JP2019021041A - Monitoring camera system - Google Patents

Abstract

To detect mask scheming performed on a monitoring camera using a material exerting semi-permeability or absorbency.SOLUTION: A monitoring camera system 1 includes an imaging unit 2, a proximity sensor 6 that includes a light emitter which emits infrared light and a light receiver which receives infrared radiation and is disposed near the imaging unit 2, scheming abnormality determination means 26 that, when a first criterion that an output of the proximity sensor 6 is equal to or larger than a first predetermined threshold is satisfied, determines that the imaging unit 2 suffers scheming abnormality of interfering a viewing field, and a color sensor 4 that is color change detection means which is disposed near the imaging unit 2 and detects a degree of change in colors of ambient light. If a second criterion that an output of the proximity sensor 6 is equal to or larger than a second predetermined threshold smaller than the first threshold and that the degree of change in colors is equal to or larger than a predetermined color change threshold is satisfied, the scheming abnormality determination means 26 determines that the imaging unit suffers scheming abnormality.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a surveillance camera device, and more particularly, to a surveillance camera device having a function of detecting a plan that obstructs the field of view of a camera.

  2. Description of the Related Art Conventionally, there is a system for monitoring a suspicious person intrusion into a monitoring target space such as a store or a house using a monitoring camera. For a surveillance camera, a malicious person performs a so-called visual field obstruction, masking plan action, etc., such as covering the lens surface of the surveillance camera with something, applying tape, spraying spray paint, etc. The surveillance camera may be invalidated. Therefore, various devices have been made for the purpose of detecting an abnormal state due to the plan action. In the following Patent Document 1, a proximity sensor including a light projecting / receiving unit is provided in the vicinity of an imaging unit of a surveillance camera, the projector projects light in front of the camera, a proximity object is detected based on reflected light with respect to the light, and a plan action for the surveillance camera Is described. Japanese Patent Application Laid-Open Publication No. 2003-259259 describes that a scheme action is detected based on luminance dispersion in an image with respect to a scheme that gives a blurred image.

JP 2003-87610 A JP 2010-176411 A

  When the material used for the mask plan has a semi-transmitting property or a light-absorbing property, in the monitoring camera having the above-described proximity sensor, there is a possibility that reflected light from the mask member with respect to light projection is reduced. If the threshold of the intensity of the reflected light that determines the presence or absence of a proximity object is lowered in order to detect such a mask measure, the false alarm of the mask measure increases. On the other hand, in a surveillance camera that detects a plan action based on the above-described image, a configuration of an arithmetic unit or the like that performs relatively complicated image processing in real time is required, which may increase costs.

  The present invention has been made in view of the above problems, and provides a surveillance camera device capable of preferably detecting a mask image even if an object close to the camera has translucency or light absorption.

  (1) A monitoring camera device according to the present invention includes an imaging unit, a color change detection unit that is installed in the vicinity of the imaging unit and detects a degree of change in the color of ambient light, and a plan abnormality that disturbs the visual field of the imaging unit. A plan abnormality determination unit that determines the plan abnormality based on the fact that the color change degree is equal to or greater than a predetermined color change threshold value.

  (2) Another surveillance camera device according to the present invention includes an imaging unit, a light emitting unit that emits infrared light, and a light receiving unit that receives infrared light, and a proximity sensor disposed in the vicinity of the imaging unit, and the proximity A plan abnormality determining unit that determines that the sensor output is equal to or greater than a predetermined first threshold as a first determination criterion, and that is based on satisfying the determination criterion; A color change detecting unit that is installed in the vicinity of the imaging unit and detects a color change degree of the ambient light, and the plan abnormality determination unit has a predetermined output lower than the first threshold value. The second determination criterion is that the color change degree is equal to or greater than a second threshold value and the color change degree is equal to or greater than a predetermined color change threshold value.

  (3) In the surveillance camera device described in the above (1) or (2), the color change detection means can calculate the degree of color change based on the output of the color sensor.

  (4) In the surveillance camera device described in (3) above, the proximity sensor and the color sensor can be formed as a sensor element formed integrally.

  According to the present invention, it is possible to preferably detect the mask image even if the proximity object of the monitoring camera has a semi-transmitting property or a light absorbing property.

