Method and device for determining volume of interest VOI

Abstract

The present application discloses a VOI determination method and device, which belongs to the field of medical image processing technology. The VOI determination method includes: obtaining M target point cloud points, where M is a positive integer; determining M projection points of the M target point cloud points on a target projection plane, where the target projection plane is: one of three projection planes, where the three projection planes are mutually perpendicular and the intersection point is the center point of a regular VOI; the target projection plane includes an irregular target projection area; from the M projection points, determining the target projection point located in the target projection area; and determining the target VOI according to the point cloud points corresponding to the target projection point.

Description

Technical Field

[0001] The present application belongs to the field of medical image processing technology, and specifically relates to a VOI determination method and device. Background Art

[0002] Currently, point cloud data corresponding to the outer contour of the human body can be collected through a three-dimensional (3D) camera, and then a regular volume of interest (VOI) containing multiple point cloud data to be registered can be determined through user operation, and finally the point cloud data in the regular VOI can be registered with the point cloud data in the reference template.

[0003] However, since the regular VOI includes a large number of point cloud points that interfere with the registration, the registration accuracy is poor. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide a VOI determination method and device, which can solve the problem of poor accuracy in point cloud registration of point cloud data.

[0005] In a first aspect, an embodiment of the present application provides a VOI determination method, the method comprising: obtaining M target point cloud points, where M is a positive integer; determining M projection points of the M target point cloud points on a target projection plane, the target projection plane being: one of three projection planes, the three projection planes being perpendicular to each other and the intersection of which is the center point of a regular VOI; the target projection plane comprising an irregular target projection area; determining a target projection point located in the target projection area from the M projection points; and determining the target VOI based on the point cloud points corresponding to the target projection points.

[0006] In the second aspect, an embodiment of the present application provides a VOI determination device, and the VOI determination device includes: an acquisition module, a first determination module, a second determination module and a third determination module. Among them, the acquisition module is used to acquire M target point cloud points, and M is a positive integer. The first determination module is used to determine the M projection points on the target projection plane among the M target point cloud points acquired by the acquisition module, and the target projection plane is: one of the three projection planes, and the three projection planes are perpendicular to each other and the intersection point is the center point of the regular VOI; the target projection plane includes an irregular target projection area. The second determination module is used to determine the target projection point located in the target projection area from the M projection points determined by the first determination module. The third determination module is used to determine the target VOI according to the point cloud points corresponding to the target projection points determined by the second determination module.

[0007] In a third aspect, an embodiment of the present application provides a computer device, which includes a processor, a memory, and a program or instruction stored in the memory and executable on the processor, wherein the program or instruction, when executed by the processor, implements the steps of the method described in the first aspect.

[0008] In a fourth aspect, an embodiment of the present application provides a readable storage medium, on which a program or instruction is stored, and when the program or instruction is executed by a processor, the steps of the method described in the first aspect are implemented.

[0009] In a fifth aspect, an embodiment of the present application provides a chip, comprising a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is used to run a program or instruction to implement the method described in the first aspect.

[0010] In an embodiment of the present application, the VOI determination device may first obtain M target point cloud points, and determine M projection points of the M target point cloud points on an irregular target projection surface among three projection surfaces, wherein the three projection surfaces are mutually perpendicular and the intersection point is the center point of the regular VOI, and then determine the target projection point located in the target projection area from the M projection points, and determine the target VOI based on the point cloud points corresponding to the target projection point. Since the target projection surface includes an irregular target projection area, in this way, a large number of point cloud points that interfere with the registration will not be introduced into the target VOI determined by the projection points of the M target point cloud points located in the target projection area on the irregular target projection surface, thereby improving the accuracy of the registration. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is one of the schematic diagrams of the VOI determination method provided in the embodiment of the present application;

[0012] Figure 2 This is the second schematic diagram of the VOI determination method provided in the embodiment of the present application;

[0013] Figure 3 This is the third schematic diagram of the VOI determination method provided in the embodiment of the present application;

[0014] Figure 4 This is a fourth schematic diagram of the VOI determination method provided in an embodiment of the present application;

[0015] Figure 5 This is the fifth schematic diagram of the VOI determination method provided in the embodiment of the present application;

[0016] Figure 6 This is the sixth schematic diagram of the VOI determination method provided in the embodiment of the present application;

[0017] Figure 7This is the seventh schematic diagram of the VOI determination method provided in the embodiment of the present application;

[0018] Figure 8 is a schematic diagram of multiple point cloud points in an embodiment of the present application;

[0019] Fig. 9 is a schematic diagram of an initial VOI in an embodiment of the present application;

[0020] Fig.10 is a schematic diagram of Y point cloud points in an embodiment of the present application;

[0021] Fig.11 Schematic diagram of three binary images in the embodiment of the present application;

[0022] Fig.12 is a schematic diagram of a target VOI in an embodiment of the present application;

[0023] Fig.13 is a structural diagram of a VOI determination device provided in an embodiment of the present application;

[0024] Fig.14 It is a schematic diagram of the structure of a computer device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0026] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0027] The VOI determination method provided in the embodiment of the present application is described in detail below through specific embodiments and application scenarios in conjunction with the accompanying drawings.

[0028] The VOI determination method provided in the present application can be applied to point cloud matching scenarios. For example, when a patient is given radiotherapy, in order to reduce the adverse effects of the patient's involuntary movement on the radiotherapy results, a monitoring device such as a 3D camera is usually set to monitor the patient's displacement before or during radiotherapy.

[0029] When performing radiotherapy on the patient's head, a non-invasive positioning method (such as a mask positioning method) can be used to fix the patient. However, during the positioning stage before radiotherapy or during radiotherapy, the patient's head may still move slightly inside the mask, affecting the accuracy of radiotherapy. When using a 3D camera to monitor the patient's head, the point cloud data corresponding to the regular VOI selected in the collected patient head contour data (such as Fig. 9 However, in addition to the point cloud points of the patient's face to be monitored, the regular VOI also contains a large number of point cloud points corresponding to the mask other than the monitored parts (also called external points or interference points), which will reduce the accuracy of the registration.

[0030] To this end, an embodiment of the present application provides a VOI determination method, which can be applied to a VOI determination device to extract an irregular VOI of a part to be monitored. Figure 1 As shown, the VOI determination method provided in the embodiment of the present application may include the following steps 101 to 104.

[0031] Step 101: Obtain M target point cloud points.

[0032] In the embodiment of the present application, M is a positive integer.

[0033] It can be understood that the above-mentioned M target point cloud points may include point cloud data corresponding to the target to be monitored, and the target to be monitored includes the part to be monitored. The target to be monitored may be a patient, or a phantom, etc., and the part to be monitored may be a part of the target to be monitored, such as the head, body, etc.

