Millimeter-wave human body security inspection system and method based on double standing postures

Abstract

The present disclosure provides a millimeter-wave human body security inspection method and system based on double postures. The method includes: using a millimeter-wave human body security inspection device to scan and inspect the body of an inspected person in a first posture to obtain a first millimeter-wave human body image; using the millimeter-wave human body security inspection device to scan and inspect the body of the same inspected person in a second posture to obtain a second millimeter-wave human body image, where the second posture is different from the first posture; and determining whether the inspected person is carrying contraband based on at least both the first millimeter-wave human body image and the second millimeter-wave human body image.

Description

Technical Field

[0001] Embodiments of the present disclosure generally relate to the field of security inspection, and in particular, to a system and method for millimeter-wave human body security inspection based on dual postures. Background Art

[0002] To ensure public safety, security inspection in important public places is a necessary means. Currently, the most widely used imaging security inspection technologies are mainly X-ray imaging technology and millimeter-wave imaging technology. Millimeter-wave detection imaging technology has many advantages, such as not causing harm to the human body during use because it is non-ionizing radiation, being able to penetrate human clothing, and identifying various metal and non-metal prohibited items. In recent years, with the development of millimeter-wave technology and the reduction of device costs, millimeter-wave imaging has begun to be widely used in the field of human body security inspection.

[0003] When using a millimeter-wave device for human body security inspection, due to the limitation of the length of the detection array, only the area directly facing the scanning plane can obtain high-quality images, and problems such as a decrease in image quality will occur at positions such as the sides of the body, affecting the detection efficiency. In addition, if a thin sheet-shaped item is placed perpendicular to the scanning plane, its image will be invisible due to the limitation of the imaging angle. These problems will affect the efficiency and accuracy of security inspection under specific environmental conditions. Summary of the Invention

[0004] To overcome at least one of the above and other problems and defects existing in the prior art, the present disclosure is proposed.

[0005] According to one aspect of the present disclosure, a millimeter-wave human body security inspection method based on dual postures is proposed, including: using a millimeter-wave human body security inspection device to scan and inspect the body of an inspected person in a first posture to obtain a first millimeter-wave human body image; using the millimeter-wave human body security inspection device to scan and inspect the body of the same inspected person in a second posture to obtain a second millimeter-wave human body image, where the second posture is different from the first posture; and determining whether the inspected person is carrying prohibited items based on at least both the first millimeter-wave human body image and the second millimeter-wave human body image.

[0006] In some embodiments, the millimeter-wave human body security inspection device has a scanning plane for scanning the body of the inspected person, and the method further includes: guiding the first posture and the second posture of the inspected person so that at least part of the part of the body of the inspected person scanned by the scanning plane when in the first posture is complementary to the part of the body of the inspected person scanned by the scanning plane when in the second posture, and the combination of the obtained first millimeter-wave human body image and the second millimeter-wave human body image forms a substantially complete contour image of the body of the inspected person.

[0007] In some embodiments, the first standing posture and the second standing posture are selected such that the combination of the first millimeter-wave human body image and the second millimeter-wave human body image includes at least images of the front and side of the body of the person to be inspected, the armpits, the inner and outer sides of the thighs, and the inner side of the arms.

[0008] In some embodiments, the millimeter-wave human body security scanner has a scanning surface for scanning the body of the person to be inspected, and the method further includes: guiding or instructing the person to be inspected to stand at a designated security inspection position in the first standing posture, such that the front or back of the body of the person to be inspected faces the scanning surface; and / or, guiding or instructing the person to be inspected to stand at the designated security inspection position in the second standing posture, such that the side of the body of the person to be inspected faces the scanning surface.

[0009] In some embodiments, at least one of voice prompt and visual prompt is used by a guiding device to guide or instruct the person to be inspected to stand at the designated security inspection position in the first standing posture or the second standing posture.

[0010] In some embodiments, the method further includes: determining whether the first standing posture of the person to be inspected meets the requirements of the first designated standing posture; and / or determining whether the second standing posture of the person to be inspected meets the requirements of the second designated standing posture;

[0011] In some embodiments, before using the millimeter-wave human body security scanner to scan and inspect the body of the person to be inspected in the first standing posture, it is determined whether the first standing posture of the person to be inspected meets the requirements of the first designated standing posture; and / or, before using the millimeter-wave human body security scanner to scan and inspect the body of the person to be inspected in the second standing posture, it is determined whether the second standing posture of the person to be inspected meets the requirements of the second designated standing posture.

[0012] In some embodiments, "determining whether the first standing posture of the person to be inspected meets the requirements of the first designated standing posture" includes: obtaining a first visible light image of the body of the person to be inspected in the first standing posture, and determining whether the first standing posture of the person to be inspected meets the requirements of the first designated standing posture based on the first visible light image; and / or, "determining whether the first standing posture of the person to be inspected meets the requirements of the first designated standing posture" includes: obtaining a second visible light image of the body of the person to be inspected in the second standing posture, and determining whether the second standing posture of the person to be inspected meets the requirements of the second designated standing posture based on the second visible light image.

[0013] In some embodiments, it is determined whether the first standing posture of the person to be inspected meets the requirements of the first designated standing posture based on the first millimeter-wave human body image; and / or it is determined whether the second standing posture of the person to be inspected meets the requirements of the second designated standing posture based on the second millimeter-wave human body image.

[0014] According to an embodiment of another aspect of the present disclosure, there is provided a millimeter-wave human body security inspection system based on a dual standing posture, including:

[0015] A millimeter-wave human body security scanner, which is configured to:

[0016] Scan the body of the person to be inspected in the first standing posture to obtain a first millimeter-wave human body image, and

[0017] Scan the body of the same person to be inspected in the second standing posture to obtain a second millimeter-wave human body image, where the second standing posture is different from the first standing posture; and

[0018] A processor, which communicates with the millimeter-wave human body security scanner and is configured to determine whether the person to be inspected is carrying prohibited items based on at least both the first millimeter-wave human body image and the second millimeter-wave human body image.

