Method, device and equipment for determining phase distribution of cardiopulmonary area signals

Abstract

The invention relates to a method, a device and equipment for determining phase distribution of heart and lung area signals. The method comprises the following steps of: acquiring a target electrical impedance tomography signal which is synchronous with mechanical movement of the heart of a testee in electrical impedance tomography signals of the chest of the testee at a plurality of detection moments; determining an electrical impedance static image of the chest of the testee according to the target electrical impedance tomography signal; respectively determining regions of interest of the heart and the lung of the testee in the electrical impedance static image; determining a peak pixel point image according to the electrical impedance time change curve corresponding to the target pixel point in the lung region of interest; and calculating the sum of pixel points in the heart region of interest and the lung region of interest, and multiplying the sum of the pixel points by each peak value pixel point in the peak value pixel point image one by one to obtain a phase distribution diagram of the heart and lung region signals of the tested person. Voltage signals synchronous with heart mechanical movement can correspond to spatial positions, so that phase distribution of blood flow signals in the heart and lung area of a tested person is accurately reflected.

Description

Technical Field

[0001] The present disclosure relates to the field of computer information processing technology, and in particular to a method, device and apparatus for determining phase distribution of cardiopulmonary regional signals. Background Art

[0002] Currently, radionuclide perfusion scanning can be used to measure pulmonary blood flow. However, radionuclide perfusion scanning uses radioactive isotope technetium, which is expensive to obtain and difficult to measure pulmonary perfusion in real time, let alone the phase distribution of pulmonary perfusion.

[0003] The existing electrical impedance tomography technology uses the following method to measure the phase of cardiac or pulmonary blood flow: first, extract the voltage signal synchronized with the mechanical movement of the heart from the original measured voltage signal, then average the channel dimension, and consider the average curve of the obtained time signal to be the curve that meets the phase characteristics of the cardiogenic signal;

[0004] The main disadvantages of the above method may include: on the one hand, the voltage signal synchronized with the mechanical movement of the heart is affected by the blood circulation of the heart and the lungs at the same time. Therefore, the average curve calculated from the voltage signal has no exact physical meaning and is difficult to correspond to the time nodes of heart contraction or relaxation; on the other hand, the voltage signal synchronized with the mechanical movement of the heart is difficult to correspond to the spatial position, so it is difficult to reflect the phase distribution of the blood flow signal in the heart and lung regions. Summary of the invention

[0005] The present disclosure provides a method, device and equipment for determining the phase distribution of cardiopulmonary regional signals to solve the problem in the above-mentioned background technology that the voltage signal synchronized with the mechanical movement of the heart is difficult to correspond to the spatial position, and therefore difficult to reflect the phase distribution of the heart regional blood flow signal.

[0006] In a first aspect, the present disclosure provides a method for determining phase distribution of cardiopulmonary regional signals, comprising:

[0007] Collecting a target electrical impedance tomography signal synchronized with the cardiac mechanical movement of the subject from among the electrical impedance tomography signals of the subject's chest at multiple detection moments;

[0008] Determining an electrical impedance static image of the chest of the subject according to the target electrical impedance tomography signal at each detection moment;

[0009] Determining the heart region of interest and the lung region of interest of the subject in the electrical impedance static image respectively;

[0010] Determine a peak pixel point image according to an electrical impedance time variation curve corresponding to a target pixel point in the lung region of interest;

[0011] The sum of the pixels in the heart region of interest and the lung region of interest is calculated, and the sum of the pixels is multiplied by each peak pixel in the peak pixel image one by one to obtain a phase distribution diagram of the heart and lung region signal of the subject.

[0012] In some embodiments, collecting a target electrical impedance tomography signal synchronized with the cardiac mechanical motion of the subject from among the electrical impedance tomography signals of the subject's chest at multiple detection moments includes:

[0013] After applying an excitation current or an excitation voltage to the body of the subject through some electrodes placed around the chest of the subject, data measurements are performed at multiple measurement moments on the remaining electrodes to obtain electrical signals; the electrical signals include current signals or voltage signals;

[0014] According to the mechanical movement frequency of the heart of the subject, the electrical signal is subjected to signal extraction processing to obtain a target electrical signal in the electrical signal that is synchronized with the mechanical movement of the heart of the subject.

[0015] In some embodiments, determining the static electrical impedance image of the chest of the subject according to the target electrical impedance tomography signal at each detection moment includes:

[0016] constructing an electrical impedance image sequence of the chest of the subject according to the target electrical impedance tomography signal at each detection moment;

[0017] Based on the electrical impedance image sequence, an electrical impedance static image of the subject's chest is integrated.

[0018] In some embodiments, constructing an electrical impedance image sequence of the chest of the subject according to the target electrical impedance tomography signal at each detection moment includes:

[0019] Calculate the difference between the target electrical signals measured at every two adjacent detection moments among all detection moments;

[0020] Calculating a differential reconstruction function of the difference to obtain a change in the electrical conductivity in the chest cavity of the subject at each of the two adjacent detection moments;

[0021] Determining the change in electrical impedance in the chest cavity of the subject at each of the two adjacent detection moments based on the change in electrical conductivity;

[0022] An electrical impedance image sequence of the chest of the subject is constructed according to the electrical impedance change.

[0023] In some embodiments, integrating the static electrical impedance image of the chest of the subject based on the electrical impedance image sequence includes:

[0024] Acquire an electrical impedance element matrix corresponding to the electrical impedance image sequence, wherein each row of the electrical impedance element matrix is ​​the electrical impedance of a target pixel point in the electrical impedance image sequence at a detection time;

[0025] Calculating the electrical impedance average value of all elements in the electrical impedance element matrix;

[0026] Determine the slope and intercept of each pixel in the electrical impedance image sequence according to the electrical impedance of each pixel at each detection moment and the electrical impedance average value;

[0027] The slopes of the pixels in the electrical impedance image sequence are combined to obtain a static electrical impedance image of the chest of the subject.

