JP2012093912A - Entering body detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an entering body detection device capable of specifying the position of a detection area where an entering body is detected from heat change with high precision in an image obtained by photographing a monitor region.SOLUTION: An entering body detection device 1 includes a sensor part 20 which defines a detection area nearby a restriction object restricting a movement of a person and outputs a detection level corresponding to heat rays emitted from the detection area; an imaging part 10 which acquires a monitor image obtained by photographing the monitor region including the restriction object and detection area in predetermined cycles; change area extraction means 72 of extracting a region corresponding to a person; person image position extraction means 73 of extracting the position of the region, extracted from the monitor image when the detection level reaches a predetermined level, as a person image position; and area specification means 74 of extracting an end of a movement range of the person restricted by the restriction object from the monitor image based upon a plurality of person image positions extracted in a predetermined period, and specifying a region indicative of the detection area in the monitor image such that the end of the movement range is one end of the detection area.

Description

  The present invention relates to an intruding object detection apparatus that detects an intruding object based on a thermal change in a detection area and images a monitoring area including the detecting area.

  In recent years, an intruding object detection device that detects an intruding object using a sensor such as a pyroelectric infrared sensor (PIR sensor: Passive InfraRed Sensor) has been widely developed. For example, in Patent Document 1, in such an intruding object detection device, the detection is performed so that the operator can confirm what position (range) the detection area in which the sensor detects the intruding object is set. A technique is disclosed in which a marker indicating a detection area is superimposed and displayed on a monitoring image obtained by photographing a region including an area with a camera. However, in the technique described in Patent Document 1, it is necessary to set the viewing angle of the camera and the sensor to be a predetermined angle in advance, and the camera orientation and the sensor orientation cannot be arbitrarily changed. .

  On the other hand, Patent Document 2 discloses a technique for superimposing and displaying a marker indicating a detection area of a sensor on a monitoring image regardless of the relative relationship between the viewing angle of the camera and the sensor. The monitoring image processing device disclosed in Patent Document 2 extracts the position of a moving object (operator) on a monitoring image taken when a walk test is performed by an operator by image processing of motion detection, A set of moving object positions on the monitoring image when the sensor detects an object is defined as a detection area.

JP 7-23373 A JP 2006-178515 A

Generally, a detection area composed of one or more detection zones is set in the PIR sensor, and the PIR sensor detects a change in thermal energy in each detection zone using a pyroelectric element. Due to such characteristics, the PIR sensor requires a certain amount of time accompanying the movement of the human body in order to detect a change in thermal energy, and therefore the position of the human body when the PIR sensor detects a change in thermal energy, There may be a difference between the detection area (detection zone) where the human body actually exists.
Therefore, in the technique described in Patent Document 2, the position (range) of the detection area of the PIR sensor on the monitoring image may not be correctly specified.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an intruding object detection device that can accurately identify an area representing a detection area of a sensor that detects an intruding object based on a thermal change on an image obtained by capturing a monitoring area. .

  The present invention for solving such a problem includes a sensor unit that outputs a detection level corresponding to a heat ray radiated from a detection area, a limit object and a detection area, in the vicinity of a restricted object that restricts movement of a person. An intruding object detection device that identifies an area corresponding to a detection area on a monitoring image by a test walk by a person. Such an intruding object detection device includes a region extraction unit that extracts a region corresponding to a person in a monitoring image, and an imaging unit when a detection level output by the sensor unit is a value indicating that a person is present in the detection area. The position of the region extracted from the monitoring image acquired by the human image position extracting means for extracting the position of the human image as a human image position, and a restriction by a restriction based on a plurality of human image positions extracted by the human image position extracting means during a predetermined period And an area specifying means for detecting an end of the movement range of the person to be detected on the monitoring image and specifying an area representing the detection area on the monitoring image with the end of the movement range as one end of the detection area.

  Further, in the intruding object detection device according to the present invention, the area specifying unit obtains the appearance frequency of the human image position extracted during a predetermined period for each position on the monitoring image, and the appearance frequency is relative to the adjacent position. It is preferable that the sharply decreasing position is the end of the movement range.

  Alternatively, in the intruding object detection device according to the present invention, the human image position extraction means stores the human image position and the detection level in association with each other when the detection level becomes a value indicating that a person is present in the detection area, It is preferable that the specifying unit sets the position where the detection level stored in association with the human image position on the monitoring image rapidly decreases with respect to the adjacent position as the end of the movement range.

  Furthermore, the intruding object detection device according to the present invention further includes a display unit, and when the area specifying unit cannot specify the end on the monitoring image, the detection area set in the sensor unit is not correct. Is preferably displayed on the display unit.

  The intruding object detection device according to the present invention has an effect that a region representing a detection area of a sensor that detects an intruding object on the image obtained by capturing a monitoring region can be identified with high accuracy.

It is a schematic block diagram which shows the whole system structure of the security system to which this invention is applied. (A) is the figure which looked at the imaging range of the imaging part, and the detection area of the sensor part from the diagonal direction, (b) is the figure which looked at the imaging range of the imaging part, and the detection area of the sensor part from the perpendicular direction. (C) is a figure showing the monitoring image of an imaging part, and the detection area of a sensor part. It is an example of appearance frequency distribution of a human image position. It is a flowchart which shows the process at the time of the registration mode by an area setting means. It is a flowchart which shows the process at the time of the alert mode by an abnormality monitoring means. It is an example of peak distribution of a detection level. It is a flowchart which shows the process at the time of the registration mode by an area setting means.

