JP2009002914A - Facility disaster monitoring device and facility disaster monitoring method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To always grasp the disaster status of an objective monitoring facility due to earthquake correctly without always or highly frequently capturing images of the facility with a camera. <P>SOLUTION: The receiver 7 receives urgent earthquake news flash, the camera 1 is activated by the urgent earthquake news flash as a trigger so as to capture image of the objective monitoring facility and then monitors the arrival of the main movement of the earthquake from the earthquake detection signal outputted from the earthquake sensor 8 arranged nearby the objective monitoring facility. After the detection of the arrival of the main movement, the camera 1 is made to operate to capture image of the objective monitoring facility, then the absolute difference value C between each monitoring image data A and B are calculated, the calculated absolute difference value C is compared with the previously set threshold value d, the disaster of the objective monitoring facility is determined from the result of the comparison and the monitoring center CT is informed of the result by the electronic mail. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an apparatus and method for monitoring the state of a facility such as a building, a bridge, or a plant facility outdoors using a camera.

  2. Description of the Related Art Conventionally, an apparatus that uses a camera to image a facility such as a building or a bridge or an industrial plant facility and monitors the abnormality of the facility based on the image data has been used. When this type of equipment is installed, if an abnormality such as damage occurs in a facility due to natural disasters such as earthquakes, typhoons, lightning strikes, or accidents such as collisions or explosions, the situation is remotely monitored to take prompt measures. It can be taken and is very useful.

  By the way, in this type of monitoring apparatus, for example, the facility to be monitored is imaged with a camera at all times or at regular time intervals, the image data is sequentially accumulated, and changes between these image data are detected by image processing. , Trying to detect abnormalities in the facility. In order to prevent erroneous detection due to changes in sunshine conditions, for example, an illuminometer is installed near the camera to detect the brightness around the monitored object, and the brightness of the monitored object is detected according to the detected brightness value. Then, three types of evening reference images are selected, and a change in the image is detected by comparing the captured image with the selected reference image (see, for example, Patent Document 1).

Japanese Patent No. 2947689

  However, natural disasters do not occur frequently. Nevertheless, it is wasteful to capture the facility to be monitored with a camera at all times or at regular time intervals and sequentially store the image data. In particular, since a large-capacity memory is required for storing image data, this causes an increase in size and cost of the apparatus. On the other hand, if the imaging interval of the monitored facility is set to be long in order to reduce the memory capacity, the probability that the monitoring image cannot be acquired at an appropriate timing before and after the occurrence of a sudden natural disaster such as an earthquake This increases the monitoring performance.

  The present invention has been made paying attention to the above circumstances, and the purpose of the present invention is to be able to always accurately grasp the state of damage caused by an earthquake without constantly or frequently imaging the facility to be monitored with a camera. Accordingly, it is an object to provide a facility damage monitoring apparatus and a facility damage monitoring method that are small and inexpensive and have excellent monitoring performance.

  In order to achieve the above object, one aspect of the present invention is to receive an earthquake early warning and operate the camera for a period of time from the time when the earthquake early warning is received until the main motion of the earthquake arrives. Then, the facility to be monitored is imaged, whereby the first image data is acquired and stored. Subsequently, based on the earthquake detection signal output from the seismic sensor installed in the vicinity of the monitored facility, the presence or absence of the arrival of the main motion of the earthquake is monitored. The facility is operated again for a limited time to capture the monitored facility, and the second image data is acquired and stored. Then, difference information between the obtained first and second image data is calculated, the calculated difference information is compared with a preset threshold value, and the monitoring is performed based on the comparison result. The presence or absence of a change in the target facility is determined.

  Therefore, the imaging operation of the facility to be monitored is performed when the earthquake early warning is received and after the main motion arrives. For this reason, the image data obtained by imaging the monitoring target facility is only the image data obtained by the above two imaging operations. Therefore, the capacity of the image memory can be greatly reduced as compared with the case where the monitored facility is imaged constantly or frequently. In addition, since the captured image data of the monitoring target facility can always be obtained at the optimal timing before and after the occurrence of the earthquake, it is possible to always reliably determine the damage status of the monitoring target facility.

The present invention is also characterized by further comprising the following specific viewpoints.
According to the first aspect, when the first image data is acquired and stored, the seismic intensity of the main motion is estimated from the content of the received earthquake early warning, and the estimated threshold value of the seismic intensity is set in advance. When the value is greater than or equal to the value, the camera is operated for a limited time to image the monitored facility.
In this way, instead of starting with all earthquake early warnings, the monitored facility is only activated when an emergency earthquake warning is received that reports the occurrence of a relatively large earthquake that could cause damage to the monitored facility. An imaging operation is performed. For this reason, the imaging operation can be limited only when necessary.