[0034] Here, the VOI determination device can obtain M target point cloud points from a medical imaging instrument; wherein the medical imaging instrument can include at least one of the following: a 3D camera, a passive binocular depth camera, a time-of-flight depth camera, a lidar depth camera, etc.

[0035] Step 102: Determine M projection points of the M target point cloud points on the target projection surface.

[0036] In the embodiment of the present application, the above-mentioned target projection plane is: one of three projection planes, the three projection planes are perpendicular to each other and the intersection point is the center point of the regular VOI, each target point cloud point corresponds to a projection point, and the target projection plane includes an irregular target projection area.

[0037] Here, the regular VOI may be a default VOI, a VOI determined according to M target point cloud points, or a VOI determined by a user. The regular VOI may be in a cubic shape, for example Fig. 9 The box shown is in the shape of a BOX, that is, a regular hexahedron. Of course, it can also be in other shapes, which is not specifically limited in the embodiments of the present application.

[0038] Step 103: Determine a target projection point located in the target projection area from the M projection points.

[0039] In the embodiment of the present application, after the VOI determination device determines the M projection points, a target projection point located in the target projection area is determined from the M projection points.

[0040] It should be noted that the target projection area may be a preset area on the target projection surface, or may be an area determined by a predetermined algorithm or rule.

[0041] Step 104: Determine the target VOI according to the point cloud point corresponding to the target projection point.

[0042] In the embodiment of the present application, the VOI determination device can determine the target VOI according to the point cloud points corresponding to the target projection points. The target VOI is usually an irregular VOI.

[0043] In the VOI determination method provided in the embodiment of the present application, the VOI determination device can first obtain M target point cloud points, and determine M projection points of the M target point cloud points on an irregular target projection surface among three projection surfaces, wherein the three projection surfaces are mutually perpendicular and the intersection point is the center point of the regular VOI, and then determine the target projection point located in the target projection area from the M projection points, and determine the target VOI based on the point cloud points corresponding to the target projection point. Since the target projection surface includes an irregular target projection area, in this way, a large number of point cloud points that interfere with the registration will not be introduced into the target VOI determined by the projection points of the M target point cloud points located in the target projection area on the irregular target projection surface, thereby improving the accuracy of the registration.

[0044] In the present application embodiment, combined Figure 1 ,like Figure 2 As shown, before the above step 101, the VOI determination method provided in the embodiment of the present application may further include the following steps 201 and 202.

[0045] Step 201: Acquire multiple point cloud points of the target to be monitored.

[0046] The VOI determination device may obtain a plurality of point cloud points of the target to be monitored from a medical imaging instrument. The plurality of point cloud points may be understood as: at least two point cloud points, that is, two or more point cloud points.

[0047] Here, the M target point cloud points may specifically be: some point cloud points among the multiple point cloud points.

[0048] Step 202: Determine M target point cloud points located within a regular VOI from a plurality of point cloud points of the target to be monitored.

[0049] For each of the multiple point cloud points, the VOI determination device can determine whether the distance from the point cloud point to each of the three projection planes is less than or equal to a preset value to determine whether the point cloud point is located in the regular VOI, and when it is determined that the point cloud point is located in the regular VOI, the VOI determination device can determine the point cloud point as a target point cloud point to determine M target point cloud points. Here, the preset value can be half of the length, width and height of the regular VOI.

[0050] In the embodiment of the present application, if a point cloud point is located within a regular VOI, it can be considered that the point cloud point is the point cloud point required by the user, that is, the inner point. Therefore, the VOI determination device can determine the point cloud point as a target point cloud point.

[0051] Thus, it can be seen that since the VOI determination device can first determine the M target point cloud points located within the regular VOI from the multiple point cloud points obtained, and then determine the point cloud points required by the user based on the M target point cloud points, the VOI determination device can determine the accurate target VOI based on the point cloud points required by the user, thereby improving the accuracy of point cloud registration of point cloud data.

[0052] Optionally, in the embodiment of the present application, combined with Figure 1 ,like Figure 3 As shown, before the above step 101, the VOI determination method provided in the embodiment of the present application may further include the following step 301.

[0053] Step 301: Obtain the target projection surface.

[0054] Here, the target projection plane is: a default projection plane among the three projection planes, or a projection plane determined by the VOI determination device.

[0055] Optionally, in the embodiment of the present application, combined with Figure 3 ,like Figure 4As shown, the above step 301 can be specifically implemented through the following steps 301a to 301d.

[0056] Step 301a: Obtain Y point cloud points constituting an irregular target to be monitored.

[0057] In the embodiment of the present application, the above Y point cloud points are located within a regular VOI, and Y is a positive integer.

[0058] Here, the VOI determination device may first display M target point cloud points, so that the user may input some of the M target point cloud points, so that the VOI determination device may obtain Y point cloud points based on the some of the point cloud points.

[0059] Step 301b: Obtain a projection point set of Y point cloud points on each of the three projection planes.

[0060] In the embodiment of the present application, a projection point set corresponding to a projection surface includes: Y projection points of Y point cloud points on a projection surface.

[0061] Exemplarily, after the VOI determination device determines a VOI (ie, the initial VOI in the following embodiment), the VOI determination device may determine Y point cloud points according to the user's input of some of the M target point cloud points.

[0062] For example, Fig.10 As shown, the VOI determination device can determine Y point cloud points from the M target point cloud points based on the user's input of some point cloud points in the M target point cloud points (it should be noted that the figure uses Y white dots to indicate Y point cloud points).

[0063] Here, for each of the three projection planes, the VOI determination device may first determine Y point cloud points, Y projection points on one projection plane, to obtain a projection point set corresponding to one projection plane, to determine each projection point set corresponding to each projection plane.

[0064] Exemplarily, for each of the Y point cloud points, the VOI determination device can determine the three-dimensional coordinate information of a projection point of the point cloud point on a projection surface based on the three-dimensional coordinate information of the point cloud point and the plane equation of the projection surface, so as to obtain the projection point, to obtain Y projection points on a projection surface, and to obtain a set of projection points of the Y point cloud points on a projection surface.

[0065] Step 301c: determine three projection areas according to the three projection point sets.

[0066] In the embodiment of the present application, each of the above three projection areas is: an area formed by projecting Y projection points in a projection point set onto the corresponding projection surface.

[0067] For each projection point set in the three projection point sets, the VOI determination device can use the PCA dimensionality reduction method according to the three-dimensional coordinate information of each projection point in a projection point set to obtain the two-dimensional coordinate information of each projection point, so that the VOI determination device can generate a closed projection area according to the two-dimensional coordinate information of each projection point to obtain a projection area, so as to obtain three projection areas.