Hereinafter, an intruding object detection apparatus according to an embodiment of the present invention will be described with reference to the drawings.
The intruding object detection device detects an intruding object based on a thermal change in the detection area, and acquires a monitoring image obtained by photographing a monitoring area including the detection area. The detection area is an area adjacent to an object (such as a structure such as a building wall) that restricts the movement of a person, and the monitoring image includes a part or all of the restricted object. In particular, in this intruding object detection device, a walk test (test walking) is performed in which the worker walks in the monitoring area to confirm the position of the detection area on the monitoring image. At this time, the intruding object detection device extracts the position of the human body from the monitoring image acquired when it is determined that the human body exists due to the thermal change in the detection area. Then, the intruding object detection device specifies the boundary of the detection area on the monitoring image based on the distribution of the appearance frequency of the position of the human body. Thereby, the intruding object detection device can statistically determine the range of the detection area on the monitoring image, and can specify the region representing the detection area with high accuracy. When an intruding object is actually detected, by displaying the detection area as a marker on the monitoring image at this time, it is possible to easily grasp the cause of the alarm and the surrounding situation.

  FIG. 1 is a diagram showing an overall system configuration of a security system to which the present invention is applied. As shown in FIG. 1, the security system 100 includes intruding object detection devices 1 and 2, a security device 3, an operation indicator 4, and a monitoring center device 5. The intruding object detection devices 1 and 2, the security device 3, and the operation indicator 4 are installed in or near the monitoring area and are connected by a wireless or wired local area network 6. On the other hand, the monitoring center device 5 is installed in a remote security center and is connected to the security device 3 via a wide area communication network 7 such as a public telephone line.

  When the intruding object detection devices 1 and 2 detect an intruding object that has entered the detection area, the intruding object detection signal indicating that the intruding object has been detected and a monitoring image obtained by capturing the monitoring area at that time are displayed on the local area network 6. To the security device 3. When the security device 3 receives the intruding object detection signal and the monitoring image from the intruding object detection device 1 or 2, the security device 3 monitors information such as the intruding object detection signal, the monitoring image, and an identification code that identifies the monitoring area where the intruding object is detected. Transmit to the center device 5. Note that the identification code for specifying the monitoring area where the intruding object is detected can be, for example, the identification code of the intruding object detecting devices 1 and 2, the security device 3, or the corresponding monitoring area.

  Further, the intruding object detection devices 1 and 2 may periodically transmit the monitoring image to the operation display 4. The operation indicator 4 has, for example, a touch panel display, and displays operation buttons for the user to input operation commands. When the user presses one of the displayed operation buttons, the operation display 4 displays a monitoring image received from the intruding object detection device 1 or 2 according to an operation command corresponding to the operation button. Note that the operation indicator 4 is not a touch panel display, and may have a display device for displaying information and an input device for a user to perform an input operation such as a keypad or a trackball. Good.

The monitoring area may be outdoors or indoors, but in the present embodiment, a case where a garden of a house is monitored as the monitoring area will be described as an example.
Further, the intruding object detection devices 1 and 2 and the operation indicator 4 may be configured to be connected to the security device 3 through signal lines and to perform communication between the devices via the security device 3.
Further, when the security device 3 receives the intruding object detection signal from the intruding object detection device 1 or 2, the security device 3 determines whether or not there is an intrusion abnormality and then transmits information such as the intruding object detection signal, the monitoring image, and the identification code to the monitoring center device. You may make it transmit to 5. In this case, for example, a reader for detecting an IC tag carried by a user of the security system is provided in the security device 3 separately. The security device 3 determines that there is an intrusion abnormality only when the intruding object detection signal and the monitoring image are received from the intruding object detection device 1 or 2 when the reader does not detect the IC tag in the monitoring area.

  Hereinafter, the configuration and operation of the intruding object detection devices 1 and 2 will be described. Since the configuration and operation of the intruding object detection devices 1 and 2 are the same, the intruding object detection device 1 will be described below as a representative.

  The intruding object detection device 1 is installed on, for example, a wall surface on the outdoor side of a house and monitors a space near a wall including a window or a door. That is, the intruding object detection device 1 detects an invasion action into the indoor portion of the house to be protected in advance on the outdoor side, and accordingly, along the wall (restricted object) that forms a boundary with the indoor portion. Monitor wall space. The intruding object detection device 1 operates in one of two operation modes: a registration mode for setting a monitoring area and the like, and a warning mode for monitoring an intruder who attempts to enter through a window or door. For this purpose, the intruding object detection apparatus 1 includes an imaging unit 10, a sensor unit 20, a storage unit 30, an operation unit 40, a display unit 50, a communication unit 60, and a monitoring processing unit 70.

The imaging unit 10 acquires a monitoring image obtained by capturing a monitoring area including a detection area where the sensor unit 20 detects an intruding object. For this purpose, the imaging unit 10 includes a two-dimensional detector composed of a photoelectric converter such as a CCD or C-MOS sensor, an imaging optical system that forms an image of a monitoring region on the two-dimensional detector, The electric signal output from the two-dimensional detector is amplified and configured by an electric circuit for analog / digital (A / D) conversion. Further, the imaging unit 10 may be an NTSC type camera or a high resolution type digital camera for high definition. The angle of view of the lens of the imaging unit 10 of the present embodiment is 90 ° to 180 °, and the imaging unit 10 is installed so as to be able to photograph a wall surface provided with a window or a door and a space near a wall that is a detection area. The imaging unit 10 captures images at regular time intervals (for example, 1/5 second) to acquire a monitoring image, and transmits the monitoring image to the monitoring processing unit 70.
The monitoring image has, for example, horizontal 340 pixels × vertical 240 pixels, and each pixel is expressed as digital image data having pixel values of 0 to 255. Note that the imaging unit 10 may create the monitoring image as a color image.