[0019] In some embodiments, the millimeter-wave human body security scanner has a scanning surface for scanning the body of the person to be inspected, and the millimeter-wave human body security system is configured to guide the first standing posture and the second standing posture of the person to be inspected, so that the part of the body of the person to be inspected scanned by the scanning surface when in the first standing posture and the part of the body of the person to be inspected scanned by the scanning surface when in the second standing posture are at least partially complementary, whereby the combination of the first millimeter-wave human body image and the second millimeter-wave human body image obtained by scanning with the millimeter-wave human body security scanner forms a substantially complete contour image of the body of the person to be inspected.

[0020] In some embodiments, the millimeter-wave human body security system is configured such that the first standing posture and the second standing posture are such that the combination of the first millimeter-wave human body image and the second millimeter-wave human body image obtained by scanning with the millimeter-wave human body security scanner at least includes images of the front and side of the body of the person to be inspected, the armpits, the inner and outer thighs, and the inner arms.

[0021] In some embodiments, the millimeter-wave human body security scanner has a scanning surface for scanning the body of the person to be inspected, and the millimeter-wave human body security system further includes a guiding device, which is configured to: guide or instruct the person to be inspected to stand at a designated security inspection position in the first standing posture, so that the front or back of the body of the person to be inspected faces the scanning surface; and / or guide or instruct the person to be inspected to stand at a designated security inspection position in the second standing posture, so that the side of the body of the person to be inspected faces the scanning surface.

[0022] In some embodiments, the guiding device is configured to guide or instruct the person to be inspected to stand at a designated security inspection position in the first standing posture or the second standing posture by at least one of voice prompts and visual prompts.

[0023] In some embodiments, the guiding device includes: a voice prompt device configured to prompt the person to be inspected to stand at a designated security inspection position in a first standing posture or a second standing posture by voice; and / or a display device disposed near the millimeter-wave human body security inspection device and visible to the person to be inspected, and the display device is configured to prompt the person to be inspected to stand at the designated security inspection position in a first standing posture or a second standing posture visually.

[0024] In some embodiments, the processor is further configured to: determine whether the first standing posture of the person to be inspected meets the requirements of a first designated standing posture; and / or determine whether the second standing posture of the person to be inspected meets the requirements of a second designated standing posture.

[0025] In some embodiments, the processor is further configured to: determine whether the first standing posture of the person to be inspected meets the requirements of the first designated standing posture before the millimeter-wave human body security inspection device scans the body of the person to be inspected in the first standing posture; and / or determine whether the second standing posture of the person to be inspected meets the requirements of the second designated standing posture before the millimeter-wave human body security inspection device scans the body of the person to be inspected in the second standing posture.

[0026] In some embodiments, the millimeter-wave human body security inspection system further includes a photographing device configured to obtain a first visible light image of the body of the person to be inspected in the first standing posture and obtain a second visible light image of the body of the person to be inspected in the second standing posture; the processor is further configured to: determine whether the first standing posture of the person to be inspected meets the requirements of the first designated standing posture based on the first visible light image; and / or determine whether the second standing posture of the person to be inspected meets the requirements of the second designated standing posture based on the second visible light image.

[0027] In some embodiments, the processor is further configured to: determine whether the first standing posture of the person to be inspected meets the requirements of the first designated standing posture based on the first millimeter-wave human body image; and / or determine whether the second standing posture of the person to be inspected meets the requirements of the second designated standing posture based on the second millimeter-wave human body image.

[0028] Other objects and advantages of the present disclosure will become apparent from the following detailed description of the present disclosure with reference to the accompanying drawings, and will help to provide a comprehensive understanding of the present disclosure. Description of the Drawings

[0029] The features and advantages of the present disclosure can be more clearly understood by referring to the accompanying drawings. The drawings are schematic and should not be construed as imposing any limitation on the present disclosure. In the drawings:

[0030] Figure 1 It is a schematic diagram showing the layout of a millimeter-wave human body security inspection system according to an exemplary embodiment of the present disclosure;

[0031] Figure 2 Schematic diagram showing a first designated standing posture for a person to be inspected according to an exemplary embodiment of the present disclosure;

[0032] Figure 3 Schematic diagram showing a second designated standing posture for a person to be inspected according to an exemplary embodiment of the present disclosure;

[0033] Figure 4 Schematic diagram showing the distribution of key points for identifying the first standing posture of a person to be inspected according to an exemplary embodiment of the present disclosure;

[0034] Figure 5 Flowchart showing a millimeter-wave human body security inspection method according to an embodiment of the present disclosure; and

[0035] Figure 6 Flowchart showing a millimeter-wave human body security inspection method according to an example of the present disclosure. Detailed implementation manners

[0036] Next, the technical solutions in the embodiments of the present disclosure will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present disclosure.

[0037] In addition, in the following detailed description, for the sake of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is obvious that one or more embodiments can also be implemented without these specific details. In other cases, well-known structures and devices are shown in a schematic manner to simplify the drawings.

[0038] Figure 1 Schematically shows the layout of a human body security inspection system according to an exemplary embodiment of the present disclosure. As shown in the figure, the security inspection system includes a human body imaging device, such as a millimeter-wave human body security inspection instrument 100, which is used to scan and inspect the body of a person to be inspected to obtain a millimeter-wave human body image or corresponding scan data. For example, the millimeter-wave human body security inspection instrument can be based on passive or passive millimeter-wave imaging technology, and realizes imaging by collecting the millimeter-wave radiation of the target itself or by collecting the millimeter-wave reflected or scattered by the target. Exemplarily, the millimeter-wave human body security inspection instrument can include a millimeter-wave transceiver device, such as a millimeter-wave antenna array for transmitting and receiving millimeter-wave signals and a millimeter-wave transceiver associated with the millimeter-wave antenna array.

