CN111399038B - Slope parameter extraction method and device and computer readable storage medium - Google Patents

Slope parameter extraction method and device and computer readable storage medium Download PDF

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CN111399038B
CN111399038B CN201910002351.9A CN201910002351A CN111399038B CN 111399038 B CN111399038 B CN 111399038B CN 201910002351 A CN201910002351 A CN 201910002351A CN 111399038 B CN111399038 B CN 111399038B
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coordinates
coordinate
slope
maximum
propagation distance
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CN111399038A (en
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许晓臣
何琼
邵金华
孙锦
段后利
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Wuxi Hisky Medical Technologies Co Ltd
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Wuxi Hisky Medical Technologies Co Ltd
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
    • G01V1/28—Processing seismic data, e.g. analysis, for interpretation, for correction
    • G01V1/282—Application of seismic models, synthetic seismograms
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F17/00—Digital computing or data processing equipment or methods, specially adapted for specific functions
    • G06F17/10—Complex mathematical operations
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A10/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE at coastal zones; at river basins
    • Y02A10/23—Dune restoration or creation; Cliff stabilisation

Abstract

The application provides a slope parameter extraction method, a device and a computer readable storage medium, comprising: acquiring a variable of a test signal propagating along a preset direction at a position to be tested along with time; determining the coordinate where the most value of the variable corresponding to each propagation distance in the preset direction is located, and obtaining the most value coordinate corresponding to each propagation distance; and fitting the most-valued coordinates corresponding to the propagation distances to obtain the slope parameters of the position to be measured. According to the method and the device, the most-valued coordinates corresponding to each propagation distance are obtained based on the variable propagated by the test signal along the preset direction along with the time at the position to be tested, and the slope parameter of the position to be tested is obtained through fitting.

Description

Slope parameter extraction method and device and computer readable storage medium
Technical Field
The present application relates to the field of data processing, and in particular, to a method and an apparatus for extracting a slope parameter, and a computer-readable storage medium.
Background
In applications of tracking wave propagation speed such as ultrasonic elastography, geological exploration, seismic wave detection and the like, wave speed detection is involved, namely, the propagation process of wave features along the interested propagation direction in a certain time is detected.
At present, a slope parameter is extracted by adopting an image processing method to obtain a propagation speed, and because the process of wave propagation under actual conditions is complex, the imaging quality of strain data is generally poor, and thus the slope parameter obtained by the existing method is often inaccurate.
Content of application
The application provides a slope parameter extraction method, a slope parameter extraction device and a computer-readable storage medium, which are used for solving the problem that the slope parameter obtained by the existing method is inaccurate.
A first aspect of the present application provides a slope parameter extraction method, including: acquiring a variable of a test signal propagating along a preset direction at a position to be tested along with time; determining the coordinate of the maximum value of the variable corresponding to each propagation distance in the preset direction, and obtaining the maximum value coordinate corresponding to each propagation distance; and fitting the most-valued coordinates corresponding to the propagation distances to obtain the slope parameters of the position to be measured.
Another aspect of the present application provides a slope parameter extracting apparatus, including: the acquisition module is used for acquiring a variable of the propagation of the test signal along a preset direction at the position to be tested along with time; the determining module is used for determining the coordinate where the most value of the variable corresponding to each propagation distance in the preset direction is located, and obtaining the most value coordinate corresponding to each propagation distance; and the processing module is used for fitting and processing the most-valued coordinates corresponding to the propagation distances to obtain the slope parameter of the position to be measured.
Another aspect of the present application provides a slope parameter extracting apparatus, including: at least one processor and memory; the memory stores computer execution instructions; the at least one processor executes computer-executable instructions stored by the memory to perform the method as previously described.
Yet another aspect of the application is to provide a computer readable storage medium having a computer program stored therein, which when executed, implements the method as described above.
According to the slope parameter extraction method, the slope parameter extraction device and the computer readable storage medium, the most-valued coordinates corresponding to each propagation distance are obtained based on the variable of the test signal propagating along the preset direction along with the time at the position to be detected, and the slope parameter of the position to be detected is obtained through fitting.
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In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
Fig. 1A is a schematic flowchart of a slope parameter extraction method according to an embodiment of the present disclosure;
fig. 1B is a schematic flowchart of another slope parameter extraction method according to an embodiment of the present disclosure;
fig. 1C is a schematic flowchart of another slope parameter extraction method according to an embodiment of the present disclosure;
fig. 2 is a schematic flow chart illustrating a slope parameter extraction method according to a second embodiment of the present disclosure;
fig. 3 is a schematic flowchart of a slope parameter extraction method provided in the third embodiment of the present application;
fig. 4 is a schematic flowchart of a slope parameter extraction method according to a fourth embodiment of the present disclosure;
fig. 5 is a schematic structural diagram of an apparatus for extracting a slope parameter according to an eighth embodiment of the present application.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments in the present application without making any creative effort belong to the protection scope of the present application.
Fig. 1A is a schematic flow chart of a slope parameter extraction method according to an embodiment of the present disclosure, as shown in fig. 1A, the embodiment is exemplified by applying the slope parameter extraction method to a slope parameter extraction device, and the slope parameter extraction method includes:
step 101, acquiring a variable of a test signal transmitted along a preset direction at a position to be tested along with time;
step 102, determining coordinates where the most values of the variables corresponding to the propagation distances in the preset direction are located, and obtaining the most value coordinates corresponding to the propagation distances;
and 103, fitting the most-valued coordinates corresponding to the propagation distances to obtain slope parameters of the position to be measured.
The form of the test signal may be various, for example, acoustic wave, shear wave, etc. The variable may be any variable that reflects the characteristics of the wave, such as deformation data displacement values, strain values, and the like. The direction may be set in combination with an actual scene of the test signal, for example, when the application scene is elastography, the test signal may be a shear wave, and the preset direction may be a depth direction. The propagation distance refers to a distance from a currently arriving position to a propagation starting point when the test signal is propagated along a preset direction. For example, when the test signal propagates in the depth direction, each propagation distance is each depth. The slope parameter extracting method is applied to a slope parameter extracting device in the embodiment, and the slope parameter extracting device may be implemented in various forms, for example, a computer program stored in a storage medium, or software installed in an entity device, or an entity device, where the entity device includes, but is not limited to, an ultrasound imaging device, a computer, a terminal, a chip, and the like.
Compared with the existing method for obtaining the slope parameter by adopting an image processing method, the method has the advantages that the most-valued coordinates of the variables corresponding to different propagation distances of the test signal propagating in the preset direction are determined, and the slope parameter is obtained by fitting. According to the scheme, the slope parameter is obtained by fitting the best coordinate with good data quality, and the accurate slope parameter can be obtained even under the condition of high noise interference.
Optionally, fig. 1B is a schematic flow chart of another slope parameter extraction method provided in the first embodiment of the present application, as shown in fig. 1B, based on the implementation shown in fig. 1A, step 102 may specifically include:
step 1021, after acquiring a variable of the test signal propagating along a preset direction along with time at the position to be tested, generating a signal propagation diagram;
step 1022, determining an initial most value coordinate from the initial region to be measured of the signal propagation map, and taking the initial most value coordinate as a current most value coordinate;
and 1023, starting from the corresponding position of the current maximum coordinate in the next propagation distance, searching the maximum coordinate corresponding to the next propagation distance in the signal propagation diagram along the time direction, updating the maximum coordinate to the current maximum coordinate, and so on until the maximum coordinate corresponding to each propagation distance in the signal propagation diagram is searched.