It is a schematic diagram which shows the structure of the outline of the surveillance camera apparatus which concerns on embodiment of this invention. It is a flowchart explaining the operation | movement of the outline of the surveillance camera apparatus which concerns on embodiment of this invention. It is a general | schematic flowchart of the update process of the reference value of the output of a proximity sensor by a reference value acquisition means. It is a general | schematic flowchart of the color change determination process by a color change degree determination means. It is a general | schematic flowchart of the plan abnormality determination process by a plan abnormality determination means.

  Hereinafter, embodiments of the present invention (hereinafter referred to as embodiments) will be described with reference to the drawings.

  FIG. 1 is a schematic diagram illustrating a schematic configuration of a monitoring camera device 1 according to the embodiment. The monitoring camera device 1 includes an imaging unit 2, a color sensor 4, a proximity sensor 6, a control unit 8, a communication unit 10, and a storage unit 12.

  The monitoring camera device 1 basically operates as a color camera, and monitors the occurrence of abnormalities such as intrusion and danger of people into the monitoring target space. An image captured by the imaging unit 2 can be transmitted to the monitoring center (not shown) by the communication unit 10 via a communication line or the like. For example, the transmitted image is used by a monitoring center to confirm the occurrence of an abnormality at a monitoring center. Further, an image photographed by the imaging unit 2 can be recorded in the storage unit 12. For example, the recorded image is transmitted in response to a request from the monitoring center. Moreover, the monitoring camera apparatus 1 notifies a monitoring center by the communication part 10, when a plan abnormality is detected.

  The imaging unit 2 includes an optical system such as a lens and an imaging element such as a CCD image sensor or a CMOS image sensor. The imaging unit 2 also includes a gain control amplifier circuit (automatic gain control: AGC) that automatically controls the gain of the camera, and an AD conversion unit that converts an analog signal into a digital signal. Further, the imaging unit 2 includes an image signal processing unit configured by a digital signal processor (DSP) or the like, and image data obtained by performing predetermined image processing such as gamma processing in the image signal processing unit. Output to the control unit 8.

  The color sensor 4 is installed in the vicinity of the imaging unit 2 and measures and outputs the intensity of a plurality of color components of ambient light. For example, the color sensor 4 is a sensor element in which three light receiving units having sensitivity to red (R), green (G), and blue (B) light are integrally formed. A light receiving portion of a certain color in the color sensor 4 can be constituted by a color filter and a photodiode that selectively transmit light of the color. The color sensor 4 measures the RGB components of the ambient light using the RGB light receiving unit, and can detect the color of the ambient light according to, for example, the RGB ratio. In the present embodiment, the color change detection unit detects the degree of change in the color of the ambient light based on the output of the color sensor 4. However, the color change detection means is not limited to this.

  The proximity sensor 6 includes a photodiode having sensitivity only in the infrared light region as a light receiving unit, and includes a light emitting diode (LED) that emits infrared light as a light emitting unit. The proximity sensor 6 alternately and periodically measures the amount of light incident on the photodiode when the LED is not emitting light and the amount of light incident on the photodiode when the LED is emitting light, and a value obtained by integrating the difference value over a predetermined period. Is output. For example, when there is a proximity object, reflected light from the proximity object with respect to the LED light is received by the photodiode, and therefore the presence or absence of the proximity object can be detected based on the magnitude of the photodiode output. In the present embodiment, the monitoring camera device 1 includes a plurality of proximity sensors 6, which detect proximity objects at a plurality of locations near the imaging unit 2. In the present embodiment, an example in which four proximity sensors 6-1 to 6-4 are provided will be described. It is also possible to adopt a configuration in which only one proximity sensor 6 is provided.

  The color sensor 4 and the proximity sensor 6 can be a single sensor element integrally formed in a small package. By using a color / proximity sensor in which the color sensor 4 and the proximity sensor 6 are integrated, the surveillance camera device 1 can be reduced in size and cost. For example, using a color / proximity sensor having a plurality of proximity sensors 6-1 to 6-4 as one package, each of a plurality of locations in the vicinity of the imaging unit 2 that detects a proximity object, and the proximity sensor 6 corresponding to the location. It can be set as the structure couple | bonded between these with the optical conduit.

  The control unit 8 is configured using a microprocessor (MPU) or the like, and performs various operations according to a program to be executed. For example, the control unit 8 functions as the reference value acquisition unit 20, the saturation determination unit 22, the color change degree determination unit 24, and the plan abnormality determination unit 26.