The second aspect is to measure the actual seismic intensity of the main motion based on the seismic detection signal of the seismic sensor and to acquire and store the second image data when detecting the arrival of the main motion. When the estimated seismic intensity of the main motion is determined to be greater than or equal to the first threshold and the actual seismic intensity measurement of the main motion is greater than or equal to the second threshold, It is made to operate again to image the facility to be monitored.
In this way, the monitored facility is imaged only when the magnitude of the earthquake notified by the emergency earthquake warning is large and the actual seismic intensity of the reached main motion is also large. For this reason, it is possible to further reduce the occurrence of substantially unnecessary imaging operations.

According to a third aspect, when calculating the difference information between the first image data and the second image data, the brightness of the first image data and the second image data is equalized prior to that. An image density normalization process is performed on the first and second image data.
In this way, even if the brightness between the first image data and the second image data is different due to a sudden change in sunshine conditions such as the weather or the occurrence of a fire, the image density normalization process performs this process. The difference is obtained after the brightness difference is corrected. For this reason, it is possible to monitor at low cost and with high accuracy without installing an accessory device such as an illuminometer and eliminating the influence of sunlight and fire on the image.

According to a fourth aspect, when an image density normalization process is performed, an average value of image densities of each pixel or pixel block of the first image data is calculated, and each pixel or pixel block of the second image data is calculated. The average value of the image densities is calculated. Then, based on the calculated average value of the image density of the first image data and the average value of the image density of the second image data, the first and the second values are set so that these average values are arbitrary common values. Image density correction processing is performed for each pixel or pixel block of the second image data.
Therefore, after the brightness of the first and second image data is corrected for each pixel or each pixel block, the difference is taken. For this reason, it is possible to perform appropriate illuminance correction over the entire area of the image data, and thereby it is possible to accurately determine the change over the entire monitoring object.

According to a fifth aspect, when performing normalization processing of image density, the normalization processing is performed for each pixel element of R, G, and B, and when obtaining difference information, between the first and second image data Is obtained for each of the R, G, and B pixel elements. The obtained difference information is compared with a threshold value for each of the R, G, and B pixel elements, and if any one or two or more of the respective pixel elements are equal to or greater than the threshold value, the monitored facility Is determined to have changed.
Therefore, when the change of the monitoring object is determined based on the color image, the change in the brightness of the image data due to the change in the sunshine condition is corrected for each of the R, G, and B pixel elements. , B is determined in consideration of the brightness of each pixel element. As a result, even when a color image is used, it is possible to make an optimal determination in consideration of changes in sunshine conditions.

A sixth aspect is that when it is determined that there is a change in the facility to be monitored, between the corresponding first and second image data and the first and second image data calculated by the difference calculation. The difference information is transmitted via a communication network to a terminal device of a manager in charge set in advance as a notification destination.
Therefore, only when a significant change is found in the image data, the corresponding first and second image data are sent to the manager. For this reason, the traffic of the communication network can be suppressed, and the burden on the monitoring work of the manager can be reduced. Moreover, since the difference information is also sent in addition to the first and second image data, it is possible to confirm the change occurrence site in the screen at a glance.

  In short, according to one aspect of the present invention, it is possible to always accurately grasp the state of damage caused by an earthquake without constantly or frequently imaging a facility to be monitored by a camera, thereby making it possible to monitor in a small and inexpensive manner. A facility damage monitoring apparatus and a facility damage monitoring method having excellent performance can be provided.

Embodiments according to the present invention will be described below with reference to the drawings.
FIG. 1 is a schematic configuration diagram of a monitoring system including a facility damage monitoring apparatus according to an embodiment of the present invention. In the figure, for example, facility damage monitoring devices DS1 to DSn are fixed in places where the monitoring target facilities TG1, TG2,. Is installed. Any of these facility damage monitoring apparatuses DS1 to DSn can communicate with the management center CT via the communication network NW.

  In the management center CT, for example, a management terminal composed of a personal computer is installed. This management terminal stores the function of remotely controlling the facility damage monitoring devices DS1 to DSn via the communication network NW and the monitoring image data sent from the facility damage monitoring devices DS1 to DSn via the communication network NW. It has a function to display on the display later.

  The communication network NW includes, for example, an IP (Internet Protocol) network represented by the Internet and a plurality of access networks for accessing the IP network. As the access network, for example, a DSL (Digital Subscriber Line) or a wired subscriber network using an optical transmission line, a LAN (Local Area Network), a wireless LAN, a mobile communication network, or a dedicated line network is used.