The signal propagation diagram reflects variable characteristics of the test signal which propagates along a preset direction along with time at the position to be tested. Still with elastography scenarios as examples: the preset direction is the tissue depth direction, and correspondingly, the signal propagation diagram comprises the propagation information of the test signal at the tissue position to be tested at different depths at different moments.
The executing body of the embodiment may be a slope parameter extracting device, and the slope parameter extracting device may be disposed in the elasticity detecting apparatus. Specifically, in the process of performing elastography on a tissue, a test signal needs to be excited in the tissue, for example, a shear wave is excited in the tissue by means of an acoustic radiation force, echo data including propagation information of the shear wave in the tissue is then acquired, and deformation estimation data including deformation data of the shear wave at a position to be measured at different depths at different times is obtained by using the echo data. Based on the data, a corresponding time-depth data map (namely the signal propagation map) is generated, the deformation data are in a stripe shape in the data map, and the slope of the stripe is the tissue slope parameter of the position to be detected. The horizontal axis of the data map may be a time axis, and the vertical axis may be a depth axis representing the propagation distance, and accordingly, the abscissa of each coordinate point in the data map is a time coordinate, and the ordinate is a depth coordinate representing the propagation distance.
In this embodiment, the maximum coordinate may be a maximum coordinate, a minimum coordinate, a maximum coordinate, and a minimum coordinate. Specifically, the range and the position of the initial region to be measured may be specified in the signal propagation map according to the requirement, the coordinate where the maximum variable value or the minimum variable value in the initial region to be measured is the initial maximum coordinate, that is, the current maximum coordinate, and the propagation distance where the initial maximum coordinate is located/is the initial propagation distance, that is, the current propagation distance. The propagation distance is the total propagation distance between the starting propagation distance and the ending propagation distance in the signal propagation map. The end propagation distance may be a certain propagation distance specified according to requirements, but the propagation distance is greater than the start propagation distance, or may be the maximum propagation distance in the signal propagation diagram.
If the coordinate is the coordinate of the maximum variable value in the initial region to be measured, the maximum coordinate is the maximum coordinate; if the coordinate is the coordinate where the minimum variable value is located, the most significant coordinate is the minimum coordinate.
Regarding the process of determining the most significant coordinates, taking the actual scene as an example: based on the current signal propagation diagram, determining the initial maximum coordinate from the initial region to be measured of the signal propagation diagram, then searching the maximum point of the variable along the time direction from the corresponding position of the initial maximum coordinate in the next propagation distance, taking the maximum point as the maximum coordinate of the next propagation distance, and so on, and obtaining a series of maximum coordinates in a self-adaptive manner, wherein the maximum coordinate may be the maximum coordinate or the minimum coordinate. In this embodiment and the following embodiments, when the maximum value coordinate includes the maximum value coordinate and the minimum value coordinate, the operations performed on the maximum value coordinate and the minimum value coordinate are performed independently. According to the embodiment, the coordinate point with better effect can be obtained for fitting, so that more accurate slope parameters can be obtained.
In the embodiment, the most-valued coordinate required by fitting the straight line is found in a self-adaptive manner, namely, in the processing and analyzing processes, the processing method is automatically adjusted according to the data characteristics of the processed data, and the most-valued coordinate is determined by adaptively finding the starting point of the stripe, so that a most-valued coordinate point with a better effect is obtained for fitting, and a more accurate slope parameter is obtained.
The fitting process may be performed in various manners, for example, fitting may be performed by using a least square method, a linear fitting method, or a polynomial fitting method, so as to obtain a slope parameter. Optionally, fig. 1C is a schematic flow diagram of another slope parameter extraction method provided in an embodiment of the present application, and as shown in fig. 1C, on the basis of any one of the foregoing embodiments, when the most value coordinate includes a maximum value coordinate or a minimum value coordinate, step 103 may specifically include:
step 1031, fitting the most-valued coordinates corresponding to the propagation distances to obtain a target fitting straight line;
and step 1032, taking the slope of the target fitting straight line as a slope parameter of the position to be measured.
Alternatively, the fitting may be performed using/based on least squares, linear fitting, or polynomial fitting.
Further optionally, step 1031 includes:
fitting a preset number of adjacent most-valued coordinates in the most-valued coordinates corresponding to each propagation distance in sequence to obtain a corresponding fitting straight line set; and determining a target fitting straight line in the fitting straight line set, wherein the residual error from the most-valued coordinate corresponding to each propagation distance to the target fitting straight line is minimum.
The preset number is a positive integer and is smaller than the number of the most significant coordinates corresponding to each propagation distance. Take an actual scene as an example: assuming that 10 most-valued coordinates are obtained based on an adaptive technique, setting the number to be 5, correspondingly, for the 10 most-valued coordinates, sequentially selecting 5 adjacent coordinates in the most-valued coordinates to perform linear fitting (for example, fitting based on a least square method), finally selecting a fitting straight line with the minimum residual error of the 10 most-valued coordinates as a target fitting straight line, and obtaining a tissue slope parameter of a position to be measured according to the slope of the target fitting straight line.
Through the embodiment, after the most-valued coordinates corresponding to different propagation distances are obtained, a certain number of the most-valued coordinates are sequentially selected to be fitted to obtain a plurality of fitting straight lines, an optimal slope parameter of the position to be measured is determined from the plurality of fitting straight lines, the most-valued coordinates with large errors can be removed, and the accuracy and the reliability of slope parameter extraction are further improved.
Subsequent integration with elastography scenes as an example: after the speed value of the shear wave at the position to be measured is determined according to the slope parameter of the position to be measured, the hardness value of the tissue can be obtained through various methods based on the speed value. Optionally, the hardness value of the tissue may be finally obtained according to a formula for obtaining the young's modulus, and after step 103, the method may further include:
determining the speed value of the shear wave at the position to be measured according to the slope parameter of the position to be measured; and calculating to obtain the hardness value of the tissue to be detected at the position to be detected by utilizing a Young modulus formula.
Wherein the Young's modulus formula is as follows: e =3 ρ V S 2 E is the hardness value, rho is the density of the tissue to be measured, V S The value of the shear wave velocity at the location to be measured, i.e. the tissue slope parameter at the location to be measured.
Through the embodiment, the hardness value of the tissue to be detected at the position to be detected can be accurately and quickly obtained.
According to the slope parameter extraction method provided by the embodiment, the most-valued coordinates corresponding to each propagation distance are obtained based on the variable propagated by the test signal along the preset direction at the position to be tested along with time, and the slope parameter of the position to be tested is obtained through fitting.
Optionally, in order to further improve the accuracy of the slope parameter, optimization processing and detection screening may be performed on the most-valued coordinate before fitting.
In an implementation manner, in order to further improve the accuracy of the slope parameter, before fitting, the found most-valued coordinate may be detected based on the number of the variable values and the most-valued coordinate, accordingly, as shown in fig. 2, fig. 2 is a schematic flow chart of a slope parameter extraction method provided in the second embodiment of the present application, and on the basis of the first embodiment, before step 103, the method may further include:
step 201, performing zero crossing point positioning processing on the most significant coordinates corresponding to each propagation distance.