The sensor unit 20 includes a pyroelectric infrared sensor (PIR sensor; Passive InfraRed Sensor) using a pyroelectric element and an optical system. A detection area where the PIR sensor detects an intruding object is configured by one or a plurality of detection zones. Each detection zone is composed of a pair of zones, and each detection zone is defined in a region where an intruding object is to be detected.
The PIR sensor includes, for example, a pair of pyroelectric elements connected with opposite polarities. And a PIR sensor condenses the infrared rays (heat ray) from one zone among a pair of zones of each detection zone, receives it with one pyroelectric element, and converts it into a positive voltage. In addition, the PIR sensor collects infrared rays (heat rays) from the other zone of each detection zone by an optical system, receives it by the other pyroelectric element, and converts it into a negative voltage. Therefore, when the human body passes in a direction crossing the pair of zones, a voltage change from a positive voltage to a negative voltage (or from a negative voltage to a positive voltage) occurs in the PIR sensor.
Therefore, the sensor unit 20 obtains a detection level P representing the degree of certainty that a person exists in the detection area based on the magnitude of the voltage change. The detection level P increases as the voltage change increases. For example, the magnitude of the voltage change itself may be used as the detection level P. Then, the sensor unit 20 transmits detection level information indicating the detection level P to the monitoring processing unit 70.

  When it is intended to detect an intruder trying to enter through a window or door of a house, a space near the wall of the house is set as a detection area. In that case, the viewing angle of the sensor unit 20 may be relatively narrow, for example, about 20 °. Therefore, the viewing angle of the sensor unit 20 is narrower than the angle of view of the imaging unit 10, and the detection area is a partial region included in the monitoring image.

  FIG. 2A is a diagram in which the imaging range of the imaging unit 10 and the detection area of the sensor unit 20 are viewed from an oblique direction. In FIG. 2A, an angle of view 201 is an angle of view of the imaging unit 10 and is set so that the imaging unit 10 captures the imaging range 200. The viewing angle 211 is a viewing angle of the sensor unit 20 and is set so that the sensor unit 20 detects an intruding object in the area of the detection area 210. As shown in FIG. 2A, the imaging range 200 of the imaging unit 10 is detected by the sensor unit 20 so that the monitoring factor can easily grasp the alarming factor and the surrounding situation when performing an abnormality check with an image. A wide range is set to include the area 210.

  FIG. 2B is a diagram of the imaging range of the imaging unit 10 and the detection area of the sensor unit 20 as seen from the vertical direction. In FIG. 2B, an angle of view 212 is an angle of view of the imaging unit 10 and is set so that the imaging unit 10 captures the imaging range 202. The viewing angle 213 is the viewing angle of the sensor unit 20 and is set so that the sensor unit 20 detects an intruding object in the area of the detection area 203. As shown in FIG. 2B, the intruding object detection device 1 is installed on the wall 220 (vertical line portion) of the house so that an intruding object entering the house can be detected and photographed. The shooting range 202 and the detection area 203 of the sensor unit 20 are set so as to include the edge of the wall 220, respectively, and the shooting range 202 of the shooting unit 10 is set to include the wall surface of the wall 220.

  FIG. 2C is a diagram illustrating a monitoring image of the imaging unit 10 and a detection area of the sensor unit 20. In FIG. 2C, an image 204 is a monitoring image captured by the imaging unit 10, and a region 214 (hatched portion) in the monitoring image 204 represents a detection area of the sensor unit 20, and a region 221 (vertical line portion). ) Represents an area where the wall 220 of the house was imaged. As shown in FIG. 2C, the imaging unit 10 images a space along the house wall 220, and the sensor unit 20 uses the space along the house wall 220 as a detection area 214. The monitoring image 204 is set so as to include the detection area 214.

  Thus, in the intruding object detection device 1 of the present embodiment, the imaging range of the imaging unit 10 is set so as to include the detection area of the sensor unit 20, so when the detection area is set near the wall of the house, The wall surface of the monitoring image is imaged on either the left or right end side. A region having a predetermined size determined by the viewing angle of the sensor unit 20 and the angle of view of the imaging unit 10 from the wall surface is a region representing the detection area of the PIR sensor on the monitoring image.

  In the present embodiment, the sensor unit 20 has a pan function and can rotate in the horizontal (left and right) direction with respect to the visual axis of the imaging unit 10. That is, the position of the area representing the detection area on the monitoring image is fixed in the vertical (vertical) direction and varies in the horizontal (horizontal) direction. The horizontal orientations of the sensor unit 20 and the imaging unit 10 are adjusted manually by the installer according to the installation environment of the intruding object detection device 1, but at least the imaging range of the imaging unit 10 is within the sensor unit 20. It is set to include the detection area. The imaging unit 10 may also be provided with a pan function so that the visual axis can be rotated in the horizontal direction with respect to the intruding object detection device 1. In addition, the sensor unit 20 and the imaging unit 10 may further include a tilt function, and the respective visual axes may be rotated in the vertical direction with respect to the intruding object detection device 1.

  The storage unit 30 includes a nonvolatile semiconductor memory such as a flash memory (registered trademark), a volatile semiconductor memory, a magnetic disk (HDD), an optical disk drive such as a CD-ROM and a DVD-RAM, and a recording medium thereof. And the memory | storage part 30 memorize | stores the positional information which shows the position of the area | region showing the detection area on a monitoring image. Furthermore, the storage unit 30 also stores a program executed on the monitoring processing unit 70, various setting parameters used by the program, a calculation value or an image obtained as a result of various processes or an intermediate result. Then, the storage unit 30 stores the calculated value or the image according to the control signal from the monitoring processing unit 70 or outputs various stored information to the monitoring processing unit 70.

  The operation unit 40 includes input devices such as a keyboard and a mouse, receives an operation for switching between a registration mode and a warning mode or various operations in the registration mode from an operator, and sends signals corresponding to those operations to the monitoring processing unit 70. Output.

