A vehicle-mounted multi-eye height measurement method based on microwave and its application

Abstract

The present invention provides a vehicle-mounted multi-eye height measurement method based on microwaves and its application, which collects N slow-time observation data and generates corresponding slow-time images, wherein N is an integer greater than or equal to 2; registers the slow-time images to obtain registered images; performs target detection on the registered images to obtain the target to be measured and generate a corresponding distance change matrix; and estimates the height of the target to be measured based on the distance change matrix. Using multiple slow-time observation data, multi-eye observation of microwaves is realized, and the height of the target to be measured is estimated using the distance change matrix with high accuracy, thereby realizing the detection of small targets.

Description

Technical Field

[0001] The present invention relates to the field of intelligent transportation technology, and in particular to a microwave-based vehicle-mounted multi-visual height measurement method and application thereof. Background Art

[0002] In-vehicle multi-view imaging technology is a key component of autonomous driving and advanced driver assistance systems (ADAS). Currently, it mainly uses multiple optical cameras to achieve high-precision perception of the vehicle's surrounding environment. The multi-view system of optical cameras relies on the principle of stereo vision, that is, the distance of objects is calculated by analyzing the parallax between multiple images obtained by the camera. Computer vision algorithms such as SIFT, SURF, and stereo matching algorithms are used for feature extraction and matching to generate depth maps. The coordinated work of multiple cameras can improve the accuracy and robustness of depth information. Multi-view optical imaging systems provide key environmental information for autonomous vehicles, enabling them to perceive other vehicles, pedestrians, road signs and obstacles, and make path planning and real-time decisions. However, optical multi-view imaging has huge application scenario limitations. In low light or strong contrast conditions, the imaging effect may be limited. Weather conditions such as rain, snow, fog and haze may affect the performance of the camera, requiring more advanced image processing algorithms.

[0003] In addition to cameras, another sensor widely used in the field of in-vehicle autonomous driving is microwave radar. Compared with cameras, the advantage of microwave radar is that it can sense all day long, is insensitive to ambient light, and can work normally in bad weather such as rain, fog, and snow. In addition, microwave radar also has the advantage of a longer detection distance. However, due to the limitations of antenna size and hardware resources, the resolution of 4D microwave radar is usually low in the height (vertical) direction, and it cannot measure the precise height of objects, making it impossible to accurately detect and identify small objects in highly complex environments.

[0004] Therefore, there is an urgent need for a microwave-based vehicle-mounted multi-visual height measurement method and its application to improve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a microwave-based vehicle-mounted multi-eye height measurement method and its application, which can accurately measure the height of objects and realize the detection of small targets.

[0006] In a first aspect, the present invention provides a vehicle-mounted multi-eye height measurement method based on microwaves, comprising:

[0007] Collecting N slow-time observation data and generating corresponding slow-time images, where N is an integer greater than or equal to 2;

[0008] Registering the slow-time image to obtain a registered image;

[0009] Performing target detection on the registered image to obtain the target to be detected and generating a corresponding distance change matrix;

[0010] The height of the target to be measured is estimated based on the distance change matrix.

[0011] The method of the present invention has the following beneficial effects: by collecting N slow-time observation data and generating corresponding slow-time images, wherein N is an integer greater than or equal to 2; registering the slow-time images to obtain registered images; performing target detection on the registered images to obtain the target to be measured and generate a corresponding distance change matrix; estimating the height of the target to be measured based on the distance change matrix, realizing multi-eye observation of microwaves by using multiple slow-time observation data, and estimating the height of the target to be measured by using the distance change matrix with high accuracy, thereby realizing the detection of small targets.

[0012] Optionally, the observation data is collected by transceiver antennas arranged in a concentrated manner in the horizontal direction; and / or the value of N is greater than or equal to 100. The beneficial effect is that by concentrating the transceiver antenna resources in the horizontal direction, the limited resources can be fully utilized, the horizontal angle resolution capability of the radar system can be improved, and clear azimuth information can be obtained during the imaging process. Setting the value of N to be greater than 100 can achieve the use of hundreds of slow-time observation results during vehicle driving, and the ability to resist occasional errors and random noise is much stronger than that of traditional vehicle-mounted radar systems, thereby making the height measurement more accurate.

[0013] Optionally, generating a corresponding slow-time image includes:

[0014] Signal compression in the distance dimension and the azimuth dimension is performed at each slow time to generate a high-resolution two-dimensional image.