  By the way, the facility damage monitoring apparatuses DS1 to DSn are configured as follows. FIG. 2 is a block diagram showing the configuration. That is, each of the facility damage monitoring apparatuses DS1 to DSn includes a camera 1 including an industrial television camera, a camera interface (camera I / F) 2 for operating the camera 1, a control unit 3, a storage unit 4, An image processing unit 5, a communication unit 6, a receiver 7 for receiving an earthquake early warning, and an earthquake sensor 8 are provided.

  Among these, the camera I / F 2 operates the camera 1 under the control of the control unit 3 to image the monitoring target facilities TG1 to TGn, and transfers the captured image data to the control unit 3. The storage unit 4 uses, for example, a hard disk or a NAND flash memory as a storage medium, and stores the image data of the monitoring target facilities TG1 to TGn captured by the camera 1 under the control of the control unit 3. The communication unit 6 transmits / receives control signals and image data to / from a management terminal of the management center CT under the control of the control unit 3 in accordance with a communication method defined by the communication network NW.

For example, the receiver 7 receives an earthquake early warning transmitted from the Japan Meteorological Agency via a communication medium or a broadcast medium, and inputs the received earthquake early warning to the control unit 3. Earthquake early warning is the calculation of the location of the earthquake and the magnitude of the earthquake based on the detection results when the seismic wave (P wave) is detected by multiple seismometers for breaking news near the epicenter. Based on the results, the arrival time and seismic intensity of the main motion (S wave) are estimated, and the estimated information is used as an earthquake early warning before the main motion of the seismic wave (S wave) arrives. (For example, companies that operate and manage lifelines such as electricity, gas, water, communications, and railways, and companies that have semiconductor manufacturing lines and precision equipment manufacturing lines) It is scheduled to be provided to general users through institutions, broadcasters, and telecommunications carriers.
The earthquake sensor 8 is installed in the vicinity of the monitoring target facilities TG1 to TGn, mainly detects the main motion (S wave) of the seismic wave and inputs the detection signal to the control unit 3.

  The control unit 3 has, for example, a CPU (Central Processing Unit) composed of a microcomputer, and comprehensively controls the operations of the facility damage monitoring apparatuses DS1 to DSn. The control unit 3 includes a breaking news analysis module 31, a damage determination module 32, a camera control module 33, and a communication control module 34 as control functions according to the present invention. Each of these control modules 31 to 34 is realized by causing the CPU to execute an application program.

  The breaking news analysis module 31 takes in the earthquake early warning received by the receiver 7 and compares the estimated seismic intensity of the main motion in the area included in this emergency earthquake breaking news with the threshold value α, so that the estimated seismic intensity is the threshold. It is determined whether or not the value is greater than or equal to α. Here, for example, the threshold value α is set to “seismic intensity 4” which is a lower limit value of the seismic intensity at which the monitored facility may be damaged.

  The damage determination module 32 measures the actual seismic intensity of the main motion based on the detection signal of the earthquake sensor 8, and compares the actual seismic intensity measurement value with the threshold value β to determine the magnitude relationship. If the estimated seismic intensity is determined to be greater than or equal to the threshold value α by the breaking news analysis module 31 and the measured value of the actual seismic intensity of the main motion is also determined to be greater than or equal to the threshold value β, the monitored facility may have been damaged. Judge that there is sex. Here, the threshold value β is also set to “seismic intensity 4” which is the same as the threshold value α, for example.

  The camera control module 33 operates the camera 1 through the camera I / F 2 during a period until the main motion reaches when the estimated seismic intensity is determined to be greater than or equal to the threshold value α by the breaking news analysis module 31. The camera 1 is caused to capture the appearance of the monitored facility in the still image mode. Then, the image data captured by the camera 1 is taken in via the camera I / F 2, and this image data is stored in the storage unit 4 as the monitoring image data A immediately before the main movement is reached.

The camera control module 33 determines that there is a possibility that the monitored facility has been damaged by the damage determination module 32, that is, the estimated seismic intensity of the main motion is determined to be greater than or equal to the threshold value α, and When it is determined that the actual seismic intensity measurement value is equal to or greater than the threshold value β, the camera 1 is operated again via the camera I / F 2 after the main motion has converged, and the camera 1 is configured to display the appearance of the monitored facility in the still image mode. Let's take an image. Then, the image data captured by the camera 1 is taken in via the camera I / F 2, and this image data is stored in the storage unit 4 as the monitoring image data B immediately after reaching the main motion.
Further, the camera control module 33 transfers the monitoring image data A immediately before the arrival of the main movement and the monitoring image data B immediately after the arrival of the main movement to the image processing unit 5, and performs a difference detection process between the two image data described later, The difference determination process is performed.