  The reference value acquisition unit 20 sets / updates a reference value for proximity abnormality determination at a predetermined timing. Specifically, the reference value acquisition unit 20 sets the reference value based on the output of the proximity sensor 6 during a period when the visual field is not obstructed when the operation of the monitoring camera device 1 is started. For example, in the initial setting of the reference value, it can be assumed that the visual field disturbance does not occur unless the output of the proximity sensor 6 is saturated. It is also possible to perform initial setting of the reference value after confirming that the user has not disturbed the visual field with respect to the imaging unit 2. Further, the reference value acquisition unit 20 has a function as a reference value update unit that updates the reference value in accordance with the time change of the environment. This process will be further described later.

  The saturation determination means 22 determines that the predetermined amount or more of light is received by the proximity sensor 6 and its output is in a saturated state.

  Based on the outputs of the color sensor 4 and the proximity sensor 6, the plan abnormality determination unit 26 determines a plan abnormality that disturbs the field of view of the imaging unit 2.

  The communication unit 10 transmits the image captured by the imaging unit 2 to a remote monitoring center or the like connected via a communication line. In addition, when an abnormality in the plan is detected, an abnormality alarm is transmitted to the monitoring center or the like.

  The storage unit 12 stores various information such as programs used in the control unit 8, data such as reference values, and identification information of the monitoring camera. In addition, the storage unit 12 stores an image captured by the imaging unit 2. The image storage capacity can be set within a preset upper limit, and when the accumulated image capacity reaches the upper limit, old images can be sequentially deleted to store new images.

  FIG. 2 is a flowchart for explaining the schematic operation of the monitoring camera device 1.

  The control unit 8 acquires measurement values of the color sensor 4 and the proximity sensor 6 (step S001). Specifically, the control unit 8 acquires the intensity values of the RGB color components from the register of the color sensor 4 at predetermined time intervals. Further, the control unit 8 calculates the integral value of the difference between the light receiving unit outputs in the non-light emitting state and the light emitting state of the light emitting unit of the proximity sensor 6 at a predetermined time interval from each of the proximity sensors 6-1 to 6-4. Get as output of.

  The saturation determination means 22 determines whether or not the output of the proximity sensor 6 is in a saturated state (step S002). For example, a saturation flag is provided for each proximity sensor 6, and the saturation determination unit 22 determines whether the light receiving unit output in the light emitting state of the light emitting unit is the specification of the proximity sensor 6 for any of the four proximity sensors 6-1 to 6-4. When the upper limit value given by the above is reached, it is determined that the proximity sensor 6 is in a saturated state, and the saturation flag of the proximity sensor 6 is set to an on state.

  When there is no saturation flag set to ON in the saturation determination S002 (in the case of “No” in step S003), initialization processing of values of various parameters including the reference value of the proximity sensor 6 is performed (step S004). ). On the other hand, if there is a saturation flag in the on state (“Yes” in step S003), if the initialization is performed in the saturation state, an abnormal value can be set as the reference value of the proximity sensor 6 or the like. Therefore, the process returns to step S001, and the processes of steps S001 to S003 are repeated until the saturated state is resolved.

  In the initialization process S004, the reference value acquisition unit 20 performs initial setting of the reference value of the output of the proximity sensor 6. The reference value is the total value of the outputs of the plurality of proximity sensors 6-1 to 6-4 when there is no plan abnormality. This reference value is a value for removing fluctuations in the output of the entire proximity sensor 6 when judging the proximity abnormality, and it is possible to suppress false alarms by removing the fluctuations. In the configuration in which only one proximity sensor 6 is provided, the reference value is given by the output of one proximity sensor 6.

  As described above, the output of each proximity sensor 6 is obtained as a value obtained by integrating the difference value of the amount of infrared light received by the light receiving unit between when the light emitting unit emits light and when it does not emit light over a predetermined time. The outputs are summed to obtain the total value of the outputs of the plurality of proximity sensors 6.

  The reference value acquisition unit 20 can calculate a reference value related to the output of the proximity sensor 6 based on a single output of the proximity sensor 6, but in this embodiment, it is determined that the plan is abnormal as the reference value. The average value of the output over a period of no time is calculated. By using the average value, it can be made less susceptible to temporary noise and the like.