[0068] Step 301d: determine the projection area with the largest area among the three projection areas as the target projection area, and determine the projection surface corresponding to the target projection area as the target projection surface.

[0069] After the VOI determination device determines the three projection areas, the VOI determination device can process each of the three projection areas using a region growing method (or a connected domain extraction method) to obtain three binary images, so that the VOI determination device can determine the projection area with the largest area among the three projection areas based on the three binary images to determine the target projection surface, so that the VOI determination device can obtain the target projection surface.

[0070] It should be noted that, for the description of the “region generation method (or connected domain extraction method)”, reference may be made to the specific description in the relevant technology, and the embodiments of the present application will not be elaborated here.

[0071] Exemplarily, for each binary image in the three binary images, one binary image includes one target area, and one target area corresponds to one projection area.

[0072] Exemplarily, the VOI determination device may first determine a binary image with the largest area of ​​the target region from the three binary images, and then determine a projection area corresponding to the binary image as the projection area with the largest area.

[0073] For example, the VOI determination device may process each of the three projection areas using a region growing method, such as Fig.11As shown, three binary images are obtained, wherein the first binary image includes a target area (e.g., area 10), the second binary image includes another target area (e.g., area 11), and the third binary image includes yet another target area (e.g., area 12). Thus, the VOI determination device can determine a binary image (i.e., the third binary image) with the largest area of ​​the target area (i.e., area 12) from the three binary images, and then determine the projection area corresponding to the third binary image as the projection area with the largest area, and determine the projection area (i.e., the projection area corresponding to the third binary image) as the target projection area, and determine the projection surface corresponding to the target projection area as the target projection surface.

[0074] Optionally, in an embodiment of the present application, the above-mentioned regular VOI is determined based on M target point cloud points, or based on user input.

[0075] Here, in the case where the regular VOI is determined based on M target point cloud points, the VOI determination device may determine the initial VOI based on the M target point cloud points using a regular VOI determination method, and determine the regular VOI based on the initial VOI.

[0076] It should be noted that, for the description of the “regular VOI determination method”, reference may be made to the specific description in the related art, and the embodiments of the present application will not be elaborated herein.

[0077] Optionally, in the embodiment of the present application, the above rule VOI is determined according to the user's input. Figure 4 ,like Figure 5 As shown, before the above step 301b, the VOI determination method provided in the embodiment of the present application may further include the following steps 401 and 402.

[0078] Step 401: Obtain X key points located outside a plurality of point cloud points of a target to be monitored.

[0079] In the embodiment of the present application, X is a positive integer greater than or equal to 4.

[0080] Here, the X key points may be vertices of the initial VOI, or may be key points determined according to user input.

[0081] Specifically, when the X key points are key points determined according to the user's input, the VOI determination device can display multiple point cloud points on the display screen, so that the user can click on some point cloud points outside the multiple point cloud points to input, so that the VOI determination device can obtain the X key points outside the multiple point cloud points of the target to be monitored according to the input parameters of the second input.

[0082] The input parameter of the second input may include at least one of the following: input position, input trajectory, etc.

[0083] Exemplarily, when the input parameter of the second input is an input position, the VOI determination device may determine a key point corresponding to the input position of each sub-input as one key point, so as to determine X key points.

[0084] Step 402: Determine three projection surfaces according to the X key points.

[0085] It can be seen that since the VOI determination device can obtain at least four key points located outside multiple point cloud points of the target to be monitored, and accurately determine three projection planes based on the at least four key points, so as to accurately determine the target VOI based on the accurate three projection planes, the accuracy of point cloud registration of point cloud data can be improved.

[0086] Optionally, in the embodiment of the present application, the above step 402 can be specifically implemented by the following steps 402a to 402c.

[0087] Step 402a: Determine the target center corresponding to the X key points.

[0088] In the embodiment of the present application, the target center is the center of the circumscribed sphere of the X key points.

[0089] Exemplarily, the target center may specifically be: the center of the smallest circumscribed sphere of the X key points.

[0090] In the embodiment of the present application, the VOI determination device may determine the three-dimensional coordinate information of the target center corresponding to the X key points based on the three-dimensional coordinate information of the X key points, so as to determine the target center.

[0091] It should be noted that for the description of the VOI determination device determining the three-dimensional coordinate information of the target center corresponding to the key point based on the three-dimensional coordinate information of the key point, reference can be made to the specific description in the relevant technology, and the embodiments of the present application will not be repeated here.

[0092] Step 402b: Determine the target coordinate information corresponding to each key point based on the coordinate information of each key point in the X key points and the coordinate information of the target center.

[0093] It can be understood that the coordinate information of each key point in the X key points is three-dimensional coordinate information, the coordinate information of the target center is three-dimensional coordinate information, and the target coordinate information corresponding to each key point is three-dimensional coordinate information.

[0094] For each of the X key points, the VOI determination device can determine the target coordinate information corresponding to a key point according to the difference between the three-dimensional coordinate information of a key point and the three-dimensional coordinate information of the target center, so as to determine the target coordinate information corresponding to each key point.

[0095] It can be understood that the target coordinate information corresponding to each key point is the decentralized three-dimensional coordinate information of each key point.

[0096] Step 402c: determine three projection surfaces according to the X target coordinate information.

[0097] Thus, it can be known that since the VOI determination device can determine the decentralized target coordinate information of each key point according to the center of the circumscribed sphere of the X key points, and accurately determine the three projection planes according to the target coordinate information corresponding to each key point, the VOI determination device can determine the accurate regular VOI based on the decentralized target coordinate information of the X key points and the accurate three projection planes, thereby improving the accuracy of point cloud registration of point cloud data.

[0098] Optionally, in the embodiment of the present application, the above step 402c can be specifically implemented through the following steps 402c1 to 402c3.

[0099] Step 402c1: construct a target matrix with X rows and three columns according to X target coordinate information.

[0100] Here, for each target coordinate information in the X target coordinate information, the VOI determination device may determine the coordinate value in one direction of the target coordinate information as an element of a row, and determine the coordinate value in another direction of the target coordinate information as another element of the row, and so on, until the coordinate value in the last direction of the target coordinate information is determined as the last element of the row, so as to obtain one row and three columns of the target matrix, so as to construct a target matrix with X rows and three columns.

[0101] Step 402c2: Determine three eigenvalues ​​and three eigenvectors after multiplying the target matrix by the transposed matrix of the target matrix.

[0102] In the embodiment of the present application, each of the three eigenvectors is a normal vector of each projection surface.