[0039] Millimeter-wave human body security scanners can be divided into columnar scanning systems, planar scanning systems, and area array scanning systems. In the illustrated embodiment, the millimeter-wave human body security scanner 100 is in the form of a security door that defines an inspection passage. The person to be inspected stands at a designated position within the inspection passage in a proper standing posture to receive security inspection. For example, the millimeter-wave human body security scanner can include a linear array planar up-and-down scanning security door, a linear array planar left-and-right scanning security door, a broken-line array up-and-down scanning security door, or a linear array turntable rotating security door, an arc or cylindrical surface scanning security door. Correspondingly, the millimeter-wave human body security scanner can have different forms of scanning surfaces for scanning the body of the person to be inspected, such as the planar array scanning surface 110 illustrated in the figure.

[0040] According to an embodiment of the present disclosure, a millimeter-wave human body security scanner can be used to scan and inspect the body of the same person to be inspected in different standing postures (for example, at least two standing postures), reducing or avoiding the problem of mutual occlusion between different parts of the human body, improving the accuracy of detecting prohibited items carried during human body security inspection, reducing false negatives, and at the same time improving the security inspection efficiency of the device. Exemplarily, the millimeter-wave human body security scanner can be configured to scan and inspect the body of the same person to be inspected in a first standing posture and a second standing posture that are different from each other, so as to obtain a first millimeter-wave human body image and a second millimeter-wave human body image respectively.

[0041] The human body security inspection system further includes a processor 200, such as a data or image processing device, which communicates with the millimeter-wave human body security scanner 100, receives scanning data or millimeter-wave human body images from the millimeter-wave human body security scanner, and is capable of determining whether the person to be inspected is carrying a prohibited item based at least on a combination of different millimeter-wave human body images of the same person to be inspected in different standing postures, for example, based at least on both the first millimeter-wave human body image and the second millimeter-wave human body image, and outputs the results obtained from different standing postures after comprehensive processing. The comprehensive processing can include denoising, combining duplicate results, etc.

[0042] The human body security inspection system can further include a display device for displaying security inspection images and / or the determination results of the processor 200. For example, in the illustrated embodiment, the human body security inspection system can include at least one of a device-side security inspection image display device 300 and an operator-side security inspection image display device 400 that communicates with the processor 200, so that the operator can view and process the security inspection results, such as allowing the person to be inspected to pass, or guiding the person to be inspected suspected of carrying a prohibited item to receive further inspection. These display devices can be set separately, or can be integrated into a central control room or an operation console.

[0043] In multiple embodiments according to the present disclosure, different standing postures of the same person to be inspected can be selected such that the portions of the person's body scanned by the scanning surface when in different standing postures are at least partially complementary. For example, the portion of the person's body scanned by the scanning surface 110 when in the first standing posture is at least partially complementary to the portion of the person's body scanned by the scanning surface 110 when in the second standing posture. As a result, a combined image of different millimeter-wave human body images of the same person to be inspected obtained by scanning with a millimeter-wave human body security scanner when in different standing postures can form a substantially complete contour image of the person's body, improving the imaging quality.

[0044] For example, different standing postures of the same person to be inspected are selected or specified such that the scanning surface scans a first portion of the person's body when in the first standing posture, and scans a second portion when in a second standing posture different from the first standing posture. The second portion includes portions with poor imaging quality when scanning the person in the first standing posture, that is, the second portion is at least partially different from the first portion and is effectively scanned separately. In this way, high-quality images can be obtained, improving the detection accuracy. For example, different standing postures of the person to be inspected can be selected or specified such that the combined image of different millimeter-wave human body images of the same person to be inspected obtained by scanning with a millimeter-wave human body security scanner when in different standing postures at least includes images of the front and side of the person's body, the armpits, the inner and outer thighs, and the inner arms.

[0045] In some examples, the human body security inspection system is set with different designated standing postures, and guides the person to be inspected to stand for the scanning inspection in a standing posture substantially conforming to the designated standing posture. Figure 2 An exemplary first designated standing posture is shown, where (a) shows a front view of the person to be inspected in the first designated standing posture, and (b) shows a rear view of the person to be inspected in the first designated standing posture. In Figure 2 the first designated standing posture illustrated, the person's body faces the scanning surface of the millimeter-wave human body security scanner or its security door with the front and / or rear, stands with the legs apart, and the arms are spread away from the body trunk, such as forming a substantially "m" shape with the body trunk, to expose the inner arms and armpit areas for scanning inspection. Figure 3 An exemplary second designated standing posture is shown, where (a) shows a right side view of the person to be inspected in the second designated standing posture, and (b) shows a left side view of the person to be inspected in the second designated standing posture. In Figure 3 the second designated standing posture illustrated, the person's body faces the scanning surface of the millimeter-wave human body security scanner or its security door with the side, stands with the legs apart, such as separated front and back, so that the inner sides of the legs are exposed, and the arms are spread away from the body trunk, such as the arms extending in different directions, to expose the inner arms and / or armpit areas for scanning inspection. It will be understood that Figure 2 and 3The specified standing postures shown are merely illustrative. The human body security inspection system according to an embodiment of the present disclosure may also guide the person to be inspected to accept security inspection in other suitable and at least partially complementary different standing postures.