[0015] Optionally, performing signal compression in the distance dimension and the azimuth dimension at each slow time to generate a high-resolution two-dimensional image includes:

[0016] The received echo signal is preprocessed, and the joint compression of the signals in the distance and azimuth dimensions is achieved through an algorithm, and the observed two-dimensional intensity distribution image is output.

[0017] Optionally, registering the slow-time image includes:

[0018] The image similarity algorithm is used to perform local registration on the slow-time image. By calculating the image similarity of adjacent time slices, the position change of the perspective change caused by the movement of the vehicle is corrected, so that the image maintains consistency and coherence in time sequence. Its beneficial effect is that by using the image similarity algorithm to perform local registration on the slow-time image, the matching of the observed targets at different slow times is achieved, the position change of the perspective change caused by the movement of the vehicle can be corrected, and the image maintains consistency and coherence in time sequence.

[0019] Optionally, performing target detection on the registered image includes:

[0020] For the registered image, using the CFAR method to perform target detection;

[0021] And / or generating a corresponding distance change matrix comprising:

[0022] For each target to be measured, its corresponding distance unit is extracted at different time points, and all time series data are summarized to generate a corresponding distance change matrix. Its beneficial effect is that for each target to be measured, its corresponding distance unit is extracted at different time points, and all time series data are summarized to generate a corresponding distance change matrix, which is helpful to analyze its dynamic characteristics in space.

[0023] Optionally, estimating the height of the target to be measured based on the distance change matrix includes:

[0024] The difference in the distance change rate of the target to be measured at different heights is analyzed, and the distance change matrix extracted from the multi-time series data is used to estimate the height of the target to be measured through model calculation and rate comparison. The beneficial effect is that the target height can be accurately estimated through model calculation and rate comparison, and the multi-time series can improve the robustness of the data and reduce false detections caused by noise or radar system errors.

[0025] In a second aspect, the present invention provides a microwave-based vehicle-mounted multi-eye height measurement device, which includes modules / units for executing any possible design method of the first aspect. These modules / units can be implemented by hardware, or by hardware executing corresponding software implementations.

[0026] In a third aspect, the present invention provides an electronic device, comprising a memory and a processor, wherein the memory stores a program that can be run on the processor, and when the program is executed by the processor, the electronic device implements a method for executing any possible design of any of the above aspects.

[0027] In a fourth aspect, the present invention provides a readable storage medium, wherein the readable storage medium stores a program, and when the program is executed, it implements any possible design method of any of the above aspects.

[0028] In a fifth aspect, the present invention provides a computer program product, comprising a computer program, which implements the above method when executed by a processor.

[0029] For the beneficial effects of the second to fifth aspects, reference may be made to the description of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic flow chart of a microwave-based vehicle-mounted multi-eye height measurement method provided in an embodiment of the present invention;

[0031] Figure 2 A schematic structural diagram of a microwave-based vehicle-mounted multi-eye height measurement device provided in an embodiment of the present invention;

[0032] Figure 3 A schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with general skills in the field to which the present invention belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0034] In view of the problem that the current vehicle-mounted height measurement accuracy is poor and the correction cannot accurately detect and identify small objects, the microwave-based vehicle-mounted multi-eye height measurement method provided by the present invention uses multiple slow-time observation data and a distance change matrix to estimate the height of the target to be measured, thereby realizing high-precision microwave multi-eye height measurement, and then realizing the detection of small targets. The technical scheme in the embodiment of the present invention is described below in conjunction with the drawings in the embodiment of the present invention. Among them, in the description of the embodiment of the present invention, the terms used in the following embodiments are only for the purpose of describing specific embodiments, and are not intended to be used as limitations on the present invention. The singular expressions "a", "said", "above", "the" and "this" are intended to also include expressions such as "one or more", unless there is a clear indication to the contrary in the context. It should also be understood that in the following embodiments of the present invention, "at least one", "one or more" refers to one or more than two (including two). The term "and / or" is used to describe the association relationship of associated objects, indicating that three relationships can exist; for example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0035] References to "one embodiment" or "some embodiments" described in this specification mean that one or more embodiments of the present invention include specific features, structures or characteristics described in conjunction with the embodiment. Thus, the statements "in one embodiment", "in some embodiments", "in some other embodiments", and "in some other embodiments" that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways. The term "connected" includes direct and indirect connections, unless otherwise stated. "First" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated.

[0036] In the embodiments of the present invention, "exemplarily" or "for example" is used to indicate an example, illustration or description. Any embodiment or design described as "exemplarily" or "for example" in the embodiments of the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of "exemplarily" or "for example" is intended to present the relevant concepts in a specific way.