[0103] Here, the three eigenvalues ​​correspond one-to-one to the three eigenvectors.

[0104] Step 402c3: Determine three projection surfaces according to the three eigenvalues, the three eigenvectors and the plane equation in the three-dimensional space.

[0105] Here, the VOI determination device can first sort the three eigenvalues ​​according to the target order, and then substitute the eigenvector corresponding to the first eigenvalue of the sorted three eigenvalues ​​into the plane equation in the three-dimensional space to obtain the plane equation of the first projection plane, and substitute the eigenvector corresponding to the second eigenvalue into the plane equation in the three-dimensional space to obtain the plane equation of the second projection plane, and substitute the eigenvector corresponding to the third eigenvalue into the plane equation in the three-dimensional space to obtain the plane equation of the third projection plane, so as to determine the three projection planes.

[0106] The target order may be from small to large, or from large to small.

[0107] Exemplarily, assuming that the three eigenvalues ​​are eigenvalue D1, eigenvalue D2 and eigenvalue D3, D1<D2<D3, and the three eigenvectors include the eigenvector corresponding to the eigenvalue D1, such as the eigenvector {A1, B1, C1}, and the eigenvector corresponding to the eigenvalue D2, such as the eigenvector {A2, B2, C2}, and the eigenvector corresponding to the eigenvalue D3, such as the eigenvector {A3, B3, C3}. In this way, the VOI determination device can first sort the eigenvalue D1, the eigenvalue D2 and the eigenvalue D3 according to the target order (for example, from small to large order), and then substitute the eigenvector {A1, B1, C1} corresponding to the first eigenvalue (i.e., the eigenvalue D1) into the plane equation in the three-dimensional space, Ax+By+Cz+D=0, and obtain The plane equation of the first projection plane, i.e. A1x+B1y+C1z+D=0, is obtained to determine the first projection plane, and then the eigenvector {A2, B2, C2} corresponding to the second eigenvalue (i.e. eigenvalue D2) is substituted into the plane equation in the three-dimensional space, Ax+By+Cz+D=0, to obtain the plane equation of the second projection plane, i.e. A2x+B2y+C2z+D=0, to determine the second projection plane, and the eigenvector {A3, B3, C3} corresponding to the third eigenvalue (i.e. eigenvalue D3) is substituted into the plane equation in the three-dimensional space, Ax+By+Cz+D=0, to obtain the plane equation of the third projection plane, i.e. A3x+B3y+C3z+D=0, to determine the third projection plane, thereby determining the three projection planes.

[0108] Thus, it can be known that the VOI determination device can construct a target matrix according to the X target coordinate information, and determine three eigenvalues ​​and three eigenvectors according to the target matrix and the transposed matrix of the target matrix, so that the VOI determination device can accurately determine the three projection planes according to the three eigenvalues, the three eigenvectors and the plane equation in the three-dimensional space.

[0109] Optionally, in the embodiment of the present application, combined with Figure 5 ,like Figure 6As shown, after the above step 402, the VOI determination method provided in the embodiment of the present application may further include the following step 501.

[0110] Step 501: Determine a regular VOI based on X key points and three projection surfaces.

[0111] Here, after the VOI determination device determines the regular VOI, the regular VOI may be displayed so that the user can select Y point cloud points located within the regular VOI.

[0112] Optionally, in the embodiment of the present application, the above step 501 can be specifically implemented by the following steps 501a to 501c.

[0113] Step 501a: determine a first distance between each of the X key points and the first projection surface.

[0114] In the embodiment of the present application, the first projection surface is any one of the three projection surfaces.

[0115] For each of the X key points, the VOI determination device may determine a first distance between the key point and the first projection plane according to target coordinate information corresponding to the key point and a plane equation of the first projection plane, so as to determine X first distances.

[0116] Step 501b: Determine a first size parameter of the regular VOI according to the maximum distance among the X first distances.

[0117] In the embodiment of the present application, the first size parameter is: any one of the three target size parameters.

[0118] The VOI determination device may determine the first size parameter according to a maximum distance among the X first distances and a preset constant.

[0119] Exemplarily, in the embodiment of the present application, the VOI determination device may obtain a parameter according to the product of the maximum distance among the X first distances and a preset constant, and determine the parameter as the first size parameter.

[0120] Exemplarily, assuming that the maximum distance among the X first distances is a and the preset constant is 2, the VOI determination device may determine 2a as the first size parameter.

[0121] Step 501c: Determine a regular VOI based on the three target size parameters.

[0122] The VOI determination device may determine the three target size parameters as size parameters in one direction of the regular VOI with the center point of the initial VOI (ie, the preset center point) as the center, so as to obtain the regular VOI.

[0123] Exemplarily, assuming that the three target size parameters include size parameter 1, size parameter 2, and size parameter 3, the VOI determination device can take the center point of the initial VOI as the center, determine size parameter 1 as the size parameter in one direction of the regular VOI, for example, determine it as the length of the regular VOI, and determine size parameter 2 as the size parameter in another direction of the regular VOI, for example, determine it as the width of the regular VOI, and determine size parameter 3 as the size parameter in another direction of the regular VOI, for example, determine it as the height of the regular VOI, so as to obtain a regular VOI.

[0124] In the embodiment of the present application, the VOI determination device can obtain the distance between each key point of the X key points and each projection surface, and determine a size parameter of the regular VOI according to the maximum distance of the distances, so as to obtain three target size parameters, so that the VOI determination device can determine the regular VOI according to the three target size parameters.

[0125] Thus, it can be seen that since the VOI determination device can determine a size parameter according to the maximum distance between each key point and each projection surface to determine the three target size parameters, the VOI determination device can accurately determine the regular VOI according to the three target size parameters, and thus the VOI determination device can determine M projection points according to the accurate regular VOI, thereby improving the accuracy of point cloud registration of point cloud data.

[0126] It should be noted that the VOI determination method provided in the embodiment of the present application can be executed by a VOI determination device or a control module in the VOI determination device for executing the VOI determination method. In the embodiment of the present application, the VOI determination device provided in the embodiment of the present application is described by taking the VOI determination method executed by the VOI determination device as an example.

[0127] In order to more clearly explain the technical solution of the present application, a detailed example of a VOI determination method applied to a VOI determination device is given below, which can extract an irregular VOI of a part to be monitored. Figure 7 As shown, the VOI determination method provided in the embodiment of the present application may include two stages:

[0128] In the first stage, the target projection plane of the target to be monitored is determined, such as steps 601 to 606. In the second stage, after the target projection plane of the target to be monitored is determined, the target projection plane can be used to determine the template to be registered of the target to be monitored, that is, the target VOI, such as steps 607 to 611, during the actual positioning or radiotherapy process. The point cloud points corresponding to the target VOI are used as a template to compare with the point cloud points of the target to be monitored acquired in real time, thereby realizing the monitoring of the target to be monitored during the positioning or radiotherapy process.