[0046] In addition to or instead of the manual guidance mode in which an operator guides the person to be inspected to stand at the specified security inspection position in a standing posture that is substantially consistent with or conforms to the specified standing posture, the human body security inspection system according to an embodiment of the present disclosure may include a guiding device for guiding the person to be inspected to stand at the specified security inspection position in a standing posture that is substantially consistent with or conforms to the specified standing posture to accept security inspection. As an example, the guiding device may guide or instruct the person to be inspected to stand at the specified security inspection position in a first standing posture that is substantially consistent with or conforms to the first specified standing posture, such that the front or back of the person's body faces the scanning surface of the security inspection instrument, and / or guide or instruct the person to be inspected to stand at the specified security inspection position in a second standing posture that is substantially consistent with or conforms to the second specified standing posture, such that the side of the person's body faces the scanning surface.

[0047] Exemplarily, the guiding device may guide or instruct the person to be inspected to stand at the specified security inspection position in a standing posture that is substantially consistent with or conforms to the specified standing posture by means of voice prompts and / or visual prompts. For example, as Figure 1 shown, the guiding device may include a voice prompt device 510 and / or a display device 520. The voice prompt device 510 may be, for example, a speaker for prompting the person to be inspected to stand at the specified security inspection position in a standing posture that is substantially consistent with or conforms to the specified standing posture by voice or audio information (such as playing a prompt sound), while the display device 520 may be, for example, a display screen or an indicator for prompting the person to be inspected to stand at the specified security inspection position in a standing posture that is substantially consistent with or conforms to the specified standing posture visually (such as pictures, animations, texts, etc.). The display device 520 may be arranged near the millimeter-wave human body security inspection instrument to be visible to the person to be inspected, such as near the entrance of the inspection passage.

[0048] In an embodiment of the present disclosure, the human body security inspection system guides the person to be inspected to accept a scanning inspection in a standing posture that is substantially consistent with the specified standing posture. For this purpose, it may be determined in a manual or automatic mode whether the standing posture of the person to be inspected meets the requirements of the specified standing posture. In the manual mode, an operator may visually determine whether the standing posture of the person to be inspected is substantially consistent with or conforms to the specified standing posture based on the standing posture of the person to be inspected at the specified inspection position itself or based on an image of the person's standing posture. As a replacement or supplement, it may also be determined in an automatic mode, for example, by means of a processor, whether the standing posture of the person to be inspected meets the requirements of the specified standing posture; exemplarily, the processor may determine whether the standing posture meets the requirements of the specified standing posture based on images of the person's body in different standing postures.

[0049] For example, before a millimeter-wave human body security scanner scans the body of a person being inspected in a standing posture, it can be determined whether the standing posture of the person being inspected meets the requirements of the specified standing posture. As an example, the criteria for determination can include whether different standing postures of the same person being inspected or the scanned parts of different standing postures are complementary, and whether different standing postures of the same person being inspected can ensure that body parts with slightly poor imaging quality in a routine inspection (such as the sides of the torso, armpits, inner arms, inner and outer sides of the legs, etc., and even including the soles of the feet) are scanned and clearly imaged.

[0050] As Figure 1 shown, the human body security inspection system may further include a photographing device 600, which is used to acquire visible light images of the body of the person being inspected in different standing postures. The photographing device 600 can communicate with the processor 200, and the processor 200 can determine whether the standing posture of the person being inspected meets the requirements of the specified standing posture based on the visible light images of the body of the person being inspected in different standing postures; if so, it can be determined that the standing posture of the person being inspected conforms to the specified standing posture. At this time, the determination result can be automatically fed back to the security scanner, and the security scanner can start the scanning inspection based on this; if not, the system can feed back the determination result to the person being inspected and / or the operator (such as via a guiding device or via the display device 300 or 400). The photographing device 600 can also communicate with the display device 300 or 400 to display the acquired visible light images of the body of the person being inspected on the display device 300 or 400, and the operator can manually determine whether the standing posture of the person being inspected meets the requirements of the specified standing posture.

[0051] In some embodiments, the operator or the processor 200 can determine whether the standing posture of the person being inspected meets the requirements of the specified standing posture based on the obtained millimeter-wave human body image; if so, the person being inspected is guided to accept the security inspection in the next standing posture or end the inspection; if not, the person being inspected is guided to change the standing posture until it conforms to the specified standing posture.

[0052] There are various ways to determine whether the standing posture of the person being inspected is correct or meets the requirements of the specified standing posture based on the image of the person being inspected. For example, it can be determined whether the difference (such as the graphic boundary difference) between the doll image corresponding to the specified standing posture and the visible light image is within a predetermined threshold range. The following will describe this by taking the method of determining whether the standing posture is correct or meets the requirements of the specified standing posture based on the key points on the human body as an example.

[0053] Exemplarily, the coordinates of multiple key points on the human body can be determined, and then a comprehensive judgment can be made according to the coordinate relationship between the key points. For example, as Figure 4 shown, when the person being inspected is in Figure 2When the standing posture shown in the figure is scanned, multiple key points on the human body include but are not limited to: 1. The top of the head; 2. The left shoulder; 3. The right shoulder; 4. The cervical vertebra; 5. The midpoint of the lower back (for the back image); 6. The left elbow; 7. The right elbow; 8. The left wrist; 9. The right wrist; 10. The left fingertips; 11. The right fingertips; 12. The left armpit; 13. The right armpit; 14. The left hip; 15. The right hip; 16. The navel (for the front image); 17. The crotch bottom point; 18. The starting point of the left groin; 19. The starting point of the right groin; 20. The left knee; 21. The right knee; 22. The left ankle; 23. The right ankle; 24. The left sole of the foot; 25. The right sole of the foot. The coordinate system can take the upper left vertex of the original image as the origin, with the positive x-axis direction horizontally to the right and the positive y-axis direction vertically downward. In practice, according to the projection characteristics of the original data in different directions, combined with methods such as regression analysis to obtain the coordinates of the specified points, or the operator or the device marks the key points in the obtained image according to experience. After obtaining the coordinates of the specified points, the corresponding data can be processed according to the following steps, and it can be judged whether the standing posture of the person being examined is correct. The processing methods for the front and back (back) are similar, and the relationships of some points can be adjusted according to the front-back (back) correspondence relationship:

[0054] Step 1: Calculate the midpoint between the left shoulder and the right shoulder, the midpoint between the left hip and the right hip, and the midpoint between the left knee and the right knee;

[0055] Step 2: According to the coordinates of the left and right fingertips, left and right wrists, left and right elbows, and left and right shoulders, calculate the angles between the left upper arm, left lower arm, right upper arm, and right lower arm and the horizontal direction respectively. These four angles are defined as ∠A, ∠B, ∠C, and ∠D; calculate the angles between the cervical vertebra point and the lines connecting the left and right shoulder points and the horizontal direction. These two angles are defined as ∠E and ∠F; all angles are positive values;

[0056] Step 3: According to the calculation results in Step 1 and 2, check whether the image meets the following requirements:

[0057] a. Whether the three midpoints calculated in Step 1, the top of the head point, the midpoint of the lower back or the navel fall within the area near the horizontal central axis of the image;

[0058] b. Whether the abscissas of each point meet:

[0059] (1) Left wrist ≤ left elbow < left shoulder < cervical vertebra < right shoulder < right elbow ≤ right wrist;

[0060] (2) Left fingertips ≤ left elbow < left armpit < cervical vertebra < right armpit < right elbow ≤ right fingertips:

[0061] (3) Left elbow < left hip < midpoint of the lower back < right hip < right elbow;

[0062] (4) Left ankle ≤ left knee < crotch bottom point < right knee ≤ right ankle;

[0063] (5) The left sole of the foot < the right sole of the foot;

[0064] c. Whether the vertical coordinates of each point satisfy:

[0065] (1) The vertical coordinate of the top of the head is the smallest, i.e., the height is the highest; the vertical coordinates of the left and right soles of the feet are the largest, i.e., the height is the lowest;

[0066] (2) Left shoulder ≤ left elbow < left wrist < left fingertip; right shoulder ≤ right elbow < right wrist < right fingertip;

[0067] (3) Left shoulder < left armpit < midpoint of the lower back < left hip < crotch bottom point; right shoulder < right armpit < midpoint of the right waist < right hip < crotch bottom point;

[0068] (4) Crotch bottom point < left knee < left ankle < left sole of the foot; crotch bottom point < right knee < right ankle < right sole of the foot;

[0069] d. ∠A < ∠B; ∠C < ∠D;

[0070] e. ∠E ≤ 20°; ∠F ≤ 20°;

[0071] f. The positional relationships between the remaining points conform to the normal human body shape.

[0072] When the image meets all the conditions in step 3, it can be determined that the scanning standing posture corresponding to the image is correct or meets the requirements of the specified standing posture. Otherwise, it is determined that the scanning standing posture is incorrect, and the corresponding result is output.

[0073] When the person being examined undergoes a scanning examination in the Figure 3 standing posture shown in the figure, multiple key points on the human body are schematically shown as black dots in the figure, including but not limited to: the top of the head; the starting point of the left arm; the left elbow; the left wrist; the left fingertip; the starting point of the right arm; the right elbow; the right wrist; the right fingertip; the midpoint of the waist; the front waist; the lower back; the starting point of the left thigh; the starting point of the right thigh; the left knee; the right knee; the left ankle; the right ankle; the left sole of the foot; the right sole of the foot. The coordinate system in the scanned image can be the same as that of the Figure 2 scanned image of the standing posture. The image with the person facing the right side can be defined as the front image, and the image with the person facing the left side can be defined as the reverse image. The following uses the front image as an example to elaborate on the standing posture judgment criteria. The criteria for processing the reverse image are based on the coordinate relationship corresponding to the front face:

[0074] Step 1': According to the coordinates of the starting point of the arm, the elbow point, and the wrist, calculate the angles between the left upper arm, the left lower arm, the right upper arm, and the right lower arm and the horizontal direction respectively. These four angles are defined as ∠A, ∠B, ∠C, and ∠D; in addition, calculate the angles between the left upper arm and the left lower arm, and between the right upper arm and the right lower arm. These two angles are defined as ∠E and ∠F; all angles are positive values;

[0075] Step 2': According to the calculation results in Step 1' and the coordinates of each point, check whether the image meets the following requirements:

[0076] a. Whether the abscissas of each point satisfy:

[0077] (1) Left arm starting point < left elbow < left wrist < left fingertip; Right arm starting point < right elbow < right wrist < right fingertip;

[0078] (2) Top of head < right elbow; Top of head < left elbow; Lower back < top of head < front waist; Right thigh starting point < top of head < left thigh starting point; Right knee < top of head < left knee; Right ankle < top of head < left ankle; Right sole < top of head < left sole;

[0079] (3) Lower back < left arm starting point, right arm starting point, waist key point < front waist; Right thigh starting point < left arm starting point, right arm starting point, waist key point < left thigh starting point; Right knee < left arm starting point, right arm starting point, waist key point < left knee; Right ankle < left arm starting point, right arm starting point, waist key point < left ankle; Right sole < left arm starting point, right arm starting point, waist key point < left sole;

[0080] (4) Left fingertip < right fingertip;

[0081] (5) Right ankle ≤ right knee < right thigh starting point; Left thigh starting point < left knee ≤ left ankle;

