CN110969747A - Anti-following access control system and anti-following method - Google Patents
Anti-following access control system and anti-following method Download PDFInfo
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- 238000000034 method Methods 0.000 title claims abstract description 18
- 238000003331 infrared imaging Methods 0.000 claims abstract description 28
- 238000004891 communication Methods 0.000 claims abstract description 5
- 238000012545 processing Methods 0.000 claims description 11
- 239000000284 extract Substances 0.000 claims description 5
- 210000001930 leg bone Anatomy 0.000 claims 5
- 230000001360 synchronised effect Effects 0.000 claims 2
- 230000006399 behavior Effects 0.000 abstract description 9
- 230000002265 prevention Effects 0.000 abstract description 3
- 239000011159 matrix material Substances 0.000 description 8
- 238000005516 engineering process Methods 0.000 description 4
- 238000001931 thermography Methods 0.000 description 4
- 210000000988 bone and bone Anatomy 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
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- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B13/00—Burglar, theft or intruder alarms
- G08B13/18—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength
- G08B13/189—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using passive radiation detection systems
- G08B13/19—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using passive radiation detection systems using infrared-radiation detection systems
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N5/00—Details of television systems
- H04N5/30—Transforming light or analogous information into electric information
- H04N5/33—Transforming infrared radiation
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Abstract
The invention provides a tailgating prevention access control system and a tailgating prevention method, wherein the system comprises a first infrared sensor arranged at the top of an access channel, a second infrared sensor and a third infrared sensor respectively arranged at two sides of the access channel, and a control device which is in communication connection with the first infrared sensor, the second infrared sensor and the third infrared sensor respectively, the control device is used for judging whether a heat source body entering the access channel is a human body walking side by side or a human body walking front and back synchronously according to infrared imaging provided by the first infrared sensor, and the control device is further used for analyzing the number of the human bodies in the access channel according to the infrared imaging provided by the second infrared sensor and the third infrared sensor, so that whether tailgating behaviors exist is judged. The anti-following access control system can accurately identify following behaviors.
Description
Technical Field
The invention relates to the field of security entrance guard, in particular to an anti-following entrance guard system and an anti-following method.
Background
The anti-following technology is a security technology for ensuring single person access in an access control system, and is an effective method for allowing only specified authorized personnel to enter and rejecting unauthorized personnel outside a door, wherein the anti-following technology is suitable for high-security-level entrance.
Video anti-following is a commonly used anti-following technique. The video anti-tailing is to place a camera in the channel and judge whether more than two people exist in the channel through video identification. However, processing video signals requires a processor with good performance to meet the requirement of real-time processing, and in addition, a camera with satisfactory definition is required, so that the cost of the video anti-tracking technology is high.
Disclosure of Invention
The invention aims to provide a low-cost and accurate-identification anti-following access control system and an anti-following method.
The embodiment of the invention provides an anti-following access control system which comprises a first infrared sensor arranged at the top of an entrance channel, a second infrared sensor and a third sensor which are respectively arranged at two sides of the entrance channel, and a control device which is respectively in communication connection with the first infrared sensor, the second infrared sensor and the third infrared sensor, wherein the control device is used for judging whether a heat source body entering the entrance channel is a human body walking side by side or a human body walking front and back synchronously according to infrared imaging provided by the first infrared sensor, and the control device is further used for analyzing the number of the human bodies in the entrance channel according to infrared imaging provided by the second infrared sensor and the third infrared sensor so as to judge whether a following behavior exists.
In the embodiment of the invention, the anti-following access control system further comprises an alarm connected with the control device, and when the control device judges that the number of the human bodies entering the channel exceeds one, the alarm is controlled to give out an alarm sound.
In the embodiment of the invention, the control device respectively extracts the skeleton images of the legs of the human body from the infrared images provided by the second infrared sensor and the third infrared sensor, so that the number of the human bodies is judged according to the number of the skeletons of the legs of the human bodies.