Optionally, step 201 may specifically include:
sequentially judging whether the product of variables corresponding to two adjacent most significant coordinates in the most significant coordinates corresponding to each propagation distance is less than 0;
if the propagation distance is smaller than 0, judging whether the propagation distance corresponding to the variable smaller than 0 is smaller than a first preset distance;
and if the propagation distance corresponding to the variable smaller than 0 is smaller than the first preset distance, removing two adjacent most-valued coordinates and all previous most-valued coordinates of which the product of the corresponding variables is smaller than 0.
Taking the actual scene as an example: when the most significant coordinate is found, cross-stripes may occur (for example, in the signal propagation diagram, assuming that the maximum coordinate corresponds to a first stripe and the minimum coordinate corresponds to a second stripe, when the data is poor, the adjacent first stripe and second stripe may correspond to the same most significant coordinate), and this may cause the final result to have a very large error. In contrast, after obtaining each of the most significant coordinates, first, it is determined whether the products of the variable values corresponding to the adjacent most significant coordinates in each of the most significant coordinates are all greater than 0, and if all of the products are greater than 0, the above-mentioned cross-stripe situation can be eliminated, which indicates that the current most significant coordinates are all valid. And further, judging whether the number of the effective most-valued coordinates meets the requirement of fitting, namely whether the number of the effective most-valued coordinates is not less than a first threshold value, and if so, fitting to obtain the tissue slope parameter of the position to be measured according to the most-valued coordinates.
In practical applications, if the number of the effective maximum coordinates does not satisfy the requirement of the linear fitting, each maximum coordinate needs to be searched again, and accordingly, on the basis of the second embodiment, after the step 201, the method may further include:
if the number of the most significant coordinates corresponding to each propagation distance is smaller than the first threshold, the most significant coordinates corresponding to each propagation distance are removed, and the step 102 is executed.
Taking the actual scene as an example: after the most-valued coordinates are obtained, the situation of crossing stripes is eliminated by judging whether the products of variable values corresponding to adjacent most-valued coordinates in each most-valued coordinate are all larger than 0, then judging whether the number of the current most-valued coordinates meets the requirement of fitting, if not, clearing the currently obtained most-valued coordinates, and obtaining the most-valued coordinates again.
The first threshold may be set according to the fitting accuracy, for example, set to 8. Also, when the maximum value coordinates include the maximum value coordinates and the minimum value coordinates, the above operations performed for the maximum value coordinates and the minimum value coordinates in the present embodiment are performed independently of each other.
In practical applications, the above-mentioned cross-stripe detection manner may be various, for example, after all the maximum coordinates are obtained, it may be detected whether the products of the variable values of the adjacent maximum coordinates are all greater than 0, or it may be detected whether the product of the maximum coordinate and the variable value of the adjacent coordinate is greater than 0 every time one maximum coordinate is obtained in the process of obtaining the maximum coordinates, in short, as long as the products of the finally detected variable values of the adjacent maximum coordinates are all greater than 0, the steps of this embodiment cover the above-mentioned detection manners, and are not limited.
According to the slope parameter extraction method provided by the embodiment, after the most significant coordinate is obtained, cross-fringe detection is performed on the basis of the variable value and the number of the most significant coordinate, and then the slope parameter value of the tissue is obtained through fitting, so that errors caused by cross-fringe can be eliminated, unnecessary processing is avoided, and the accuracy and the efficiency of slope parameter extraction are further improved.
In another embodiment, as shown in fig. 3, fig. 3 is a schematic flow chart of a slope parameter extraction method provided in the third embodiment of the present application, and on the basis of the first embodiment or the second embodiment, before step 103, the method may further include:
and 301, eliminating abnormal maximum coordinates meeting preset conditions.
Optionally, the found most-significant coordinate may be detected based on the relative position of each most-significant coordinate. Correspondingly, on the basis of the third embodiment, step 301 may specifically include:
detecting whether the abscissa of the most-valued coordinate corresponding to M continuous adjacent propagation distances including the initial propagation distance is the same, and if so, deleting the M most-valued coordinates;
detecting whether the abscissa of the most-valued coordinate corresponding to N continuous adjacent propagation distances including the end propagation distance is the same, and if the abscissa of the most-valued coordinate is the same, deleting the N most-valued coordinates;
detecting the most significant coordinates corresponding to the propagation distances in the propagation distances except the initial propagation distance and the end propagation distance, and if the abscissa of the most significant coordinates corresponding to K continuous adjacent propagation distances is the same, only keeping the K' th most significant coordinate; the relationship of K 'and K is subject to practical experience, e.g., when K =2K, K' = K; when K =2k +1, K' = K +1; wherein M, N and k are both positive integers.
Assume that M and N take 3, for example, with an actual scenario: correspondingly, after obtaining each maximum coordinate, detecting whether at least 3 continuous adjacent maximum coordinates exist in the starting position and the ending position, wherein the time coordinate values of the maximum coordinates are the same (assuming that the horizontal axis is a time axis, namely the horizontal axis is the same), if no maximum coordinate exists, no processing is performed, and if yes, the maximum coordinates are eliminated. For example, if the start position or the end position has 4 consecutive nearest coordinates that are adjacent to each other and have the same time coordinate value, the 4 nearest coordinates are deleted.
Still by way of example with a real scenario: after obtaining each maximum coordinate, detecting each maximum coordinate of the non-starting position and the non-ending position, searching the maximum coordinates which are continuously adjacent and have the same time coordinate value, if the number of the maximum coordinates is 4, at the moment, K is even 4,k is 2, keeping the 2 nd maximum coordinate and deleting the rest maximum coordinates, if the number of the maximum coordinates is 5, at the moment, K is odd 5,k is 2, keeping the 3 rd maximum coordinate and deleting the rest maximum coordinates.
In practical application, after the processing is performed, the slope parameter of the position to be measured can be obtained based on a fitting method according to the current most-valued coordinate. Also, when the maximum value coordinates include the maximum value coordinates and the minimum value coordinates, the above operations performed for the maximum value coordinates and the minimum value coordinates in the present embodiment are performed independently of each other.
It is to be understood that, the above-mentioned steps for the maximum coordinates at the starting position, the ending position and the non-starting and ending position may be executed in sequence, including but not limited to: the execution is performed simultaneously or first, and this embodiment is only an exemplary embodiment and does not limit the execution order.
According to the slope parameter extraction method provided by the embodiment, after the most-valued coordinates corresponding to different propagation distances are obtained, filtering and screening are performed on the basis of the relative position of each most-valued coordinate, and then the slope parameter value is obtained through fitting, so that the most-valued coordinate with a large error can be removed, and the accuracy and reliability of tissue slope parameter extraction are further improved.
Optionally, in order to further improve the accuracy of the slope parameter, before the fitting, the detection may be performed based on a relative distance between the most significant coordinates, and correspondingly, on the basis of the third embodiment, the step 301 may specifically include:
calculating the difference V between the abscissa of the maximum coordinate Aj and the abscissa of the maximum coordinate Aj-1 j Wherein j is 3 to x in sequence, and x is a positive integer which is greater than 3 and less than the number of each propagation distance;
if the difference value V j If the maximum value is greater than the preset lower limit value, calculating the maximum value coordinate A 3 To the maximum coordinate A x Average value of absolute value of difference between abscissa of all adjacent two most significant coordinates;
if the average value is smaller than a preset upper limit value, judging the most valued coordinate A j Whether the corresponding propagation distance is smaller than a second preset distance or not;
if the propagation distance corresponding to the maximum coordinate Aj is smaller than the second preset distance, clearing the maximum coordinate Aj and the previous maximum coordinate in a maximum coordinate set { A3,. Aj,. Ax };
if the propagation distance corresponding to the maximum coordinate Aj is greater than the second preset distance, the maximum coordinate Aj and the subsequent maximum coordinate thereof are eliminated from the maximum coordinate set { A3., aj., ax }.