[0082] b. The ordinates of each point satisfy:

[0083] (1) The top of the head is the highest point except for the left fingertip and the left wrist, that is, left fingertip < left wrist < top of the head < other points; The left and right sole points are the lowest points, that is, left and right soles > other points;

[0084] (2) Left fingertip < left wrist < left elbow < left arm starting point; Right fingertip ≤ right wrist ≤ right elbow ≤ right arm starting point; Left elbow < right fingertip;

[0085] (3) Left and right upper arm starting points < front waist, lower back, waist midpoint < left and right thigh starting points < left and right knees < left and right ankles < left and right soles;

[0086] c. 30° ≤ ∠A ≤ 60°; 30° ≤ ∠B ≤ 60°;

[0087] d. ∠C ≤ 10°; ∠D ≤ 10°;

[0088] e. ∠E ≤ 20°; ∠F ≤ 20°;

[0089] f. The positional relationships between the remaining points conform to the normal human body form.

[0090] When the image meets all the conditions in step 2', it is determined that the scanning stance of the frontal image is correct; otherwise, it is determined that the scanning stance is incorrect, and the corresponding result is output. As some examples, the final stance judgment result can be comprehensively given by the results of the front and back images. For example, when the precise requirement is that only when both the front and back images give the conclusion of "correct stance", the relevant prompt of "correct stance" will be output; otherwise, the information of "incorrect stance" will be output to prompt the person being inspected to rescan.

[0091] Embodiments of the present disclosure also provide a human body security inspection method, which can be based on dual-stance millimeter-wave human body scanning, for example, can be implemented by the above-mentioned human body security inspection system. Figure 5 The flowchart of the millimeter-wave human body security inspection method according to an exemplary embodiment of the present disclosure is illustrated. The method mainly includes the following steps:

[0092] S10: Use a millimeter-wave human body security inspection instrument to scan and inspect the body of the person being inspected in different stances to obtain corresponding millimeter-wave human body images; for example, use a millimeter-wave human body security inspection instrument to scan and inspect the body of the same person being inspected in a first stance and a second stance different from the first stance to obtain the first and second millimeter-wave human body images respectively; and

[0093] S20: Determine whether the person being inspected is carrying prohibited items based at least on the obtained millimeter-wave human body images.

[0094] When it is determined that the person being inspected is suspected of carrying prohibited items, the result can be displayed to the operator, and an alarm can be issued if necessary to guide the person being inspected suspected of carrying prohibited items to accept further inspection; when it is determined that the person being inspected is not carrying prohibited items, the person being inspected can be allowed to pass, and then the security inspection of the next person being inspected can be continued.

[0095] In this method, the first stance and the second stance can be selected such that the part of the body of the person being inspected scanned by the scanning surface when in the first stance and the part of the body of the person being inspected scanned by the scanning surface when in the second stance are at least partially complementary. Furthermore, the combination of the obtained first millimeter-wave human body image and the second millimeter-wave human body image can form a substantially complete contour image of the body of the person being inspected or cover most parts of the body of the person being inspected, including parts with poor imaging quality in conventional inspections, such as the sides, armpits, inner and outer sides of the legs, inner sides of the arms, soles of the feet, etc. of the body of the person being inspected. Exemplarily, when the person being inspected stands at the designated security inspection position in the first stance, the front or back of the body faces the scanning surface of the security inspection instrument, and when standing at the designated security inspection position in the second stance, the side of the body faces the scanning surface. For example, the first stance can be the Figure 2 stance shown, and the second stance can be the Figure 3 stance shown, but the present disclosure is not limited thereto.

[0096] In some embodiments, a guiding device, such as Figure 1 the devices 510 and 520 shown in, may guide or instruct the person to be inspected to stand at the designated security inspection position in a standing posture consistent with or conforming to the designated standing posture, for example, by at least one of voice prompts and visual prompts (see, for example, Figure 5 step S1 in).

[0097] Further, the method may further include determining whether the various different standing postures of the person to be inspected meet the requirements of the corresponding designated standing postures (see, for example, Figure 5 step S2 in). For example, it may be manually determined by an operator based on the standing posture or an image of the standing posture of the person to be inspected, or automatically determined by the system based on an image of the standing posture of the person to be inspected. Exemplarily, it may be determined whether the standing posture of the person to be inspected meets the requirements of the corresponding designated standing posture before scanning the body of the person to be inspected in a standing posture using a millimeter-wave human body security inspection device, so that an expected image can be obtained each time of scanning. For example, before scanning the body of the person to be inspected in a standing posture using a millimeter-wave human body security inspection device, a visible light image of the body of the person to be inspected in this standing posture may be obtained, and based on the visible light image, it may be determined whether the standing posture of the person to be inspected meets the requirements of the designated standing posture. In addition, such a determination may also be made based on the obtained millimeter-wave human body image. For example, when the vast majority of the persons to be inspected can accept security inspection in accordance with the designated standing posture, especially when a suitable standing posture guiding device is provided, this can save time, improve the passing efficiency, and there is no need to additionally provide a separate portrait acquisition device.