  The display unit 50 is configured by a display device such as a liquid crystal display, displays various information received from the monitoring processing unit 70, and notifies the operator.

  The input of various operations and the display of various information may be realized by a terminal different from the intruding object detection device 1 such as a PDA (Personal Digital Assistants). In that case, the operation unit 40 and the display unit 50 communicate with a terminal such as a PDA via the communication unit 60 to input various operations and display various information.

  The communication unit 60 is an input / output interface that transmits and receives various setting signals and control signals between the intruding object detection device 1 and the security device 3 via a communication network such as the local area network 6. ) And the like, and driver software for driving them.

  The monitoring processing unit 70 has an embedded microprocessor unit and its peripheral circuits, and controls the entire intruding object detection apparatus 1. Further, in the registration mode, the monitoring processing unit 70 identifies an area representing a detection area on the monitoring image received from the imaging unit 10, and in the monitoring mode, the monitoring processing unit 70 includes a detection area in the detection area based on the detection level information received from the sensor unit 20. The presence of an intruding object is judged and an alarm is issued. For this purpose, the monitoring processing unit 70 includes area setting means 71 and abnormality monitoring means 76. Each of these units included in the monitoring processing unit 70 is implemented as, for example, a functional module of a program that operates on the microprocessor unit.

  The area setting unit 71 sets the detection area on the monitoring image based on the detection level information acquired from the sensor unit 20 and the monitoring image acquired from the imaging unit 10 when the worker is performing a walk test in the registration mode. Specify the area to represent. For this purpose, the area setting unit 71 includes a change area extraction unit 72, a human image position extraction unit 73, an area identification unit 74, and an area registration unit 75.

  The area setting unit 71 determines whether or not a walk test is being performed by receiving a signal indicating that a walk test start operation or end operation has been performed from the operation unit 40. Alternatively, the walk test may be automatically ended after a predetermined period of time has elapsed after receiving a signal indicating the start operation of the walk test.

  The change area extraction unit 72 extracts an area where the worker is captured from the monitoring image every time the imaging unit 10 acquires the monitoring image. For example, the change area extraction unit 72 uses a frame difference process or a background difference process to extract a change area having a temporal change in luminance value from a plurality of monitoring images continuously acquired by the imaging unit 10. To do. Then, the change area extraction unit 72 stores the extracted change area in the storage unit 30.

The human image position extraction unit 73 receives detection level information from the sensor unit 20 during execution of the walk test, and determines whether or not the detection level P is equal to or greater than a predetermined reference value Z1. Then, when the detection level P is equal to or higher than the reference value Z1, the human image position extracting unit 73 extracts the center of gravity position of the changed area extracted by the changed area extracting unit 72 at that time as the human image position and stores it in the storage unit 30.
In addition, the reference value Z1 is set to a value indicating that the detection level P has a person in the detection area. Also, in the walk test, it is preferable to make it easier to detect people than in the alert mode so that many samples can be acquired in a short time, and therefore the reference value Z1 is a threshold for determining an intruding object in the alert mode. The following values are preferable.

  Further, in the intruding object apparatus 1, since the sensor unit 20 and the imaging unit 10 operate at independent timings, the timing at which the sensor unit 20 outputs detection level information to the monitoring processing unit 70 and the imaging unit 10 acquire a monitoring image. Timing does not necessarily match. Therefore, the timing at which the human image position extracting unit 73 determines the detection level does not necessarily match the timing at which the change region extracting unit 72 acquires the image from which the change region is extracted. Therefore, the human image position extracting unit 73 extracts the human image position from the change area of the monitoring image immediately before it is determined that the detection level P is equal to or higher than the reference value Z1. Alternatively, the human image position extracting unit 73 extracts the human image position from the change area of the monitoring image immediately after determining that the detection level P is equal to or higher than the reference value Z1.

After the end of the walk test, the area specifying unit 74 analyzes the position of the human image stored in the storage unit 30 during the walk test, and determines the end of the movement range of the person restricted by the restriction that restricts the movement of the person. Detect on the monitoring image. The area specifying unit 74 specifies the position of the restriction object on the monitoring image from the end of the detected movement range of the person. In this embodiment, the wall of a house is assumed as a restriction | limiting object, and the area specification means 74 specifies the wall surface position which is a position where the wall surface was copied as a position of a restriction | limiting object. As shown in FIGS. 2B and 2C, in this embodiment, the imaging unit 10 is installed so as to capture the wall 220 of the house from the horizontal direction and the monitoring area from the horizontal direction. Therefore, the horizontal position at which the wall surface on the monitoring image is imaged does not differ greatly between the vicinity of the imaging unit 10 (lower side on the monitoring image) and the far side (upper side on the monitoring image). Therefore, the area specifying unit 74 specifies the wall surface position based on the horizontal position on the monitoring image.
As shown in FIGS. 2 (b) and 2 (c), when monitoring a wall, a person's movement range is limited by a wall surface at one end and not at the other end. Therefore, when a test walk is performed within the shooting range, the human image position when the person is detected by the sensor unit 20 is not likely to deviate from the actual human position on the wall side, and the movement is not hindered on the opposite side. Is likely to occur. Therefore, the area specifying unit 74 detects which end in the horizontal direction is on the wall side with respect to the movement range of the person during the walk test.