Taking an actual scene as an example: in the process of searching the maximum coordinate, the situation of stripe translation may also occur, for this reason, after each maximum coordinate is obtained, the distance in the horizontal axis direction between each adjacent maximum coordinate is calculated, if the distance is suddenly increased, the stripe translation may occur, and further, the maximum coordinate before the stripe translation is eliminated, so that the accuracy of the final result is prevented from being influenced.
Wherein the second preset distance may be set according to the accuracy of the calculation. The present embodiment is not limited thereto. Also, when the maximum value coordinates include the maximum value coordinates and the minimum value coordinates, the above operations performed for the maximum value coordinates and the minimum value coordinates in the present embodiment are performed independently of each other.
According to the slope parameter extraction method provided by the embodiment, after the most-valued coordinates corresponding to different depths are obtained, stripe translation detection is performed on the basis of the relative distance between the most-valued coordinates, and then the slope parameter value of the tissue is obtained through fitting, so that errors caused by stripe translation can be eliminated, and the accuracy and reliability of slope parameter extraction are further improved.
It can be understood that the above detection schemes for improving the accuracy of the final result may be implemented independently or in combination, for example, after obtaining the maximum coordinate, filtering, screening, cross-stripe detection and stripe translation detection may be performed respectively, and the execution sequence may be set arbitrarily.
Fig. 4 is a schematic flow chart of a slope parameter extraction method provided in a fourth embodiment of the present application, and as shown in fig. 4, on the basis of any one of the foregoing embodiments, the most significant coordinate includes a maximum value coordinate and a minimum value coordinate; correspondingly, step 103 may specifically include:
step 401, according to the maximum value coordinates corresponding to each propagation distance and the minimum value coordinates corresponding to each propagation distance, respectively fitting to obtain a first target slope corresponding to the maximum value coordinates and a second target slope corresponding to the minimum value coordinates;
step 402, determining a slope parameter of the position to be measured according to the first target slope and the second target slope.
In practical application, based on the propagation condition of the shear wave, a plurality of fringes may appear in the signal propagation diagram, so that a slope parameter can be obtained based on the plurality of fringes, and a more accurate result is selected from the slope parameter, thereby further improving the accuracy of the final result.
Taking the actual scene as an example: in this embodiment, the maximum coordinates include a maximum coordinate and a minimum coordinate, that is, a series of maximum coordinates and a series of minimum coordinates are obtained by performing step 102, a first target slope is obtained by fitting according to each maximum coordinate, a second target slope is obtained by fitting according to each minimum coordinate, and then, based on the respective corresponding stripes of the maximum coordinates and the minimum coordinates, a more accurate slope parameter is selected from the first target slope and the second target slope.
In an embodiment, step 402 may specifically include: and selecting one target slope from the first target slope and the second target slope as a slope parameter of the position to be measured.
Optionally, the slope of the fitted straight line corresponding to the fringe with the larger propagation distance coordinate may be selected as the final result, that is, assuming that the vertical axis of the signal propagation diagram represents the propagation distance and the vertical axis extends from top to bottom with the larger propagation distance, the slope of the fitted straight line obtained from the most significant coordinate corresponding to the relatively lower fringe is selected as the final slope parameter.
In another embodiment, step 402 may specifically include: and taking the average value of the first target slope and the second target slope as a slope parameter of the position to be measured.
Optionally, the accuracy of the final result may be further strengthened by measuring multiple times, and a fifth embodiment of the present application provides a slope parameter extraction method, where on the basis of any embodiment, the step 102 is performed multiple times to obtain multiple sets of maximum coordinates.
Specifically, for example, the step 102 may be repeatedly performed T times to obtain the most significant coordinates of the T measurements. Where T is a positive integer, for example, T is 10, i.e., 10 measurements are taken. Likewise, the most significant coordinates may include a maximum value coordinate and/or a minimum value coordinate. When the maximum value coordinates include the maximum value coordinates and the minimum value coordinates, the above operations performed for the maximum value coordinates and the minimum value coordinates in the present embodiment are performed independently of each other. For example, assuming T is 10, by performing 102, a set of maximum and minimum coordinates may be obtained for each measurement, and finally 10 sets of maximum and minimum coordinates may be obtained.
After obtaining the maximum coordinates of the T measurements, taking 10 sets of maximum coordinates obtained as an example, according to the 10 sets of maximum coordinates, 10 target slopes, that is, a first target slope set, may be obtained by fitting, optionally, a median value of the set may be used as a first target slope corresponding to the maximum coordinate, and similarly, the above processing may be performed on the minimum coordinate, so as to finally obtain a first target slope corresponding to the maximum coordinate and a second target slope corresponding to the minimum coordinate.
In addition, as exemplified with reference to the fourth embodiment, on the basis of the fourth embodiment, the step 102 is performed multiple times to obtain multiple sets of maximum coordinates; correspondingly, step 401 may specifically include:
according to the multiple groups of the most-valued coordinates, respectively fitting to obtain a first target slope set corresponding to the maximum value coordinates and a second target slope set corresponding to the minimum value coordinates;
and calculating the median of the first target slope set to obtain the first target slope, and calculating the median of the second target slope set to obtain the second target slope.
In practical application, in a tissue elastography scene, after obtaining a first target slope and a second target slope, the positions of respective corresponding stripes may be referred to, and a series of constraints on a target slope set are combined to further select a more accurate result, and correspondingly, step 402 may specifically include:
and determining the tissue slope parameter of the position to be detected according to the relative position relationship of the first stripe and the second stripe and by combining a preset condition.