  Specifically, when it is confirmed in step S003 that the saturation flags of all the proximity sensors 6 are in the OFF state, the control unit 8 determines that the plan abnormality has not occurred, and the control unit 8 indicates the plan abnormality flag indicating the presence / absence of the plan abnormality. Set to the off state. Then, the reference value acquisition means 20 calculates the average value of the total value of the above outputs based on the output of the proximity sensor 6 obtained periodically and repeatedly within a predetermined period, and sets it as the reference value.

  Further, the reference value acquisition unit 20 acquires an initial value for an offset value related to the output of each proximity sensor 6. The offset value of the proximity sensor 6 is basically given by the output of the proximity sensor 6 when no proximity object exists. The output is an integral value of the difference between the light receiving unit output in the light emitting state and the light receiving unit output in the non-light emitting state of the light emitting unit as described above. For example, there may be a difference in the transmission efficiency of the optical conduit for each proximity sensor 6, and the offset value is set for each proximity sensor 6 in order to correct and remove the influence of the difference. In the present embodiment, in order to reduce the influence of output variations, the output of the proximity sensor 6 is repeatedly acquired within a predetermined period, the average value thereof is calculated, and this is used as the offset value. In the initialization process S004, an average value in a predetermined period before the operation of the monitoring camera device 1 is started is obtained as an initial value of the offset value.

  In addition, in the initialization process S004, the control unit 8 sets, for example, the proximity abnormality determination count used for the plan abnormality determination to 0, which is an initial value, and stores the current value as the output value of the color sensor 4 used for color change determination. To do. In addition, various state values used in processing to be described later are also set to initial values. For example, the color sensor variation flag is set to an off state.

  After the initialization process S004, the monitoring camera device 1 performs image monitoring of the monitoring target space while detecting a plan abnormality. During the image monitoring, the control unit 8 performs a process of updating the reference value of the output of the proximity sensor 6 by the reference value acquisition means 20 (step S005). Similarly to step S001, the control unit 8 performs the process of updating the color sensor 4 and the proximity sensor 6. A measured value is acquired (step S006).

  The control unit 8 determines whether or not the proximity sensor 6 is saturated by the saturation determination unit 22 (step S007). This determination is performed in the same manner as in step S002. If any of the proximity sensors 6 is saturated, the saturation flag of the proximity sensor 6 is set to an on state.

  When the saturation flag is not turned on (in the case of “No” in step S008), the control unit 8 performs a color change determination process by the color change degree determination unit 24 (step S009), and then determines the plan abnormality. A plan abnormality determination process is performed by means 26 (step S010). When the plan abnormality flag is maintained in the off state in the plan abnormality determination process S010 (in the case of “No” in step S011), the control unit 8 returns the process to step S005, and after the initialization process S004. Repeat the process.

  On the other hand, when the plan abnormality flag is set to ON (in the case of “Yes” in step S011), the control unit 8 transmits an abnormality report to the monitoring center or the like via the communication unit 10, and the plan abnormality is detected. This is notified externally (step S012). In this case, the control unit 8 waits for the elapse of a predetermined time set in consideration of the time required for coping / response of the monitoring center or the like (step S013), and then returns to step S001 to include the initialization process S004. Repeat the process.

  If the saturation flag is on (“Yes” in step S008), the control unit 8 returns to step S006. That is, since there is a possibility that the reference value of the proximity sensor 6 is not set appropriately in the saturated state, the processing of steps S006 to S008 is basically repeated until the saturated state is eliminated without performing the reference value update processing S005. .

  FIG. 3 is a schematic flowchart of the reference value update process (step S005 in FIG. 2) of the output of the proximity sensor 6 by the reference value acquisition means 20.

  Based on the output obtained from the proximity sensor 6 at predetermined time intervals, the reference value acquisition unit 20 sequentially stores and accumulates data used for calculating the reference value in a buffer memory of a predetermined size prepared for reference value update processing. . When the amount of accumulated data reaches the upper limit of the capacity of the buffer memory, the old data is erased in order and new data is stored.

  Specifically, in the reference value update process S005, when a new output value is obtained from the proximity sensor 6, data based on the output value is added to the buffer memory (step S101), and the reference value update count is incremented (step S102). . Here, the data stored in the buffer memory includes output values of the four proximity sensors 6 and their total values. The reference value update counter is initially set to 0 when the monitoring camera device 1 is started, for example.

  While the reference value update count is less than the predetermined update threshold, the update of the reference value is suspended, and the process proceeds to step S006 in FIG. 2 (in the case of “No” in step S103). Here, the update threshold can be set by the user based on a desired time interval for updating the reference value.

