A security imaging method, device, computer equipment and storage medium

Abstract

Embodiments of the present application provide a security imaging method and device, computer equipment and a storage medium. The method comprises obtaining first initial point cloud data obtained by scanning a target object by a first antenna array, and second initial point cloud data obtained by scanning the target object by a second antenna array. Then, the first initial point cloud data and the second initial point cloud data are corrected by using a correction parameter determined in the absence of the target object, to obtain first target point cloud data and second target point cloud data. Then, the first target point cloud data and the second target point cloud data are spliced to obtain a three-dimensional image of the target object. Since the correction parameter reflects the measurement error between the first antenna array and the second antenna array, the error of the two antenna arrays can be eliminated by using the correction parameter, and the splicing of the point cloud data is realized, and an accurate three-dimensional image of the target object is obtained.

Description

Technical Field

[0001] This application relates to the field of security inspection technology, and in particular to a security inspection imaging method, device, computer equipment, and storage medium. Background Technology

[0002] As public safety issues have gradually become a focus of social attention, higher demands have been placed on the accuracy, real-time performance, intelligence, and environmental adaptability of security inspection systems. In recent years, with the continuous expansion of the research team on millimeter-wave security imaging technology, a large number of scientific research achievements have emerged.

[0003] Currently, millimeter-wave security imaging technology can be applied to security scanners for human body inspection. Traditional planar millimeter-wave / terahertz human body scanners image the human body separately using two arrays, front and back, to generate two images as human body detection images, which are then used by security personnel for security checks.

[0004] However, traditional planar millimeter-wave / terahertz body scanners suffer from low accuracy in generating human body detection images. Summary of the Invention

[0005] This application provides a security inspection imaging method, apparatus, computer equipment, and storage medium, which can improve the accuracy of the detection images obtained by detecting target objects.

[0006] The first aspect of this application provides a security inspection imaging method, including:

[0007] Acquire first initial point cloud data and second initial point cloud data, wherein the first initial point cloud data is obtained by scanning the front of the target object with the first antenna array and the second initial point cloud data is obtained by scanning the back of the target object with the second antenna array.

[0008] The first initial point cloud data and the second initial point cloud data are corrected using correction parameters to obtain the first target point cloud data and the second target point cloud data. The correction parameters are determined based on the first reflection data and the second reflection data. The first reflection data is obtained by scanning the first reflection reference object with the first antenna array surface, and the second reflection data is obtained by scanning the second reflection reference object with the second antenna array surface. The first reflection reference object is located in the non-antenna area of ​​the second antenna array surface, and the second reflection reference object is located in the non-antenna area of ​​the first antenna array surface.

[0009] The point cloud data of the first target and the point cloud data of the second target are stitched together to obtain a three-dimensional image of the target object.

[0010] In one feasible implementation, the method for determining the correction parameters includes:

[0011] Acquire the first reflection data and the second reflection data;

[0012] The correction parameters are determined based on the first reflection data, the second reflection data, the nominal coordinates of the first reflection reference object, the nominal coordinates of the second reflection reference object, and the nominal coordinates of the center of the second linear array.

[0013] In one feasible implementation, the correction parameters include a first error amount and a second error amount;

[0014] Based on the first reflection data, the second reflection data, the nominal coordinates of the first reflection reference object, the nominal coordinates of the second reflection reference object, and the nominal coordinates of the center of the second linear array, the correction parameters are determined, including:

[0015] Based on the first reflection data and the nominal coordinates of the first reflection reference object, determine the first error between the first antenna array and the second antenna array;

[0016] Based on the second reflection data, the nominal coordinates of the second reflection reference object, and the nominal coordinates of the center of the second antenna array, the second error between the first antenna array and the second antenna array is determined, and the first error plus the second error is used as the correction parameter.

[0017] In one feasible implementation, acquiring the first reflection data and the second reflection data includes:

[0018] Acquire first initial reflection data and second initial reflection data; the first initial reflection data is obtained by scanning the first antenna array surface with the first reflection reference object, and the second initial reflection data is obtained by scanning the second antenna array surface with the second reflection reference object;

[0019] The first reflection data and the second reflection data are determined based on the first initial reflection data, the second initial reflection data, and the first preset reflection intensity threshold.

[0020] In one feasible implementation, determining the first reflection data and the second reflection data based on the first initial reflection data, the second initial reflection data, and the first preset reflection intensity threshold includes:

[0021] Obtain a first reflection data unit from the first initial reflection data, wherein the reflection intensity of the first reflection data unit is greater than a first preset reflection intensity threshold;

[0022] The point cloud data composed of each first reflection data unit is used as the first reflection data;

[0023] Obtain the second reflection data unit from the second initial reflection data, wherein the reflection intensity of the second reflection data unit is greater than the first preset reflection intensity threshold;

[0024] The point cloud data composed of each second reflection data unit is used as the second reflection data.

[0025] In one feasible implementation, correction parameters are used to correct the first initial point cloud data and the second initial point cloud data to obtain the first target point cloud data and the second target point cloud data, including:

[0026] The first target point cloud data is determined based on the first initial point cloud data and the first error amount of the correction parameters;

[0027] Based on the second initial point cloud data and the second error amount of the correction parameters, the reference point cloud data is determined, and the reference point cloud data is subjected to coordinate transformation to obtain the second target point cloud data.

[0028] In one feasible implementation, the reference point cloud data is transformed to obtain the second target point cloud data, including:

[0029] Based on a preset coordinate transformation relationship, the reference point cloud data is transformed to obtain the second target point cloud data. The preset coordinate transformation relationship is the mapping relationship between the first antenna array and the second antenna array.

[0030] In one feasible implementation, the first target point cloud data and the second target point cloud data are stereo stitched together to obtain a three-dimensional stereo image of the target object, including:

[0031] The first target point cloud data is normalized to obtain the first normalized point cloud data, and the second target point cloud data is normalized to obtain the second normalized point cloud data.

[0032] The first normalized point cloud data and the second normalized point cloud data are stitched together in a stereoscopic manner to obtain a three-dimensional stereoscopic image of the target object.

[0033] In one feasible implementation, the first target point cloud data is normalized to obtain first normalized point cloud data, and the second target point cloud data is normalized to obtain second normalized point cloud data, including:

[0034] Obtain the maximum value of the first reflection intensity of the first target point cloud data and the maximum value of the second reflection intensity of the second target point cloud data;

[0035] The first normalized point cloud data is determined based on the reflection intensity of each data unit in the first target point cloud data and the maximum value of the first reflection intensity.

[0036] The second normalized point cloud data is determined based on the reflection intensity of each data unit and the maximum value of the second reflection intensity in the second target point cloud data.

[0037] In one feasible implementation, the first normalized point cloud data and the second normalized point cloud data are stereo stitched together to obtain a three-dimensional stereo image of the target object, including:

[0038] A 3D stitching method is used to stitch together the normalized data units in the first and second normalized point cloud data into the same coordinate system.

[0039] The reflection intensity values ​​corresponding to the normalized data units with the same coordinates are processed to obtain a three-dimensional image of the target object.

[0040] In one feasible implementation, acquiring the first initial point cloud data and the second initial point cloud data includes:

[0041] Acquire point cloud data of a first target object and point cloud data of a second target object; wherein, the point cloud data of the first target object is obtained by scanning the target object with the first antenna array, and the point cloud data of the second target object is obtained by scanning the target object with the second antenna array;

[0042] Based on the point cloud data of the first target object, the point cloud data of the second target object, and the second preset reflection intensity threshold, the first initial point cloud data and the second initial point cloud data are determined.