[0028] In some embodiments, determining a lung region of interest of the subject in the electrical impedance static image includes:

[0029] Determining the value of each pixel in the electrical impedance static image according to the slope of each pixel in the electrical impedance static image and a first preset threshold;

[0030] Determine the lung region of interest of the subject according to the values ​​of each pixel point;

[0031] Among them, if the slope of the target pixel point in the electrical impedance static image is greater than the first preset threshold, the value of the target pixel point is 1, otherwise, the value of the target pixel point is 0, and the area composed of pixels corresponding to the value of 1 is determined as the lung area of ​​interest of the subject.

[0032] In some embodiments, determining the cardiac region of interest of the subject in the electrical impedance static image includes:

[0033] Determine the value of each pixel in the electrical impedance static image according to the slope of each pixel in the electrical impedance static image and a second preset threshold;

[0034] Determine the cardiac region of interest of the subject according to the values ​​of each pixel point;

[0035] Among them, if the slope of the target pixel point in the electrical impedance static image is less than the second preset threshold, the value of the target pixel point is 1, otherwise, the value of the target pixel point is 0, and the area composed of pixels corresponding to the value of 1 is determined as the heart area of ​​interest of the subject.

[0036] In some embodiments, determining a peak pixel point image according to an electrical impedance time variation curve corresponding to a target pixel point in the lung region of interest includes:

[0037] In the lung region of interest in the electrical impedance static image, a pixel with the highest brightness value is selected as a target pixel, and an electrical impedance time variation curve corresponding to the target pixel is drawn;

[0038] In the electrical impedance time variation curve, a section of the curve including at least one peak point and one valley point is selected as a cardiac cycle;

[0039] Performing peak point detection processing on the impedance time variation curve corresponding to each pixel point in the impedance image sequence within the cardiac cycle to determine the peak pixel point corresponding to each pixel point in the impedance image sequence;

[0040] The peak pixel points are combined to obtain a peak pixel point image.

[0041] In a second aspect, the present disclosure further provides a device for determining phase distribution of cardiopulmonary regional signals, comprising:

[0042] An acquisition module, used for acquiring a target electrical impedance tomography signal synchronized with the cardiac mechanical motion of the subject among the electrical impedance tomography signals of the subject's chest at multiple detection moments;

[0043] A first determination module is used to determine an electrical impedance static image of the chest of the subject according to the target electrical impedance tomography signal at each detection moment;

[0044] A second determination module is used to respectively determine a heart region of interest and a lung region of interest of the subject in the electrical impedance static image;

[0045] A third determination module is used to determine a peak pixel point image according to an electrical impedance time variation curve corresponding to a target pixel point in the lung region of interest;

[0046] The calculation module is used to calculate the sum of the pixel points in the heart region of interest and the lung region of interest, and multiply the sum of the pixel points with each peak pixel point in the peak pixel point image one by one to obtain a phase distribution diagram of the heart and lung region signal of the subject.

[0047] In a third aspect, the present disclosure further provides a computer device, comprising a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the above method.

[0048] In a fourth aspect, the present disclosure further provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the above method when executed by a processor.

[0049] In a fifth aspect, the present disclosure also provides a computer program product, including a computer program, which implements the steps of the above method when executed by a processor.

[0050] The present disclosure provides a method, device and equipment for determining the phase distribution of a cardiopulmonary region signal, which collects a target impedance tomography signal synchronized with the subject's cardiac mechanical motion from the impedance tomography signal of the subject's chest at multiple detection moments; determines an impedance static image of the subject's chest according to the target impedance tomography signal at each detection moment; determines the subject's cardiac region of interest and lung region of interest in the impedance static image respectively; determines a peak pixel point image according to the impedance time variation curve corresponding to the target pixel point in the lung region of interest; calculates the sum of the pixel points in the cardiac region of interest and the lung region of interest, multiplies the sum of the pixel points with each peak pixel point in the peak pixel point image one by one, and obtains a phase distribution diagram of the subject's cardiopulmonary region signal. In this way, the voltage signal synchronized with the cardiac mechanical motion can be matched with the spatial position, thereby accurately reflecting the phase distribution of the subject's cardiopulmonary region blood flow signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The present disclosure will be described in more detail below based on embodiments and with reference to the accompanying drawings:

[0052] Figure 1 A schematic flow chart of a method for determining phase distribution of a cardiopulmonary region signal provided in an embodiment of the present disclosure;

[0053] Figure 2 A voltage signal obtained by measuring a healthy subject under the end-inspiratory breath-hold condition provided in an embodiment of the present disclosure;

[0054] Figure 3 The electrical impedance image a in the electrical impedance image sequence provided by the embodiment of the present disclosure;

[0055] Figure 4 The electrical impedance image b in the electrical impedance image sequence provided by the embodiment of the present disclosure;

[0056] Figure 5 The electrical impedance image c in the electrical impedance image sequence provided by the embodiment of the present disclosure;

[0057] Figure 6 The electrical impedance image d in the electrical impedance image sequence provided by the embodiment of the present disclosure;

[0058] Figure 7 The electrical impedance static image provided by the embodiment of the present disclosure;

[0059] Figure 8Images of regions of interest of the heart and lungs provided for embodiments of the present disclosure;

[0060] Fig. 9 A schematic diagram of selecting target pixel points in a lung region of interest of an electrical impedance static image provided by an embodiment of the present disclosure;

[0061] Fig.10 The electrical impedance time variation curve corresponding to the target pixel point provided in the embodiment of the present disclosure, and a schematic diagram of a cardiac cycle selected therein;

[0062] Fig.11 The peak pixel point image provided by the embodiment of the present disclosure;

[0063] Fig.12 A phase distribution diagram of the cardiopulmonary region signal of the subject provided in the embodiment of the present disclosure;

[0064] Fig.13 Another flowchart of the method for determining the phase distribution of the cardiopulmonary region signal provided in the embodiment of the present disclosure;

[0065] Fig.14 A schematic diagram of a module of a device for determining phase distribution of cardiopulmonary regional signals provided in an embodiment of the present disclosure.