[0098] In the illustrated embodiment, when the processor 20 determines that the stance of the person being inspected is incorrect, the corresponding information is transmitted to the security inspection image display device 300 or 400, and the corresponding information can also be transmitted to the guiding devices 510 and / or 520. The image display device 300 or 400 displays a prompt message indicating an incorrect stance, and at the same time, the guiding devices 510 and / or 520 prompt that the stance of the person being inspected is incorrect and prompt to adjust the stance and rescan. If the stance of the person being inspected is correct, the millimeter-wave image is recognized, and the recognition result is temporarily stored, waiting for whether to perform another stance scan. If another stance scan is performed, the above process is repeated, and the recognition result is temporarily stored. After all stance scans are completed, comprehensive processing is performed on the recognition results of all stances. For example, according to the key points determined during stance judgment, the human body is divided into different regions, and according to the coordinates and size of the alarm region, it is calculated which region the alarm box falls into, and the above processing is performed on each alarm box to obtain the region information where it is located; then all alarm boxes are traversed, and duplicate alarm results are merged to obtain a comprehensive output result. Then the final recognition result is output to the devices 300, 400 and / or the guiding devices 510, 520, and a prompt is given according to the recognition result whether the person being inspected is carrying prohibited items. In addition, the human body security inspection system and method according to the present disclosure can also perform only a single stance scan.

[0099] Figure 6 A millimeter-wave human body security inspection method according to a specific example of the present disclosure is illustrated. As shown in the figure, the method includes the following steps:

[0100] S11: Guide the person being inspected to enter the designated security inspection position and assume a first stance that conforms to the first designated stance, and wait for security inspection;

[0101] S12: Scan the person being inspected in the first stance by the millimeter-wave human body security inspection instrument and collect the first millimeter-wave human body image;

[0102] S13: Determine whether the first stance of the person being inspected meets the requirements of the first designated stance; if it is determined that the first stance of the person being inspected does not conform to or is incorrect with respect to the first designated stance, the stance incorrect information is transmitted to the guiding device to prompt the person being inspected to correct the posture (see step S14), and after the person being inspected adjusts the posture, the scan is performed again; repeat step S13 until it is determined that the stance of the person being inspected is correct; if the first stance of the person being inspected conforms to the first designated stance, enter step S15;

[0103] S15: Process the first millimeter-wave human body security inspection image, determine whether the person being inspected is carrying prohibited items, and temporarily store the result; if double stance scanning is performed, enter step S21; otherwise, directly enter step S33, and transmit the existing result as the comprehensive result to the operator;

[0104] S21: Guide the person to be inspected to switch the standing posture to a second standing posture that conforms to the second specified standing posture, and wait for security inspection;

[0105] S22: Scan the person to be inspected in the second standing posture with a millimeter-wave body security scanner and collect a second millimeter-wave body image;

[0106] S23: Determine whether the second standing posture of the person to be inspected meets the requirements of the second specified standing posture; if it is determined that the second standing posture of the person to be inspected does not conform to or is incorrect with respect to the second specified standing posture, then transmit the information indicating incorrect standing posture to the guiding device to prompt the person to be inspected to correct the posture (see step S24), and re-perform the scan after the person to be inspected has adjusted the posture; repeat step S23 until it is determined that the standing posture of the person to be inspected is correct; if the second standing posture of the person to be inspected conforms to the second specified standing posture, then proceed to step S25;

[0107] S25: Process the second millimeter-wave body security inspection image, determine whether the person to be inspected is carrying contraband, temporarily store the result, and proceed to step S31;

[0108] S31: Perform comprehensive processing on the judgment results of different standing postures, partition the body image according to key points, determine the area of the alarm position, and perform duplicate removal processing on information such as the alarm position to obtain a comprehensive result; if the comprehensive result shows that the person to be inspected is not carrying contraband, then proceed to step S32 to display the judgment result and permit the person to be inspected to pass; if the comprehensive result shows that the person to be inspected is carrying contraband, then proceed to step S33, for example, frame the position of the contraband in a specific color on the millimeter-wave image of the person to be inspected and the mannequin diagram of the display device, and transmit the result to the guiding device, and the display device displays the inspection result to prompt the person to be inspected that they are carrying contraband and give an alarm. In Figure 5 and 6 In the illustrated embodiment, the optional steps are outlined by dashed boxes.

[0109] Although the embodiments of the present disclosure have been shown and described, it will be understood by those of ordinary skill in the art that various changes can be made therein without departing from the principle and spirit of the present disclosure, and the scope of the present disclosure is defined by the appended claims and their equivalents.

Claims

1. A millimeter-wave human body security inspection method based on double postures, comprising: judging whether the first posture of the person to be inspected standing at the designated security inspection position conforms to the requirements of the first designated posture; after judging that the first posture conforms to the first designated posture, using a millimeter-wave human body security inspection device to scan and inspect the body of the person to be inspected in the first posture to obtain a first millimeter-wave human body image; after the person to be inspected standing at the designated security inspection position switches from the first posture to a second posture different from the first posture, judging whether the second posture conforms to the requirements of the second designated posture; after judging that the second posture conforms to the second designated posture, using the millimeter-wave human body security inspection device to scan and inspect the body of the same person to be inspected standing at the designated security inspection position in the second posture to obtain a second millimeter-wave human body image; and determining whether the person to be inspected is carrying prohibited items based at least on both the first millimeter-wave human body image and the second millimeter-wave human body image.

2. The millimeter-wave human body security inspection method according to claim 1, wherein the millimeter-wave human body security inspection device has a scanning surface for scanning the body of the person to be inspected, and the method further comprises: guiding the first posture and the second posture of the person to be inspected, so that the part of the body of the person to be inspected scanned by the scanning surface when in the first posture and the part of the body of the person to be inspected scanned by the scanning surface when in the second posture are at least partially complementary, and the combination of the obtained first millimeter-wave human body image and the second millimeter-wave human body image forms a substantially complete contour image of the body of the person to be inspected.

3. The millimeter-wave human body security inspection method according to claim 2, wherein the first posture and the second posture are selected such that the combination of the first millimeter-wave human body image and the second millimeter-wave human body image at least includes images of the front and side of the body of the person to be inspected, the armpits, the inner and outer thighs, and the inner arms.