[0043] In one feasible implementation, determining the first initial point cloud data and the second initial point cloud data based on the first target object point cloud data, the second target object point cloud data, and the second preset reflection intensity threshold includes:

[0044] Obtain the third reflection intensity unit in the point cloud data of the first target object; wherein the reflection intensity of the third reflection data unit is greater than the second preset reflection intensity threshold.

[0045] The point cloud data composed of each third reflection intensity unit is used as the first initial point cloud data;

[0046] Obtain the fourth reflection data unit in the point cloud data of the second target object; wherein the reflection intensity of the fourth reflection data unit is greater than the second preset reflection intensity threshold.

[0047] The point cloud data composed of each fourth reflection data unit is used as the second initial point cloud data.

[0048] A second aspect of this application provides a security inspection imaging device, comprising:

[0049] The point cloud acquisition module is used to acquire first initial point cloud data and second initial point cloud data. The first initial point cloud data is obtained by scanning the front of the target object with the first antenna array, and the second initial point cloud data is obtained by scanning the back of the target object with the second antenna array.

[0050] The correction parameter determination module is used to determine correction parameters based on the first reflection data and the second reflection data. The first reflection data is obtained by scanning the first antenna array surface with the first reflection reference object, and the second reflection data is obtained by scanning the second antenna array surface with the second reflection reference object. The first reflection reference object is located in the non-antenna area on the second antenna array surface, and the second reflection reference object is located in the non-antenna area on the first antenna array surface.

[0051] The correction module is used to correct the first initial point cloud data and the second initial point cloud data using correction parameters to obtain the first target point cloud data and the second target point cloud data.

[0052] The stitching module is used to stitch together the point cloud data of the first target and the point cloud data of the second target to obtain a three-dimensional image of the target object.

[0053] A third aspect of this application provides a computer device, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the method described in the first aspect above.

[0054] A fourth aspect of this application provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the method described in the first aspect above.

[0055] The technical solution provided in this application can achieve at least the following beneficial effects:

[0056] The security inspection imaging method, apparatus, computer equipment, and storage medium provided in this application acquire first initial point cloud data obtained by scanning a target object with a first antenna array, and second initial point cloud data obtained by scanning a target object with a second linear array. Then, using correction parameters determined in the absence of a target object, the first and second initial point cloud data are corrected to obtain first and second target point cloud data. Finally, the first and second target point cloud data are stitched together to obtain a three-dimensional image of the target object. Since the correction parameters are jointly determined based on the first reflection data obtained by scanning a first reflective reference object with a first antenna array, and the second reflection data obtained by scanning a second reflective reference object with a second linear array, they can reflect the measurement error between the first and second antenna arrays. By using these correction parameters to correct the data obtained after scanning the target object with the two antenna arrays, the first and second target point cloud data can be stitched together to obtain an accurate three-dimensional image of the target object, effectively enhancing the representation of the target object's side profile, thus allowing staff to intuitively observe the side profile of the target object. Attached Figure Description

[0057] Figure 1 This is a schematic diagram illustrating the application environment of a security inspection device according to an exemplary embodiment of this application;

[0058] Figure 2 This is a schematic flowchart illustrating a security inspection imaging method according to an exemplary embodiment of this application;

[0059] Figure 3 This is an exemplary embodiment of the present application illustrating an image composed of a first initial point cloud data;

[0060] Figure 4 This is an exemplary embodiment of the present application illustrating an image composed of a second initial point cloud data;

[0061] Figure 5 This is a schematic diagram of a calibration parameter scanning environment structure shown in an exemplary embodiment of this application;

[0062] Figure 6 This is a flowchart illustrating a method for determining correction parameters according to an exemplary embodiment of this application;

[0063] Figure 7 This is a three-dimensional image of the target object shown in an exemplary embodiment of this application;

[0064] Figure 8This is a schematic diagram of a security inspection imaging device shown in an exemplary embodiment of this application;

[0065] Figure 9 This is a schematic diagram of another security inspection imaging device illustrated in an exemplary embodiment of this application;

[0066] Figure 10 This is a schematic diagram of a computer device structure shown in an exemplary embodiment of this application. Detailed Implementation

[0067] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0068] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0069] The embodiments disclosed herein can be applied to electronic devices such as terminal devices, computer systems, and servers, and can operate together with a wide range of other general-purpose or special-purpose computing system environments or configurations. Examples of well-known terminal devices, computing systems, environments, and / or configurations suitable for use with electronic devices such as terminal devices, computer systems, and servers include, but are not limited to: personal computer systems, server computer systems, thin clients, thick clients, handheld or laptop devices, microprocessor-based systems, set-top boxes, programmable consumer electronics, network PCs, minicomputer systems, mainframe computer systems, and distributed cloud computing environments that include any of the above systems.

[0070] Electronic devices such as terminal devices, computer systems, and servers can be described in the general context of computer system executable instructions (such as program modules) executed by a computer system. Typically, program modules can include routines, programs, object programs, components, logic, data structures, etc., which perform specific tasks or implement specific abstract data types. Computer systems / servers can be implemented in distributed cloud computing environments, where tasks are executed by remote processing devices linked through communication networks. In distributed cloud computing environments, program modules can reside on local or remote computing system storage media, including storage devices.

[0071] In recent years, public safety issues have attracted widespread attention from the international community, and security checks in public places have gradually become a focus of social concern, placing higher demands on the accuracy, real-time performance, intelligence, and environmental adaptability of security check systems.

[0072] Traditional security screening equipment, such as metal detectors and X-ray imaging devices, has several limitations. Metal detectors can detect prohibited metal items carried by individuals, but they cannot detect non-metallic prohibited items such as ceramic knives or plastic explosives, and they cannot pinpoint the exact location of prohibited items. X-ray imaging devices can provide high-resolution images of individuals carrying concealed items, but because X-rays are ionizing, they are not suitable for human body security screening. Therefore, millimeter-wave security imaging, due to its high security, good penetration, and the different electromagnetic scattering characteristics of various materials, is gradually becoming the mainstream security screening equipment.

[0073] Traditional planar millimeter-wave / terahertz security scanners scan the target object using two antenna arrays, one facing forward and one facing backward, generating two images to allow staff to screen specific items. However, traditional planar millimeter-wave / terahertz security scanners cannot display images of the target object's side profile. Furthermore, because the data obtained from the two antenna arrays scanning the target object are not in the same spatial coordinate system, they cannot be simply stitched together.

[0074] The security inspection imaging method provided in this application embodiment can be applied to, for example... Figure 1The application environment shown includes a security inspection device 10, which comprises a first antenna array 102, a second antenna array 104, a data acquisition device 106, and a terminal device 108 for data processing. A first reflective reference 1021 is provided in the non-antenna area of ​​the first antenna array 102, and a second reflective reference 1041 is provided in the non-antenna area of ​​the second antenna array 104. The data acquisition device 106 can communicate with the terminal device 108 via a network. The data acquisition device 106 can acquire echo data obtained by scanning the front of the target object with the first antenna array 102 and the back of the target object with the second antenna array 104, and send the echo data to the data processing terminal device 108 for data processing to obtain first and second initial point cloud data. Prior to this, in the absence of a target object, the data acquisition device 106 can acquire the echo data obtained by the first antenna array 102 scanning the second reflective reference object, and the echo data obtained by the second antenna array 104 scanning the first reflective reference object 1021, and send them to the terminal device 108. This allows the terminal device 108 to determine the correction parameters measured between the first antenna array 102 and the second antenna array 104. The correction parameters can then be used to correct the initial point cloud data and the second initial point cloud data to obtain the first target point cloud data and the second target point cloud data. These two data can then be stereoscopically stitched together to obtain a three-dimensional stereoscopic image of the target object. The terminal device 108 can be configured as either a host computer or a slave computer within the security inspection device 10; no limitation is imposed here.