[0066] In the drawings, the same reference numerals are used for the same components and the drawings are not drawn to scale. DETAILED DESCRIPTION

[0067] In order to enable those skilled in the art to better understand the technical solution of the present disclosure, and to fully understand and implement how the present disclosure applies technical means to solve technical problems and achieve the corresponding technical effects, the technical solution in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only embodiments of a part of the present disclosure, not all of the embodiments. The embodiments of the present disclosure and the various features in the embodiments can be combined with each other without conflict, and the technical solutions formed are all within the scope of protection of the present disclosure. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of the present disclosure.

[0068] It should be noted that the terms "first", "second", etc. in the specification and claims of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present disclosure described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products, or devices.

[0069] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0070] It should be noted that the existing technology extracts the voltage signal synchronized with the mechanical movement of the heart from the original measured voltage signal, and then directly averages the channel dimension, and considers that the obtained average curve (time signal) is the curve that conforms to the phase characteristics of the cardiogenic signal. The obtained result is difficult to interpret and difficult to reflect the true phase distribution of the cardiogenic signal. The method for determining the phase distribution of the cardiopulmonary regional signal disclosed in the present invention displays and quantifies the phase distribution of the cardiopulmonary regional cardiogenic signal of the subject based on the electrical impedance image sequence, which provides an effective means for subsequent phase-based signal processing.

[0071] Embodiment 1

[0072] Figure 1 The flowchart of a method for determining the phase distribution of a cardiopulmonary region signal provided by an embodiment of the present disclosure is as follows. Figure 1 As shown, a method for determining phase distribution of cardiopulmonary region signals includes:

[0073] Step 101, collecting a target electrical impedance tomography signal synchronized with the cardiac mechanical motion of the subject from among the electrical impedance tomography signals of the subject's chest at multiple detection moments;

[0074] Step 102, determining an electrical impedance static image of the chest of the subject according to the target electrical impedance tomography signal at each detection moment;

[0075] Step 103, respectively determining a heart region of interest and a lung region of interest of the subject in the electrical impedance static image;

[0076] Step 104, determining a peak pixel point image according to the electrical impedance time variation curve corresponding to the target pixel point in the lung region of interest;

[0077] Step 105, calculating the sum of the pixels in the heart region of interest and the lung region of interest, multiplying the sum of the pixels with each peak pixel in the peak pixel image one by one, and obtaining a phase distribution diagram of the heart and lung region signal of the subject.

[0078] In this embodiment, the impedance tomography signal of the chest of the subject is measured during spontaneous breathing or breath holding, and the target impedance tomography signal synchronized with the mechanical movement of the heart of the subject is extracted therefrom. According to the target impedance tomography signal, an impedance static image of the chest of the subject is constructed, and the heart region of interest and the lung region of interest of the subject are respectively determined in the impedance static image, and the peak pixel point image is determined according to the impedance time variation curve corresponding to the target pixel point in the lung region of interest, and the heart region of interest and the lung region of interest are multiplied with the peak pixel point image to obtain the phase distribution diagram of the heart and lung region signal of the subject. In this way, the voltage signal synchronized with the mechanical movement of the heart can be matched with the spatial position, so as to accurately reflect the phase distribution of the blood flow signal of the heart and lung region of the subject.

[0079] Embodiment 2

[0080] Based on the above embodiment, step 101 may include:

[0081] Step 1011, after applying an excitation current or an excitation voltage to the body of the subject through some electrodes placed around the chest of the subject, data measurements are performed at multiple measurement moments on the remaining electrodes to obtain electrical signals; the electrical signals include current signals or voltage signals;

[0082] Step 1012, performing signal extraction processing on the electrical signal according to the mechanical movement frequency of the heart of the subject, to obtain a target electrical signal in the electrical signal that is synchronized with the mechanical movement of the heart of the subject.

[0083] Specifically, an excitation current may be applied to the body of the subject by placing some electrodes around the chest of the subject, and voltage measurements are performed on the remaining electrodes at multiple measurement moments to obtain the following: Figure 2 The voltage signal shown; Figure 2A voltage signal (average curve of each channel) is measured by a healthy subject under the condition of breath holding at the end of inspiration, and then the voltage signal is subjected to signal extraction processing according to the mechanical movement frequency of the heart of the subject to obtain a target voltage signal in the voltage signal that is synchronized with the mechanical movement of the heart of the subject;

[0084] Alternatively, an excitation voltage is applied to the body of the subject by placing some electrodes around the chest of the subject, and current measurements are performed on the remaining electrodes at multiple measurement times to obtain a current signal; then, based on the mechanical movement frequency of the subject's heart, the current signal is subjected to signal extraction processing to obtain a target current signal in the current signal that is synchronized with the mechanical movement of the subject's heart.

[0085] Exemplarily, 16 electrodes are placed around the chest of the subject, and after applying an excitation current to the subject's body through 8 of the electrodes, voltage is measured on the remaining 8 electrodes to obtain a target voltage signal; as another embodiment, after applying an excitation voltage to the subject's body through 8 of the electrodes, current is measured on the remaining 8 electrodes to obtain a target current signal.

[0086] In this embodiment, by acquiring a target current signal or a target voltage signal synchronized with the mechanical movement of the subject's heart, the contraction and relaxation process of the subject's heart can be accurately reflected in the target current signal or the target voltage signal, and it can be detected whether the subject's heart has abnormal conditions such as weak contraction or limited relaxation, thereby obtaining the accurate phase distribution of the subject's cardiopulmonary regional signal.

[0087] Embodiment 3

[0088] Figures 3 to 6 The electrical impedance images a to d in the electrical impedance image sequence provided by the embodiment of the present disclosure are: Figure 7 The electrical impedance static image provided by the embodiment of the present disclosure is as follows: Figures 3 to 7 As shown, based on the above embodiment, step 102 may include:

[0089] Step 1021, constructing an electrical impedance image sequence of the chest of the subject according to the target electrical impedance tomography signal at each detection moment;

[0090] Step 1022: integrating the static electrical impedance image of the chest of the subject based on the electrical impedance image sequence.

[0091] The electrical impedance image sequence is a set of electrical impedance images generated by electrical impedance imaging and arranged in sequence according to a detection time length, and each electrical impedance image has a plurality of current data or voltage data;

[0092] The electrical impedance static image is an image obtained by integrating the electrical impedance image sequence.