  In the present embodiment, the area specifying unit 74 first creates an appearance frequency distribution at each horizontal position on the monitoring image for the human image position stored in the storage unit 30. At this time, in order to reduce the influence of the measurement error, it is preferable that the area specifying unit 74 obtains the number of appearances of the human image position for each certain range. For example, the area specifying unit 74 divides the monitoring image into a plurality of areas having a predetermined width in the horizontal direction, and obtains the number of times the human image position is recorded for each divided area. Alternatively, the area specifying unit 74 may obtain the number of times the human image position is recorded in an area having a predetermined width centered on the horizontal position for each horizontal position on the monitoring image, and the number of appearances corresponding to each horizontal position may be used. .

  FIG. 3 shows an example of the appearance frequency distribution of human image positions. In FIG. 3, a graph 300 represents the appearance frequency distribution of the human image position on the monitoring image, the horizontal axis represents the horizontal position on the monitoring image, and the vertical axis represents the number of appearances of the human image position at each position. In the graph 300, the number of appearances of the human image position has a certain value or more in a certain range on the left side of the coordinate X1, but rapidly decreases at the coordinate X1, and becomes zero in the range on the right side of the coordinate X1. That is, in this case, it can be estimated that the worker has not moved to a location corresponding to the position on the right side of the coordinate X1, and the wall surface position X2 exists in the vicinity thereof.

Therefore, the area specifying unit 74 obtains a position (hereinafter referred to as an edge position) where the number of appearances rapidly decreases in the appearance frequency distribution of the created human image position. For example, the area specifying unit 74 sets a position where the number of appearances of the human image position is equal to or less than a predetermined number and decreases by a predetermined threshold or more with respect to the number of appearances of the human image position in the adjacent position as the edge position. Furthermore, it is preferable that the number of appearances at subsequent horizontal positions be 0 or a predetermined number or less. Alternatively, the area specifying unit 74 generates an approximate curve of the number of appearances of the human image position using a least square method or the like, and the value of the approximate curve at each horizontal position is equal to or less than a predetermined value, and the approximate curve at the adjacent position is used. A position that decreases by a predetermined threshold or more with respect to the value may be set as the edge position. Further, it may be added to the condition for determining the edge position that the appearance frequency continues at 0 or below a predetermined horizontal position after the position where the appearance frequency has rapidly decreased. It should be noted that these predetermined threshold values relating to the reduction range can be determined appropriately by, for example, performing a walk test by experiment and measuring the number of appearances of the human image position. Further, in this example, not only the reduction width but also the absolute number (value) at the horizontal position is not more than a predetermined value as a condition for the edge position. This is because the appearance frequency is 0 or a number (value) very close to 0 on the side where movement is restricted by the wall.
Note that, as shown in FIGS. 2B and 2C, in general, the imaging unit 10 covers a wider area on the side opposite to the wall 220 of the house so that the monitor can grasp the surrounding situation in more detail by the image. It is installed so that it may image. That is, when a wall surface is imaged in the right direction, the wall surface is imaged on the right side from the center position on the monitoring image, and when a wall surface is imaged on the left side, the wall surface is imaged on the left side from the center position on the monitoring image. The Therefore, the area specifying unit 74 detects the edge position based on the amount of decrease in the number of appearances of the human image position relative to the position adjacent to the left side in the region on the right side of the central position on the monitoring image, and from the central position on the monitoring image. In the left area, the edge position may be detected based on the amount of decrease in the number of appearances of the human image position relative to the position adjacent to the right side.

  Then, the area specifying unit 74 estimates that the obtained edge position is a wall surface position. In consideration of the fact that the worker does not move to a position in contact with the wall surface, the area specifying means 74 is the side where the number of appearances of the human image position is smaller than the obtained edge position, that is, the opposite side of the movement range of the person (see FIG. In the example shown in FIG. 3, the position shifted by a predetermined amount on the right side) may be estimated as the wall surface position. Note that this predetermined amount can also be determined as an appropriate value by, for example, performing a walk test by experiment and measuring the difference between the edge position and the wall surface position.

  The area specifying unit 74 then determines the viewing angle of the sensor unit 20 on the side where the number of appearances of the human image position from the estimated wall surface position, that is, the human movement range side (left side in the example shown in FIG. 3), An area having a size determined based on the angle of view or the like is specified as an area representing the detection area of the sensor unit 20. In the example illustrated in FIG. 3, the hatched portion 301 is specified as a region representing the detection area.

  When the edge position cannot be detected after the walk test is performed, the detection area of the sensor unit 20 is highly likely not to include an area along the wall surface. Therefore, if the edge position cannot be detected, the area specifying unit 74 displays on the display unit 50 that the detection area of the sensor unit 20 has not been set correctly and notifies the operator.

  The area registration unit 75 generates position information indicating the position of the area representing the detection area on the monitoring image specified by the area specifying unit 74 and registers the position information in the storage unit 30.

  Hereinafter, the processing in the registration mode controlled by the area setting means 71 will be described with reference to the flowchart shown in FIG. In the processing described below, the operator uses the operation unit 40 to perform a switching operation from the warning mode to the registration mode and a start operation of the walk test, and the area setting unit 71 receives signals corresponding to these operations. Is executed at the timing of receiving from the operation unit 40.

  The worker moves across the entire monitoring area after performing the start operation of the walk test using the operation unit 40. At this time, the human image position extraction unit 73 receives the detection level information from the sensor unit 20, and determines whether or not the detection level P is equal to or higher than the reference value Z1 (step S1). When the detection level P is less than the reference value Z1, the human image position extraction unit 73 returns the control to step S1 and waits until new detection level information is received from the sensor unit 20.

  On the other hand, when the detection level P becomes equal to or higher than the reference value Z1, the human image position extracting unit 73 extracts the center of gravity position of the changed area extracted by the changed area extracting unit 72 at that time as the human image position and stores it in the storage unit 30 ( Step S2). Thereafter, the human image position extracting means 73 determines whether or not the walk test is finished by the operator (step S3). If the human image position extracting unit 73 has not received a signal corresponding to the end operation of the walk test from the operation unit 40, the human image position extracting unit 73 returns the control to step S1 and repeats the processes of steps S1 to S3.