  If the reference value update count reaches the update threshold value (in the case of “Yes” in step S103), if the reference value update flag is on (in the case of “Yes” in step S104), the reference value is It is updated (step S105). Here, the reference value update flag is for suppressing the update of the reference value when there is a possibility that the plan abnormality has occurred. When the flag is in the off state (in step S104, “ In the case of “No”, the reference value update processing S105 is not performed.

  In the reference value update processing S105, the reference value of the output of the proximity sensor 6 and the offset value of the output of each proximity sensor 6 are updated. As described in the initialization process S004, the reference value of the entire proximity sensor 6 is a reference value related to the total output of the plurality of proximity sensors 6-1 to 6-4 in the present embodiment. In the update process S105, the reference value update flag is in an on state, and the proximity sensor 6 can obtain an output in a state in which there is no plan abnormality. Therefore, in the update process S105, the reference value acquisition unit 20 obtains an average value of the total output of the proximity sensor 6 during a period when the plan is not abnormal, and updates the reference value of the output of the proximity sensor 6 with the average value. In the present embodiment, as described above, the output of the proximity sensor 6 is obtained as an integral value within a predetermined time of a difference value obtained by subtracting the infrared light reception amount during non-light emission from the infrared light reception amount during light emission of the light emitting unit. Therefore, the total output of the proximity sensors 6 is obtained by the sum of the output values of the proximity sensors 6.

  Further, the reference value acquisition means 20 obtains and updates the offset value of the output of the proximity sensor 6 in the same manner as in the initialization process S004.

  As described above, if the reference value update flag is on, the update process S105 is executed. If the reference value update flag is off, the update process S105 is not executed, but in any case, the reference value update count is cleared (step S106). ). That is, when the reference value update count reaches the update threshold value (in the case of “Yes” in step S103), the reference value acquisition unit 20 updates the reference value regardless of whether or not the reference value update process S105 is executed. The count is reset to 0, and the process proceeds to step S006 in FIG.

  FIG. 4 is a schematic flowchart of the color change determination process (step S009 of FIG. 2) by the color change degree determination means 24. The color change degree determination means 24 acquires the current output of the color sensor 4 (step S201). Specifically, the intensity values of the RGB components detected by the color sensor 4 are acquired.

  Based on the current output of the color sensor 4 acquired in step S201 and the output of the color sensor 4 in the previous process, the color change degree determination unit 24 evaluates the change in the output of the color sensor 4, and the change is detected. If it is equal to or greater than the predetermined threshold (if “Yes” in step S202), the color sensor variation flag is set to the on state (step S203). For example, if the difference between the current value and the previous value is greater than or equal to a threshold value for any of the RGB component values, the color change degree determination unit 24 can determine that the output variation of the color sensor 4 is equal to or greater than the threshold value. The color change degree determination means 24 converts RGB values into coordinate values of other color systems using hue, saturation, brightness, etc., and outputs the output of the color sensor 4 based on the change amount of the coordinate values. Variations can also be judged.

  On the other hand, if the variation in the output of the color sensor 4 is less than the threshold (“No” in step S202), step S203 is skipped and the color sensor variation flag is kept in the off state set in the initialization process S004. Be drunk.

  When the color change determination unit 24 performs the above-described processing, the current output data of the color sensor 4 is stored as output data of the color sensor 4 at the previous processing for the next processing (step S204), and then FIG. The process proceeds to step S010. In the output variation evaluation process S202 in the first color change determination process S009, the color change degree determination unit 24 uses the data stored in the initialization process S004 as the output data of the previous color sensor 4.

  FIG. 5 is a schematic flowchart of the plan abnormality determination process (step S010 in FIG. 2) by the plan abnormality determination means 26. The plan abnormality determination unit 26 sets the first determination criterion that the output of the proximity sensor 6 is equal to or greater than a predetermined first threshold value. For example, the first determination criterion can be satisfied when the material that blocks the visual field of the imaging unit 2 is a substance that sufficiently reflects infrared light emitted from the proximity sensor 6. In addition, the plan abnormality determination unit 26 determines whether the output of the proximity sensor 6 is equal to or higher than a predetermined second threshold lower than the first threshold and the color change degree is equal to or higher than a predetermined color change threshold. The standard. For example, when the material that blocks the visual field of the imaging unit 2 is semi-transmissive or light-absorbing with respect to the infrared light emitted from the proximity sensor 6, the first determination criterion may not be satisfied. The second criterion is for detecting a mask plan in such a case.