[0037] like Figure 1 As shown, the present invention provides a vehicle-mounted multi-eye height measurement method based on microwaves, comprising:

[0038] S101, collecting N slow-time observation data and generating corresponding slow-time images, wherein N is an integer greater than or equal to 2.

[0039] In some embodiments, in order to make full use of limited resources, improve the horizontal angular resolution capability of the radar system, and ensure that clear azimuth information can be obtained during the imaging process, the observation data is collected by transceiver antennas centrally arranged in the horizontal direction.

[0040] In other embodiments, in order to utilize hundreds of slow-time observations during vehicle travel and to have a much stronger ability to combat occasional errors and random noise than traditional vehicle-mounted radar systems, thereby making height measurement more accurate, the value of N is greater than or equal to 100.

[0041] In some further embodiments, generating the corresponding slow-time image includes: performing signal compression in the distance dimension and the azimuth dimension at each slow time to generate a high-resolution two-dimensional image.

[0042] In some specific embodiments, performing signal compression in the distance dimension and the azimuth dimension at each slow time to generate a high-resolution two-dimensional image includes: preprocessing the received echo signal, achieving joint compression of the signals in the distance and azimuth dimensions through an algorithm, and outputting an observed two-dimensional intensity distribution image.

[0043] S102, registering the slow-time image to obtain a registered image.

[0044] In some embodiments, in order to achieve matching of observed targets at different slow time instants, correct the position changes of perspective changes caused by vehicle movement, and keep the image consistent and coherent in time sequence, the slow time image is registered, including: locally registering the slow time image using an image similarity algorithm, and correcting the position changes of perspective changes caused by vehicle movement by calculating the image similarity of adjacent time slices, so that the image remains consistent and coherent in time sequence.

[0045] S103, performing target detection on the registered image to obtain a target to be detected and generating a corresponding distance change matrix.

[0046] In some embodiments, performing target detection on the registered image includes: performing target detection on the registered image using a CFAR method.

[0047] In other embodiments, in order to analyze its dynamic characteristics in space, generating a corresponding distance change matrix includes: for each target to be measured, extracting its corresponding distance unit at different time points, and aggregating all time series data to generate a corresponding distance change matrix.

[0048] S104: Estimate the height of the target to be measured based on the distance change matrix.

[0049] In some embodiments, in order to achieve accurate estimation of the target height, multiple time series can improve the robustness of the data and reduce false detections caused by noise or radar system errors. Estimating the height of the target to be measured based on the distance change matrix includes: analyzing the differences in the distance change rates of the target to be measured at different heights, and using the distance change matrix extracted from the multi-time series data to estimate the height of the target to be measured through model calculation and rate comparison.

[0050] For ease of understanding, this embodiment further describes the specific implementation process of the above method in combination with a specific application scenario system, which specifically includes the following steps:

[0051] Step a, centralized resource configuration: In order to improve the resolution in azimuth, the limited transceiver antenna resources are centralized in the horizontal direction to collect observation data. This antenna configuration can make full use of limited resources, improve the horizontal angle resolution capability of the radar system, and ensure that clear azimuth information can be obtained during the imaging process.

[0052] Step b, slow time image generation: During the vehicle's movement, the signal compression in the distance dimension and the azimuth dimension is performed at each slow time to generate a high-resolution two-dimensional image. This process includes preprocessing the received echo signal, realizing the joint compression of the distance and azimuth dimensions through an algorithm, and outputting the observed two-dimensional intensity distribution image.

[0053] Step c, local image registration: In order to achieve the alignment of data at multiple observation times in time sequence, the generated two-dimensional images are locally registered using an image similarity algorithm. By calculating the image similarity of adjacent time slices, the position change caused by the perspective change caused by vehicle movement can be corrected, so that the image remains consistent and coherent in time sequence.

[0054] Step d, distance change matrix generation: For the registered image, use the CFAR method to detect the target. For each detected target, extract its corresponding distance unit at different time points. Collect these time series data to generate the distance change matrix of the target. This matrix records the distance information of the target at different slow times, which helps to analyze its dynamic characteristics in space.

[0055] Step e, height measurement: high-precision height measurement is achieved by analyzing the difference in the distance change rate of the target to be measured at different heights. The distance change rate of the target at different time series is closely related to its height. By using the distance change matrix extracted from the multi-time series data, through model calculation and rate comparison, the target height can be accurately estimated. At the same time, multi-time series can improve the robustness of the data and reduce false detections caused by noise or radar system errors.