[0075] The security inspection imaging method, apparatus, computer equipment, and storage medium in this application embodiment may include, but are not limited to, mobile phones, tablets, laptops, ultra-mobile personal computers (UMPCs), handheld computers, touch-screen TVs, walkie-talkies, netbooks, point-of-sale (POS) machines, personal digital assistants (PDAs), wearable devices, virtual reality devices, wireless USB flash drives, Bluetooth speakers / headphones / glasses, in-vehicle pre-installed devices, dashcams, security equipment, and other fixed or mobile terminal devices. The following description, in conjunction with the accompanying drawings, exemplarily illustrates the security inspection imaging method of this application embodiment, which uses a terminal device as the execution subject.

[0076] Figure 2 This is a schematic flowchart illustrating a security inspection imaging method according to an exemplary embodiment of this application. (Refer to...) Figure 2 As shown, security inspection imaging methods include:

[0077] S202, acquire first initial point cloud data and second initial point cloud data, wherein the first initial point cloud data is obtained by scanning the front of the target object with the first antenna array and the second initial point cloud data is obtained by scanning the back of the target object with the second antenna array.

[0078] It should be noted that the target object can be a human body, animal, etc., without restriction. The first and second antenna arrays are arranged facing each other. (See reference...) Figure 1 As shown, the first antenna array and the second antenna array are arranged opposite to each other, and the first antenna array 102 and the second antenna array 104 can be respectively set on both sides of the target object (e.g., a human body). The size of the first antenna array and the second antenna array is the same. Both the first initial point cloud data and the second initial point cloud data are three-dimensional data. The three dimensions of the three-dimensional data represent the width, depth, and height information with the center of the first antenna array or the center of the second antenna array as the origin, respectively. The numerical value of the three-dimensional data represents the reflection intensity of different data units in the spatial region between the first antenna array and the second antenna array. The first initial point cloud data is the point cloud data of the target object measured with the center of the first antenna array as the origin. The second initial point cloud data is the point cloud data of the target object measured with the center of the second antenna array as the origin. Each data unit is a plurality of data units of the same size, pre-divided into the spatial region between the first antenna array and the second antenna array.

[0079] Specifically, when scanning a target object is required, once the target object is located within a preset scanning area between the first and second antenna arrays, the first and second antenna arrays simultaneously transmit signal waves of the same frequency to the target object. The data acquisition device collects in real time the first echo signal reflected from the target object to the first antenna array and the second echo signal reflected to the second antenna array after receiving the signal wave. The first and second echo signals are then transmitted to a terminal device for data processing to generate first and second initial point cloud data corresponding to the target object. Both the first and second initial point cloud data include the coordinates and reflection intensity of multiple data units. Figure 3 This is a schematic diagram of the image formed by the first initial point cloud data. Figure 4 This is a schematic diagram of the image formed by the second initial point cloud data.

[0080] In some feasible implementations, step 202 can be performed as follows:

[0081] S2022, acquire point cloud data of the first target object and point cloud data of the second target object. The first target object point cloud data is obtained by scanning the target object with the first antenna array, and the second target object point cloud data is obtained by scanning the target object with the second antenna array.

[0082] It should be noted that when the first antenna array scans the target object, the signal wave emitted towards the target object will not only be reflected back by the target object, but also reflected by the second antenna array when it reaches a point outside the target object. Similarly, when the second antenna array scans the target object, the signal wave emitted towards the target object will not only be reflected back by the target object, but also reflected by the first antenna array when it reaches a point outside the target object.

[0083] In other words, the first echo signal includes the first object echo signal reflected by the target object and the second array echo signal reflected by the second antenna array. Furthermore, since the distance the signal wave travels to the target object is less than the distance the signal source travels to the second antenna array, the signal strength of the first object echo signal reflected by the target object is stronger, while the signal strength of the second array echo signal is weaker.

[0084] The second echo signal includes the second object echo signal reflected by the target object and the first array echo signal reflected by the first antenna array. Because the distance the signal wave travels to the target object is less than the distance the signal source travels to the first antenna array, the signal strength of the second object echo signal reflected by the target object is stronger, while the signal strength of the first array echo signal is weaker.

[0085] Specifically, after the terminal device receives the first echo signal and the second echo signal sent by the data acquisition device, it generates first target object point cloud data from the first echo signal and second target object point cloud data from the second echo signal using a point cloud data generation method, thus acquiring both first and second target object point cloud data. The first target object point cloud data is the point cloud data of the target object measured with the center of the first antenna array as the origin. The second target object point cloud data is the point cloud data of the target object measured with the center of the second antenna array as the origin. The first target object point cloud data includes the first initial point cloud data of the target object and the point cloud data reflected by the second antenna array. The second target object point cloud data includes the second initial point cloud data of the target object and the point cloud data reflected by the first antenna array.

[0086] S2024, Based on the first target object point cloud data, the second target object point cloud data, and the second preset reflection intensity threshold, determine the first initial point cloud data and the second initial point cloud data.

[0087] Specifically, since each data unit in both the first and second target object point cloud data has a corresponding reflection intensity value, a second preset reflection intensity threshold can be used to filter the data units corresponding to the target object in the first target object point cloud data, thereby determining the first initial point cloud data consisting only of the data units corresponding to the target object. Similarly, the second preset reflection intensity threshold can be used to filter the data units corresponding to the target object in the second target object point cloud data, thereby determining the second initial point cloud data consisting only of the data units corresponding to the target object. The preset second reflection intensity threshold is an empirical value determined by the developers based on multiple experiments and can be adjusted according to actual conditions; it is not restricted here.

[0088] In this embodiment, first target object point cloud data and second target object point cloud data can be acquired first. Then, based on the first target object point cloud data, the second target object point cloud data, and a second preset reflection intensity threshold, first initial point cloud data and second initial point cloud data are determined. Since the first target object point cloud data is obtained by scanning the target object with the first antenna array, and the second target object point cloud data is obtained by scanning the target object with the second antenna array, they may include reflected echoes other than those from the target object. Therefore, the second preset reflection intensity threshold can be used to filter the first and second target object point cloud data, obtaining only the first and second initial point cloud data that include reflections from the target object, thus providing accurate initial data of the target object for subsequent stitching of the two point cloud data.

[0089] In some feasible implementations, step 2024 can be performed as follows:

[0090] S2024a, Obtain the third reflection intensity unit in the point cloud data of the first target object. The reflection intensity of the third reflection data unit is greater than a second preset reflection intensity threshold.

[0091] S2024b, the point cloud data composed of each third reflection intensity unit is used as the first initial point cloud data.

[0092] Specifically, after acquiring the point cloud data of the first target object, the reflection intensity corresponding to each data unit in the point cloud data of the first target object can be obtained. Since the signal strength of the first object echo signal reflected by the target object transmitted by the data acquisition device is relatively strong, while the signal strength of the second array echo signal is relatively weak, the point cloud data of the first target object obtained after three-dimensional data conversion of the first echo data contains data units with strong reflection intensity and data units with weak reflection intensity. The reflection intensity of each data unit in the point cloud data of the first target object can then be compared with a second preset reflection intensity threshold. If the reflection intensity of a data unit is greater than the second preset reflection intensity threshold, then that data unit can be used as the third reflection intensity unit. The point cloud data composed of the third reflection intensity units is then used as the first initial point cloud data.