Specifically, the conditions include: when saidIf the depth (propagation distance) of the first stripe is larger, if the first median of the first target slope set is not greater than the second threshold and the first target slope A is larger max And a second target slope A min Belonging to the same histopathological stage and having a first relative deviation of the first target slope set smaller than a second relative deviation of the second target slope set, or if the first median value is not greater than the second threshold value and A max And A min Not belonging to the same histopathology stage, wherein the first relative deviation is smaller than a preset third threshold, the ratio of the first difference between the first target slope set and the second difference between the second target slope set and the first target slope set is smaller than a preset fourth threshold, and the absolute value of the difference between the first median and the second median of the second target slope set is not smaller than a preset fifth threshold, and then the tissue slope parameter of the position to be detected is determined to be the first target slope A max The relative deviation of the target slope set is the ratio of the quartile difference to the median value of the target slope set;
when the depth of the first stripe is larger, if the first median is not larger than the second threshold, amax and Amin belong to the same histopathology stage, and the first relative deviation is larger than the second relative deviation, or if the first median is larger than the second threshold, and the second relative deviation is smaller than the third threshold, determining that the tissue slope parameter of the position to be detected is the second target slope A min ；
When the depth of the second stripe is larger, if the second median is not greater than the second threshold and A max And A min Belonging to the same histopathological stage and the first relative deviation is greater than the second relative deviation, or if the second median is not greater than the second threshold and A max And A min If the measured tissue pathological stages do not belong to the same histopathological stage, the second relative deviation is smaller than the third threshold, the ratio of the second difference to the first difference is smaller than the fourth threshold, and the absolute value of the difference between the second median and the first median is not smaller than the fifth threshold, determining that the measured tissue pathological stages do not belong to the same histopathological stage, and the ratio of the second difference to the first difference is smaller than the fourth threshold, and the absolute value of the difference between the second median and the first median is not smaller than the fifth thresholdThe tissue slope parameter of the position is the second target slope A min ；
When the depth of the second stripe is larger, if the second median is not greater than the second threshold and A max And A min Belonging to the same histopathological stage and having a first relative deviation less than a second relative deviation, or if the second median value is not greater than the second threshold value and A max And A min Not belonging to the same histopathology stage, and the second relative deviation is not less than the third threshold, or the ratio of the second difference to the first difference is not less than the fourth threshold, or the absolute value of the difference between the second median and the first median is less than the fifth threshold, or if the second median is greater than the second threshold and the first relative deviation is less than the third threshold, determining the tissue slope parameter of the position to be detected as the first target slope A max 。
Each threshold may be set according to the accuracy, for example, the second threshold is 14, the third threshold is 0.3, the fourth threshold is 2, and the fifth threshold is 1.5. The histopathological stages correspond to different hardness value ranges, and the actual application can refer to the tissue hardness value and a control reference standard of the histopathological stages.
Optionally, since a measurement result with a large error may occur in the measurement process, the accuracy of the final result is further improved. Correspondingly, a sixth embodiment of the present application provides a slope parameter extraction method, and on the basis of the fifth embodiment, the method may further include:
and according to a preset judgment condition, removing invalid most value coordinate groups from the multiple groups of most value coordinates obtained by the multiple executions.
Optionally, the elimination scheme may include: for a first target slope A obtained in the ith measurement max-i And a second target slope A min-i If A is max-i And A min-i If the absolute value of the difference is greater than the preset sixth threshold, the measurement A is carried out max-i And A min-i Marking as noneAnd (5) measuring the effect.
Specifically, in each measurement process, a series of maximum value coordinates and a series of minimum value coordinates can be obtained, correspondingly, a first target slope and a second target slope under the current measurement can be obtained, based on the two target slopes, whether the current measurement is valid can be judged, if the difference between the two target slope values is too large, the current measurement error is large, namely the current measurement is invalid, and all the maximum value coordinates obtained by the current measurement are rejected.
Further, if the number of invalid measurements in the T measurements is too many, accuracy of a final result may be affected, and for this reason, if the number of invalid measurements in the T measurements is too many, the T measurement results are cleared, and the T measurements are re-measured to obtain a corresponding target slope set, and accordingly, after step 501, the method may further include:
if the number of times of invalid measurement in the first target slope set or the second target slope set is greater than a preset seventh threshold, the first target slope set and the second target slope set are cleared accordingly, and the step 102 is executed again.
For example, if T is 10, and if at least 5 measurements out of 10 measurements are invalid, the 10 measurements are cancelled and re-measured 10 times. By the method and the device, the influence of invalid measurement on the final result can be avoided, and the accuracy and the reliability of the finally obtained slope parameter are improved.
Optionally, in order to further improve the accuracy of the final result, the signal propagation diagram may be filtered, a seventh embodiment of the present application provides a slope parameter extraction method, and on the basis of the fifth embodiment, the method may further include:
band pass filtering the variable.
Alternatively, the method of performing bandpass filtering may be least square based bandpass filtering. In practical applications, when the external interference is large, the quality of the filtered strain data is still poor, and if the filtered result is directly selected, a large error may be caused, and for this, the step 102 may specifically include:
before and after filtering, repeating the step of 102 times respectively to obtain the most-valued coordinates of each propagation distance before and after filtering;
correspondingly, in the fifth embodiment in combination with the fourth embodiment, the obtaining, by fitting respectively according to the multiple sets of the most significant coordinates, a first target slope set corresponding to the maximum coordinate and a second target slope set corresponding to the minimum coordinate may specifically include:
according to the coordinates of the maximum values corresponding to the T times of measurement before filtering, fitting to obtain a first slope set to be selected { B } max-1 ,..,B max-i ,..,B max-T }；
According to the coordinates of each minimum value corresponding to the T times of measurement before filtering, fitting to obtain a second slope set { B to be selected min-1 ,..,B min-i ,..,B min-T }；
According to the coordinates of the maximum values corresponding to the T times of measurement after filtering, fitting to obtain a third candidate slope set { C max-1 ,..,C max-i ,..,C max-T }；
According to the coordinates of each minimum value corresponding to the T times of measurement after filtering, fitting to obtain a fourth candidate slope set { C min-1 ,..,C min-i ,..,C min-T }；
If the third relative deviation of a third candidate slope set or the fourth relative deviation of a fourth candidate slope set is not greater than the third threshold, respectively using the obtained third candidate slope set and the obtained fourth candidate slope set as the first target slope set and the second target slope set, otherwise, respectively using the obtained first candidate slope set and the obtained second candidate slope set as the first target slope set and the second target slope set.
Optionally, the maximum value coordinates or the minimum value coordinates may be fitted by a least square method, a linear fitting method, a polynomial fitting method, or the like.
For example, based on a signal propagation diagram, performing band-pass filtering according to the frequency of a test signal, measuring T-times minimum coordinates for the signal propagation diagram before and after filtering, and obtaining T-group maximum coordinates and T-group minimum coordinates before and after filtering. According to the four groups of most-valued coordinates, a first to-be-selected slope set corresponding to the maximum value coordinate before filtering, a second to-be-selected slope set corresponding to the minimum value coordinate before filtering, a third to-be-selected slope set corresponding to the maximum value coordinate after filtering, and a fourth to-be-selected slope set corresponding to the minimum value coordinate after filtering are obtained through fitting, wherein each to-be-selected slope set comprises T slopes. And judging whether the result before filtering or the result after filtering is reserved according to the relative deviation of the two slope sets to be selected after filtering, and then obtaining the final slope parameter from the reserved result based on the scheme.
The slope parameter extraction device provided by the embodiment obtains the final slope parameter based on the multiple measurement results performed before and after filtering through multiple measurements, filtering and the like on the basis of searching the most-valued coordinate, and further improves the accuracy and reliability of slope parameter extraction.
Fig. 5 is a schematic structural diagram of an eighth slope parameter extraction apparatus according to the present application, as shown in fig. 5, the slope parameter extraction apparatus includes:
an obtaining module 51, configured to obtain a variable that a test signal propagates along a preset direction at a to-be-tested position along with time;
a determining module 52, configured to determine a coordinate where a maximum value of a variable corresponding to each propagation distance in the preset direction is located, and obtain a maximum value coordinate corresponding to each propagation distance;
and the processing module 53 is configured to fit and process the most significant coordinates corresponding to the propagation distances to obtain a slope parameter of the position to be measured.