[0129] For the first stage:

[0130] Step 601: Acquire multiple point cloud points of the target to be monitored.

[0131] Here, the VOI determination device can use a 3D camera to collect point cloud points (or contour points) of the target to be monitored to obtain multiple point cloud points of the target to be monitored, such as Figure 8 As shown, a plurality of point cloud points will be used to extract irregular VOIs for registration in the target to be monitored. Here, the target to be monitored may be a patient wearing a facial mask.

[0132] It should be noted that Figures 8 to 12 The phantoms represent actual patients.

[0133] Step 602: Acquire multiple point cloud points of the monitored part of the monitored target.

[0134] Since there are some point cloud points of non-monitored parts (such as the head) among the multiple point cloud points of the target to be monitored, the VOI determination device needs to remove the point cloud points of these non-monitored parts. To this end, the VOI determination device can first generate and display an initial VOI that covers the monitored parts of the target to be monitored and excludes the non-monitored parts, and then obtain multiple point cloud points of the monitored parts of the target to be monitored within the initial VOI.

[0135] like Fig. 9 As shown, the initial VOI in this example is a BOX-type VOI. The user can manually adjust the position of the initial VOI, such as by dragging the center point of the initial VOI. The user can also adjust the size of the initial VOI, such as by dragging the endpoints of three mutually perpendicular line segments passing through the preset center point on the initial VOI, to adjust the size of the initial VOI in different directions.

[0136] The initial VOI here can be a BOX-shaped VOI generated by the VOI determination device by default, or a regular VOI determined according to X key points input by the user, where the X key points are points outside a plurality of point cloud points of the monitored part of the monitored target, and X is a positive integer greater than or equal to 4.

[0137] It should be noted that the initial VOI is not necessarily parallel to the three coordinate axes of the coordinate system where the multiple point cloud points of the monitored target are located, and can be a regular VOI rotated around any coordinate axis, but the initial VOI is in a BOX shape.

[0138] Step 603: Acquire X key points located outside a plurality of point cloud points of the monitored part of the monitored target.

[0139] Here, the X key points are key points for determining the initial VOI. When the initial VOI is a BOX-shaped VOI generated by default, the X key points are the eight vertices of the initial VOI.

[0140] Step 604: Determine three projection surfaces according to the X key points.

[0141] Optionally, in the embodiment of the present application, the above step 604 can be implemented by the following steps 604a to 604c.

[0142] Step 604a: Determine the target center corresponding to the X key points.

[0143] In the embodiment of the present application, the target center is: the center of the circumscribed sphere of the X key points.

[0144] Here, the VOI determination device may calculate the target center according to the coordinate information (eg, three-dimensional coordinate information) of the X key points.

[0145] Step 604b: Determine the target coordinate information corresponding to each key point based on the coordinate information of each key point in the X key points and the coordinate information of the target center.

[0146] Here, the coordinate information may specifically be three-dimensional coordinate information. For each of the X key points, the VOI determination device may subtract the three-dimensional coordinate information of the target center from the coordinate information of the key point to obtain the target coordinate information corresponding to the key point, so as to obtain the target coordinate information corresponding to each key point.

[0147] Step 604c: determine three projection surfaces according to the X target coordinate information.

[0148] Optionally, in the embodiment of the present application, the above step 604c can be specifically implemented through the following steps 604c1 to 604c3.

[0149] Step 604c1: construct a target matrix with X rows and three columns according to X target coordinate information.

[0150] Here, for each target coordinate information in the X target coordinate information, the VOI determination device may determine the coordinate value in one direction of the target coordinate information as an element of a row, and determine the coordinate value in another direction of the target coordinate information as another element of the row, and so on, until the coordinate value in the last direction of the target coordinate information is determined as the last element of the row, so as to obtain one row and three columns of the target matrix, so as to construct a target matrix with X rows and three columns.

[0151] Exemplarily, assuming that the X target coordinate information is X three-dimensional coordinate information, the VOI determination device can construct a target matrix with X rows and three columns according to the X three-dimensional coordinate information.

[0152] Step 604c2: Determine three eigenvalues ​​and three eigenvectors after the target matrix is ​​multiplied by the transposed matrix of the target matrix.

[0153] In the embodiment of the present application, each of the three eigenvectors is a normal vector of each projection surface.

[0154] Here, the three eigenvalues ​​correspond one-to-one to the three eigenvectors.

[0155] Step 604c3: Determine three projection surfaces according to the three eigenvalues, the three eigenvectors and the plane equation in the three-dimensional space.

[0156] Here, the VOI determination device can first sort the three eigenvalues ​​in the target order, and then substitute the eigenvector corresponding to the first eigenvalue of the sorted three eigenvalues ​​into the plane equation in the three-dimensional space to obtain the plane equation of the first projection plane, and substitute the eigenvector corresponding to the second eigenvalue into the plane equation in the three-dimensional space to obtain the plane equation of the second projection plane, and so on, until the plane equation of the third projection plane is obtained to determine the three projection planes.

[0157] The target order may be from small to large, or from large to small.

[0158] Exemplarily, assuming that the three eigenvalues ​​are eigenvalue D1, eigenvalue D2, and eigenvalue D3, D1<D2<D3, and the three eigenvectors include the eigenvector {A1, B1, C1} corresponding to the eigenvalue D1, the eigenvector {A2, B2, C2} corresponding to the eigenvalue D2, and the eigenvector {A3, B3, C3} corresponding to the eigenvalue D3. In this way, the VOI determination device can first sort the eigenvalue D1, the eigenvalue D2, and the eigenvalue D3 according to the target order (for example, from small to large order), and then substitute the eigenvector {A1, B1, C1} corresponding to the first eigenvalue (i.e., the eigenvalue D1) into the plane equation in the three-dimensional space, Ax+By+Cz+D=0, and obtain the plane equation of the first projection surface. The program, that is, A1x+B1y+C1z+D=0, is used to determine the first projection plane, and then the eigenvector {A2, B2, C2} corresponding to the second eigenvalue (that is, eigenvalue D2) is substituted into the plane equation in the three-dimensional space, Ax+By+Cz+D=0, to obtain the plane equation of the second projection plane, that is, A2x+B2y+C2z+D=0, to determine the second projection plane, and, the eigenvector {A3, B3, C3} corresponding to the third eigenvalue (that is, eigenvalue D3) is substituted into the plane equation in the three-dimensional space, Ax+By+Cz+D=0, to obtain the plane equation of the third projection plane, that is, A3x+B3y+C3z+D=0, to determine the third projection plane, thereby determining the three projection planes.