  When the communication control module 34 is notified of a determination result indicating that a significant change has been detected from the image processing unit 5, the monitoring image data A and the main motion arrival just before reaching the main motion used for the difference detection are reported. The monitoring image data B immediately after is read out from the storage unit 4 and difference information between these image data A and B is taken in from the image processing unit 5. Then, the monitoring image data A immediately before the arrival of the main motion, the monitoring image data B immediately after the arrival of the main motion, and the difference information captured from the image processing unit 5 are attached to the e-mail and sent from the communication unit 6 to the monitoring center. Send to CT.

  When the communication control module 34 is notified of a determination result indicating that no significant change has been detected from the image processing unit 5, the communication control module 34 reads out the monitoring image data B immediately after reaching the main motion from the storage unit 4, The read monitoring image data B immediately after reaching the main motion is attached to an e-mail and transmitted from the communication unit 6 to the monitoring center CT.

The image processing unit 5 includes, for example, a DSP (Digital Signal Processor), and includes a difference detection module 51 and a residual determination module 52 as image processing functions according to the present invention.
The difference detection module 51 performs a process of detecting difference information C transferred from the camera control module 33 between the monitoring image data A immediately before the arrival of the main motion and the monitoring image data B immediately after the arrival of the main motion. Prior to that, image density normalization processing is performed on the monitoring image data A immediately before the arrival of the main motion and the monitoring image data B immediately after the arrival of the main motion so that the brightness of both data is equal.

  In this image density normalization process, the average value of the image density is calculated for each of the R, G, and B pixel elements for each of the monitoring image data A immediately before the arrival of the main motion and the monitoring image data B immediately after the arrival of the main motion. Based on the processing and the average value of the calculated image density of each of the monitoring image data A and B, R, G is applied to each of the monitoring image data A and B so that these average values are arbitrary common values. , B is a process for correcting the image density for each pixel element.

  The residual determination module 52 compares the difference value calculated for each of the R, G, and B pixel elements by the difference detection module 51 with a preset threshold value. Then, the difference value is equal to or greater than the threshold value in two or more of each of the R, G, and B pixel elements, and a pixel in which the difference value is determined to be equal to or greater than the threshold value is detected over a predetermined size region. In this case, a process of giving a notification signal to the communication control module 34 of the control unit 3 that a change has been detected between the monitoring image data A immediately before the arrival of the main motion and the monitoring image data B immediately after the arrival of the main motion is executed. To do.

Next, the monitoring operation in the facility damage monitoring apparatuses DS1 to DSn configured as described above will be described. FIG. 3 is a flowchart showing control procedures and control contents of the control unit 3 and the image processing unit 5 of the facility monitoring devices DS1 to DSn.
In the standby state, the facility damage monitoring devices DS1 to DSn are in an operation stop (sleep) state except for some functions of the receiver 7 and the control unit 3. That is, the camera 1 is in an operation stop state. In this state, the control unit 3 monitors the arrival of the earthquake early warning in step S11.

  Now, let us assume that an earthquake has occurred and an emergency earthquake bulletin has been sent from the Japan Meteorological Agency, for example. In this case, the facility damage monitoring devices DS <b> 1 to DSn receive the emergency earthquake bulletin by the receiver 7 and transmit it to the control unit 3. When the earthquake early warning is received, the control unit 3 proceeds from step S11 to step S12. First, the control unit 3 extracts an estimated seismic intensity (preliminary seismic intensity) of the main motion from the received emergency earthquake early warning, and this estimated seismic intensity is previously stored. Compare with the set threshold value α. For example, the threshold value α is set to “seismic intensity 4”, which is the lower limit value of the seismic intensity at which the monitored facility may be damaged, and the estimated seismic intensity is compared with this “seismic intensity 4”. If the estimated seismic intensity is less than “seismic intensity 4” as a result of this comparison, it is determined that monitoring of the monitored facility is unnecessary, and the apparatus returns to the standby state.

  In contrast, assume that the estimated seismic intensity is “seismic intensity 4” or more. In this case, the control unit 3 determines that the monitoring target facilities TG1 to TGn may be damaged, and sets the notice flag to ON in step S13. In step S14, an activation instruction is output to the camera I / F 2 before the main movement arrives. As a result, the camera 1 is activated by the camera I / F 2 and the monitoring target facilities TG1 to TGn are imaged by the camera 1. The control unit 3 captures the captured image data (still image data) via the camera I / F 2 and stores this image data in the storage unit 4 as the monitoring image data A immediately before reaching the main motion. At this time, the control unit 3 generates time stamp information indicating the imaging date and time of the monitoring image data A based on the time measured by the built-in clock, and assigns the time stamp information to the monitoring image data A and stores it.