The form of the test signal may be various, for example, acoustic wave, shear wave, etc. The variable may be any variable reflecting the characteristics of the fluctuation. Optionally, on the basis of the embodiment shown in fig. 5, the determining module may include: the generating unit is used for generating a signal propagation diagram after acquiring a variable of the test signal propagating along a preset direction along with time at a position to be tested; the determining unit is used for determining the initial most value coordinate from the initial region to be measured of the signal propagation diagram and taking the initial most value coordinate as the current most value coordinate; and the searching unit is used for searching the most-valued coordinate corresponding to the next propagation distance along the time direction in the signal propagation diagram from the corresponding position of the current most-valued coordinate in the next propagation distance, updating the most-valued coordinate into the current most-valued coordinate, and so on until the most-valued coordinate corresponding to each propagation distance is searched.
In this embodiment, the maximum coordinate may be a maximum coordinate, a minimum coordinate, a maximum coordinate, and a minimum coordinate. According to the embodiment, the coordinate point with better effect can be obtained for fitting, so that more accurate slope parameters can be obtained.
Optionally, on the basis of any one of the foregoing embodiments, the processing module is specifically configured to fit a preset number of adjacent maximum coordinates in the maximum coordinates corresponding to each propagation distance in sequence, so as to obtain a corresponding fitted straight line set; and determining a target fitting straight line in the fitting straight line set, wherein the residual error from the most-valued coordinate corresponding to each propagation distance to the target fitting straight line is minimum. Through the embodiment, the slope parameter of the position to be measured can be accurately obtained through linear fitting based on least square according to the selected most-valued coordinate.
Subsequent integration with elastography scenes as an example: the processing module can be further used for determining a speed value of the shear wave at the position to be detected according to the slope parameter of the position to be detected; and calculating to obtain the hardness value of the tissue to be detected at the position to be detected by utilizing a Young modulus formula. Wherein the Young's modulus formula is as follows: e =3 ρ V S 2 E is the hardness value, rho is the density of the tissue to be measured, V S The value of the speed of the shear wave at the position to be measured, i.e. the tissue slope parameter of the position to be measured. Through the embodiment, the hardness value of the tissue to be detected at the position to be detected can be accurately and quickly obtained.
The slope parameter extraction device provided by this embodiment obtains the most significant coordinates corresponding to each propagation distance based on the variable propagated along the preset direction along with time at the position to be tested by the test signal, and obtains the slope parameter of the position to be tested by fitting.
Optionally, in order to further improve the accuracy of the slope parameter, optimization processing and detection screening may be performed on the most-valued coordinate before fitting.
In an embodiment, in order to further improve the accuracy of the slope parameter, before the fitting, the found most-significant coordinate may be detected based on the variable value and the number of the most-significant coordinates, and accordingly, on the basis of the eighth embodiment, the apparatus further includes:
and the first optimization module is used for positioning the zero crossing point of the coordinate before the processing module fits the most-valued coordinate corresponding to each appointed depth.
Optionally, the first optimization module may be specifically configured to sequentially determine whether a product of variables corresponding to two adjacent most significant coordinates in the most significant coordinates corresponding to each propagation distance is less than 0; if the propagation distance is smaller than 0, judging whether the propagation distance corresponding to the variable smaller than 0 is smaller than a first preset distance; and if the propagation distance corresponding to the variable smaller than 0 is smaller than the first preset distance, removing two adjacent most-valued coordinates and all previous most-valued coordinates of which the product of the corresponding variables is smaller than 0.
In practical applications, if the number of the effective maximum coordinates does not satisfy the requirement of linear fitting, each maximum coordinate needs to be searched for in a self-adaptive manner again, and correspondingly, the first optimization module may be further configured to clear the maximum coordinates corresponding to each propagation distance if the number of the maximum coordinates corresponding to each propagation distance is smaller than a first threshold, and return to the execution 102.
In another embodiment, the apparatus further comprises: and the second optimization module is used for eliminating abnormal coordinates meeting preset conditions before the processing module performs fitting processing on the most-valued coordinates corresponding to each appointed depth.
Optionally, the second optimization module may be specifically configured to detect whether abscissa coordinates of the most significant coordinates corresponding to M consecutive adjacent propagation distances, including the initial propagation distance, are all the same, and if all the abscissa coordinates are the same, delete the M most significant coordinates; detecting whether the abscissa of the most-valued coordinate corresponding to N continuous adjacent propagation distances including the end propagation distance is the same, and if so, deleting the N most-valued coordinates; detecting the most significant coordinates corresponding to the propagation distances in the propagation distances except the initial propagation distance and the end propagation distance, and if the abscissa of the most significant coordinates corresponding to K continuous adjacent propagation distances is the same, only keeping the K' th most significant coordinate; the relationship of K 'and K is subject to practical experience, e.g., when K =2K, K' = K; when K =2k +1, K' = K +1; wherein M, N and k are both positive integers.
Optionally, the second optimization module may be further configured to calculate a maximum coordinate a j Abscissa and the most significant coordinate A of j-1 Is a difference V of the abscissa j Wherein j is 3 to x in sequence, and x is a positive integer which is greater than 3 and less than the number of each propagation distance; if the difference value V j If the maximum value is greater than the preset lower limit value, calculating the maximum value coordinate A 3 To the maximum coordinate A x Average value of absolute value of difference between abscissa of all adjacent two most significant coordinates; if the average value is smaller than a preset upper limit value, judging the most valued coordinate A j Whether the corresponding propagation distance is smaller than a second preset distance; if the maximum coordinate A j If the corresponding propagation distance is less than the second preset distance, then the maximum coordinate set { A }is obtained 3 ,..,A j ,..,A x Removing the maximum coordinate A j And its previous most-valued coordinates; if the maximum coordinate A j If the corresponding propagation distance is greater than the second preset distance, the maximum coordinate set { A }is obtained 3 ,..,A j ,..,A x Removing the maximum coordinate A j And the most significant coordinates after it.
On the basis of any one of the foregoing embodiments, the most significant coordinates include a maximum value coordinate and a minimum value coordinate; correspondingly, the processing module comprises: the fitting unit is used for respectively fitting and obtaining a first target slope corresponding to the maximum value coordinate and a second target slope corresponding to the minimum value coordinate according to the maximum value coordinate corresponding to each propagation distance and the minimum value coordinate corresponding to each propagation distance; and the processing unit is used for determining the slope parameter of the position to be measured according to the first target slope and the second target slope.
The processing unit is specifically configured to select a target slope from the first target slope and the second target slope as a slope parameter of the position to be measured; or, the processing unit is specifically configured to use an average value of the first target slope and the second target slope as a slope parameter of the to-be-measured position.
Optionally, on the basis of any embodiment, the step of obtaining the most significant coordinates corresponding to each propagation distance is performed multiple times to obtain multiple sets of most significant coordinates.
In one embodiment, the fitting unit comprises: the fitting subunit is used for respectively fitting and obtaining a first target slope set corresponding to the maximum value coordinate and a second target slope set corresponding to the minimum value coordinate according to the multiple groups of the maximum value coordinates; and the calculating subunit is used for calculating a median of the first target slope set to obtain the first target slope, and calculating a median of the second target slope set to obtain the second target slope.