  On the other hand, when the human image position extracting unit 73 receives a signal corresponding to the end operation of the walk test from the operation unit 40, the area specifying unit 74 creates the appearance frequency distribution of the human image position stored in the storage unit 30 (step S4). When the area specifying unit 74 creates the appearance frequency distribution of the human image positions, the area specifying unit 74 obtains an edge position where the number of appearances rapidly decreases in the appearance frequency distribution of the created human image positions (step S5). Then, the area specifying unit 74 determines whether or not the edge position has been detected (step S6). When the area specifying unit 74 detects the edge position, the area specifying unit 74 estimates that the edge position or a position shifted from the edge position by a predetermined amount to the side where the human image position appears less frequently is the wall surface position. Then, the area specifying unit 74 sets an area having a size determined based on the viewing angle of the sensor unit 20, the angle of view of the imaging unit 10, and the like on the side where the appearance number of the human image position is large from the estimated wall surface position. The area is specified as a detection area (step S7).

  When the area specifying unit 74 specifies an area representing the detection area on the monitoring image, the area registration unit 75 generates position information indicating the position of the area and registers it in the storage unit 30 (step S8).

  On the other hand, if the edge position cannot be detected in step S6, the area specifying unit 74 displays on the display unit 50 that the detection area of the sensor unit 20 has not been set correctly and notifies the operator (step S9). ).

  Returning to FIG. 1, the abnormality monitoring unit 76 detects an intruding object that has entered the monitoring area based on the detection level information received from the sensor unit 20 in the alert mode. Then, when detecting the intruding object, the abnormality monitoring unit 76 transmits the intruding object detection signal and the monitoring image captured by the imaging unit 10 to the security device 3 via the communication unit 60.

  Hereinafter, processing in the alert mode controlled by the abnormality monitoring means 76 will be described with reference to the flowchart shown in FIG. The process described below is executed at the timing when the abnormality monitoring unit 76 receives the detection level information from the sensor unit 20.

  When the abnormality monitoring unit 76 receives the detection level information from the sensor unit 20, the abnormality monitoring unit 76 determines whether or not the detection level P is greater than or equal to a predetermined threshold Th (step S11). Note that the threshold value Th is set to a value indicating that an intruding object exists in the detection area based on experiments or experience. If the detection level P is equal to or greater than the threshold value Th, the abnormality monitoring unit 76 determines that there is an intrusion abnormality (step S12). When the abnormality monitoring unit 76 determines that there is an intrusion abnormality, the latest monitoring image captured by the imaging unit 10 (hereinafter, the latest monitoring image when the abnormality monitoring unit 76 determines that there is an intrusion abnormality or an obstacle abnormality described later is an abnormal image. (Hereinafter referred to as a composite image) in which the detection area of the sensor unit 20 is displayed (step S13). For example, the abnormality monitoring unit 76 reads the position information of the detection area of the sensor unit 20 from the storage unit 30, and combines a frame representing the range of the detection area with the abnormal image to obtain a composite image. Then, the abnormality monitoring unit 76 transmits the intruding object detection signal and the composite image to the security device 3 via the communication unit 60 (Step S14).

  On the other hand, when the detection level P is less than the threshold value Th, the abnormality monitoring unit 76 determines whether there is an obstacle that prevents the detection of the intruding object (step S15). For example, there is no problem even if a small obstacle such as a distant object is present, but the intruding object detection device 1 is covered with a cloth or the like due to malicious intention or a large obstacle is placed in the detection area. When an act is performed, there is a possibility that the intruding object detection device 1 cannot properly detect the intruding object. Therefore, the intruding object detection device 1 needs to notify the security device 3 when an obstacle appears in most of the area representing the detection area on the monitoring image. Therefore, the abnormality monitoring unit 76 extracts a change region having a temporal change in luminance value using inter-frame difference processing or background difference processing from a plurality of monitoring images continuously acquired by, for example, the imaging unit 10. Then, it is determined whether or not the extracted change area is a predetermined size or more. The predetermined size is set to a value indicating the size of an obstacle that prevents detection of an intruding object. This predetermined size is appropriately optimized according to the environment in which the intruding object detection device 1 is installed, the purpose of detecting the intruding object, and the like.

  If the abnormality monitoring unit 76 determines that there is no obstacle, the abnormality monitoring unit 76 returns the control to step S11. On the other hand, when the abnormality monitoring unit 76 determines that an obstacle exists, the abnormality monitoring unit 76 determines whether the obstacle exists in the detection area (step S16). For example, the abnormality monitoring unit 76 determines whether or not an obstacle exists in the detection area based on whether or not the change area extracted from the monitoring image overlaps the range of the detection area.

  If the abnormality monitoring unit 76 determines that there is no obstacle in the detection area, the abnormality monitoring unit 76 returns the control to step S11. On the other hand, if the abnormality monitoring unit 76 determines that an obstacle exists in the detection area, it determines that the obstacle is abnormal (step S17). When the abnormality monitoring unit 76 determines that the obstacle is abnormal, the abnormality monitoring unit 76 generates a composite image (step S18), and transmits the obstacle detection signal and the composite image indicating that the obstacle has been detected via the communication unit 60 to the security device 3. (Step S19).

  The abnormality monitoring unit 76 does not synthesize a frame representing the range of the detection area with the abnormal image, and transmits the position information of the abnormal image and the detection area together with the intruding object detection signal or the obstacle detection signal to the communication unit 60. It may be transmitted to the security device 3 via the network. In that case, the security device 3 generates a composite image from the abnormal image and the position information of the detection area, and transmits the composite image to the monitoring center device 5. Alternatively, the security device 3 transfers the abnormal image and the position information of the detection area, and synthesizes and displays the information in the monitoring center device 5.