  Next, in step S15, the control unit 3 continuously takes in the detection signal of the earthquake sensor 8, and measures the actual seismic intensity of the main motion based on the detection signal. In step S16, the measured seismic intensity is compared with a threshold value β. For example, the threshold value β is also set to “seismic intensity 4” which is the same as the threshold value α, and the measured seismic intensity is compared with this “seismic intensity 4”. If the measured seismic intensity is less than “seismic intensity 4” as a result of this comparison, it is determined that monitoring of the monitored facility is unnecessary, and the process returns to the standby state.

  On the other hand, suppose that the measured seismic intensity is “seismic intensity 4” or more. In this case, the control unit 3 determines that there is a possibility that the monitoring target facilities TG1 to TGn have been damaged, and sets the damaged flag to ON in step S17. Then, after confirming that the main motion has converged based on the detection signal of the earthquake sensor 8, an activation instruction is output to the camera I / F 2 in step S18. As a result, the camera 1 is activated again by the camera I / F 2, and the monitoring target facilities TG <b> 1 to TGn are imaged by the camera 1. The control unit 3 captures the captured image data (still image data) via the camera I / F 2 and stores this image data in the storage unit 4 as the monitoring image data B immediately after reaching the main motion.

  At this time, the control unit 3 generates time stamp information indicating the imaging date and time of the monitoring image data B based on the time measured by the built-in clock, and assigns the time stamp information to the monitoring image data B and stores it. To do. In addition, a common identification code is assigned to the monitoring image data B immediately after the arrival of the main motion in order to associate with the monitoring image data A immediately before the arrival of the main motion.

  Next, in step S19, the control unit 3 reads the monitoring image data A immediately before the arrival of the main motion and the monitoring image data B immediately after the arrival of the main motion, to which the common identification code is assigned, from the storage unit 4, respectively. Data A and B are transferred to the image processing unit 5 together with an image processing instruction.

  When the image processing instruction is received from the control unit 3, the image processing unit 5 first, in the difference detection module 51, as shown in step S20, the monitoring image data A just before the arrival of the main motion transferred together with the image processing instruction Difference information C from the monitoring image data B immediately after the arrival of the main motion is calculated.

First, the difference detection module 51 performs brightness correction processing on the monitoring image data A immediately before the arrival of the main motion and the monitoring image data B immediately after the arrival of the main motion by the brightness correction processing function as follows.
That is, for example, if the brightness (density) of each pixel of the image data is L1 to Ln (n = 256 if 16 × 16 pixels), the average M of the brightness (density) of the image data is
M = Σ (L1 to Ln) / n
It is expressed. Accordingly, the average brightness MA and MB are calculated for each of the monitoring image data A immediately before the arrival of the main motion and the monitoring image data B immediately after the arrival of the main motion.

Subsequently, the brightness (density) of each pixel of each of the monitoring image data A and B is set so that the average brightness MA and MB of each of the monitoring image data A and B becomes an arbitrary common value N. LAn and LB1 to LBn are corrected. This correction process
Monitoring image data A: LA1 × (N / MA) to LAn × (N / MA)
Monitoring image data B; LB1 × (N / MB) to LBn × (N / MB)
It is performed by the operation. When the monitoring image data A and B are color images, the brightness correction process is performed for each of the R, G, and B elements.

Next, the difference detection module 51 generates an absolute difference image C representing the difference between the monitoring image data AN and BN after the brightness is corrected by the difference calculation processing function. The absolute difference image C is generated for each pixel.
LC1 to LCn = | LA1−LB1 | 〜 | LAn−LBn |
The subtraction process is performed. When the corrected monitoring image data AN and BN are color images and the brightness is corrected for each of the R, G and B elements, the subtraction process for generating the absolute difference image C is performed. Is performed for each element of R, G, and B.

  Next, the image processing unit 5 supplies the absolute difference image C calculated by the difference detection module 51 to the residual determination module 52. In step S21, the residual determination module 52 compares the supplied absolute difference image C with a threshold value d set in advance for each pixel. This threshold value d is set to, for example, 1/10 of the maximum brightness value Lmax in the monitor image data AN whose brightness has been corrected.

  The threshold value d is set to a value smaller than 1/10 when a minute change between the monitoring images AN and BN is to be detected, while reducing the influence of noise components included in the image data. In order to detect only a more reliable change, a value larger than 1/10 may be set. When the absolute difference image C is generated for each element of R, G, B in the difference detection module 51, the residual determination module 52 sets the absolute difference image C for each element of R, G, B. Compare with thresholds dR, dG, dB.