[0093] In this embodiment, by constructing the impedance image sequence, the impedance change of the subject's chest within a detection period can be determined; by integrating the impedance static image, data processing can be simplified, and the impedance static image is more suitable for static feature extraction, which improves image stability and facilitates analysis and interpretation of impedance data.

[0094] Embodiment 4

[0095] Figures 3 to 6 The electrical impedance image a to the electrical impedance image d in the electrical impedance image sequence provided by the embodiment of the present disclosure are as follows: Figures 3 to 6 As shown, based on the above embodiment, step 1021 may include:

[0096] Step 10211, calculating the difference of the target electrical signal measured at every two adjacent detection moments among all the detection moments; the target electrical signal includes: a target voltage signal or a target current signal;

[0097] Step 10212, calculating the differential reconstruction function of the difference value to obtain the change in the conductivity in the chest cavity of the subject at each of the two adjacent detection moments;

[0098] Step 10213, determining the change in electrical impedance in the chest cavity of the subject at each of the two adjacent detection moments based on the change in electrical conductivity;

[0099] Step 10214, constructing an electrical impedance image sequence of the subject's chest according to the electrical impedance change.

[0100] It should be noted that the electrical impedance image sequence can be determined based on a variety of feasible algorithms. Specifically, the electrical impedance change in the chest cavity of the subject between the two adjacent detection moments can be determined by calculating the voltage difference between the two adjacent detection moments. The calculation formula for the electrical impedance change is:

[0101]

[0102] Wherein, ΔZ is the change in electrical impedance in the chest cavity of the measured person between the two detection moments, and Δσ is the change in electrical conductivity in the chest cavity of the measured person at the two adjacent moments;

[0103] Δσ=F(Δd)

[0104] Wherein, Δd is the voltage difference of the chest cavity of the measured person at two adjacent detection moments, Δσ is the change of conductivity in the chest cavity of the measured person at the two adjacent moments, and F is a function.

[0105] In this embodiment, by constructing the electrical impedance image sequence, the change of the electrical impedance of the chest of the subject within a detection period can be determined, thereby determining the physical change of the subject.

[0106] Embodiment 5

[0107] Figure 7 The electrical impedance static image provided by the embodiment of the present disclosure is as follows: Figure 7 As shown, based on the above embodiment, step 1022 may include:

[0108] Step 10221, obtaining an electrical impedance element matrix corresponding to the electrical impedance image sequence, wherein each row of the electrical impedance element matrix is ​​the electrical impedance of a target pixel point in the electrical impedance image sequence at a detection time;

[0109] Step 10222, calculating the average electrical impedance of all elements in the electrical impedance element matrix;

[0110] Step 10223, determining the slope and intercept of each pixel in the electrical impedance image sequence according to the electrical impedance of each pixel at each detection moment and the electrical impedance average value;

[0111] Step 10224, combining the slopes of the pixels in the electrical impedance image sequence to obtain a static electrical impedance image of the chest of the subject.

[0112] It should be noted that the impedance static image can be obtained based on a variety of feasible algorithms. Specifically, the impedance image sequence can be represented as an impedance element matrix A, each column in the impedance element matrix A is an impedance static image at a detection time, and each row is the impedance of a target pixel point in the impedance image sequence at a detection time, denoted as a i =(i=1, 2, ..., M), wherein M is the total number of rows of the electrical impedance element matrix A;

[0113] The calculation formula for the electrical impedance average value of all elements in the electrical impedance element matrix A is:

[0114]

[0115] in, is the average value of the electrical impedance of all elements in the electrical impedance element matrix A, a iis the electrical impedance value of the ith pixel at the first detection moment, and M is the total number of all detection moments.

[0116] The calculation formula for the slope and intercept of each pixel in the electrical impedance image sequence is:

[0117]

[0118] in, for and a i Linear regression of is the average value of the electrical impedance of all elements in the electrical impedance element matrix A, a i is the electrical impedance value of the ith pixel at the first detection moment, s i is the slope of each pixel in the electrical impedance image sequence, b i is the intercept of each pixel in the electrical impedance image sequence.

[0119] The slopes of the pixels in the electrical impedance image sequence are combined to obtain a static electrical impedance image of the chest of the subject, namely: static =(s1, s2, ..., s N ) T ;

[0120] Among them, I static is the static electrical impedance image of the chest of the subject, s1 is the slope of the first pixel in the electrical impedance image sequence, s2 is the slope of the second pixel in the electrical impedance image sequence, and s N is the slope of the Nth pixel in the electrical impedance image sequence, N is the total number of pixels in the electrical impedance image sequence, and T represents transposition.

[0121] In this embodiment, by integrating the electrical impedance static image, data processing can be simplified, and the electrical impedance static image is more suitable for static feature extraction, which improves image stability and facilitates analysis and interpretation of electrical impedance data.

[0122] Embodiment 6

[0123] Figure 8 The images of the regions of interest of the heart and lungs provided in the embodiments of the present disclosure are as follows: Figure 8 As shown, based on the above embodiment, step 103 may include:

[0124] Step 1031, determining the value of each pixel in the electrical impedance static image according to the slope of each pixel in the electrical impedance static image and a first preset threshold;

[0125] Step 1032, determining the lung region of interest of the subject according to the values ​​of each pixel point;

[0126] Among them, if the slope of the target pixel point in the electrical impedance static image is greater than the first preset threshold, the value of the target pixel point is 1, otherwise, the value of the target pixel point is 0, and the area composed of pixels corresponding to the value of 1 is determined as the lung area of ​​interest of the subject.

[0127] In a specific implementation, the lung region of interest of the subject can be determined according to the values ​​of the pixel points, that is:

[0128] ROI lung =(l1,l2,...,l K ) T

[0129] Among them, ROI lung is the lung region of interest of the subject, l1 is the value of the first pixel point in the electrical impedance image sequence, l2 is the value of the second pixel point in the electrical impedance image sequence, and l K is the value of the Kth pixel in the electrical impedance image sequence, K is the total number of pixels in the electrical impedance image sequence, and T represents transposition.