  Further, when the security device 3 receives the intruding object detection signal or the obstacle detection signal and the composite image, the security device 3 may transfer the received composite image to the operation display 4 and cause the operation display 4 to display the composite image. .

  In addition, the abnormality monitoring unit 76 generates an image in which a frame representing the range of the detection area is combined with the latest monitoring image captured by the imaging unit 10 in response to a request from the security device 3 or the operation display 4. You may transmit to the security apparatus 3 or the operation indicator 4. Thereby, the security device 3 can transmit the image which combined the detection area to the monitoring center apparatus 6 according to the request | requirement from the monitoring center apparatus 6, and the operation indicator 4 is the range of a detection area according to a user's operation. Can be displayed.

  As described above, in the intruding object detection device according to the present invention, the human image position extraction unit 73 determines the presence or absence of an intruding object based on the detection level information acquired from the sensor unit 20, and determines that the intruding object exists. The human image position is extracted based on the change area on the monitoring image. Then, the area specifying unit 74 detects an end portion on the wall side in the movement range of the person on the monitoring image based on the appearance frequency distribution of the human image position, and further specifies a region representing the detection area on the monitoring image. Thereby, the intruding object detection device can statistically obtain a region representing the detection area on the monitoring image, and can specify the range of the detection area with high accuracy.

  Furthermore, if the characteristic of the moving range close to the wall surface is not obtained from the appearance frequency distribution, the area specifying unit 74 displays on the display unit 50 that the detection area of the sensor unit 20 has not been set correctly, and prompts the operator. Inform. Thereby, the intruding object detection device can prevent an artificial setting error regarding the direction of the PIR sensor, and can improve the reliability of intrusion monitoring.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to these embodiments. For example, each time the human image position extraction unit 73 acquires a monitoring image from the imaging unit 10, the human image position is extracted and stored in the storage unit 30 regardless of the value of the detection level P. Even after the edge position is detected, it may be determined whether or not the human image position exists further on the wall surface side than the detected edge position. Then, when the human image position is further on the wall surface side than the detected edge position, the area specifying means 74 determines that the detection area of the sensor unit 20 has not been set correctly, and displays that fact on the display unit 50 for work. Inform the person. Thereby, the intruding object detection device can prevent an artificial setting error regarding the direction of the PIR sensor, and can improve the reliability of intrusion monitoring.

  Moreover, in this embodiment, the abnormality monitoring means 76 transmits the obstacle detection signal which shows having detected the obstacle to the guard apparatus 3 only when it determines with an obstacle existing in the detection area of the sensor part 20. However, the present invention is not limited to this. For example, even when the abnormality monitoring unit 76 determines that an obstacle does not exist in the detection area of the sensor unit 20, the abnormality monitoring unit 76 determines that there is a plan action and transmits an obstacle detection signal to the security device 3. Also good.

  In this embodiment, the example of obtaining the position of the detection area in the horizontal direction on the image has been described. However, a predetermined direction is determined according to the positional relationship between the imaging direction, the wall that is a restriction, and the detection area, such as the vertical direction and the oblique direction. It can be realized by replacing the direction. Moreover, you may use not only one direction but two directions.

In another embodiment, the end of the movement range of a person may be estimated using a peak distribution of detection levels instead of an appearance frequency distribution of human image positions. The entire configuration of the intruding object detection device in this case is the same as that shown in FIG. 1, and is realized by the human image position extraction means 73 and the area specifying means 74, as compared with the intruding object detection device according to the above embodiment. Only the function to be different is different. Therefore, only the differences from the intruding object detection device according to the above embodiment will be described below. The human image position extraction unit 73 determines whether or not the detection level P received from the sensor unit 20 is equal to or higher than a predetermined reference value Z2 during the walk test. Then, when the detection level P is greater than or equal to the reference value Z2, the human image position extraction unit 73 extracts the center of gravity position of the change area extracted by the change area extraction unit 72 at that time as the human image position, and the detection level P at that time The data are stored in the storage unit 30 in association with each other.
The reference value Z2 is set to a value indicating that an intruding object is present in the detection area, similarly to the reference value Z1. Further, the reference value Z2 is preferably set to a value lower than the threshold value Th for determining an intruding object in the alert mode so that the change in the detection level P at each position can be observed.

  In this embodiment, after the end of the walk test, the area specifying unit 74 creates a peak distribution of detection levels at each horizontal position on the monitoring image based on the human image position and the detection level P stored in the storage unit 30. . For example, the area specifying unit 74 divides the monitoring image into a plurality of regions having a predetermined width in the horizontal direction, and for each divided region, the highest detection level P associated with the human image position indicating the position in the region. The value is extracted and set as a peak value. Alternatively, the area specifying unit 74 extracts, for each horizontal position on the monitoring image, the highest value among the detection levels P associated with the human image position recorded in a predetermined width area centered on the horizontal position, It may be a peak value corresponding to each horizontal position.

  FIG. 6 shows an example of a peak distribution of detection levels. In FIG. 6, a graph 600 represents a peak distribution of detection levels on the monitoring image, a horizontal axis represents a horizontal position on the monitoring image, and a vertical axis represents a peak value of the detection level at each position. In the graph 600, a range indicated by a solid line, that is, a range having a value equal to or higher than the threshold value Z2 indicates a region where a peak value is actually extracted. In the graph 600, the peak value of the detection level has a value greater than or equal to a certain value in a certain range on the left side of the coordinate X3, but rapidly decreases at the coordinate X3 and becomes zero in the range on the right side from the coordinate X3. That is, in this case, it can be estimated that the worker has not moved to a position corresponding to the position on the right side of the coordinate X3, and the wall surface position X4 exists in the vicinity of the coordinate X3.