[0093] S2024c, Obtain the fourth reflection data unit from the point cloud data of the second target object. The reflection intensity of the fourth reflection data unit is greater than a second preset reflection intensity threshold.

[0094] S2024d, the point cloud data composed of each fourth reflection data unit is used as the second initial point cloud data.

[0095] Specifically, after acquiring the point cloud data of the second target object, the reflection intensity corresponding to each data unit in the point cloud data of the second target object can be obtained. Since the signal strength of the second object echo signal reflected by the target object transmitted by the data acquisition device is relatively strong, while the signal strength of the first array echo signal is relatively weak, the second target object point cloud data obtained after three-dimensional data conversion of the second echo data contains data units with strong reflection intensity and data units with weak reflection intensity. The reflection intensity of each data unit in the second target object point cloud data can then be compared with a second preset reflection intensity threshold. If the reflection intensity of a data unit is greater than the second preset reflection intensity threshold, then that data unit can be used as the fourth reflection intensity unit. The point cloud data composed of the fourth reflection intensity units is then used as the second initial point cloud data.

[0096] In this embodiment, after obtaining the third reflection intensity unit from the first target object point cloud data, the point cloud data composed of each third reflection intensity unit is used as the first initial point cloud data. Similarly, the fourth reflection data unit from the second target object point cloud data is obtained, and the point cloud data composed of each fourth reflection data unit is used as the second initial point cloud data. Since the second preset reflection intensity threshold is a preset reflection intensity threshold that distinguishes between target object reflection and antenna array reflection, the third and fourth reflection data units can be filtered out using the second preset reflection intensity threshold, thereby determining the first and second initial point cloud data. This method is simple, effective, and easy to implement.

[0097] S204, the first initial point cloud data and the second initial point cloud data are corrected using correction parameters to obtain the first target point cloud data and the second target point cloud data; the correction parameters are determined based on the first reflection data and the second reflection data, wherein the first reflection data is obtained by scanning the first reflection reference object with the first antenna array surface, and the second reflection data is obtained by scanning the second reflection reference object with the second antenna array surface. The first reflection reference object is located in the non-antenna area on the second antenna array surface, and the second reflection reference object is located in the non-antenna area on the first antenna array surface.

[0098] It should be noted that, Figure 5 This is a schematic diagram of the calibration parameter scanning environment structure, illustrating an exemplary embodiment of this application. Figure 5 The correction parameters are determined by scanning the intermediate space using the two antenna arrays obtained by scanning the first and second antenna arrays in the absence of a target object.

[0099] Therefore, in some implementations, before step 202, the correction parameters can be determined first, such as... Figure 6 As shown, the method for determining the correction parameters specifically includes:

[0100] S302, acquire the first reflection data and the second reflection data.

[0101] Specifically, when there is no target object between the first antenna array and the second antenna array, the first antenna array scans the first reflecting reference object, and the data acquisition device obtains the first reference object echo signal. This first reference object echo signal is then transmitted to the terminal device for three-dimensional data conversion to obtain the first reflection data. Similarly, the second antenna array scans the second reflecting reference object, and the data acquisition device obtains the second reference object echo signal. This second reference object echo signal is then transmitted to the terminal device for three-dimensional data conversion to obtain the second reflection data.

[0102] The first reflecting reference object is located in the non-antenna area of ​​the second antenna array, and the second reflecting reference object is located in the non-antenna area of ​​the first antenna array. The first reflecting reference object can be located at any position on the first antenna array, such as the upper left, upper right, lower left, or lower right corner, as long as it is within the coverage area of ​​the transmitted signal wave from the first antenna array. The second reflecting reference object can also be located at any position on the first antenna array, such as the upper left, upper right, lower left, or lower right corner, as long as it is within the coverage area of ​​the transmitted signal wave from the second antenna array. Both the first and second reflecting reference objects can include reflective devices such as corner reflectors and sharp metal objects, without limitation. The first and second reflection data are three-dimensional data. The three dimensions of the three-dimensional data represent the width, depth, and height information with the center of the first antenna array or the center of the second antenna array as the origin, respectively. The numerical values ​​of the three-dimensional data represent the reflection intensity of different data units in the spatial position between the first and second antenna arrays. The first reflection data is point cloud data in a coordinate system with the center of the first antenna array as the origin. The second reflection data is point cloud data in a coordinate system with the centroid of the second antenna array as the origin.

[0103] In some alternative implementations, step 302 can be performed as follows:

[0104] S3021, acquire the first initial reflection data and the second initial reflection data. The first initial reflection data is obtained by scanning the first reflection reference object with the first antenna array surface, and the second initial reflection data is obtained by scanning the second reflection reference object with the second antenna array surface.

[0105] It should be noted that different materials have different wave reflection capabilities. The first reflecting reference object is located on the second antenna array. The reflection capability of the first reflecting reference object on the signal waves emitted by the first antenna array is not the same as that of the second antenna array. Therefore, the echo signal from the first reference object can include two echo signals with different signal strengths. Similarly, the second reflecting reference object is located on the first antenna array. The reflection capability of the second reflecting reference object on the signal waves emitted by the second antenna array is not the same as that of the first antenna array. Therefore, the echo signal from the second reference object can also include two echo signals with different signal strengths. The reflection capabilities of the first and second reflecting reference objects are stronger than those of the first and second antenna arrays.

[0106] Specifically, after the data acquisition device sends the echo signals of the first and second reference objects to the terminal device, it can perform three-dimensional data conversion on the first and second reference object echo signals to obtain first initial reflection data and second initial reflection data. The first initial reflection data includes the reflection data of the first reflecting reference object and the reflection data of the second antenna array. The second initial reflection data includes the reflection data of the second reflecting reference object and the reflection data of the first antenna array. Both the first and second initial reflection data are three-dimensional data. The first initial reflection data is point cloud data in a coordinate system with the center of the first antenna array as the origin. The second initial reflection data is point cloud data in a coordinate system with the centroid of the second antenna array as the origin.

[0107] S3022, determine the first reflection data and the second reflection data based on the first initial reflection data, the second initial reflection data and the first preset reflection intensity threshold.

[0108] Specifically, since each data unit in the first and second initial reflection data corresponds to a reflection intensity value, a second preset reflection intensity threshold can be used to filter the data units corresponding to the target object in the first target object point cloud data, thereby determining the first initial point cloud data consisting only of the data units corresponding to the target object. Similarly, the first preset reflection intensity threshold can be used to filter the data units corresponding to the target object in the second target object point cloud data, thereby determining the second initial point cloud data consisting only of the data units corresponding to the target object. The first preset reflection intensity threshold is an empirical value determined by the developers based on multiple experiments and can be adjusted according to actual conditions; no restrictions are imposed here. The first preset reflection intensity threshold can be equal to or unequal to the preset second reflection intensity threshold, depending on the actual situation; no restrictions are imposed here.

[0109] In this embodiment, by acquiring first initial reflection data and second initial reflection data, and based on the first initial reflection data, second initial reflection data, and a first preset reflection intensity threshold, the first reflection data and second initial reflection data are determined. Since the first initial reflection data is obtained by scanning the first reflective reference object with the first antenna array surface, and the second initial reflection data is obtained by scanning the second reflective reference object with the second antenna array surface, the first and second initial reflection data include the reflection data of the target object and the reflection data of the antenna array surface. Therefore, the first preset reflection intensity threshold can be used to determine the first and second initial reflection data corresponding to the target object from the first and second initial reflection data. This method is simple, effective, and easy to implement.

[0110] In some alternative implementations, step 3022 can be performed as follows:

[0111] S3022a, Obtain the first reflection data unit in the first initial reflection data, wherein the reflection intensity of the first reflection data unit is greater than the first preset reflection intensity threshold.