In the embodiment of the present invention, the control device extracts a human leg skeleton image from the infrared imaging, and determines the number of human bodies according to the number of human leg skeletons, and specifically includes:
subtracting the background image from the extracted infrared imaging to obtain a temperature image of the heat source body;
carrying out binarization on the obtained temperature image of the heat source body and carrying out Gaussian blur processing;
extracting a skeleton image from the image subjected to Gaussian blur processing;
in the skeleton image, the number of human legs is identified.
In the embodiment of the invention, the control device judges whether the heat source body is a human body walking side by side or a human body walking front and back synchronously according to whether the length-width ratio of the heat source body in the channel accords with the set range.
The embodiment of the invention also provides an anti-trailing method of the access control system, which comprises the following steps:
judging whether a heat source body entering the passage is a human body walking side by side or a human body walking front and back synchronously according to infrared imaging provided by a first infrared sensor arranged at the top of the door entering passage;
analyzing the number of human bodies in the channel according to infrared imaging provided by a second infrared sensor and a third infrared sensor which are arranged on two sides of the door access channel respectively;
and judging whether the following behavior exists according to whether the heat source body entering the channel is a human body walking side by side or a human body walking synchronously front and back and the number of the human bodies in the channel.
Compared with the prior art, the anti-following access control system and the anti-following method provided by the invention judge whether the heat source body entering the access channel is a human body walking side by side or a human body walking synchronously back and forth according to the infrared imaging provided by the first infrared sensor arranged at the top of the access channel; analyzing the number of human bodies in the channel according to infrared imaging provided by a second infrared sensor and a third infrared sensor which are arranged on two sides of the door access channel respectively; judging whether trailing behaviors exist or not according to whether the heat source bodies entering the channel are human bodies walking side by side or human bodies walking front and back synchronously or the number of the human bodies in the channel, and accurately judging the number of the human bodies; in addition, because the infrared imaging is adopted for image processing, the information content of the infrared imaging is small, the data amount required to be processed by the control device is small, the control device can be realized by adopting a low-end processor, and the cost of the system is reduced.
Drawings
Fig. 1 is a schematic structural diagram of an anti-following access control system according to an embodiment of the present invention.
Fig. 2 is a schematic control flow diagram of the anti-following access control system according to the embodiment of the present invention.
Fig. 3 is a schematic flow chart of detecting the number of human legs of the anti-following access control system according to the embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The following detailed description of implementations of the invention refers to specific embodiments,
as shown in fig. 1, in the embodiment of the present invention, a tailgating prevention access control system is provided, including a first infrared sensor 11 disposed at the top of an access passage, a second infrared sensor 12 and a third infrared sensor 13 disposed at two sides of the access passage, a control device 14 in communication connection with the first infrared sensor 11, the second infrared sensor 12 and the third infrared sensor 13, and an alarm 15 in communication connection with the control device 14. It should be noted that the door entrance passage may include an external passage gate and an internal passage gate which are disposed at both ends of the passage, and after the external passage gate is opened, the external passage gate is opened to detect the number of human bodies entering the passage.
The first infrared sensor 11 is used for monitoring the activity of the heat source body in the door access from a top view, and the second infrared sensor 12 and the third infrared sensor 13 are used for monitoring the activity of the heat source body in the door access from a side view. The first infrared sensor 11, the second infrared sensor 12 and the third infrared sensor 13 send the monitored infrared images to the control device 14 in real time. The control device 14 is configured to analyze the infrared images provided by the first infrared sensor 11, the second infrared sensor 12, and the third infrared sensor 13, so as to determine whether there is a trailing behavior. The control device 14 is a computer device with graphic computing capability, and can be implemented by a computer.