  In step S22, the residual determination module 52 notifies the control unit 3 of information representing the comparison result between the absolute difference image C and the threshold value d. As a result of the comparison by the residual determination module 52, the control unit 3 has detected that a significant change has been detected in the monitoring image when the region where the pixels satisfying C> d are present over a wider range than the predetermined range. to decide. For example, in FIG. 4A, no significant change is detected between the monitoring image data A and the monitoring image data B, and in FIG. 4B, there is a significant difference between the monitoring image data A and the monitoring image data B. The case where a change is detected is shown.

  In the residual determination module 52, when the absolute difference image C is compared with the threshold values dR, dG, dB for each of the R, G, B elements, the control unit 3 has R, G, B, for example. If any one of the three elements, or two or more elements are larger than the threshold value and the area is wider than the predetermined range, it may be determined that a change has been detected in the monitoring image. Good.

When a significant change is detected in the absolute difference image C as in the case illustrated in FIG. 4B, the control unit 3 proceeds to step S23. In step S23, an e-mail in which a message indicating that an image change has been detected is inserted in the body is created. At the same time, the corresponding monitoring image data A immediately before the arrival of the main motion and the monitoring image data B immediately after the arrival of the main motion are read from the storage unit 4, and the difference between the monitoring image data A and B and the image processing unit 5 previously. The absolute difference image C calculated by the detection module 51 is attached to the electronic mail as an attached file. Then, the electronic mail is output to the communication unit 6 and transmitted to the management center CT.
Therefore, the person in charge of monitoring at the monitoring center CT knows the occurrence of the damage from the message in the e-mail body, and further determines the degree of the damage based on the attached monitoring image data A and B and the absolute difference image C. It becomes possible to grasp.

On the other hand, when no significant change is detected in the absolute difference image C as in the case illustrated in FIG. 4A, the control unit 3 indicates that no change in the image has been detected in the text. Create an email with the URL inserted. At the same time, the monitoring image data B immediately after reaching the corresponding main motion is read from the storage unit 4 and the monitoring image data B is attached to the e-mail as an attached file. Then, the electronic mail is output to the communication unit 6 and transmitted to the management center CT.
Therefore, the person in charge of monitoring work at the monitoring center CT can perform a visual inspection on the monitoring image data B immediately after the arrival of the main movement, thereby confirming whether there is an abnormality in the monitored facility just in case. It becomes.

  As described above, in this embodiment, an emergency earthquake warning is received by the receiver 7, and the camera 1 is operated during the period from when the earthquake early warning is received until the main motion of the earthquake arrives. The facility is imaged, and the monitoring image data A obtained thereby is stored in the storage unit 4. Subsequently, the presence or absence of the main motion of the earthquake is monitored based on the earthquake detection signal output from the earthquake sensor 8 installed in the vicinity of the monitored facility, and the camera is detected after the arrival of the main motion is detected. 1 is operated again to image the monitored facility, and the monitoring image data B obtained thereby is stored in the storage unit 4 in association with the monitoring image data A. Then, the absolute difference value C between the acquired monitoring image data A and B is calculated, the calculated absolute difference value C is compared with a preset threshold value d, and the comparison result is also obtained. In addition, it is determined whether or not the monitoring target facility is damaged, and the result is notified to the monitoring center CT by electronic mail.

  Therefore, the imaging operation of the monitoring target facility is performed only twice when the emergency earthquake warning is received and after the main motion arrives. For this reason, the monitoring image data is only the image data A and B obtained by the above two imaging operations. Therefore, the capacity of the storage unit 4 can be greatly reduced as compared with the case where the monitoring target facility is imaged constantly or frequently. In addition, since the monitoring image data of the monitoring target facility can always be acquired at the optimal timing before and after the arrival of the main motion, it is possible to always reliably determine the damage status of the monitoring target facility.

Prior to the imaging operation immediately before the arrival of the main motion, the estimated seismic intensity of the main motion (preliminary seismic intensity) is extracted from the emergency earthquake early warning, and the estimated seismic intensity is compared with a preset threshold value α. Only when the estimated seismic intensity is greater than or equal to the threshold value α, the camera 1 is caused to perform an imaging operation. Further, prior to the imaging operation immediately after the arrival of the main motion, the actual seismic intensity of the main motion is measured based on the detection signal of the seismic sensor 8, and this measured seismic intensity is compared with the threshold value β. Only when the measured seismic intensity is equal to or greater than the threshold value β, the camera 1 is caused to perform an imaging operation.
Therefore, the imaging operation by the camera 1 is performed only when there is a possibility that the monitoring and handling facility may be damaged, and this makes it possible to reduce power consumption by reducing substantially unnecessary imaging operations, Further, unnecessary image data can be prevented from being stored in the storage unit 4.