In practical application, the processing unit may be specifically configured to determine the tissue slope parameter of the to-be-detected position according to the relative position relationship between the first stripe and the second stripe, in combination with a preset condition. Specifically, the conditions include: when the depth (propagation distance) of the first stripe is larger, if the first median of the first target slope set is not greater than the preset second threshold and the first target slope A is larger than the preset second threshold max And a second target slope A min Belonging to the same histopathology stage and having a first relative deviation of a first target slope set smaller than a second relative deviation of a second target slope set, or if the first median is not greater than the second threshold and A max And A min Not belonging to the same histopathological stage and the first relative deviation is smaller than a preset third threshold and the first targetDetermining that the tissue slope parameter of the position to be detected is the first target slope A if the ratio of the first difference of the slopes and the second difference of the second target slope is smaller than a preset fourth threshold and the absolute value of the difference between the first median and the second median of the second target slope is not smaller than a preset fifth threshold max The relative deviation of the target slope set is the ratio of the quartile difference to the median value of the target slope set; when the depth of the first stripe is larger, if the first median is not larger than the second threshold and A max And A min Belonging to the same histopathology stage and the first relative deviation is greater than the second relative deviation, or if the first median is greater than the second threshold and the second relative deviation is less than the third threshold, determining the tissue slope parameter of the position to be detected as the second target slope A min (ii) a When the depth of the second stripe is larger, if the second median is not greater than the second threshold and A max And A min Belonging to the same histopathological stage and the first relative deviation is greater than the second relative deviation, or if the second median is not greater than the second threshold and A max And A min Not belonging to the same histopathology stage, wherein the second relative deviation is smaller than the third threshold, the ratio of the second difference to the first difference is smaller than the fourth threshold, and the absolute value of the difference between the second median and the first median is not smaller than the fifth threshold, then the tissue slope parameter of the position to be detected is determined to be the second target slope A min (ii) a When the depth of the second stripe is larger, if the second median is not greater than the second threshold and A max And A min Belonging to the same histopathological stage and the first relative deviation is smaller than the second relative deviation, or if the second median is not greater than the second threshold and A max And A min Not belonging to the same histopathological stage and the second relative deviation is not less than the third threshold or the ratio of the second differential to the first differential is not less than the fourth threshold or the second median to the first differentialThe absolute value of the difference between the first median values is smaller than the fifth threshold, or if the second median value is larger than the second threshold and the first relative deviation is smaller than the third threshold, the tissue slope parameter of the position to be detected is determined to be the first target slope A max 。
Optionally, since a measurement result with a large error may occur in the measurement process, the accuracy of the final result is further improved. Each measurement can be screened, and correspondingly, the device further comprises:
and the third optimization module is used for eliminating invalid maximum value coordinate groups from the multiple groups of maximum value coordinates obtained by the multiple executions according to a preset judgment condition.
Optionally, the third optimization module elimination scheme may include: for the first target slope A obtained in the ith measurement max-i And a second target slope A min-i If A is max-i And A min-i If the absolute value of the difference is greater than the preset sixth threshold, the measurement A is carried out max-i And A min-i Marked as invalid measurement.
Further, the third optimization module may be further configured to, if the number of times of the invalid measurement in the first target slope set or the second target slope set is greater than a preset seventh threshold, correspondingly clear the first target slope set and the second target slope set, and return to step 102.
Optionally, in order to further improve the accuracy of the final result, the signal propagation diagram may be filtered, and on the basis of the fifth embodiment, the apparatus may further include: and the filtering module is used for carrying out band-pass filtering on the signal propagation diagram.
For this, the determining module may be specifically configured to repeatedly execute the step 102T times before filtering and after filtering, and obtain the most significant coordinates of each depth before filtering and after filtering.
Optionally, the processing module may be specifically configured to obtain a first to-be-selected slope set { B ] by fitting according to each maximum value coordinate corresponding to T times of measurement before filtering max-1 ,..,B max-i ,..,B max-T }; according to the coordinates of each minimum value corresponding to the T times of measurement before filtering, fitting to obtain a second slope set { B to be selected min-1 ,..,B min-i ,..,B min-T }; according to the coordinates of each maximum value corresponding to the T times of measurement after filtering, fitting to obtain a third candidate slope set { C max-1 ,..,C max-i ,..,C max-T }; according to the coordinates of each minimum value corresponding to the T times of measurement after filtering, fitting to obtain a fourth candidate slope set { C min-1 ,..,C min-i ,..,C min-T }; if the third relative deviation of a third candidate slope set or the fourth relative deviation of a fourth candidate slope set is not greater than the third threshold, respectively using the obtained third candidate slope set and the obtained fourth candidate slope set as the first target slope set and the second target slope set, otherwise, respectively using the obtained first candidate slope set and the obtained second candidate slope set as the first target slope set and the second target slope set.
It can be clearly understood by those skilled in the art that, for convenience and simplicity of description, the specific working process of the apparatus described above may refer to the corresponding process in the foregoing method embodiment, and details are not described herein again.
The embodiment of the present application further provides a slope parameter extraction device, which includes: at least one processor and a memory; the memory stores computer-executable instructions; the at least one processor executes computer-executable instructions stored by the memory to perform the method as previously described.
An embodiment of the present application further provides a computer-readable storage medium, where a computer program is stored in the computer-readable storage medium, and when the computer program is executed, the computer program implements the method as described above.
Those of ordinary skill in the art will understand that: all or a portion of the steps of implementing the above-described method embodiments may be performed by hardware associated with program instructions. The foregoing program may be stored in a computer-readable storage medium. When executed, the program performs steps comprising the method embodiments described above; and the aforementioned storage medium includes: various media that can store program codes, such as ROM, RAM, magnetic or optical disks.
Finally, it should be noted that: the above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art will understand that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present application.

Claims (15)

1. A slope parameter extraction method is characterized by comprising the following steps:
acquiring a variable of a test signal propagating along a preset direction at a position to be tested along with time;
determining the coordinate of the most value of the variable corresponding to each propagation distance in the preset direction, and obtaining the most value coordinate corresponding to each propagation distance;
fitting and processing the most-valued coordinates corresponding to the propagation distances to obtain slope parameters of the position to be measured;
before the fitting process of the maximum coordinates corresponding to the propagation distances, the method further includes:
sequentially judging whether the product of variables corresponding to two adjacent most significant coordinates in the most significant coordinates corresponding to each propagation distance is less than 0;
if the propagation distance is smaller than 0, judging whether the propagation distance corresponding to the variable smaller than 0 is smaller than a first preset distance;
and if the propagation distance corresponding to the variable smaller than 0 is smaller than the first preset distance, removing two adjacent most-valued coordinates and all previous most-valued coordinates of which the product of the corresponding variables is smaller than 0.
2. The method according to claim 1, wherein the determining coordinates of the most significant value of the variable corresponding to each propagation distance in the preset direction to obtain the most significant coordinates corresponding to each propagation distance includes:
acquiring a variable of the test signal transmitted along a preset direction along with time at a position to be tested, and then generating a signal transmission diagram;
determining initial most value coordinates from the initial region to be measured of the signal propagation diagram, and taking the initial most value coordinates as current most value coordinates;
starting from the corresponding position of the current maximum coordinate in the next propagation distance, searching the maximum coordinate corresponding to the next propagation distance in the signal propagation diagram along the time direction, updating the maximum coordinate to the current maximum coordinate, and so on until the maximum coordinate corresponding to each propagation distance in the signal propagation diagram is found.
3. The method according to claim 1, wherein the fitting process of the most-valued coordinates corresponding to the propagation distances to obtain the slope parameter of the position to be measured includes:
fitting the most-valued coordinates corresponding to each propagation distance to obtain a target fitting straight line;
and taking the slope of the target fitting straight line as a slope parameter of the position to be measured.