[0056] The advantage of the embodiment of the present invention is that, compared with optical multi-view high-precision perception based on multiple cameras, the system has the following advantages:

[0057] 1. Microwaves are insensitive to ambient light and are more resistant to extreme weather conditions such as rain, snow, haze, and smoke, and can work around the clock.

[0058] 2. Microwave detection has a longer range, allowing the on-board ADAS system to obtain environmental information earlier and make path planning.

[0059] Compared with the traditional 4D microwave radar, the present invention has the following advantages:

[0060] 1. Limited by the size of the vehicle-mounted microwave radar, the height resolution of the traditional radar is low and cannot effectively detect small targets. However, the height measurement accuracy of the target of the present invention is much higher than that of the traditional radar, and can actually reach the centimeter level. Thus, the detection of small targets can be achieved.

[0061] 2. Traditional vehicle-mounted radars are limited by antenna resources, and the antenna resources distributed in pitch and elevation are relatively tight. Due to the insufficient number of antennas, the actual measurement is greatly affected by system errors and noise, resulting in a decrease in height measurement accuracy. However, the present invention can utilize hundreds of slow-time observation results during vehicle driving, and its ability to resist occasional errors and random noise is much stronger than that of traditional vehicle-mounted radar systems, resulting in higher height measurement accuracy.

[0062] 3. Compared with traditional vehicle-mounted radar, the present invention can concentrate all antenna resources in the horizontal direction. Therefore, under the condition of the same antenna resources, its horizontal measurement accuracy and resolution will be higher than that of traditional vehicle-mounted radar.

[0063] like Figure 2As shown, based on the above-mentioned microwave-based vehicle-mounted multi-eye altitude measurement method, the present invention provides a microwave-based vehicle-mounted multi-eye altitude measurement device, including: an acquisition unit 201, used to acquire N slow-time observation data and generate corresponding slow-time images, wherein N is an integer greater than or equal to 2; a registration unit 202, used to register the slow-time images to obtain the registered images; a detection unit 203, used to perform target detection on the registered images, obtain the target to be measured and generate a corresponding distance change matrix; a calculation unit 204, used to estimate the height of the target to be measured based on the distance change matrix.

[0064] It should be understood that all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module, which will not be repeated here. In addition, the use of suffixes such as "module", "component" or "unit" used to represent elements is only for the purpose of facilitating the description of the present invention, and has no specific meaning in itself. Therefore, "module", "component" or "unit" can be used in a mixed manner. The terminal can be implemented in various forms. For example, the terminal described in the present invention may include mobile terminals such as mobile phones, tablet computers, laptops, PDAs, portable media players (PMP), navigation devices, wearable devices, smart bracelets, pedometers, and fixed terminals such as digital TVs and desktop computers. The subsequent description will be described by taking the mobile terminal as an example, and those skilled in the art will understand that, in addition to components specifically used for mobile purposes, the construction according to the embodiment of the present invention can also be applied to fixed types of terminals.

[0065] In some other embodiments of the present invention, an electronic device 300 is disclosed. Figure 3 As shown, it may include: one or more processors 301; memory 302; display 303; one or more applications (not shown); and one or more computer programs 304. The above-mentioned components may be connected via one or more communication buses 305. The one or more computer programs 304 are stored in the above-mentioned memory 302 and configured to be executed by the one or more processors 301. The one or more computer programs 304 include instructions, which may be used to execute the following instructions: Figure 1 The various steps in the corresponding embodiments.

[0066] The processor 301 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc.

[0067] The memory 302 may be an internal storage unit of the electronic device 300, such as a hard disk or memory of the electronic device 300. The memory 302 may also be an external storage device of the electronic device 300, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card (FlashCard), etc. equipped on the electronic device 300. Further, the memory 302 may also include both an internal storage unit of the electronic device 300 and an external storage device. The memory 302 is used to store computer programs and other programs and data required by the electronic device. The memory 302 may also be used to temporarily store data that has been output or is to be output.

[0068] The computer program 304 may be divided into one or more modules / units. The one or more modules / units may be a series of computer program instruction segments capable of performing specific functions. The instruction segments are used to describe the execution process of the computer program 304 in the electronic device 300 .

[0069] In addition to the above structure, those skilled in the art can understand that Figure 3 It is only an example of the electronic device 300 and does not constitute a limitation of the electronic device 300. The electronic device 300 may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the electronic device may also include input and output devices, network access devices, buses, etc.