  Further, when calculating the absolute difference value between the monitoring image data A and the monitoring image data B, prior to that, in order to equalize the brightness of the monitoring image data A and B, the monitoring image data A and B are imaged. A density standardization process is performed. For this reason, even if the brightness of the image differs between the monitoring image data A and B due to sudden changes in sunshine conditions such as the weather or the occurrence of a fire, the difference in brightness is corrected by image density normalization processing. After that, an absolute difference value can be obtained, which makes it possible to perform monitoring at a low cost and with high accuracy by eliminating the influence of sunlight and fire on the image.

  Further, the brightness correction process, the difference calculation process, and the comparison determination process are performed for each pixel of the image data. For this reason, it is possible to perform appropriate illuminance correction over the entire area of the image data, and thereby it is possible to accurately determine the change over the entire monitoring object.

  In addition, the change in the brightness of the image data due to the change in the sunshine conditions is corrected for each of the R, G, and B pixel elements, and the change in the image is considered in consideration of the brightness of each of the R, G, and B pixel elements. Presence / absence is determined. As a result, even when a color image is used, it is possible to make an optimal determination in consideration of changes in sunshine conditions.

  The present invention is not limited to the above embodiment. For example, the residual determination module 52 is provided with an expansion filtering processing function, and the expansion processing for expanding the boundary of the region where the difference value exists with the filtering processing function with respect to the absolute difference image obtained by the difference detection module 51 And the difference information after the expansion filtering process may be compared with a threshold value. In this way, the boundary region of the image change region appearing in the absolute difference image is enlarged, and it becomes possible to detect as a clearer change.

  Further, the residual determination module 52 has a contraction filtering processing function, and the contraction for reducing the boundary of the region where the difference value exists by the filtering processing function with respect to the absolute difference image obtained by the difference detection module 51. Processing may be performed, and the difference information after the contraction filtering processing may be compared with a threshold value. In this way, the boundary region of the image change that appears in the absolute difference image is reduced, thereby eliminating the minute image change that can be regarded as noise and detecting only the true image change. .

  Furthermore, when the monitoring image data A and B are imaged, it is assumed that the camera 1 is oscillating due to the influence of the earthquake P wave and S wave. Therefore, it is preferable to take measures against the shaking in the control unit 3, the camera 1, and the image processing unit 5. For example, the control unit 3 monitors whether or not the main motion has converged based on the detection signal of the earthquake sensor 8 and confirms that the main motion has converged, and then operates the camera 1 to obtain monitoring image data B. It is an effective measure against the above-mentioned shaking. In addition, when the camera is installed on a monitoring tower or the like, it may be possible that the monitoring tower continues to sway even after the main movement converges. After monitoring the shaking and confirming that the main motion has converged and further confirming that the shaking of the detection camera 1 has stopped, the camera 1 may be operated to obtain the monitoring image data B. Further, the camera 1 itself is provided with a blur correction function, the camera 1 is installed in a monitoring tower or the like via a vibration control mechanism, and the image processing unit 5 performs correction to eliminate the blur component of the image by image processing. Of course, it is also effective.

In addition, the configuration of the apparatus, the monitoring control procedure and control contents, the contents of image processing, and the like can be variously modified and implemented without departing from the gist of the present invention.
In short, the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

It is a schematic block diagram of the monitoring system using the facility damage monitoring apparatus concerning this invention. It is a block block diagram which shows one Embodiment of the facility damage monitoring apparatus concerning this invention. It is a flowchart which shows the monitoring control procedure and control content by the facility damage monitoring apparatus shown in FIG. It is a figure which shows an example of the image processing operation | movement by the facility damage monitoring apparatus shown in FIG.

Explanation of symbols

  DS1 to DSn ... Facility damage monitoring device, CT ... Management center, NW ... Communication network, 1 ... Camera, 2 ... Camera interface (camera I / F), 3 ... Control unit, 4 ... Storage unit, 5 ... Image processing unit, DESCRIPTION OF SYMBOLS 6 ... Communication unit, 7 ... Receiver, 8 ... Earthquake sensor, 31 ... Rapid report analysis module, 32 ... Damage determination module, 33 ... Camera control module, 34 ... Communication control module, 51 ... Difference detection module, 52 ... Residual determination module.