[0159] Step 605: Determine a regular VOI based on the X key points and the three projection surfaces.

[0160] It can be understood that the VOI determination device can update the initial VOI to a regular VOI and display the regular VOI.

[0161] Optionally, in the embodiment of the present application, the above step 605 can be specifically implemented through the following steps 605a to 605c.

[0162] Step 605a: Determine a first distance between each of the X key points and the first projection surface.

[0163] In the embodiment of the present application, the first projection surface is: any one of the three projection surfaces.

[0164] Here, the VOI determination device may determine the first distance between each key point and the first projection plane respectively according to the target coordinate information corresponding to each key point and the plane equation of the first projection plane, so as to determine X first distances.

[0165] Step 605b: Determine a first size parameter of the regular VOI according to the maximum distance among the X first distances.

[0166] In the embodiment of the present application, the first size parameter is: any one of the three target size parameters.

[0167] Here, the VOI determination device may determine the first size parameter by taking twice the maximum distance among the X first distances.

[0168] Step 605c: Determine a regular VOI based on the three target size parameters.

[0169] The VOI determination device can determine the three target size parameters as size parameters in one direction of the regular VOI with the center point of the initial VOI (ie, the preset center point) as the center, so as to obtain the regular VOI, and display the regular VOI.

[0170] Step 606: Acquire the target projection surface.

[0171] Optionally, in the embodiment of the present application, the above step 606 can be specifically implemented by the following steps 606a to 606d.

[0172] Step 606a: Obtain Y point cloud points constituting the irregular target to be monitored.

[0173] In the embodiment of the present application, Y point cloud points are located within the regular VOI, and Y is a positive integer.

[0174] In one example, a user manually selects P irregular point cloud points for the monitored part of the target to be monitored (the user-defined area where the patient's part excluding the mask is located), and then interpolates to obtain Y point cloud points, where P is less than Y.

[0175] It can be understood that the area surrounded by Y point cloud points is: the part of the patient to be monitored.

[0176] For example, Fig.10 As shown, the user manually inputs P point cloud points to enclose the patient's parts of interest exposed outside the mask, including the eyes, nose, etc. The VOI determination device uses an interpolation algorithm to interpolate between the P point cloud points, insert more point cloud points, and connect the Y point cloud points into a line to form a contour line enclosing the part of interest. It should be noted that the figure uses Y white dots to indicate Y point cloud points.

[0177] Step 606b: Obtain a projection point set of Y point cloud points on each of the three projection planes.

[0178] In the embodiment of the present application, a projection point set corresponding to a projection surface includes: Y projection points of Y point cloud points on a projection surface.

[0179] Step 606c: determine three projection areas according to the three projection point sets.

[0180] In the embodiment of the present application, each of the three projection areas is: an area formed by projecting Y projection points in a projection point set onto a corresponding projection surface.

[0181] For each projection point set in the three projection point sets, the VOI determination device can use the PCA dimensionality reduction method according to the three-dimensional coordinate information of each projection point in a projection point set to obtain the two-dimensional coordinate information of each projection point, so that the VOI determination device can generate a closed projection area according to the two-dimensional coordinate information of each projection point to obtain a projection area, so as to obtain three projection areas.

[0182] It should be noted that for the description of the PCA dimensionality reduction method, reference may be made to the specific description in the relevant technology, which will not be described in detail in the embodiments of the present application.

[0183] Step 606d: determine the projection area with the largest area among the three projection areas as the target projection area, and determine the projection surface corresponding to the target projection area as the target projection surface.

[0184] After the VOI determination device determines the three projection areas, the VOI determination device can process each of the three projection areas using a region growing method (or a connected domain extraction method) to obtain three binary images, so that the VOI determination device can determine the projection area with the largest area among the three projection areas based on the three binary images to determine the target projection surface, so that the VOI determination device can obtain the target projection surface.

[0185] It should be noted that, for the description of the “region generation method (or connected domain extraction method)”, reference may be made to the specific description in the relevant technology, and the embodiments of the present application will not be elaborated here.

[0186] Exemplarily, for each binary image in the three binary images, one binary image includes one target area, and one target area corresponds to one projection area.

[0187] Exemplarily, the VOI determination device may first determine a binary image with the largest area of ​​the target region from the three binary images, and then determine a projection area corresponding to the binary image as the projection area with the largest area.

[0188] For example, the VOI determination device may process each of the three projection areas using a region growing method, such as Fig.11As shown, three binary images are obtained, wherein the first binary image includes a target area (e.g., area 10), the second binary image includes another target area (e.g., area 11), and the third binary image includes yet another target area (e.g., area 12). Thus, the VOI determination device can determine a binary image (i.e., the third binary image) with the largest area of ​​the target area (i.e., area 12) from the three binary images, and then determine the projection area corresponding to the third binary image as the projection area with the largest area, and determine the projection area (i.e., the projection area corresponding to the third binary image) as the target projection area, and determine the projection surface corresponding to the target projection area as the target projection surface.

[0189] For the second phase:

[0190] Step 607: Acquire multiple point cloud points of the target to be monitored.

[0191] Here, the VOI determination device may again utilize the 3D camera to collect point cloud points (or contour points) of the target to be monitored, so as to obtain a plurality of point cloud points of the target to be monitored again.

[0192] Step 608: Determine M target point cloud points located within the regular VOI from the multiple point cloud points of the target to be monitored.

[0193] Here, for each point cloud point among the multiple point cloud points, the VOI determination device can determine whether the distance from a point cloud point to each of the three projection planes is less than or equal to a preset value to determine whether the point cloud point is located within the regular VOI, and when it is determined that the point cloud point is located within the regular VOI, the VOI determination device can determine the point cloud point as a target point cloud point to determine M target point cloud points.

[0194] Here, the preset value is half of the length, width and height of the regular VOI.

[0195] Step 609: Determine M projection points of the M target point cloud points on the target projection surface.

[0196] In the embodiment of the present application, the target projection plane is: one of three projection planes, the three projection planes are perpendicular to each other and the intersection point is the center point of the regular VOI; the target projection plane includes an irregular target projection area.

[0197] Step 610: Determine a target projection point located in a target projection area from the M projection points.

[0198] Here, the VOI determination device may determine a target projection point located in the target projection area from the M projection points based on the two-dimensional coordinate information of the M projection points.

[0199] Specifically, the VOI determination device may determine the target projection point from the M projection points according to the two-dimensional coordinate information of the M projection points and a binary image with the largest area of ​​the target area.