Therefore, the area specifying unit 74 obtains an edge position where the peak value rapidly decreases with respect to the created peak distribution of the detection level. For example, the area specifying unit 74 sets a position where the peak value of the detection level at each horizontal position decreases by a predetermined threshold or more with respect to the peak value of the detection level at the adjacent position. Alternatively, the area specifying unit 74 generates an approximate curve of the peak value of the detection level using the least square method or the like, and the value by the approximate curve at each horizontal position is predetermined with respect to the value by the approximate curve at the adjacent position. A position that decreases more than a threshold value may be used as the edge position. Further, it may be added to the edge position determination condition that the peak value continues at 0 or a predetermined value or less at the horizontal position after the position where the peak value has suddenly decreased. Note that these predetermined threshold values can be determined appropriately by, for example, performing a walk test by experiment and measuring the peak value of the detection level.
In addition, the area specifying unit 74 detects an edge position based on the decrease amount of the peak value of the detection level with respect to the position adjacent to the left side in the region on the right side of the center position on the monitoring image, and from the center position on the monitoring image. In the left area, the edge position may be detected based on the decrease amount of the peak value of the detection level with respect to the position adjacent to the right side.

  Then, the area specifying unit 74 estimates that the wall position is a determined edge position or a position shifted by a predetermined amount from the edge position to the side where the peak value of the detection level is small, that is, the opposite side of the human movement range. Then, the area specifying unit 74 specifies a region having a predetermined size on the side where the peak value of the detection level is large from the estimated wall surface position, that is, the human movement range side, as a region representing the detection area of the sensor unit 20. In the example illustrated in FIG. 6, the hatched portion 601 is specified as a region representing the detection area.

  FIG. 7 shows a flowchart in a case where the area setting means 71 specifies a region representing a detection area using the peak distribution of detection levels.

  In step S21 of the flowchart shown in FIG. 7, the human image position extracting unit 73 receives the detection level information from the sensor unit 20 as in step S1 shown in FIG. 4, and whether or not the detection level P is equal to or higher than the reference value Z2. Is determined (step S21). Then, when the detection level P becomes equal to or higher than the reference value Z2, the human image position extracting unit 73 extracts the center of gravity position of the changed area extracted by the changed area extracting unit 72 at that time as the human image position and stores it in the storage unit 30 (step S22). Thereafter, the human image position extracting means 73 determines whether or not the walk test has been finished by the operator (step S23).

When the human image position extracting unit 73 receives a signal corresponding to the end operation of the walk test from the operation unit 40, the area specifying unit 74 detects based on the human image position and the detection level P stored in the storage unit 30. A level peak distribution is created (step S24). After creating the peak distribution of the detection level, the area specifying unit 74 obtains an edge position where the peak value rapidly decreases with respect to the created peak distribution of the detection level (step S25).
Since the process of step S26-S29 is the same as the process of step S6-S9 shown in FIG. 4, description is abbreviate | omitted.

  In this embodiment, the area specifying unit 74 detects the end of the movement range of the person on the captured image based on the peak value of the detection level detected by the sensor unit 20 at each position on the captured image. An area representing a detection area on the captured image is specified. The intruding object detection device can reduce the influence of the measurement error of the thermal change in the detection area by obtaining the peak value of the detection level at each position on the captured image, and the range of the detection area on the captured image. Can be accurately identified.

  As described above, those skilled in the art can make various modifications in accordance with the embodiment to be implemented within the scope of the present invention.

DESCRIPTION OF SYMBOLS 1, 2 Intruding object detection apparatus 3 Security apparatus 4 Operation indicator 5 Monitoring center 6 Local area network 7 Wide area communication network 10 Imaging part 20 Sensor part 30 Memory | storage part 40 Operation part 50 Display part 60 Communication part 70 Monitoring process part 71 Area setting Means 72 Change area extraction means 73 Human image position extraction means 74 Area identification means 75 Area registration means 76 Abnormality monitoring means 100 Security system

Claims (4)

A sensor unit that outputs a detection level corresponding to a heat ray radiated from the detection area, and a monitoring area that includes the restriction object and the detection area. An intruding object detection device that identifies an area corresponding to the detection area on the monitoring image by a test walk by a human,
A region extracting means for extracting a region corresponding to a person in the monitoring image;
The position of the region extracted from the monitoring image acquired by the imaging unit when the detection level output by the sensor unit is a value indicating that a person is present in the detection area is a human image position. Human image position extracting means for extracting;
Based on a plurality of the human image positions extracted by the human image position extracting means during a predetermined period, an end of the movement range of the person limited by the restricted object is detected on the monitoring image, and An area specifying means for specifying an area representing the detection area on the monitoring image using an end as one end of the detection area;
An intruding object detection device comprising:   The area specifying means obtains the appearance frequency of the human image position extracted during the predetermined period for each position on the monitoring image, and sets a position where the appearance frequency rapidly decreases with respect to an adjacent position as the moving range. The intruding object detecting device according to claim 1, wherein the intruding object detecting device is an end of the intruding object. The human image position extracting means stores the human image position and the detection level in association with each other when the detection level is a value indicating that a person exists in the detection area,
2. The intrusion according to claim 1, wherein the area specifying unit sets a position at which the detection level stored in association with the human image position on the monitoring image rapidly decreases with respect to an adjacent position as an end of the moving range. Object detection device. Furthermore, it has a display part,
The said area specification means displays on the said display part that the said detection area set to the said sensor part is not correct, when the said edge part cannot be specified on the said monitoring image. The intruding object detection device described.

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