[0130] According to the slope of the i-th pixel in the electrical impedance static image and the first preset threshold, the value of the i-th pixel in the electrical impedance static image is determined, that is:

[0131]

[0132] Among them, li is the value of the i-th pixel in the electrical impedance image sequence, si is the slope of the i-th pixel in the electrical impedance image sequence, T1 is the first preset threshold, and K is the total number of pixels in the electrical impedance image sequence.

[0133] The region composed of the pixels corresponding to the pixel values ​​of 1 among all the pixels is determined as the lung region of interest of the subject.

[0134] The first preset threshold value can be determined according to the slope of each pixel in the electrical impedance image sequence, that is, T1=0.2×max(s1, s2, ..., s N );

[0135] Wherein, T1 is the first preset threshold, 0.2 is a constant, max is the maximum pixel value in the electrical impedance image sequence, s1 is the slope of the first pixel in the electrical impedance image sequence, s2 is the slope of the second pixel in the electrical impedance image sequence, and s Nis the slope of the Nth pixel in the electrical impedance image sequence, and N is the total number of pixels in the electrical impedance image sequence.

[0136] In this embodiment, by determining the lung region of interest of the subject, the pixel points in the lung region of interest can be processed to complete the spatial correspondence and accurately locate the lung phase distribution of the subject, making the result more accurate.

[0137] Embodiment 7

[0138] Figure 8 The images of the regions of interest of the heart and lungs provided in the embodiments of the present disclosure are as follows: Figure 8 As shown, based on the above embodiment, step 103 may include:

[0139] Step 1033, determining the value of each pixel in the electrical impedance static image according to the slope of each pixel in the electrical impedance static image and the second preset threshold;

[0140] Step 1034, determining the cardiac region of interest of the subject according to the values ​​of the pixels;

[0141] Among them, if the slope of the target pixel point in the electrical impedance static image is less than the second preset threshold, the value of the target pixel point is 1, otherwise, the value of the target pixel point is 0, and the area composed of pixels corresponding to the value of 1 is determined as the heart area of ​​interest of the subject.

[0142] In a specific implementation, the heart region of interest of the subject can be determined according to the values ​​of each pixel point, that is:

[0143] ROI heart =(l1,l2,...,l K ) T

[0144] Among them, ROI heart is the heart region of interest of the subject, l1 is the value of the first pixel point in the electrical impedance image sequence, l2 is the value of the second pixel point in the electrical impedance image sequence, and l K is the value of the Kth pixel in the electrical impedance image sequence, K is the total number of pixels in the electrical impedance image sequence, and T represents transposition.

[0145] According to the slope of the i-th pixel in the electrical impedance static image and the second preset threshold, the value of the i-th pixel in the electrical impedance static image is determined, that is:

[0146]

[0147] Among them, l i is the value of the i-th pixel in the electrical impedance image sequence, s i is the slope of the ith pixel in the electrical impedance image sequence, T2 is the second preset threshold, and K is the total number of pixels in the electrical impedance image sequence.

[0148] The region composed of the pixels corresponding to the pixel values ​​of 1 among all the pixels is determined as the heart region of interest of the subject.

[0149] The second preset threshold value can be determined according to the slope of each pixel in the electrical impedance image sequence, that is, T2=0.2×min(s1, s2, ..., s N );

[0150] Wherein, T2 is the second preset threshold, 0.2 is a constant, min is the minimum pixel value in the electrical impedance image sequence, s1 is the slope of the first pixel in the electrical impedance image sequence, s2 is the slope of the second pixel in the electrical impedance image sequence, and s N is the slope of the Nth pixel in the electrical impedance image sequence, and N is the total number of pixels in the electrical impedance image sequence.

[0151] In this embodiment, by determining the cardiac region of interest of the subject, the pixel points in the cardiac region of interest can be processed to complete the spatial correspondence and accurately locate the cardiac phase distribution of the subject, making the result more accurate.

[0152] Embodiment 8

[0153] Fig. 9 A schematic diagram of selecting target pixel points in a lung region of interest of an electrical impedance static image provided by an embodiment of the present disclosure, Fig.10 The electrical impedance time variation curve corresponding to the target pixel point provided in the embodiment of the present disclosure, and a schematic diagram of the cardiac cycle selected therein, such as Fig. 9 and Fig.10 As shown, based on the above embodiment, step 104 may include:

[0154] Step 1041, selecting a pixel with the highest brightness value in the lung region of interest in the electrical impedance static image as a target pixel, and drawing an electrical impedance time variation curve corresponding to the target pixel;

[0155] Step 1042, selecting a curve section including at least one peak point and one valley point in the electrical impedance time variation curve as a cardiac cycle;

[0156] Step 1043, performing peak point detection processing on the electrical impedance time variation curve corresponding to each pixel point in the electrical impedance image sequence within the cardiac cycle to determine the peak pixel point corresponding to each pixel point in the electrical impedance image sequence;

[0157] Step 1044, combining the peak pixel points to obtain a peak pixel point image.

[0158] It should be noted that if Fig. 9 As shown, the pixel point shown by the coordinates X, Y (38, 49) is the target pixel point, such as Fig.10 As shown, the dotted box shows the cardiac cycle.

[0159] In this embodiment, based on the electrical impedance image sequence, the electrical impedance time variation curve of each pixel i (i=1, 2, ..., N) is detected at a peak point within the cardiac cycle to obtain a peak pixel point, and all the peak pixel points are combined together to obtain a peak pixel point image I peak ;

[0160] I peak =(p1, p2, ..., p L ) T

[0161] Among them, I peak is the peak pixel image, p1 is the first peak pixel, p2 is the second peak pixel, p N is the Lth peak pixel, L is the total number of peak pixels, and T represents transposition.

[0162] The peak pixel image has prominent features and is easy to highlight abnormal areas, which can simplify data processing, reduce calculation complexity, and accelerate the operation of the algorithm.