  First, the plan abnormality determination unit 26 determines whether or not the output of the proximity sensor 6 satisfies the first determination criterion (step S301). In the present embodiment, the plan abnormality determination unit 26 calculates the total value of the outputs of the proximity sensors 6-1 to 6-4, and determines whether or not the total value satisfies the first determination criterion. At this time, in this embodiment, the reference value of the entire proximity sensor 6 obtained in step S105 can be taken into account. For example, the difference between the total value of the outputs of the proximity sensors 6-1 to 6-4 and the reference value. Is compared with the first threshold value.

  When the first determination criterion is satisfied (in the case of “Yes” in step S301), there is a possibility that the visual field is disturbed with respect to the imaging unit 2, and there is a possibility that a plan abnormality may occur. it can.

  On the other hand, when the first determination criterion is not satisfied (“No” in step S302), the plan abnormality determination unit 26 checks whether the second determination criterion is satisfied. In other words, the plan abnormality determination means 26 relates to the second determination criterion that the color sensor fluctuation flag is in the ON state (step S302), and the output of the proximity sensor 6 is equal to or higher than a predetermined second threshold lower than the first threshold. If both conditions are satisfied (in the case of “Yes” in steps S302 and S303), it is assumed that the second determination criterion is satisfied. In this case as well, there is a possibility that the visual field is disturbed with respect to the imaging unit 2, and it is possible to set a state where there is a possibility that an abnormality in the plan has occurred. Note that the output of the proximity sensor 6 in step S303 is defined in the same manner as in step S301 described above.

  The plan abnormality determination unit 26 satisfies the case where the first determination criterion is satisfied (in the case of “Yes” in step S301) and the case where the second determination criterion is satisfied (in the case of “Yes” in steps S302 and S303). Immediately, it is not determined to be a plan abnormality, but is temporarily treated as a state in which the proximity sensor 6 has detected an abnormality (proximity abnormality state), and is determined to be a plan abnormality when the proximity abnormality state continues for a predetermined period. The proximity abnormality determination number is used to measure the duration of the proximity abnormality state, and the plan abnormality determination unit 26 increments the proximity abnormality determination number when the first or second determination criterion is satisfied (step S304). .

  The plan abnormality determination unit 26 sets the reference value update flag to an off state when the proximity abnormality determination count is equal to or greater than the predetermined number (plan abnormality pre-threshold) (“Yes” in step S305) (step S306). . Thereby, the reference value update process (S105 in FIG. 2) during the proximity abnormality detection is suppressed. The plan abnormality pre-threshold value can be set to 1, for example.

  Further, when the proximity abnormality determination count is equal to or greater than the plan abnormality threshold value (in the case of “Yes” in step S307), the plan abnormality determination unit 26 sets the plan abnormality flag to the on state (step S308), and the processing is performed. Proceed to step S011 of step 2.

  On the other hand, when neither the first determination criterion nor the second determination criterion is satisfied (in the case of “No” in step S302 or S303), the plan abnormality determination unit 26 resets the proximity abnormality determination number to 0 (step If the color sensor variation flag is on (S309), it is reset to off (step S310), and the process proceeds to step S011 in FIG. Incidentally, in this case, the plan abnormality flag is kept in the initially set off state.

  When the proximity abnormality determination count is less than the plan abnormality pre-threshold (in the case of “No” in step S305), the plan abnormality determination unit 26 performs the process while maintaining the reference value update flag in the initially set on state. Proceed to step S011 of FIG. Incidentally, in this case, the plan abnormality flag is in an off state that is initially set.

  When the number of proximity abnormality determinations is less than the plan abnormality threshold (in the case of “No” in step S307), the plan abnormality determination unit 26 performs the processing while maintaining the plan abnormality flag in the initially set off state. The process proceeds to step S011. Incidentally, in this case, the reference value update flag is set to OFF in step S306.

  Here, in the present embodiment including a plurality of proximity sensors 6, the number of sensors having outputs equal to or higher than the third threshold set lower than the first threshold among the plurality of proximity sensors 6 is a predetermined plurality or more. As a third criterion, if the first and third criteria are satisfied instead of the first criterion, the plan abnormality may occur, and the second criterion is Thus, a configuration in which the second and third determination criteria are satisfied may be in a state where there is a possibility that a plan abnormality has occurred.