As shown in fig. 2, the anti-tailing access control system works as follows:
when the gate positioned in the external channel is opened, the control device 14 judges whether the heat source bodies entering the channel are human bodies walking side by side or human bodies walking back and forth according to the infrared imaging provided by the first infrared sensor 11, and when the heat source bodies entering the channel are human bodies walking side by side, the number of the human bodies in the channel exceeds 1, and the alarm 15 is controlled to give an alarm sound; otherwise, judging that no one trails, and opening the internal gate. Meanwhile, the control device 14 also analyzes the number of human bodies in the channel according to the infrared imaging provided by the second infrared sensor 12 and the third infrared sensor 13, so as to judge whether the following behavior exists. When the control device 14 judges that the trailing behavior exists, the alarm 15 is controlled to give an alarm sound.
Specifically, the control device 14 first detects whether a heat source body exists in the channel and whether the heat source body completely enters the channel; and when the heat source body completely enters the channel, judging whether the heat source body is a human body walking side by side or a human body walking front and back synchronously according to whether the length-width ratio of the heat source body in the channel accords with a set range. It should be noted that, when a human body passes through the channel, the human body is walking in a direction opposite to the door, so in the infrared image taken by the first infrared sensor 11 from the top view, the image of the human body is a rectangular-like image, the long side of the image is far larger than the wide side, the long side is the width of the human body, and the wide side is the thickness of the human body. If two people walk side by side, the long edge in thermal imaging is the sum of the widths of the two people, and the length-width ratio is larger than that of one person. Therefore, whether the heat source body is a human body walking side by side or a human body walking front and back synchronously can be judged through the preset length-width ratio range, and the identification accuracy is improved.
Since the second infrared sensor 12 and the third infrared sensor 13 are disposed on both sides of the tunnel, the posture of the person walking is photographed from a side angle in the infrared thermal imaging provided by the second infrared sensor 12 and the third infrared sensor 13. In the walking process of the person, the two legs of the person are in a tandem state, so that the number of the human bodies in the channel can be judged according to the number of the legs of the person in the infrared thermal imaging provided by the second infrared sensor 12 and the third infrared sensor 13. In addition, since the second infrared sensor 12 and the third infrared sensor 13 are disposed at both sides of the passage, if an object such as a box carried by a person blocks the leg at one side, the leg of the person can be photographed by the infrared sensor at the other side. Therefore, the control device 14 can determine that the number of human bodies in the entire passage exceeds 1 as long as it is determined that the number of human bodies exceeds 1 in the infrared thermal imaging of the one-side infrared sensor.
As shown in fig. 3, the control device 14 extracts an image of bones of a leg of a human body from the infrared imaging, so as to determine the number of the human body according to the number of the bones of the leg of the human body, and the specific process includes:
subtracting the background image from the currently extracted infrared imaging to obtain a temperature image of the heat source body, wherein a temperature image matrix D of the heat source body is S-B, B is a background temperature matrix extracted in advance under the unmanned condition, and S is a current temperature difference matrix;
binarizing the obtained temperature image of the heat source body, setting a temperature threshold (for example, setting the temperature threshold to 10), and obtaining a binarized temperature image matrix
Performing Gaussian blur processing on the image matrix of the binarization temperature and extracting a skeleton image matrix:
wherein, xmax (y) and xmin (y) are respectively the maximum value and the minimum value of x when the abscissa is y and O (x, y) is equal to 1 in the binary temperature image matrix O (x, y);
in the skeleton image, the number of human legs is identified l (y) max, wherein l (y) is the maximum value of l (y) in the skeleton image matrix G, the abscissa is y, G (x, y) is equal to the number of 1, and l (y) max is.