[0200] Exemplarily, in an embodiment of the present application, when the target projection point includes multiple projection points, for each of the M projection points, the VOI determination device can first determine the corresponding pixel point from a binary image with the largest area based on the two-dimensional coordinate information of the projection point, and then, when the grayscale value of the pixel point is 1, determine the projection point as one of the multiple projection points to determine the multiple projection points (i.e., the target projection point).

[0201] Step 611: Determine the target VOI according to the point cloud point corresponding to the target projection point.

[0202] Here, the VOI determination device may generate a target VOI according to the point cloud points corresponding to the target projection points, so as to determine the target VOI.

[0203] For example, Fig.12 As shown, the VOI determination device can determine the target VOI according to the point cloud points corresponding to the target projection points (it should be noted that the figure is illustrated by the shaded area).

[0204] The VOI determination method provided in the embodiment of the present application, since the target projection surface includes an irregular target projection area, in the target VOI determined by the projection points of M target point cloud points located within the target projection area on the irregular target projection surface, a large number of point cloud points interfering with the registration will not be introduced, thereby improving the accuracy of the registration.

[0205] Fig.13 FIG. 2 shows a possible structural diagram of a VOI determination device involved in an embodiment of the present application. Fig.13 As shown, the VOI determination device 60 may include: an acquisition module 61 , a first determination module 62 , a second determination module 63 and a third determination module 64 .

[0206] The acquisition module 61 is used to acquire M target point cloud points, where M is a positive integer.

[0207] The first determination module 62 is used to determine the M projection points of the M target point cloud points acquired by the acquisition module 61 on the target projection plane, where the target projection plane is: one of the three projection planes, the three projection planes are perpendicular to each other and the intersection point is the center point of the regular VOI; the target projection plane includes an irregular target projection area. The second determination module 63 is used to determine the target projection point located in the target projection area from the M projection points determined by the first determination module 62. The third determination module 64 is used to determine the target VOI according to the point cloud point corresponding to the target projection point determined by the second determination module 63.

[0208] In a possible implementation, the acquisition module 61 is also used to acquire multiple point cloud points of the target to be monitored. The VOI determination device 60 provided in the embodiment of the present application may also include: a fourth determination module. The fourth determination module is used to determine M target point cloud points located within the regular VOI from the multiple point cloud points of the target to be monitored acquired by the acquisition module 61.

[0209] In a possible implementation, the acquisition module 61 is further used to acquire a target projection surface.

[0210] In a possible implementation, the acquisition module 61 is specifically used to acquire Y point cloud points constituting an irregular target to be monitored, the Y point cloud points are located within a regular VOI, and Y is a positive integer; and to acquire a projection point set of the Y point cloud points on each of the three projection planes, and a projection point set corresponding to one projection plane includes: Y projection points of the Y point cloud points on one projection plane. The VOI determination device 60 provided in the embodiment of the present application may also include: a fifth determination module. Among them, the fifth determination module is used to determine three projection areas based on the three projection point sets, each projection area is: an area formed by projecting Y projection points in a projection point set onto a corresponding projection plane; and the projection area with the largest area among the three projection areas is determined as the target projection area, and the projection plane corresponding to the target projection area is determined as the target projection plane.

[0211] In a possible implementation, the acquisition module 61 is further used to acquire X key points located outside the plurality of point cloud points of the target to be monitored, where X is a positive integer greater than or equal to 4. The VOI determination device 60 provided in the embodiment of the present application may further include: a sixth determination module. The sixth determination module is used to determine three projection surfaces according to the X key points acquired by the acquisition module 61.

[0212] In a possible implementation, the sixth determination module is specifically configured to determine a target center corresponding to the X key points, where the target center is the center of a circumscribed sphere of the X key points; and determine target coordinate information corresponding to each key point according to coordinate information of each key point in the X key points and coordinate information of the target center; and determine three projection surfaces according to the X target coordinate information.

[0213] In a possible implementation, the sixth determination module is specifically used to construct a target matrix with X rows and three columns based on X target coordinate information; and determine three eigenvalues ​​and three eigenvectors after the transposed matrix of the target matrix is ​​multiplied by the target matrix, each eigenvector being a normal vector of each projection surface; and, determine three projection surfaces based on the three eigenvalues, the three eigenvectors and the plane equation in the three-dimensional space.

[0214] In a possible implementation, the VOI determination device 60 provided in the embodiment of the present application may further include: a seventh determination module. The seventh determination module is configured to determine a regular VOI according to X key points and three projection planes.

[0215] In a possible implementation, the seventh determination module is specifically configured to respectively determine a first distance between each of the X key points and a first projection plane, where the first projection plane is any one of the three projection planes; and determine a first size parameter of the regular VOI according to a maximum distance among the X first distances, where the first size parameter is any one of the three target size parameters; and determine the regular VOI based on the three target size parameters.

[0216] The VOI determination device provided in the embodiment of the present application can first obtain M target point cloud points, and determine M projection points of the M target point cloud points on an irregular target projection surface among three projection surfaces, wherein the three projection surfaces are perpendicular to each other and the intersection point is the center point of the regular VOI, and then determine the target projection point located in the target projection area from the M projection points, and determine the target VOI based on the point cloud points corresponding to the target projection point. Since the target projection surface includes an irregular target projection area, in this way, a large number of point cloud points that interfere with the registration will not be introduced into the target VOI determined by the projection points of the M target point cloud points located in the target projection area on the irregular target projection surface, thereby improving the accuracy of the registration.

[0217] It should be noted that the above modules can be functional modules or program modules, and can be implemented by software or hardware. For modules implemented by hardware, the above modules can be located in the same processor; or the above modules can be located in different processors in any combination.

[0218] In addition, combined Figures 1 to 7 The VOI determination method described in the embodiment of the present application may be implemented by a computer device, that is, the VOI determination apparatus may be a computer device. Fig.14 FIG. 1 is a schematic diagram of the hardware structure of a computer device in an embodiment.

[0219] The computer device may include a processor 71 , a memory 72 storing computer program instructions, and programs or instructions stored on the memory 72 and executable on the processor 71 .