[0112] S3022b, the point cloud data composed of each first reflection data unit is used as the first reflection data;

[0113] Specifically, the reflection intensity of each data unit in the first initial reflection data is obtained, and the reflection intensity of each data unit is compared with a first preset reflection intensity threshold. If the reflection intensity of a data unit is greater than the first preset reflection intensity threshold, then the data unit is identified as the first reflection data unit. The point cloud data composed of the first reflection data units is used as the first reflection data. The comparison of the reflection intensity of each data unit with the first preset reflection intensity threshold can be done by directly comparing the magnitudes. Alternatively, the difference between the reflection intensity of each data unit and the first preset reflection intensity threshold can be calculated, and the difference can be compared with 0. If the difference is greater than 0, then the data unit is identified as the first reflection data unit. Another method is to divide the reflection intensity of each data unit by the first preset reflection intensity threshold, and compare the quotient with 1. If the quotient is greater than 1, then the data unit is identified as the first reflection data unit.

[0114] S3022c, Obtain the second reflection data unit in the second initial reflection data, wherein the reflection intensity of the second reflection data unit is greater than the first preset reflection intensity threshold;

[0115] S3022d uses the point cloud data composed of each second reflection data unit as the second reflection data.

[0116] Specifically, the reflection intensity of each data unit in the second initial reflection data is obtained, and the reflection intensity of each data unit is compared with a first preset reflection intensity threshold. If the reflection intensity of a data unit is greater than the first preset reflection intensity threshold, then the data unit is determined as the second reflection data unit. The point cloud data composed of the second reflection data units is used as the second reflection data.

[0117] In this embodiment, first reflection data units are obtained from the first initial reflection data, and the point cloud data formed by each first reflection data unit is used as the first reflection data. Similarly, second reflection data units are obtained from the second initial reflection data, and the point cloud data formed by each second reflection data unit is used as the second reflection data. Since the reflection intensity of the first reflection data unit is greater than a first preset reflection intensity threshold, and the reflection intensity of the second reflection data unit is also greater than the first preset reflection intensity threshold, the reflection data reflected by the first and second reflection reference objects with stronger reflection capabilities can be filtered out, thus obtaining only the first reflection data corresponding to the first reflection reference object and the second reflection data corresponding to the second reflection reference object. This method is simple and effective, and can provide reflection data between two antenna arrays under ideal conditions, providing a basis for subsequently determining the measurement error of the two antenna arrays.

[0118] S304. Based on the first reflection data, the second reflection data, the nominal coordinates of the first reflection reference object, the nominal coordinates of the second reflection reference object, and the nominal coordinates of the center of the second linear array, determine the correction parameters.

[0119] It should be noted that the nominal coordinates of the first reflective reference object, the nominal coordinates of the second reflective reference object, and the nominal coordinates of the center of the second antenna array are all coordinates that were determined in advance with the center of the first antenna array as the origin.

[0120] Specifically, with the center of the first antenna array as the origin, a first correction parameter between the first and second reflection reference objects can be determined based on the first reflection data and the nominal coordinates of the first reflection reference object. A second correction parameter between the second and first reference objects is determined based on the second reflection data, the nominal coordinates of the second reflection reference object, and the nominal coordinates of the center of the second antenna array.

[0121] Optionally, with the center of the second antenna array as the origin, the nominal coordinates of the first antenna array can be obtained. A first correction parameter between the second and first reflective reference objects can be determined based on the second reflection data and the nominal coordinates of the second reflective reference object. A second correction parameter between the second and first reference objects is determined based on the first reflection data, the nominal coordinates of the first reflective reference object, and the nominal coordinates of the center of the first antenna array.

[0122] In some alternative implementations, step 304 can be performed as follows:

[0123] S3042, Based on the first reflection data and the nominal coordinates of the first reflection reference object, determine the first error between the first antenna array and the second antenna array.

[0124] Specifically, the first reflection data and the nominal coordinates of the first reflection reference are subtracted to obtain the first error between the first antenna array and the second antenna array. For example, the coordinates of the first reflection reference are (x1... s y1 s z1 s The coordinates of the second reflecting reference object are (x2) s y2 s z2 s The nominal coordinates of the center of the second linear array are (x...). b y b , z b The first reflection data is (x1, y1, z1), and the second reflection data is (x2, y2, z2). If there is no measurement error between the first antenna array and the second antenna array, then (x1, y1, z1) = (x1...y1...z1) s y1 s z1 s If there is no measurement error between the first antenna array and the second antenna array, then (Δx1, Δy1, Δz1) = (x1 - x1) / (x2 - x3) / (x4 - x5) / (x6 - x1) / (x2 ... s y1-y1 s ,z1-z1 s ).

[0125] It should be noted that the first reflection data measured with the center of the first antenna array as the origin and the second reflection data measured with the center of the second antenna array as the origin satisfy the following conversion relationship:

[0126] x2=-(x1-x b )

[0127] y2=-(y1-y b )

[0128] z2=z1-z b

[0129] S3044, based on the second reflection data, the nominal coordinates of the second reflection reference object, and the nominal coordinates of the center of the second antenna array, determine the second error between the first antenna array and the second antenna array, and use the first error and the second error as correction parameters.

[0130] Specifically, the second reflection data, the nominal coordinates of the second reflection reference object, and the nominal coordinates of the center of the second antenna array are calculated according to a preset error calculation formula to obtain the second error quantity. The first and second error quantities are used as correction parameters. For example, if there is no measurement error between the first antenna array and the second antenna array, (x2, y2, z2) = (x b -x2 s y b-y2 s z2 s -z b If there is a measurement error between the first antenna array and the second antenna array, then (Δx2, Δy2, Δz2) = (x2 + x2) / ( ... s -x b y2+y2 s -y b z2-z2 s +z b ).

[0131] In this embodiment, a first error between the first antenna array and the second antenna array is determined based on the first reflection data and the nominal coordinates of the first reflection reference. A second error between the first antenna array and the second antenna array is determined based on the second reflection data, the nominal coordinates of the second reflection reference, and the nominal coordinates of the center of the second antenna array. The first and second error values ​​are used as correction parameters to accurately obtain the measurement error between the first and second antenna arrays in the absence of a target object, i.e., the correction parameters. This allows the measurement results to be corrected when scanning a target object.

[0132] In the above embodiments, by acquiring first reflection data and second reflection data, and based on the first reflection data, second reflection data, nominal coordinates of the first reflection reference object, nominal coordinates of the second reflection reference object, and nominal coordinates of the center of the second antenna array, correction parameters are determined. This allows for accurate determination of the measurement error when measuring the first antenna array and the second antenna array, which is then used as correction parameters to correct and stitch together the images of the front and back of the target object after scanning.

[0133] In some alternative implementations, step 204 may be performed as follows:

[0134] S2042, determine the first target point cloud data based on the first initial point cloud data and the first error amount of the correction parameters.

[0135] Specifically, the first initial point cloud data is subtracted from the first error amount of the correction parameter to obtain the first target point cloud data. For example, if the first initial point cloud data is (a, b, c), then the first target point cloud data is (a-Δx1, b-Δy1, c-Δz1).

[0136] S2042, Based on the second initial point cloud data and the second error amount of the correction parameters, determine the reference point cloud data, and perform coordinate transformation on the reference point cloud data to obtain the second target point cloud data.