In summary, the anti-following access control system and the anti-following method of the present invention determine whether the heat source entering the access channel is a human body walking side by side or a human body walking synchronously back and forth according to the infrared imaging provided by the first infrared sensor disposed at the top of the access channel; analyzing the number of human bodies in the channel according to infrared imaging provided by a second infrared sensor and a third infrared sensor which are arranged at two sides of the door access channel respectively; judging whether trailing behaviors exist or not according to whether the heat source bodies entering the channel are human bodies walking side by side or human bodies walking front and back synchronously or the number of the human bodies in the channel, and accurately judging the number of the human bodies; in addition, because the infrared imaging is adopted for image processing, the information content of the infrared imaging is small, the data amount required to be processed by the control device is small, the control device can be realized by adopting a low-end processor, and the cost of the system is reduced.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (10)
1. The utility model provides a prevent following access control system which characterized in that, including set up in the first infrared sensor at passageway top of entering, set up respectively in the second infrared sensor of passageway both sides of entering, third sensor and respectively with first infrared sensor, second infrared sensor reach the controlling means that third infrared sensor keeps communication connection, controlling means is used for the basis infrared imaging that first infrared sensor provided judges whether the heat source body in the entering passageway is the human body of walking side by side or the human body of synchronous walking in front and back, controlling means further basis the human body quantity in the infrared imaging analysis passageway that second infrared sensor with third infrared sensor provided to judge whether there is the following action.
2. The anti-tailing access control system according to claim 1, further comprising an alarm connected to the control device, wherein the alarm is controlled to sound an alarm when the control device determines that the number of human bodies entering the passageway exceeds one.
3. The anti-tailing access control system of claim 1, wherein the control means extracts human leg bone images from the infrared images provided by the second infrared sensor and the third infrared sensor, respectively, to judge the number of human bodies from the number of human leg bones.
4. The anti-tailing access control system of claim 3, wherein the control device extracts human leg skeleton images from infrared imaging, and judges the number of human bodies according to the number of human leg skeletons, and specifically comprises:
subtracting the background image from the extracted infrared imaging to obtain a temperature image of the heat source body;
carrying out binarization on the obtained temperature image of the heat source body and carrying out Gaussian blur processing;
extracting a skeleton image from the image subjected to Gaussian blur processing;
in the skeleton image, the number of human legs is identified.
5. The anti-tailing access control system according to claim 1, wherein the control device determines whether the heat source body is a side-by-side walking body or a front-back synchronous walking body according to whether the length-width ratio of the heat source body in the channel meets a set range.
6. An anti-trail method for an access control system, comprising:
judging whether a heat source body entering the passage is a human body walking side by side or a human body walking front and back synchronously according to infrared imaging provided by a first infrared sensor arranged at the top of the door entering passage;
analyzing the number of human bodies in the channel according to infrared imaging provided by a second infrared sensor and a third infrared sensor which are arranged on two sides of the door access channel respectively;
and judging whether the following behavior exists according to whether the heat source body entering the channel is a human body walking side by side or a human body walking synchronously front and back and the number of the human bodies in the channel.
7. The anti-tailing method of an entrance guard system according to claim 6, characterized in that an alarm is issued when it is judged that the number of human bodies entering the passageway exceeds one.
8. The anti-tailing method of an entrance guard system of claim 6, wherein the number of human bodies is determined according to the number of human body legs by extracting human body leg bone images from the infrared images provided by the second infrared sensor and the third infrared sensor, respectively.
9. The anti-tailing method of an access control system of claim 8, wherein the human leg bone image is extracted from the infrared imaging, so that the number of human bodies is judged according to the number of the human leg bones, and the method specifically comprises the following steps:
subtracting the background image from the extracted infrared imaging to obtain a temperature image of the heat source body;
carrying out binarization on the obtained temperature image of the heat source body and carrying out Gaussian blur processing;
extracting a skeleton image from the image subjected to Gaussian blur processing;
in the skeleton image, the number of human legs is identified.
10. The anti-tailing method of the access control system according to claim 6, wherein whether the heat source body is a human body walking side by side or a human body walking front and back synchronously is judged according to whether the length-width ratio of the heat source body in the channel meets a set range.
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Application publication date: 20200407 |