target moving path towards the front mobile terminal at a preset speed and overtake the front mobile terminal, while updating the positions of the front and rear mobile terminals, and proceed to step E. Step E. Keeping the rear mobile terminal stationary and the front mobile terminal moving, the image capture device on the rear mobile terminal captures a video stream pointing in the direction of the marker device on the front mobile terminal in real time, and then proceeds to step F; Step F. In real time, determine whether the current video frame in the video stream obtained by the image capture device on the rear mobile terminal contains the marker device on the front mobile terminal. If yes, return to step E; otherwise, control the front mobile terminal to stop moving. The position of the front mobile terminal at the previous moment is the farthest visibility of the adjacent stationary position of the rear mobile terminal. Record the distance of the farthest visibility, which is the visibility value of the stationary position of the rear mobile terminal in the low visibility segment on the target moving path. Use it as the visibility value of a detection position in the low visibility segment on the target moving path, and then proceed to step G. Step G. Determine whether the visibility value obtained in the adjacent step F is greater than or equal to the visibility value division threshold. If yes, it means that the mobile terminal in front has moved out of the low visibility segment on the target movement path. Record the position of the mobile terminal behind as the boundary position of the low visibility segment on the target movement path, and then proceed to step H; otherwise, return to step D. Step H. Control the rear mobile terminal to move along the target movement path towards the forward mobile terminal to a position at a distance from the visibility value threshold, and then return to step B.

2. The tracking-type terminal visibility measurement method according to claim 1, characterized in that: In step C, if the current video frame in the video stream obtained by the image capture device on the rear mobile terminal does not contain the marking device on the front mobile terminal, then the following step Ci is executed; Step Ci. The image capture device on the front mobile terminal captures a video frame pointing in the direction of the marker device on the rear mobile terminal, and determines whether the video frame contains the marker device on the rear mobile terminal. If yes, proceed to step C-ii; otherwise, control both mobile terminals to stop moving, record the position of the front mobile terminal at the previous moment as the boundary position of a low visibility segment on the target movement path, and then proceed to step D. Step C-ii. Control the image capture device on the rear mobile terminal to perform a self-test, and then the image capture device on the rear mobile terminal captures a video frame pointing in the direction of the marker device on the front mobile terminal, and determines whether the video frame contains the marker device on the front mobile terminal. If yes, return to step B; otherwise, determine that the image capture device on the rear mobile terminal is faulty and end the visibility detection of the target movement path. In step F, if the current video frame in the video stream obtained by the image capture device on the rear mobile terminal does not contain the marking device on the front mobile terminal, then step Fi is executed. Step Fi. The image capture device on the front mobile terminal captures a video frame pointing in the direction of the marker device on the rear mobile terminal, and determines whether the video frame contains the marker device on the rear mobile terminal. If yes, proceed to step F-ii; otherwise, control the front mobile terminal to stop moving. The position of the front mobile terminal at the previous moment is the farthest visibility of the stationary position of its adjacent rear mobile terminal. Record the distance of the farthest visibility, which is the visibility value of the stationary position of the rear mobile terminal in the low visibility segment of the target moving path. Use this as the visibility value of a detection position in the low visibility segment of the target moving path, and then proceed to step G. Step F-ii. Control the image capture device on the rear mobile terminal to perform a self-test, and then the image capture device on the rear mobile terminal captures a video frame pointing in the direction of the marker device on the front mobile terminal, and determines whether the video frame contains the marker device on the front mobile terminal. If yes, return to step E; otherwise, determine that the image capture device on the rear mobile terminal is faulty and end the visibility detection of the target movement path.

3. The chasing-type terminal visibility measurement method according to claim 1 or 2, characterized in that: The two mobile terminals are equipped with light sources, and the two light sources have the same flashing period. The two mobile terminals also have the same exposure period for the image capture devices. The light source flashing period S1 is an integer multiple of the image capture device exposure period S2, or the image capture device exposure period S2 is an integer multiple of the light source flashing period S1.

4. The chasing-type terminal visibility measurement method according to claim 1 or 2, characterized in that: In steps C and F, it is determined in real time whether the current video frame in the video stream obtained by the image capture device on the rear mobile terminal contains the marker device on the front mobile terminal. In steps Ci and Fi, it is determined whether the obtained video frame contains the marker device on the rear mobile terminal. In steps C-ii and F-ii, it is determined whether the obtained video frame contains the marker device on the front mobile terminal. The target tracking algorithm is executed on the determined marker device to realize the corresponding judgment in each step.

5. The chasing-type terminal visibility measurement method according to claim 4, characterized in that: The target tracking algorithms include MobileNets-SSD as the preferred target tracking algorithm, and Bossting method, random learning or deep learning as alternative target tracking algorithms.

6. The chasing-type terminal visibility measurement method according to claim 1 or 2, characterized in that: Both mobile terminals are drones. The two drones are positioned at a preset height above the target movement path and proceed through steps A to H to detect the visibility of the target movement path.

7. A system for implementing the tracking-type terminal visibility measurement method according to any one of claims 1 to 6, characterized in that: The method includes a control module that communicates with two mobile terminals respectively. The control module includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

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