4. The millimeter-wave human body security inspection method according to claim 1, wherein the millimeter-wave human body security inspection device has a scanning surface for scanning the body of the person to be inspected, and the method further comprises: guiding or instructing the person to be inspected to stand at the designated security inspection position in the first posture, so that the front or back of the body of the person to be inspected faces the scanning surface; and / or guiding or instructing the person to be inspected to stand at the designated security inspection position in the second posture, so that the side of the body of the person to be inspected faces the scanning surface.

5. The millimeter-wave human body security inspection method according to claim 4, guiding or instructing the person to be inspected to stand at the designated security inspection position in the first posture or the second posture by at least one of voice prompt and visual prompt through a guiding device.

6. The millimeter-wave human body security inspection method according to claim 1, wherein "judging whether the first posture of the person to be inspected conforms to the requirements of the first designated posture" includes: obtaining a first visible light image of the body of the person to be inspected in the first posture, and judging whether the first posture of the person to be inspected conforms to the requirements of the first designated posture based on the first visible light image; and / or "judging whether the second posture conforms to the requirements of the second designated posture" includes: Obtain a second visible light image of the body of the person to be inspected in the second standing posture, and determine whether the second standing posture of the person to be inspected meets the requirements of the second specified standing posture based on the second visible light image.

7. The millimeter-wave human body security inspection method according to claim 1, wherein Based on the first millimeter-wave human body image, determine whether the first standing posture of the person to be inspected meets the requirements of the first specified standing posture; and / or Based on the second millimeter-wave human body image, determine whether the second standing posture of the person to be inspected meets the requirements of the second specified standing posture.

8. A millimeter-wave human body security inspection system based on a double standing posture, comprising: A millimeter-wave human body security inspection device, which is configured to: Scan and inspect the body of the person to be inspected standing at the specified security inspection position in the first standing posture to obtain a first millimeter-wave human body image, and In a state where the person to be inspected standing at the specified security inspection position switches from the first standing posture to a second standing posture different from the first standing posture, scan and inspect the body of the same person to be inspected standing at the specified security inspection position in the second standing posture to obtain a second millimeter-wave human body image; And A processor, which communicates with the millimeter-wave human body security inspection device and is configured to determine whether the person to be inspected is carrying prohibited items based on at least both the first millimeter-wave human body image and the second millimeter-wave human body image, The processor is further configured to: Before the millimeter-wave human body security inspection device scans and inspects the body of the person to be inspected in the first standing posture, determine whether the first standing posture of the person to be inspected meets the requirements of the first specified standing posture; Before the millimeter-wave human body security inspection device scans and inspects the body of the person to be inspected in the second standing posture, determine whether the second standing posture of the person to be inspected meets the requirements of the second specified standing posture.

9. The millimeter-wave human body security inspection system according to claim 8, wherein the millimeter-wave human body security inspection device has a scanning surface for scanning the body of the person to be inspected, and The millimeter-wave human body security inspection system is configured to guide the first standing posture and the second standing posture of the person to be inspected, so that the part of the body of the person to be inspected scanned by the scanning surface when in the first standing posture and the part of the body of the person to be inspected scanned by the scanning surface when in the second standing posture are at least partially complementary, whereby the combination of the first millimeter-wave human body image and the second millimeter-wave human body image obtained by scanning with the millimeter-wave human body security inspection device forms a substantially complete contour image of the body of the person to be inspected.

10. The millimeter-wave human body security inspection system according to claim 9, wherein the millimeter-wave human body security inspection system is configured to select the first standing posture and the second standing posture such that the combination of the first millimeter-wave human body image and the second millimeter-wave human body image obtained by scanning with the millimeter-wave human body security inspection device at least includes images of the front and side of the body of the person to be inspected, the armpits, the inner and outer thighs, and the inner arms.

11. The millimeter-wave human body security inspection system according to claim 8, wherein the millimeter-wave human body security inspection device has a scanning surface for scanning the body of the person to be inspected, and the millimeter-wave human body security inspection system further comprises: A guiding device, which is configured to: Guide or instruct the person to be inspected to stand at the designated security inspection position in the first standing posture, so that the front or back of the person's body faces the scanning surface; and / or Guide or instruct the person to be inspected to stand at the designated security inspection position in the second standing posture, so that the side of the person's body faces the scanning surface.

12. The millimeter-wave human body security inspection system according to claim 11, wherein the guiding device is configured to guide or instruct the person to be inspected to stand at the designated security inspection position in the first standing posture or the second standing posture by at least one of voice prompt and visual prompt.

13. The millimeter-wave human body security inspection system according to claim 11, wherein the guiding device includes: A voice prompt device configured to prompt the person to be inspected to stand at the designated security inspection position in the first standing posture or the second standing posture by voice; and / or A display device which is arranged near the millimeter-wave human body security inspection instrument and is visible to the person to be inspected, and the display device is configured to prompt the person to be inspected to stand at the designated security inspection position in the first standing posture or the second standing posture visually.

14. The millimeter-wave human body security inspection system according to claim 8, further comprising: A photographing device configured to acquire a first visible light image of the body of the person to be inspected in the first standing posture and a second visible light image of the body of the person to be inspected in the second standing posture; Wherein, the processor is further configured to: Judge whether the first standing posture of the person to be inspected meets the requirements of the first designated standing posture based on the first visible light image; and / or Judge whether the second standing posture of the person to be inspected meets the requirements of the second designated standing posture based on the second visible light image.

15. The millimeter-wave human body security inspection system according to claim 8, wherein the processor is further configured to: Judge whether the first standing posture of the person to be inspected meets the requirements of the first designated standing posture based on the first millimeter-wave human body image; and / or Judge whether the second standing posture of the person to be inspected meets the requirements of the second designated standing posture based on the second millimeter-wave human body image.

Images