[0137] Specifically, the reference point cloud data is obtained by subtracting the second error amount of the correction parameters from the second initial point cloud data. For example, if the second initial point cloud data is (A, B, C), then the reference point cloud data is (A-Δx², B-Δy², C-Δz²). Since the second initial point cloud data is measured with the center of the second antenna array as the origin, it needs to be converted to data measured with the center of the first antenna array as the origin. This yields the second target point cloud data.

[0138] In some alternative implementations, step 2042 can be performed as follows:

[0139] Based on a preset coordinate transformation relationship, the reference point cloud data is transformed to obtain the second target point cloud data. The preset coordinate transformation relationship is the mapping relationship between the first antenna array and the second antenna array.

[0140] Specifically, due to the reference point cloud data (x) measured with the center of the first antenna array as the origin... back y back , z back ) and the second target point cloud data (x) measured with the center of the second linear array as the origin. front y front , z front The following transformation relationship is satisfied:

[0141] x back =-(x front -x b )

[0142] y back =-(y front -y b )

[0143] z back =z front -z b ;

[0144] Using the above conversion relationship, the reference point cloud data can be converted into the second target point cloud data.

[0145] In this embodiment, first target point cloud data is determined based on first initial point cloud data and a first error amount of correction parameters; reference point cloud data is determined based on second initial point cloud data and a second error amount of correction parameters; and coordinate transformation is performed on the reference point cloud data to obtain second target point cloud data. This method can correct initial point cloud data of target objects obtained based on different coordinate origins, eliminating measurement errors between the first and second antenna arrays.

[0146] S206, the first target point cloud data and the second target point cloud data are stereo stitched together to obtain a three-dimensional stereo image of the target object.

[0147] Specifically, at this time, both the first target point cloud data and the second target point cloud data are located in a coordinate system with the center of the first antenna array as the origin. By placing the first target point cloud data and the second target point cloud data in the same coordinate system, they are stitched together to form a three-dimensional image of the target object.

[0148] In some alternative implementations, step 206 above can be performed as follows:

[0149] S2062, normalize the first target point cloud data to obtain the first normalized point cloud data, and normalize the second target point cloud data to obtain the second normalized point cloud data.

[0150] Specifically, the first target point cloud data and the second target point cloud data can be divided by a preset normalization threshold to obtain the first normalized point cloud data and the second normalized point cloud data, respectively. Alternatively, the target reflection intensity threshold in the first target point cloud data can be obtained, and the point cloud data of the first target can be divided by the target reflection intensity threshold to obtain the first normalized point cloud data. The target reflection intensity threshold in the second target point cloud data can be obtained, and the point cloud data of the second target can be divided by the target reflection intensity threshold to obtain the first normalized point cloud data.

[0151] In some alternative implementations, step 2062 above can be performed as follows:

[0152] S2062a, obtain the first maximum reflection intensity of the first target point cloud data and the second maximum reflection intensity of the second target point cloud data.

[0153] Specifically, since the first and second target point cloud data include the reflection intensity of each data unit, the maximum first reflection intensity and the maximum second reflection intensity value can be directly obtained from the first and second target point cloud data. That is, the maximum reflection intensity value in the first target point cloud data and the maximum reflection intensity value in the second target point cloud data are selected.

[0154] S2062b, determine the first normalized point cloud data based on the reflection intensity of each data unit in the first target point cloud data and the maximum value of the first reflection intensity.

[0155] Specifically, the reflection intensity of each data unit in the first target point cloud data can be divided by the maximum first reflection intensity to obtain the first normalized point cloud data.

[0156] S2062c, determine the second normalized point cloud data based on the reflection intensity of each data unit and the maximum value of the second reflection intensity in the second target point cloud data.

[0157] Specifically, the reflection intensity of each data unit in the second target point cloud data can be divided by the maximum value of the second reflection intensity to obtain the second normalized point cloud data.

[0158] In this embodiment of the application, by obtaining the first maximum reflection intensity of the first target point cloud data and the second maximum reflection intensity of the second target point cloud data, the first target point cloud data and the second target point cloud data can be normalized to obtain the first normalized point cloud data and the second normalized point cloud data, so that the reflection intensity is evenly distributed between 0 and 1, so that the stitching effect of the first target point cloud data and the second target point cloud data is better.

[0159] S2064, the first normalized point cloud data and the second normalized point cloud data are stereo stitched together to obtain a three-dimensional stereo image of the target object.

[0160] Specifically, by placing the first normalized point cloud data and the second normalized point cloud data in the same coordinate system and stitching them together, a three-dimensional image of the target object can be obtained.

[0161] In some alternative implementations, step 2064 above can be performed as follows:

[0162] The normalized data units in the first and second normalized point cloud data are stitched together in the same coordinate system, and the reflection intensity values ​​corresponding to the normalized data units with the same coordinates are processed to obtain a three-dimensional image of the target object.

[0163] Specifically, by stereo stitching the normalized data units in the first and second normalized point cloud data into the same coordinate system, multiple normalized data units with the same coordinates may correspond to different reflection intensities. Therefore, it is necessary to average or weight the reflection intensities corresponding to the normalized data units with the same coordinates to obtain three-dimensional point cloud data in which each data unit corresponds to a reflection intensity value. This three-dimensional point cloud data constitutes a three-dimensional stereo image of the target object.

[0164] Optionally, after obtaining the three-dimensional image, a preset AI algorithm can be used to detect the target objects in the image.

[0165] To facilitate understanding by those skilled in the art, an example is provided below. (Refer to...) Figure 1As shown, when there is no target object between the first antenna array and the second antenna array, the first antenna array scans the first reflective reference object to obtain the first initial reflection data and the second initial reflection data. The first initial reflection data and the second initial reflection data are compared with the first preset reflection intensity threshold respectively, and the first reflection data (x1, y1, z1) = (100, 100, 100) and the second reflection data (x2, y2, z2) = (90, 110, 90) are selected.

[0166] The coordinates of the center of the second linear array plane, which were determined in advance, are (x b y b , z b ) = (10, 100, 5), the coordinates of the first reflecting reference object are (x1) s y1 s z1 s ) = (95, 100, 100), the coordinates of the second reflecting reference object are (x2) s y2 s z2 s ) = (-95, 5, 90).

[0167] The first error can then be calculated as: (Δx1, Δy1, Δz1) = (x1 - x1) / (Δy1 - Δz1) / (Δx1 - ... s y1-y1 s ,z1-z1 s The second error is: (Δx², Δy², Δz²) = (x² + x²) / (5, 0, 0). s -x b y2+y2 s -y b z2-z2 s +z b ) = (-15, 15, 5).

[0168] Once the target object is positioned between the first and second antenna arrays, the first and second antenna arrays scan the target object to obtain first target object point cloud data and second target object point cloud data. The reflection intensity of each data unit in the first and second target object point cloud data is filtered to determine the first and second initial point cloud data that only include the target object. The first and second initial point cloud data are then corrected using the first and second error values ​​of the correction parameters to obtain the first target point cloud data and reference point cloud data (x). back y back , z back Then, using a preset transformation relationship, the reference point cloud data is converted into the second target point cloud data (x) measured with the center of the second linear array as the origin.front y front , z front Then, the first target point cloud data and the second point cloud data are normalized respectively to obtain first normalized point cloud data and second normalized point cloud data. These are then stitched together with the same coordinate system, and the reflection intensity corresponding to the data units with the same coordinate value is averaged to obtain a three-dimensional image of the target object, such as... Figure 7 As shown.