4. The method according to claim 3, wherein the fitting the most significant coordinates corresponding to the propagation distances to obtain a target fitting straight line comprises:
fitting a preset number of adjacent most-valued coordinates in the most-valued coordinates corresponding to each propagation distance in sequence to obtain a corresponding fitting straight line set;
and determining a target fitting straight line in the fitting straight line set, wherein the residual error from the most-valued coordinate corresponding to each propagation distance to the target fitting straight line is minimum.
5. The method according to any one of claims 1 to 4, wherein before the fitting process of the most-valued coordinates corresponding to the propagation distances, further comprising:
and eliminating abnormal maximum coordinates meeting preset conditions.
6. The method according to claim 5, wherein the eliminating abnormal maximum coordinates meeting a preset condition comprises:
detecting whether the abscissa of the most-valued coordinate corresponding to M continuous adjacent propagation distances including the initial propagation distance is the same, and if so, deleting the M most-valued coordinates; detecting whether the abscissa of the most-valued coordinate corresponding to N continuous adjacent propagation distances including the end propagation distance is the same, and if so, deleting the N most-valued coordinates; detecting the most significant coordinates corresponding to the propagation distances in the propagation distances except the initial propagation distance and the end propagation distance, and if the abscissa of the most significant coordinates corresponding to K continuous adjacent propagation distances is the same, only keeping the K' th most significant coordinate; the relationship between K' and K is: when K =2K, K' = K; when K =2k +1, K' = K +1; wherein M, N and k are both positive integers; alternatively, the first and second electrodes may be,
calculating the difference V between the abscissa of the maximum coordinate Aj and the abscissa of the maximum coordinate Aj-1 j Wherein j is 3 to x in sequence, and x is a positive integer which is greater than 3 and less than the number of each propagation distance; if the difference value V j If the maximum value is greater than the preset lower limit value, calculating the maximum value coordinate A 3 To the maximum coordinate A x Average value of absolute value of difference between abscissa of all adjacent two most significant coordinates; if the average value is smaller than a preset upper limit value, judging the most valued coordinate A j Whether the corresponding propagation distance is smaller than a second preset distance; if the maximum coordinate A j If the corresponding propagation distance is less than the second preset distance, then the maximum coordinate set { A }is obtained 3 ,.. , A j ,.., A x Removing the most significant coordinate A from the j And its previous most-valued coordinates; if the maximum coordinate A j If the corresponding propagation distance is greater than the second preset distance, the maximum coordinate set { A }is obtained 3 ,.. , A j ,.., A x Removing the maximum coordinate A j Andits following most significant coordinate.
7. The method of claim 1, wherein the most significant coordinate comprises a maximum value coordinate and a minimum value coordinate; the fitting process is performed on the most-valued coordinates corresponding to the propagation distances to obtain slope parameters of the position to be measured, and the method comprises the following steps:
respectively fitting to obtain a first target slope corresponding to the maximum value coordinate and a second target slope corresponding to the minimum value coordinate according to the maximum value coordinate corresponding to each propagation distance and the minimum value coordinate corresponding to each propagation distance;
and determining a slope parameter of the position to be detected according to the first target slope and the second target slope.
8. The method of claim 7, wherein determining the slope parameter of the location to be measured from the first target slope and the second target slope comprises:
selecting a target slope from the first target slope and the second target slope as a slope parameter of the position to be detected; alternatively, the first and second liquid crystal display panels may be,
and taking the average value of the first target slope and the second target slope as a slope parameter of the position to be measured.
9. The method according to claim 7 or 8, wherein the step of obtaining the most significant coordinates corresponding to each propagation distance is performed a plurality of times to obtain a plurality of sets of most significant coordinates;
the respectively fitting to obtain a first target slope corresponding to the maximum value coordinate and a second target slope corresponding to the minimum value coordinate includes:
according to the multiple groups of the most-valued coordinates, respectively fitting to obtain a first target slope set corresponding to the maximum value coordinates and a second target slope set corresponding to the minimum value coordinates;
and calculating the median of the first target slope set to obtain the first target slope, and calculating the median of the second target slope set to obtain the second target slope.
10. The method of claim 9, further comprising:
and according to a preset judgment condition, removing invalid most-valued coordinate groups from the multiple groups of most-valued coordinates obtained by the multiple executions.
11. The method of claim 9, further comprising:
band-pass filtering the variable;
wherein the step of obtaining the most significant coordinates corresponding to each propagation distance is performed a plurality of times to obtain a plurality of sets of most significant coordinates includes:
and respectively repeating the step of obtaining the most value coordinates corresponding to each propagation distance for T times before and after filtering, and obtaining T groups of most value coordinates before and after filtering, wherein T is a positive integer.
12. The method of claim 11, wherein obtaining a first target slope set corresponding to a maximum coordinate and a second target slope set corresponding to a minimum coordinate by fitting respectively according to the plurality of sets of maximum coordinates comprises:
according to the coordinates of the maximum values corresponding to the T times of measurement before filtering, fitting to obtain a first slope set to be selected { Bmax-1., bmax-i., bmax-T };
according to the coordinates of the minimum values corresponding to the T times of measurement before filtering, fitting to obtain a second slope set to be selected { Bmin-1., bmin-i., bmin-T };
according to the coordinates of the maximum values corresponding to the T times of measurement after filtering, fitting to obtain a third candidate slope set { Cmax-1., cmax-i., cmax-T };
according to the coordinates of the minimum values corresponding to the T times of filtered measurement, fitting to obtain a fourth slope set to be selected { Cmin-1., cmin-i., cmin-T };
if the third relative deviation of the third candidate slope set or the fourth relative deviation of the fourth candidate slope set is not greater than a third threshold, the obtained third candidate slope set and the fourth candidate slope set are respectively used as the first target slope set and the second target slope set, otherwise, the obtained first candidate slope set and the second candidate slope set are respectively used as the first target slope set and the second target slope set.
13. A slope parameter extraction device, characterized by comprising:
the acquisition module is used for acquiring a variable of a test signal which is transmitted along a preset direction along with time at a position to be tested;
the determining module is used for determining the coordinate where the most value of the variable corresponding to each propagation distance in the preset direction is located, and obtaining the most value coordinate corresponding to each propagation distance;
the first optimization module is used for sequentially judging whether the product of variables corresponding to two adjacent maximum coordinates in the maximum coordinates corresponding to each propagation distance is less than 0 before fitting the maximum coordinates corresponding to each propagation distance; if the propagation distance is smaller than 0, judging whether the propagation distance corresponding to the variable smaller than 0 is smaller than a first preset distance; if the propagation distance corresponding to the variable smaller than 0 is smaller than the first preset distance, eliminating two adjacent most-valued coordinates and all previous most-valued coordinates of which the product of the corresponding variables is smaller than 0;
and the processing module is used for fitting and processing the most-valued coordinates corresponding to the propagation distances to obtain the slope parameter of the position to be measured.
14. A slope parameter extraction device, characterized by comprising: at least one processor and a memory;
the memory stores computer-executable instructions; the at least one processor executes computer-executable instructions stored by the memory to perform the method of any of claims 1-12.
15. A computer-readable storage medium, characterized in that a computer program is stored in the computer-readable storage medium, which computer program, when executed, implements the method of any one of claims 1-12.
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