  An event in which the entire output of the proximity sensor 6 in step S301 or S303 is equal to or greater than the threshold value may occur even when a part of the field of view of the imaging unit 2 is blocked by insects, raindrops, or the like. In this regard, if the output of the proximity sensor 6 increases at a plurality of locations in the vicinity of the imaging unit 2, if it is detected, it is presumed that the wide field of view is obstructed and eliminates false alarm events related to plotting such as insects and raindrops. Is possible. The third criterion is a criterion from this viewpoint. For example, in the present embodiment, the number of proximity sensors 6 having an output equal to or greater than the third threshold is four. That is, the third criterion can be that all four proximity sensors 6 have an output equal to or greater than the third threshold value.

  Further, when the output of the proximity sensor 6 is compared with the second threshold value in the third determination criterion, in the present embodiment, the offset value of the output of the proximity sensor 6 obtained in step S105 is considered. Specifically, the result of subtracting the offset value of the proximity sensor 6 from the output of the proximity sensor 6 is compared with a preset third threshold value. Note that the third threshold value can be set for each proximity sensor 6 in consideration of the fact that there is a deviation in output among the plurality of proximity sensors 6, but the offset value for each proximity sensor 6 is set as in this embodiment. When the subtracted output is used, the third threshold value can be shared by the plurality of proximity sensors 6.

  Note that, in steps S301 and S303, the output of the proximity sensor 6 is the total of the proximity sensors 6-1 to 6-4. However, in a configuration in which only one proximity sensor 6 is provided, steps S301 and S303 are the one proximity sensor. The determination is made based on the output of the sensor 6.

  As described above, the surveillance camera device 1 can detect the presence or absence of the material even when the field of view of the imaging unit 2 is blocked by a material that transmits or absorbs part of the intensity of infrared light emitted from the proximity sensor 6. By detecting a change in the color of the image of the imaging unit 2 that may occur with the color sensor 4, it is possible to detect a mask image act appropriately.

  In the present embodiment, the proximity sensor 6 transmits and receives infrared light. However, the proximity sensor 6 may detect and detect a proximity object by transmitting and receiving sound waves (including ultrasonic waves), microwaves, and millimeter waves. .

  Further, the surveillance camera device 1 may be configured such that the proximity sensor 6 is omitted. That is, only the color sensor 4 is used among the color sensor 4 and the proximity sensor 6 in the above-described embodiment, and the plan abnormality determination unit 26 determines the degree of color change in the image of the imaging unit 2 based on the output of the color sensor 4. A configuration in which an abnormality in which a mask plan action is performed can be determined based on being above a predetermined color change threshold.

  DESCRIPTION OF SYMBOLS 1 Surveillance camera apparatus, 2 Image pick-up part, 4 Color sensor, 6 Proximity sensor, 8 Control part, 10 Communication part, 12 Memory | storage part, 20 Reference value acquisition means, 22 Saturation determination means, 24 Color change degree determination means, 26 Plan abnormality Judgment means.

Claims (4)

An imaging unit;
Color change detection means installed in the vicinity of the imaging unit for detecting the degree of change in the color of ambient light;
A plan abnormality determining means for determining a plan abnormality that obstructs the field of view of the imaging unit;
The plan abnormality determination means includes
Determining that the color scheme is abnormal based on the degree of color change being equal to or greater than a predetermined color change threshold;
A surveillance camera device characterized by the above. An imaging unit;
A proximity sensor disposed in the vicinity of the imaging unit, comprising a light emitting unit that emits infrared light and a light receiving unit that receives infrared light;
A plan abnormality determination that determines that the output of the proximity sensor is greater than or equal to a predetermined first threshold as a first determination criterion, and that it is a scheme abnormality that obstructs the imaging unit based on satisfying the determination criterion. Means,
Color change detection means installed in the vicinity of the imaging unit and detecting the degree of change in color of ambient light,
The plan abnormality determination means includes
The output of the proximity sensor is equal to or higher than a predetermined second threshold lower than the first threshold and the degree of color change is equal to or higher than a predetermined color change threshold. Determining that the plan is abnormal also by satisfying,
A surveillance camera device characterized by the above.   The monitoring camera device according to claim 1, wherein the color change detection unit calculates a degree of color change based on an output of a color sensor.   The surveillance camera device according to claim 3, wherein the proximity sensor and the color sensor are integrally formed sensor elements.

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