[0163] Embodiment 9

[0164] Fig.11 The peak pixel point image provided by the embodiment of the present disclosure, Fig.12 The phase distribution diagram of the cardiopulmonary region signal of the subject provided in the embodiment of the present disclosure is as follows: Fig.11 and Fig.12 As shown, based on the above embodiment, step 105 may include:

[0165] Step 1051, calculate the sum of the pixels in the heart region of interest and the lung region of interest, multiply the sum of the pixels with each peak pixel in the peak pixel image one by one, and obtain a phase distribution diagram of the heart and lung region signal of the subject.

[0166] Specifically, the sum of the pixels in the heart region of interest and the lung region of interest is multiplied one by one with each peak pixel in the peak pixel image to obtain a phase distribution diagram of the heart and lung region signal of the subject, that is:

[0167] I phase =I peak ⊙(ROI lung +ROI heart )

[0168] Among them, I phase is the phase distribution diagram of the cardiopulmonary region signal of the subject, I peak is the peak pixel image, ROI lung is the region of interest of the subject's lungs, ROI heart is the heart region of interest of the subject, and ⊙ represents pixel-by-pixel multiplication.

[0169] In this embodiment, based on the pixel points in the heart region of interest and the lung region of interest of the subject, as well as the peak pixel points, the phase distribution of the cardiopulmonary regional signals of the subject can be accurately determined, thereby accurately reflecting the heart and lung functions of the subject and making a true and accurate assessment of the cardiopulmonary function of the subject.

[0170] Embodiment 10

[0171] Based on the above embodiments, this embodiment provides an application example.

[0172] Fig.13 Another flow chart of the method for determining the phase distribution of the cardiopulmonary region signal provided in the embodiment of the present disclosure is as follows: Fig.13 As shown, a specific implementation process of a method for determining phase distribution of cardiopulmonary region signals may include:

[0173] Step 1301: collecting target electrical impedance tomography signals from the chest of the subject;

[0174] Step 1302: constructing an electrical impedance image sequence according to the target electrical impedance tomography signal;

[0175] Step 1303: integrating the electrical impedance static image according to the electrical impedance image sequence;

[0176] Step 1304: Generate a lung region of interest and a heart region of interest of the subject based on the electrical impedance static image;

[0177] Step 1305: determining a target pixel point in the lung region of interest and locating a cardiac cycle;

[0178] Step 1306: performing peak point detection pixel by pixel in the cardiac cycle to determine a peak pixel point image;

[0179] Step 1307: Determine a phase distribution diagram of the cardiopulmonary region signal of the subject according to the pixel points in the lung region of interest and the heart region of interest and the peak pixel points in the peak pixel point image.

[0180] In this embodiment, the method for determining the phase distribution of the cardiopulmonary regional signal can correspond the voltage signal synchronized with the mechanical movement of the heart to the spatial position, thereby accurately reflecting the phase distribution of the cardiopulmonary regional blood flow signal of the subject.

[0181] Embodiment 11

[0182] Fig.14 A schematic diagram of a module of a device for determining phase distribution of a cardiopulmonary region signal provided by an embodiment of the present disclosure. Fig.14 As shown, a device 140 for determining phase distribution of cardiopulmonary region signals includes:

[0183] The acquisition module 141 is used to acquire a target electrical impedance tomography signal synchronized with the cardiac mechanical motion of the subject from among the electrical impedance tomography signals of the subject's chest at multiple detection moments;

[0184] A first determination module 142 is used to determine an electrical impedance static image of the chest of the subject according to the target electrical impedance tomography signal at each detection moment;

[0185] A second determination module 143 is used to respectively determine a heart region of interest and a lung region of interest of the subject in the electrical impedance static image;

[0186] A third determination module 144 is used to determine a peak pixel point image according to an electrical impedance time variation curve corresponding to a target pixel point in the lung region of interest;

[0187] The calculation module 145 is used to calculate the sum of the pixels in the heart region of interest and the lung region of interest, and multiply the sum of the pixels with each peak pixel in the peak pixel image one by one to obtain a phase distribution diagram of the heart and lung region signal of the subject.

[0188] In some embodiments, the acquisition module 141 may be used to:

[0189] After applying an excitation current or an excitation voltage to the body of the subject through some electrodes placed around the chest of the subject, data measurements are performed at multiple measurement moments on the remaining electrodes to obtain electrical signals; the electrical signals include current signals or voltage signals;

[0190] According to the mechanical movement frequency of the heart of the subject, the electrical signal is subjected to signal extraction processing to obtain a target electrical signal in the electrical signal that is synchronized with the mechanical movement of the heart of the subject.

[0191] In some embodiments, the first determining module 142 may be used to:

[0192] constructing an electrical impedance image sequence of the chest of the subject according to the target electrical impedance tomography signal at each detection moment;

[0193] Based on the electrical impedance image sequence, an electrical impedance static image of the subject's chest is integrated.

[0194] In some embodiments, the first determining module 142 may also be used to:

[0195] Calculate the difference between the target electrical signals measured at every two adjacent detection moments among all detection moments;

[0196] Calculating a differential reconstruction function of the difference to obtain a change in the electrical conductivity in the chest cavity of the subject at each of the two adjacent detection moments;

[0197] Determining the change in electrical impedance in the chest cavity of the subject at each of the two adjacent detection moments based on the change in electrical conductivity;

[0198] An electrical impedance image sequence of the chest of the subject is constructed according to the electrical impedance change.

[0199] In some embodiments, the first determining module 142 may also be used to:

[0200] Acquire an electrical impedance element matrix corresponding to the electrical impedance image sequence, wherein each row of the electrical impedance element matrix is ​​the electrical impedance of a target pixel point in the electrical impedance image sequence at a detection time;

[0201] Calculating the electrical impedance average value of all elements in the electrical impedance element matrix;

[0202] Determine the slope and intercept of each pixel in the electrical impedance image sequence according to the electrical impedance of each pixel at each detection moment and the electrical impedance average value;

[0203] The slopes of the pixels in the electrical impedance image sequence are combined to obtain a static electrical impedance image of the chest of the subject.