[0070] Those skilled in the art can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated into a processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of the present invention. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0071] Based on the above embodiments, the present invention further discloses a computer-readable storage medium having at least one computer program stored thereon, and when the computer program is executed by a processor, the microwave-based vehicle-mounted multi-visual height measurement method in the above embodiments is implemented.

[0072] A person of ordinary skill in the art can understand that all or part of the steps in the method for implementing the above embodiment can be completed by instructing a processor through a program, and the program can be stored in a computer-readable storage medium, and the storage medium is a non-transitory medium, such as a random access memory, a read-only memory, a flash memory, a hard disk, a solid-state hard disk, a magnetic tape, a floppy disk, an optical disc, and any combination thereof. The above storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or a data center that includes one or more available media. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a digital video disc (DVD)), or a semiconductor medium (e.g., a solid-state disk (SSD)), etc.

[0073] The descriptions of the processes or structures corresponding to the above-mentioned figures have different emphases. For parts that are not described in detail in a certain process or structure, please refer to the relevant descriptions of other processes or structures.

[0074] In summary, the microwave-based vehicle-mounted multi-eye height measurement method and its application disclosed in the present invention utilize multiple slow-time observation data to realize multi-eye observation of microwaves, and utilize the distance change matrix to estimate the height of the target to be measured with high accuracy, thereby realizing the detection of small targets.

[0075] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A microwave-based vehicle-mounted multi-eye height measurement method, characterized in that: include: Collecting N slow-time observation data and generating corresponding slow-time images, where N is an integer greater than or equal to 2; Registering the slow-time image to obtain a registered image; Performing target detection on the registered image to obtain the target to be detected and generating a corresponding distance change matrix; estimating the height of the target to be measured based on the distance change matrix; Estimating the height of the target to be measured based on the distance change matrix includes: The differences in the distance change rates of the target to be measured at different heights are analyzed, and the height of the target to be measured is estimated by using the distance change matrix extracted from the multi-time series data through model calculation and rate comparison.

2. The method according to claim 1, characterized in that The observation data is collected by transceiver antennas centrally arranged in the horizontal direction; and / or the value of N is greater than or equal to 100.

3. The method according to claim 1, characterized in that Generating the corresponding slow-time image includes: Signal compression in the distance dimension and the azimuth dimension is performed at each slow time to generate a high-resolution two-dimensional image.

4. The method according to claim 3, characterized in that Signal compression in the distance and azimuth dimensions is performed at each slow time to generate high-resolution two-dimensional images including: The received echo signal is preprocessed, and the joint compression of the signals in the distance and azimuth dimensions is achieved through an algorithm, and the observed two-dimensional intensity distribution image is output.

5. The method according to claim 1, characterized in that Registering the slow-time image includes: The slow-time images are locally registered using an image similarity algorithm, and the position change of the viewing angle caused by the movement of the vehicle is corrected by calculating the image similarity of adjacent time slices, so that the images maintain consistency and coherence in time sequence.

6. The method according to claim 1, characterized in that Performing target detection on the registered image includes: For the registered image, using the CFAR method to perform target detection; And / or generating a corresponding distance change matrix comprising: For each target to be measured, its corresponding distance unit is extracted at different time points, and all time series data are summarized to generate the corresponding distance change matrix.

7. A microwave-based vehicle-mounted multi-eye height measurement device, used in the method according to any one of claims 1 to 6, characterized in that: include: An acquisition unit, used for acquiring N slow-time observation data and generating corresponding slow-time images, wherein N is an integer greater than or equal to 2; A registration unit, used for registering the slow-time image to obtain a registered image; A detection unit, used to perform target detection on the registered image, obtain the target to be detected and generate a corresponding distance change matrix; A calculation unit, used for estimating the height of the target to be measured based on the distance change matrix; Estimating the height of the target to be measured based on the distance change matrix includes: The differences in the distance change rates of the target to be measured at different heights are analyzed, and the height of the target to be measured is estimated by using the distance change matrix extracted from the multi-time series data through model calculation and rate comparison.

8. An electronic device, characterized in that: The electronic device comprises a memory and a processor, wherein the memory stores a program executable on the processor, and when the program is executed by the processor, the electronic device implements the method according to any one of claims 1 to 6.

9. A readable storage medium, wherein a program is stored in the readable storage medium, characterized in that: When the program is executed, the method according to any one of claims 1 to 6 is implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

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