[0169] In this embodiment, first initial point cloud data obtained by scanning the target object with a first antenna array surface, and second initial point cloud data obtained by scanning the target object with a second antenna array surface, are acquired. Then, correction parameters determined in the absence of a target object are used to correct the first and second initial point cloud data, resulting in first and second target point cloud data. These target point cloud data are then stitched together to obtain a three-dimensional image of the target object. Since the correction parameters are jointly determined based on the first reflection data obtained by scanning the first reflection reference object with the first antenna array surface, and the second reflection data obtained by scanning the second reflection reference object with the second antenna array surface, they can reflect the measurement error between the first and second antenna array surfaces. By using these correction parameters to correct the data obtained after scanning the target object with the two antenna array surfaces, the stitching of the first and second target point cloud data can obtain an accurate three-dimensional image of the target object, allowing personnel to intuitively observe the side profile of the target object.

[0170] It should be understood that although the steps in the flowcharts of the above embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the above embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0171] Based on the same inventive concept, this application also provides a security imaging device for implementing the security imaging method described above. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations in one or more security imaging device embodiments provided below can be found in the limitations of the security imaging method described above, and will not be repeated here.

[0172] Figure 8 This is a schematic diagram of a security inspection imaging device illustrated in an exemplary embodiment of this application. (Refer to...) Figure 8 As shown, the device is used to implement all or part of the functions of the aforementioned method embodiments. Specifically, the security inspection imaging device includes:

[0173] The point cloud acquisition module 602 is used to acquire first initial point cloud data and second initial point cloud data, wherein the first initial point cloud data is obtained by scanning the front of the target object with the first antenna array and the second initial point cloud data is obtained by scanning the back of the target object with the second antenna array.

[0174] The correction module 604 is used to correct the first initial point cloud data and the second initial point cloud data using correction parameters to obtain the first target point cloud data and the second target point cloud data. The correction parameters are determined based on the first reflection data and the second reflection data. The first reflection data is obtained by scanning the first reflection reference object with the first antenna array surface, and the second reflection data is obtained by scanning the second reflection reference object with the second antenna array surface. The first reflection reference object is located in a non-native region on the second antenna array surface, and the second reflection reference object is located in a non-antenna region on the first antenna array surface.

[0175] The stitching module 606 is used to stitch together the first target point cloud data and the second target point cloud data in a three-dimensional manner to obtain a three-dimensional image of the target object.

[0176] The security inspection imaging device provided in this embodiment can execute the above method embodiment, and its implementation principle and technical effect are similar, so it will not be described again here.

[0177] In some alternative implementations, see [link to relevant documentation]. Figure 9 As shown, the security inspection imaging device also includes a calibration parameter determination module 608. Figure 9 This is a schematic diagram illustrating an exemplary embodiment of the security inspection imaging device including a calibration parameter determination module 608. (Refer to...) Figure 9 As shown, in some optional implementations, the calibration parameter determination module 608 specifically includes:

[0178] The reflection data acquisition unit 6081 is used to acquire first reflection data and second reflection data;

[0179] The correction parameter determination unit 6082 is used to determine the correction parameters based on the first reflection data, the second reflection data, the nominal coordinates of the first reflection reference object, the nominal coordinates of the second reflection reference object, and the nominal coordinates of the center of the second linear array.

[0180] In some optional implementations, the correction parameter determination unit 6082 is specifically used to determine the first error between the first antenna array and the second antenna array based on the first reflection data and the nominal coordinates of the first reflection reference object; and to determine the second error between the first antenna array and the second antenna array based on the second reflection data, the nominal coordinates of the second reflection reference object, and the nominal coordinates of the center of the second antenna array, and to use the first error and the second error as correction parameters.

[0181] In some optional implementations, the correction parameter determination unit 6082 is specifically used to acquire first initial reflection data and second initial reflection data; the first initial reflection data is obtained by scanning the first antenna array surface with the first reflection reference object, and the second initial reflection data is obtained by scanning the second antenna array surface with the second reflection reference object; the first initial reflection data and the second initial reflection data are determined based on the first initial reflection data, the second initial reflection data and the first preset reflection intensity threshold.

[0182] In some optional implementations, the correction parameter determination unit 6082 is specifically used to obtain the first reflection data unit in the first initial reflection data, wherein the reflection intensity of the first reflection data unit is greater than the first preset reflection intensity threshold.

[0183] The point cloud data composed of each first reflection data unit is used as the first reflection data; the second reflection data unit in the second initial reflection data is obtained, wherein the reflection intensity of the second reflection data unit is greater than the first preset reflection intensity threshold; the point cloud data composed of each second reflection data unit is used as the second reflection data.

[0184] In some optional implementations, refer to Figure 9 As shown, the correction module 604 includes,

[0185] The first correction unit 6041 is used to determine the first target point cloud data based on the first initial point cloud data and the first error amount of the correction parameters;

[0186] The second correction unit 6042 is used to determine reference point cloud data based on the second initial point cloud data and the second error amount of the correction parameters, and to perform coordinate transformation on the reference point cloud data to obtain the second target point cloud data.

[0187] In some optional implementations, the second correction unit 6042 is specifically used to perform coordinate transformation on the reference point cloud data according to a preset coordinate transformation relationship to obtain the second target point cloud data, wherein the preset coordinate transformation relationship is the mapping relationship between the first antenna array and the second antenna array.

[0188] In some optional implementations, refer to Figure 9 As shown, the splicing module 606 includes:

[0189] The normalization unit 6061 is used to normalize the first target point cloud data to obtain the first normalized point cloud data, and to normalize the second target point cloud data to obtain the second normalized point cloud data.

[0190] The stitching unit 6062 is used to stitch together the first normalized point cloud data and the second normalized point cloud data to obtain a three-dimensional image of the target object.

[0191] In some optional implementations, the normalization unit 6061 is specifically used to obtain the first maximum reflection intensity of the first target point cloud data and the second maximum reflection intensity of the second target point cloud data; determine the first normalized point cloud data based on the reflection intensity of each data unit in the first target point cloud data and the first maximum reflection intensity; and determine the second normalized point cloud data based on the reflection intensity of each data unit in the second target point cloud data and the second maximum reflection intensity.

[0192] In some optional implementations, the stitching unit 6062 is specifically used to stitch together each normalized data unit in the first normalized point cloud data and the second normalized point cloud data into the same coordinate system, and to perform data processing on the reflection intensity values ​​corresponding to the normalized data units with the same coordinates to obtain a three-dimensional stereoscopic image of the target object.

[0193] In some optional implementations, refer to Figure 9 As shown, the point cloud acquisition module 602 includes:

[0194] The point cloud acquisition unit 6021 is used to acquire point cloud data of a first target object and point cloud data of a second target object; wherein, the point cloud data of the first target object is obtained by scanning the target object with the first antenna array, and the point cloud data of the second target object is obtained by scanning the target object with the second antenna array.

[0195] The point cloud determination unit 6022 is used to determine the first initial point cloud data and the second initial point cloud data based on the first target object point cloud data, the second target object point cloud data, and the second preset reflection intensity threshold.

[0196] In some optional implementations, the point cloud determination unit 6022 is specifically used to acquire the third reflection intensity unit in the point cloud data of the first target object; wherein the reflection intensity of the third reflection data unit is greater than the second preset reflection intensity threshold; the point cloud data composed of each third reflection intensity unit is used as the first initial point cloud data; the fourth reflection data unit in the point cloud data of the second target object is acquired; wherein the reflection intensity of the fourth reflection data unit is greater than the second preset reflection intensity threshold; the point cloud data composed of each fourth reflection data unit is used as the second initial point cloud data.

[0197] The security inspection imaging device provided in this embodiment can execute the above method embodiment, and its implementation principle and technical effect are similar, so it will not be described again here.