[0220] Specifically, the processor 71 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0221] Among them, the memory 72 may include a large capacity memory for data or instructions. For example, but not limitation, the memory 72 may include a hard disk drive (HDD), a floppy disk drive, a solid-state drive (SSD), a flash memory, an optical disk, a magneto-optical disk, a tape or a universal serial bus (USB) drive or a combination of two or more of these. In appropriate cases, the memory 72 may include a removable or non-removable (or fixed) medium. In appropriate cases, the memory 72 may be inside or outside the data processing device. In a specific embodiment, the memory 72 is a non-volatile memory. In a specific embodiment, the memory 72 includes a read-only memory (ROM) and a random access memory (RAM). In appropriate cases, the ROM may be a mask-programmed ROM, a programmable ROM (PROM), an erasable PROM (EPROM), an electrically erasable PROM (EEPROM), an electrically alterable ROM (EAROM), or a flash memory (FLASH), or a combination of two or more of these. In appropriate cases, the RAM may be a static random access memory (SRAM) or a dynamic random access memory (DRAM), wherein the DRAM may be a fast page mode dynamic random access memory (FPMDRAM), an extended data out dynamic random access memory (EDODRAM), a synchronous dynamic random access memory (SDRAM), or the like.

[0222] The memory 72 may be used to store or cache various data files required for processing and / or communication, as well as possible computer program instructions executed by the processor 71 .

[0223] The processor 71 implements any one of the VOI determination methods in the above embodiments by reading and executing computer program instructions stored in the memory 72 .

[0224] In some embodiments, the computer device may further include a communication interface 73 and a bus 70. Fig.14 As shown, the processor 71, the memory 72, and the communication interface 73 are connected via a bus 70 and communicate with each other.

[0225] The communication interface 73 is used to implement communication between the modules, devices, units and / or equipment in the embodiment of the present application. The communication interface 73 can also implement data communication with other components such as: external devices, image / data acquisition equipment, databases, external storage, and image / data processing workstations.

[0226] The bus 70 includes hardware, software or both, and couples the components of the computer device to each other. The bus 70 includes but is not limited to at least one of the following: a data bus, an address bus, a control bus, an expansion bus, and a local bus. By way of example and not limitation, bus 70 may include accelerated graphics port (AGP) or other graphics bus, extended industry standard architecture (EISA) bus, front side bus (FSB), hyper transport (HT) interconnect, industry standard architecture (ISA) bus, infiniband interconnect, low pin count (LPC) bus, memory bus, micro channel architecture (MCA) bus, peripheral component interconnect (PCI) bus, PCI-express (PCI-X) bus, serial advanced technology attachment (SATA) bus, video electronics standards association local bus (VLB) bus or other suitable bus or combination of two or more of these. Where appropriate, bus 70 may include one or more buses. Although the embodiments of the present application describe and illustrate specific buses, the present application contemplates any suitable bus or interconnect.

[0227] The computer device can execute the VOI determination method in the embodiment of the present application based on the acquired computer instructions, thereby realizing the combination Figures 1 to 7 Described VOI determination method.

[0228] An embodiment of the present application also provides a readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by a processor, each process of the above-mentioned VOI determination method embodiment is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0229] The processor is a processor in the computer device described in the above embodiment. The readable storage medium includes a computer-readable storage medium, such as a computer read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc. Here, the computer-readable storage medium can be a non-volatile storage medium or a volatile storage medium.

[0230] An embodiment of the present application further provides a chip, which includes a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is used to run programs or instructions to implement the various processes of the above-mentioned VOI determination method embodiment, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0231] It should be understood that the chip mentioned in the embodiments of the present application can also be called a system-level chip, a system chip, a chip system or a system-on-chip chip, etc.

[0232] It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0233] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a computer software product, which is stored in a storage medium (such as ROM / RAM, a disk, or an optical disk), and includes a number of instructions for enabling a terminal (which can be a computer, etc.) to execute the methods described in each embodiment of the present application.

[0234] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A method for determining a volume of interest (VOI), characterized in that: The method comprises: Get M target point cloud points, where M is a positive integer; Determine M projection points of the M target point cloud points on a target projection plane, wherein the target projection plane is: one of three projection planes, wherein the three projection planes are perpendicular to each other and the intersection point is the center point of a regular VOI; and the target projection plane includes an irregular target projection area; Determine a target projection point located in the target projection area from the M projection points; Determine the target VOI according to the point cloud point corresponding to the target projection point; Before obtaining the M target point cloud points, the method further includes: Acquire the target projection surface; The obtaining of the target projection surface comprises: Acquire Y point cloud points constituting an irregular target to be monitored, wherein the Y point cloud points are located within the regular VOI, and Y is a positive integer; Obtaining a projection point set of the Y point cloud points on each of the three projection planes, wherein the projection point set corresponding to one projection plane includes: Y projection points of the Y point cloud points on one projection plane; According to the three projection point sets, three projection areas are determined, each of which is: an area formed by projecting Y projection points in a projection point set onto a corresponding projection surface; Determine the projection area with the largest area among the three projection areas as the target projection area, and determine the projection surface corresponding to the target projection area as the target projection surface; Before obtaining the projection point set of the Y point cloud points on each of the three projection surfaces, the method further includes: Obtaining X key points located outside the plurality of point cloud points of the target to be monitored, where X is a positive integer greater than or equal to 4; Determine the three projection surfaces according to the X key points; Determining the three projection surfaces according to the X key points includes: Determine the target center corresponding to the X key points, where the target center is: the center of the circumscribed sphere of the X key points; Determine the target coordinate information corresponding to each key point according to the coordinate information of each key point in the X key points and the coordinate information of the target center; The three projection surfaces are determined according to the X target coordinate information.

2. The method according to claim 1, characterized in that: Before determining the M projection points of the M target point cloud points on the target projection surface, the method further includes: Obtain multiple point cloud points of the target to be monitored; From the multiple point cloud points of the target to be monitored, M target point cloud points located within the regular VOI are determined.

3. The method according to claim 1, characterized in that The step of determining the three projection surfaces according to the X target coordinate information includes: According to the X target coordinate information, construct a target matrix with X rows and three columns; Determine three eigenvalues ​​and three eigenvectors after multiplying the target matrix by the transposed matrix of the target matrix, each eigenvector being a normal vector of each projection surface; The three projection surfaces are determined according to the three eigenvalues, the three eigenvectors and a plane equation in three-dimensional space.

4. The method according to claim 1, characterized in that: After determining the three projection surfaces according to the X key points, the method further includes: The regular VOI is determined according to the X key points and the three projection planes.

5. The method according to claim 4, characterized in that The determining the regular VOI according to the X key points and the three projection planes includes: Determine respectively a first distance between each of the X key points and a first projection plane, where the first projection plane is: any one of the three projection planes; Determine a first size parameter of the regular VOI according to a maximum distance among the X first distances, where the first size parameter is: any one of the three target size parameters; Based on the three target size parameters, the regular VOI is determined.

6. A VOI determination device, characterized in that: The method comprises a processor, a memory, and a program or instruction stored in the memory and executable on the processor, wherein the program or instruction, when executed by the processor, implements the steps of the VOI determination method according to any one of claims 1 to 5.

Images