Claims (12)

A camera fixedly installed at a position where the facility to be monitored can be imaged;
A receiver for receiving earthquake early warnings;
In the period from the time when the earthquake early warning is received by the receiver to the time when the main motion of the earthquake arrives, the camera is operated in a timed manner to capture the monitored facility, and the first image data is acquired. First imaging control means for storing;
Main motion detection means for receiving an earthquake detection signal from an earthquake sensor installed in the vicinity of the monitored facility, and detecting the presence or absence of the main motion based on the earthquake detection signal;
After the arrival of the main movement is detected, the camera is operated again in a timely manner to image the monitored facility, and second imaging control means for acquiring and storing second image data;
Difference calculating means for calculating difference information between the acquired first and second image data;
Comparing the calculated difference information with a preset threshold value, and determining means for determining whether there is a change in the monitored facility based on the comparison result, facility damage monitoring apparatus.   The first imaging control means estimates the seismic intensity of the main motion from the contents of the received earthquake early warning, and when the estimated value of the seismic intensity is equal to or greater than a preset first threshold, the camera is timed. The facility damage monitoring apparatus according to claim 1, wherein the facility to be monitored is operated to image the monitoring target facility. The main motion detection means has a function of measuring an actual seismic intensity of the main motion based on an earthquake detection signal output from the earthquake sensor,
In the second imaging control means, the estimated value of the seismic intensity is determined to be greater than or equal to a first threshold value by the first imaging control means, and the measured value of the seismic intensity of the main motion by the main motion detecting means is the first value. 3. The facility damage monitoring apparatus according to claim 2, wherein when the threshold value is equal to or greater than 2, the camera is operated again in a timely manner to capture an image of the monitored facility. The difference calculating means includes
Image processing means for performing normalization processing of image density on the first and second image data in order to equalize the brightness of the first image data and the second image data;
The facility damage monitoring apparatus according to claim 1, further comprising means for calculating difference information between the first and second image data after the image density normalization processing. The image processing means includes
Means for calculating an average value of image density of each pixel or pixel block of the first image data;
Means for calculating an average value of image density of each pixel or pixel block of the second image data;
Based on the calculated average value of the image density of the first image data and the calculated average value of the image density of the second image data, in order to make these average values arbitrary common values, 5. The facility damage monitoring apparatus according to claim 4, further comprising means for performing image density correction processing for each pixel or pixel block of the first and second image data. The image processing means performs the image density normalization processing for each of R, G, and B pixel elements,
The means for calculating the difference information obtains difference information between the first and second image data for each of the R, G, and B pixel elements,
The determination means compares the calculated difference information with a threshold value for each of the R, G, and B pixel elements, and when any one or more of each pixel element is equal to or more than the threshold value. The facility damage monitoring apparatus according to claim 4, wherein it is determined that the monitoring target facility has changed.   When it is determined by the determination means that the monitored facility has changed, the corresponding first and second image data and the difference information calculated by the difference calculation means are preset as notification destinations. The facility damage monitoring apparatus according to claim 1, further comprising means for transmitting to a terminal device of a manager in charge via a communication network. The process of receiving an earthquake early warning,
In the period from the time when the earthquake early warning is received until the main motion of the earthquake arrives, the camera is operated in a timed manner to image the monitored facility, and the first image data is acquired and stored;
Receiving an earthquake detection signal from an earthquake sensor installed in the vicinity of the facility to be monitored, and detecting the presence or absence of the main motion based on the earthquake detection signal;
After the arrival of the main motion is detected, the process of operating the camera again in a timed manner to image the monitored facility, and acquiring and storing second image data;
Calculating difference information between the acquired first and second image data;
A facility damage monitoring method comprising: comparing the calculated difference information with a preset threshold value and determining whether or not the monitoring target facility has changed based on the comparison result. .   In the process of acquiring and storing the first image data, the seismic intensity of the main motion is estimated from the content of the received earthquake early warning, and the estimated value of the seismic intensity is equal to or greater than a preset first threshold value. The facility damage monitoring method according to claim 8, wherein the facility is operated for a limited time to image the monitored facility. The process of detecting the presence or absence of the arrival of the main movement is to measure the actual seismic intensity of the main movement based on the earthquake detection signal output from the earthquake sensor,
In the process of acquiring and storing the second image data, the estimated value of the seismic intensity of the main motion is determined to be greater than or equal to a first threshold value, and the measured value of the seismic intensity of the main motion is a second threshold value. The facility damage monitoring method according to claim 9, wherein in the above case, the camera is operated again in a timely manner to image the monitored facility. The process of calculating the difference information includes:
Performing a process of normalizing image density on the first and second image data in order to equalize the brightness of the first image data and the second image data;
The facility damage monitoring method according to claim 8, further comprising a step of calculating difference information between the first and second image data after the image density normalization processing.   When it is determined that there is a change in the monitored facility in the process of determining whether there is a change in the monitored facility, the corresponding first and second image data and the difference calculated by the difference calculation means 9. The facility damage monitoring method according to claim 8, further comprising a step of transmitting information via a communication network to a terminal device of a manager in charge set in advance as a notification destination.

Images