[0204] In some embodiments, the second determining module 143 may be used to:

[0205] Determining the value of each pixel in the electrical impedance static image according to the slope of each pixel in the electrical impedance static image and a first preset threshold;

[0206] Determine the lung region of interest of the subject according to the values ​​of each pixel point;

[0207] Among them, if the slope of the target pixel point in the electrical impedance static image is greater than the first preset threshold, the value of the target pixel point is 1, otherwise, the value of the target pixel point is 0, and the area composed of pixels corresponding to the value of 1 is determined as the lung area of ​​interest of the subject.

[0208] In some embodiments, the second determining module 143 may also be used to:

[0209] Determine the value of each pixel in the electrical impedance static image according to the slope of each pixel in the electrical impedance static image and a second preset threshold;

[0210] Determine the cardiac region of interest of the subject according to the values ​​of each pixel point;

[0211] Among them, if the slope of the target pixel point in the electrical impedance static image is less than the second preset threshold, the value of the target pixel point is 1, otherwise, the value of the target pixel point is 0, and the area composed of pixels corresponding to the value of 1 is determined as the heart area of ​​interest of the subject.

[0212] In some embodiments, the third determination module 144 may be used to:

[0213] In the lung region of interest in the electrical impedance static image, a pixel with the highest brightness value is selected as a target pixel, and an electrical impedance time variation curve corresponding to the target pixel is drawn;

[0214] In the electrical impedance time variation curve, a section of the curve including at least one peak point and one valley point is selected as a cardiac cycle;

[0215] Performing peak point detection processing on the impedance time variation curve corresponding to each pixel point in the impedance image sequence within the cardiac cycle to determine the peak pixel point corresponding to each pixel point in the impedance image sequence;

[0216] The peak pixel points are combined to obtain a peak pixel point image.

[0217] In this embodiment, the impedance tomography signal of the chest of the subject is measured during spontaneous breathing or breath holding, and the target impedance tomography signal synchronized with the mechanical movement of the heart of the subject is extracted therefrom. According to the target impedance tomography signal, an impedance static image of the chest of the subject is constructed, and the heart region of interest and the lung region of interest of the subject are respectively determined in the impedance static image, and the peak pixel point image is determined according to the impedance time variation curve corresponding to the target pixel point in the lung region of interest, and the heart region of interest and the lung region of interest are multiplied with the peak pixel point image to obtain the phase distribution diagram of the heart and lung region signal of the subject. In this way, the voltage signal synchronized with the mechanical movement of the heart can be matched with the spatial position, so as to accurately reflect the phase distribution of the blood flow signal of the heart and lung region of the subject.

[0218] It should be noted that the device for determining the phase distribution of the cardiopulmonary regional signal is a device corresponding to the method for determining the phase distribution of the cardiopulmonary regional signal mentioned above, and all implementation methods of the method for determining the phase distribution of the cardiopulmonary regional signal in the above-mentioned device for determining the phase distribution of the cardiopulmonary regional signal are applicable to the embodiments of the device for determining the phase distribution of the cardiopulmonary regional signal, and can also achieve the same technical effect.

[0219] Embodiment 12

[0220] On the basis of the above embodiments, this embodiment provides a computer device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method described in the above embodiments.

[0221] In some implementations of this embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method described in the above embodiment are implemented.

[0222] In some implementations of this embodiment, a computer program product is provided, including a computer program / instructions, and when the computer program is executed by a processor, the steps of the method described in the above embodiment are implemented.

[0223] The processor may include, but is not limited to, one or more processors or microprocessors. Each processor may be an application specific integrated circuit (ASIC), a digital signal processor (DSP), a digital signal processing device (DSPD), a programmable logic device (PLD), a field programmable gate array (FPGA), a controller, a microcontroller, a microprocessor or other electronic components to execute the method in the above embodiments.

[0224] Computer-readable storage media can be implemented by any type of volatile or non-volatile storage device or a combination thereof. Computer-readable storage media may include, but are not limited to, for example, random access memory (RAM), read-only memory (ROM), flash memory, EPROM memory, EEPROM memory, registers, computer storage media (such as hard disks, floppy disks, solid-state drives, removable disks, Blu-ray disks, etc.).

[0225] The computer-readable storage medium may also store at least one computer executable program / instruction, which may be, for example, a computer-readable instruction. The computer-readable storage medium includes, but is not limited to, for example, a volatile memory and / or a non-volatile memory. The volatile memory may include, for example, a random access memory (RAM) and / or a cache memory (cache), etc. The computer-readable storage medium may include, for example, a read-only memory (ROM), a hard disk, a flash memory, etc. For example, a non-transitory computer-readable storage medium may be connected to a computing device such as a computer, and then, when the computing device runs the computer-readable instructions stored on the computer-readable storage medium, the various methods described above may be performed.

[0226] In addition, the computer device may also include (but not limited to) a data bus, an input / output (I / O) bus, a display, and input / output devices (eg, keyboard, mouse, speaker, etc.), etc.

[0227] The processor may communicate with external devices via an I / O bus via a wired or wireless network.

[0228] In one embodiment, the at least one computer executable instruction may also be compiled into or constitute a software product / computer program product, wherein one or more computer executable instructions are executed by a processor to perform the various functions and / or method steps in the embodiments described in the present technology.

[0229] In the embodiments provided in the present disclosure, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely schematic. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices, methods and computer program products according to multiple embodiments of the present disclosure. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the above-mentioned module, program segment or a part of the code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0230] It should be noted that in the present disclosure, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element limited by the sentence "includes a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0231] Although the embodiments disclosed in the present disclosure are as above, the above contents are only embodiments adopted for facilitating the understanding of the present disclosure and are not intended to limit the present disclosure. Any technician in the technical field to which the present disclosure belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present disclosure, but the scope of patent protection of the present disclosure shall still be subject to the scope defined in the attached claims.