[0198] Figure 10 This is a schematic diagram illustrating a computer device according to an exemplary embodiment of this application. This application provides a computer device, which may be a terminal device, and its internal structure diagram may be as shown below. Figure 10 As shown, the computer device includes a processor, memory, communication interface, display screen, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, carrier networks, NFC (Near Field Communication), or other technologies. When the computer program is executed by the processor, it implements a security inspection imaging method. The display screen can be an LCD screen or an e-ink screen. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad on the computer device's casing, or an external keyboard, touchpad, or mouse.

[0199] Those skilled in the art will understand that Figure 10 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0200] This application provides a computer device including a memory and a processor. The memory stores a computer program, and the processor executes the steps of the method in any of the above embodiments.

[0201] This application provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the method in any of the above embodiments.

[0202] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties.

[0203] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments described above. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0204] It is readily understood that, based on the several embodiments provided in this application, those skilled in the art can combine, split, or reorganize the embodiments of this application to obtain other embodiments, none of which exceed the protection scope of this application.

[0205] The above detailed embodiments further illustrate the purpose, technical solution, and beneficial effects of the embodiments of this application. It should be understood that the above are merely specific embodiments of the embodiments of this application and are not intended to limit the protection scope of the embodiments of this application. Any modifications, equivalent substitutions, improvements, etc., made on the basis of the technical solutions of the embodiments of this application should be included within the protection scope of the embodiments of this application.

Claims

1. A security inspection imaging method, characterized in that, include: Acquire first initial point cloud data and second initial point cloud data, wherein the first initial point cloud data is obtained by scanning the front of the target object with the first antenna array, and the second initial point cloud data is obtained by scanning the back of the target object with the second antenna array. The first initial point cloud data and the second initial point cloud data are corrected using correction parameters to obtain the first target point cloud data and the second target point cloud data. The correction parameters are determined based on the first reflection data and the second reflection data. The first reflection data is obtained by scanning the first antenna array surface with the first reflection reference object, and the second reflection data is obtained by scanning the second antenna array surface with the second reflection reference object. The first reflection reference object is located in the non-antenna area of ​​the second antenna array surface, and the second reflection reference object is located in the non-antenna area of ​​the first antenna array surface. A three-dimensional image of the target object is obtained by stereo stitching the first target point cloud data and the second target point cloud data. The method for determining the correction parameters includes: Based on the first reflection data and the nominal coordinates of the first reflection reference object, determine the first error between the first antenna array and the second antenna array; Based on the second reflection data, the nominal coordinates of the second reflection reference object, and the nominal coordinates of the center of the second antenna array, a second error between the first antenna array and the second antenna array is determined, and the first error and the second error are used as the correction parameters.

2. The security inspection imaging method according to claim 1, characterized in that, The method for determining the correction parameters also includes: The first reflection data unit in the first initial reflection data is obtained, and the point cloud data composed of each first reflection data unit is used as the first reflection data; wherein, the first initial reflection data is obtained by scanning the first reflection reference object with the first antenna array surface; the reflection intensity of the first reflection data unit is greater than the first preset reflection intensity threshold. The second reflection data unit in the second initial reflection data is obtained, and the point cloud data composed of each second reflection data unit is used as the second reflection data; wherein, the second initial reflection data is obtained by scanning the second reflection reference object with the second antenna array surface; the reflection intensity of the second reflection data unit is greater than the first preset reflection intensity threshold.

3. The security inspection imaging method according to claim 2, characterized in that, The step of correcting the first initial point cloud data and the second initial point cloud data using correction parameters to obtain the first target point cloud data and the second target point cloud data includes: The first target point cloud data is determined based on the first initial point cloud data and the first error amount of the correction parameter; Based on the second initial point cloud data and the second error amount of the correction parameters, the reference point cloud data is determined; According to a preset coordinate transformation relationship, the reference point cloud data is transformed to obtain the second target point cloud data, wherein the preset coordinate transformation relationship is a mapping relationship between the first antenna array and the second antenna array.

4. The security inspection imaging method according to claim 2, characterized in that, The step of stereoscopically stitching the first target point cloud data and the second target point cloud data to obtain a three-dimensional stereoscopic image of the target object includes: The first target point cloud data is normalized to obtain the first normalized point cloud data, and the second target point cloud data is normalized to obtain the second normalized point cloud data. The first normalized point cloud data and the second normalized point cloud data are stitched together in a stereoscopic manner to obtain a three-dimensional stereoscopic image of the target object.

5. The security inspection imaging method according to claim 4, characterized in that, The process of normalizing the first target point cloud data to obtain first normalized point cloud data, and normalizing the second target point cloud data to obtain second normalized point cloud data, includes: Obtain the first maximum reflection intensity of the first target point cloud data and the second maximum reflection intensity of the second target point cloud data; The first normalized point cloud data is determined based on the reflection intensity of each data unit in the first target point cloud data and the maximum value of the first reflection intensity. The second normalized point cloud data is determined based on the reflection intensity of each data unit in the second target point cloud data and the maximum value of the second reflection intensity.

6. The security inspection imaging method according to claim 5, characterized in that, The step of stereo stitching the first normalized point cloud data and the second normalized point cloud data to obtain a three-dimensional stereo image of the target object includes: The normalized data units in the first and second normalized point cloud data are stitched together in the same coordinate system using a 3D stitching method. The reflection intensity values ​​corresponding to the normalized data units with the same coordinates are processed to obtain a three-dimensional image of the target object.

7. The security inspection imaging method according to claim 1, characterized in that, The acquisition of the first initial point cloud data and the second initial point cloud data includes: Acquire point cloud data of a first target object and point cloud data of a second target object; wherein, the first target object point cloud data is obtained by scanning the front of the target object with the first antenna array facing it, and the second target object point cloud data is obtained by scanning the back of the target object with the second antenna array facing it. Obtain the third reflection intensity unit in the point cloud data of the first target object; wherein the reflection intensity of the third reflection data unit is greater than the second preset reflection intensity threshold; The point cloud data composed of each of the third reflection intensity units is used as the first initial point cloud data; Obtain the fourth reflection data unit in the point cloud data of the second target object; wherein the reflection intensity of the fourth reflection data unit is greater than the second preset reflection intensity threshold. The point cloud data composed of each of the fourth reflection data units is used as the second initial point cloud data.

8. A security inspection imaging device, characterized in that, include: The point cloud acquisition module is used to acquire first initial point cloud data and second initial point cloud data, wherein the first initial point cloud data is obtained by scanning the front of the target object with the first antenna array, and the second initial point cloud data is obtained by scanning the back of the target object with the second antenna array. The correction module is used to correct the first initial point cloud data and the second initial point cloud data using correction parameters to obtain the first target point cloud data and the second target point cloud data. The correction parameters are determined based on the first reflection data and the second reflection data. The first reflection data is obtained by scanning the first antenna array surface with a first reflection reference object, and the second reflection data is obtained by scanning the second antenna array surface with a second reflection reference object. The first reflection reference object is located in the non-antenna region of the second antenna array surface, and the second reflection reference object is located in the non-antenna region of the first antenna array surface. The stitching module is used to stitch the first target point cloud data and the second target point cloud data together in a three-dimensional manner to obtain a three-dimensional image of the target object. The method for determining the correction parameters includes: Based on the first reflection data and the nominal coordinates of the first reflection reference object, determine the first error between the first antenna array and the second antenna array; Based on the second reflection data, the nominal coordinates of the second reflection reference object, and the nominal coordinates of the center of the second antenna array, a second error between the first antenna array and the second antenna array is determined, and the first error and the second error are used as the correction parameters.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 7.

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