Claims

1. A method for determining phase distribution of cardiopulmonary regional signals, characterized in that: include: Collecting a target electrical impedance tomography signal synchronized with the cardiac mechanical movement of the subject from among the electrical impedance tomography signals of the subject's chest at multiple detection moments; Determining an electrical impedance static image of the chest of the subject according to the target electrical impedance tomography signal at each detection moment; Determining the heart region of interest and the lung region of interest of the subject in the electrical impedance static image respectively; Determine a peak pixel point image according to an electrical impedance time variation curve corresponding to a target pixel point in the lung region of interest; The sum of the pixels in the heart region of interest and the lung region of interest is calculated, and the sum of the pixels is multiplied by each peak pixel in the peak pixel image one by one to obtain a phase distribution diagram of the heart and lung region signal of the subject.

2. The method for determining the phase distribution of cardiopulmonary regional signals according to claim 1, characterized in that: Collecting a target electrical impedance tomography signal synchronized with the cardiac mechanical motion of the subject from the electrical impedance tomography signals of the subject's chest at multiple detection moments, including: After applying an excitation current or an excitation voltage to the body of the subject through some electrodes placed around the chest of the subject, data measurements are performed at multiple measurement moments on the remaining electrodes to obtain electrical signals; the electrical signals include current signals or voltage signals; According to the mechanical movement frequency of the heart of the subject, the electrical signal is subjected to signal extraction processing to obtain a target electrical signal in the electrical signal that is synchronized with the mechanical movement of the heart of the subject.

3. The method for determining the phase distribution of cardiopulmonary regional signals according to claim 1, characterized in that: Determining an electrical impedance static image of the chest of the subject according to the target electrical impedance tomography signal at each detection moment includes: constructing an electrical impedance image sequence of the chest of the subject according to the target electrical impedance tomography signal at each detection moment; Based on the electrical impedance image sequence, an electrical impedance static image of the subject's chest is integrated.

4. The method for determining the phase distribution of the cardiopulmonary region signal according to claim 3, characterized in that: Constructing an electrical impedance image sequence of the chest of the subject according to the target electrical impedance tomography signal at each detection moment, including: Calculate the difference between the target electrical signals measured at every two adjacent detection moments among all detection moments; Calculating a differential reconstruction function of the difference to obtain a change in the electrical conductivity in the chest cavity of the subject at each of the two adjacent detection moments; Determining the change in electrical impedance in the chest cavity of the subject at each of the two adjacent detection moments based on the change in electrical conductivity; An electrical impedance image sequence of the chest of the subject is constructed according to the electrical impedance change.

5. The method for determining the phase distribution of cardiopulmonary regional signals according to claim 3, characterized in that: Integrating the electrical impedance static image of the chest of the subject based on the electrical impedance image sequence includes: Acquire an electrical impedance element matrix corresponding to the electrical impedance image sequence, wherein each row of the electrical impedance element matrix is ​​the electrical impedance of a target pixel point in the electrical impedance image sequence at a detection time; Calculating the electrical impedance average value of all elements in the electrical impedance element matrix; Determine the slope and intercept of each pixel in the electrical impedance image sequence according to the electrical impedance of each pixel at each detection moment and the electrical impedance average value; The slopes of the pixels in the electrical impedance image sequence are combined to obtain a static electrical impedance image of the chest of the subject.

6. The method for determining the phase distribution of cardiopulmonary regional signals according to claim 1, characterized in that: Determining a lung region of interest of the subject in the electrical impedance static image includes: Determining the value of each pixel in the electrical impedance static image according to the slope of each pixel in the electrical impedance static image and a first preset threshold; Determine the lung region of interest of the subject according to the values ​​of each pixel point; Among them, if the slope of the target pixel point in the electrical impedance static image is greater than the first preset threshold, the value of the target pixel point is 1, otherwise, the value of the target pixel point is 0, and the area composed of pixels corresponding to the value of 1 is determined as the lung area of ​​interest of the subject.

7. The method for determining the phase distribution of cardiopulmonary regional signals according to claim 1, characterized in that: Determining a cardiac region of interest of the subject in the electrical impedance static image comprises: Determine the value of each pixel in the electrical impedance static image according to the slope of each pixel in the electrical impedance static image and a second preset threshold; Determine the cardiac region of interest of the subject according to the values ​​of each pixel point; Among them, if the slope of the target pixel point in the electrical impedance static image is less than the second preset threshold, the value of the target pixel point is 1, otherwise, the value of the target pixel point is 0, and the area composed of pixels corresponding to the value of 1 is determined as the heart area of ​​interest of the subject.

8. The method for determining the phase distribution of cardiopulmonary regional signals according to claim 1, characterized in that: Determining a peak pixel point image according to an electrical impedance time variation curve corresponding to a target pixel point in the lung region of interest includes: In the lung region of interest in the electrical impedance static image, a pixel with the highest brightness value is selected as a target pixel, and an electrical impedance time variation curve corresponding to the target pixel is drawn; In the electrical impedance time variation curve, a section of the curve including at least one peak point and one valley point is selected as a cardiac cycle; Performing peak point detection processing on the impedance time variation curve corresponding to each pixel point in the impedance image sequence within the cardiac cycle to determine the peak pixel point corresponding to each pixel point in the impedance image sequence; The peak pixel points are combined to obtain a peak pixel point image.

9. A device for determining phase distribution of cardiopulmonary region signals, characterized in that: include: An acquisition module, used for acquiring a target electrical impedance tomography signal synchronized with the cardiac mechanical motion of the subject among the electrical impedance tomography signals of the subject's chest at multiple detection moments; A first determination module is used to determine an electrical impedance static image of the chest of the subject according to the target electrical impedance tomography signal at each detection moment; A second determination module is used to respectively determine a heart region of interest and a lung region of interest of the subject in the electrical impedance static image; A third determination module is used to determine a peak pixel point image according to an electrical impedance time variation curve corresponding to a target pixel point in the lung region of interest; The calculation module is used to calculate the sum of the pixel points in the heart region of interest and the lung region of interest, and multiply the sum of the pixel points with each peak pixel point in the peak pixel point image one by one to obtain a phase distribution diagram of the heart and lung region signal of the subject.

10. A computer device comprising a memory, a processor and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the steps of the method according to any one of claims 1 to 8.

11. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 8 are implemented.

12. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 8 are implemented.

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