JP2005027023A - Camera system and monitoring method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology capable of more correctly determining the existence/absence of the occurrence of a certain event (existence of invader, etc., ) in a camera system in which a plurality of cameras are connected. <P>SOLUTION: This camera system is provided with the plurality of cameras 1a and 1b. Also, an external input device 2a such as a passive sensor is connected to the camera 1a and detects a state change. The camera 1b includes a trigger detecting part 11 by image processing and detects a state change by image processing, etc., due to moving body detection. The existence/absence of the occurrence of a prescribed event is determined on the basis of not only one state change but both of these two state changes. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a camera system (for example, a surveillance camera system) to which a plurality of cameras are connected, and a technology related thereto.
[0002]
[Prior art]
There is a camera system in which a plurality of cameras are connected (for example, see Patent Document 1). Such a camera system is used as a surveillance camera system for detecting an intruder or the like.
[0003]
In Patent Document 1, an example of such a system is shown. Specifically, there is described a system that captures an image of an object by operating the orientation of at least one of a plurality of cameras when an intruder is detected.
[0004]
[Patent Document 1]
JP 2002-150441 A
[0005]
[Problems to be solved by the invention]
In general, various detection means exist for detecting an intruder or the like. For example, there are those that detect a person using a photographed image of a camera, and those that detect a person using a sound detection sensor or an infrared detection sensor.
[0006]
However, it is difficult to perform accurate detection under any environment with one detection means. For example, even when moving object detection using a captured image of a camera is performed, the detection result may be inaccurate under circumstances such as dark lighting. Further, when a sound detection sensor is used, erroneous detection due to noise may be performed. Similarly, when an infrared sensor is used, a small animal or a facsimile communication device may be erroneously detected.
[0007]
In view of the above problems, the present invention provides a technique capable of more accurately determining whether or not a certain event (the presence of an intruder, etc.) has occurred in a camera system in which a plurality of cameras are connected. For the purpose.
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention of claim 1 is a camera system to which a plurality of cameras including a first camera and a second camera are connected, and is associated with the first camera. First detection means for detecting a first state change corresponding to the occurrence, and second detection means associated with the second camera and detecting a second state change corresponding to the occurrence of the predetermined event; Determining means for determining whether or not the predetermined event has occurred based on the first state change and the second state change.
[0009]
According to a second aspect of the present invention, in the camera system according to the first aspect of the present invention, the second camera captures the first camera when the first state change is detected by the first detection means. An area including at least a part of the area is imaged, and the second detection unit detects the second state change based on the content captured by the second camera.
[0010]
According to a third aspect of the present invention, in the camera system according to the second aspect of the present invention, when the first state change is detected, the first camera is turned on to an illumination unit associated with the first camera. An instruction signal is output.
[0011]
According to a fourth aspect of the present invention, in the camera system according to any one of the first to third aspects of the present invention, the second detection means is based on moving object detection or luminance difference detection based on the content captured by the second camera. The second state change is detected.
[0012]
A fifth aspect of the present invention is the camera system according to any one of the first to fourth aspects, further comprising a server computer connected to both the first camera and the second camera, The determination means is provided in the server computer.
[0013]
According to a sixth aspect of the present invention, in the camera system according to any one of the first to fourth aspects, the determination unit is provided in the second camera, and the first state change is the first state change. The second camera is notified from the first camera through a connection between the output terminal of the camera and the input terminal of the second camera.
[0014]
The invention of claim 7 is a monitoring method using a camera system in which a plurality of cameras including a first camera and a second camera are connected, wherein a) a first detection means associated with the first camera is provided. And detecting a first state change corresponding to the occurrence of the predetermined event, and b) using a second detecting means associated with the second camera, the second corresponding to the occurrence of the predetermined event. And c) determining whether or not the predetermined event has occurred based on the first state change and the second state change.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0016]
<A. First Embodiment>
<Overall configuration>
FIG. 1 is a diagram showing a configuration of a camera system 100A according to the first embodiment of the present invention. The camera system 100A is used for monitoring purposes.
[0017]
The camera system 100A includes a plurality of network cameras (hereinafter simply referred to as cameras) 1 (here, two cameras 1a and 1b) and a server computer (hereinafter also simply referred to as a server) 5.
[0018]
The plurality of cameras 1a and 1b and the server 5 are network-connected using a network connection line NL. More specifically, the cameras 1a and 1b and the server 5 are connected to each other via a LAN (local area network) cable, a wireless LAN device, a network hub (not shown), or the like. When the server 5 is located at a remote place, the plurality of cameras 1a, 1b and the server 5 may be connected via the Internet or a dedicated line.
[0019]
The server 5 displays the images of the cameras 1a to 1e and provides a GUI (graphical user interface) for controlling the camera. When the server 5 receives the camera abnormality notification, the server 5 displays on the monitor screen of the server 5 which camera abnormality has occurred and the content of the abnormality. The cameras 1 a and 1 b perform monitoring processing in cooperation by exchanging information with each other via the server 5.
[0020]
The camera system 100A has two subsystems 10a and 10b. The subsystem 10a has a camera 1a, an external input device 2a, and an external output device 3a, and the subsystem 10b has a camera 1b, an external input device 2b, and an external output device 3b. As described above, each subsystem 10a is constituted by a camera and its input / output devices.
[0021]
Since these two subsystems 10a and 10b have almost the same configuration, for the sake of simplification of description, description will be given focusing on one subsystem 10a.
[0022]
The camera 1a of the subsystem 10a has a CPU (central processing unit) and a memory (storage unit). The camera 1a can perform the network communication function and various processes described later by executing a predetermined program stored in the memory.
[0023]
The camera 1a can capture and record an image, and can also perform voice input using a microphone or the like. In addition, the camera has various drive mechanisms for performing pan, tilt, and zoom drive operations of the camera when taking an image.
[0024]
Inside the camera 1a, there are provided a trigger detection unit 11 based on image processing, a trigger detection unit 12 based on audio processing, and a trigger control unit 13 that controls various triggers.
[0025]
The trigger detection unit 11 detects a change in the state of the subject in the image based on the image data captured by the camera 1a. Specifically, moving object detection and / or luminance difference detection is performed. The moving object detection is to detect the presence or absence of movement according to the presence or absence of a change between two frames. If a motion is detected by the moving body detection, trigger information (also referred to as a trigger signal) is output to the trigger control unit 13 in response to the detection of the motion. The luminance difference detection is for detecting the presence or absence of a subject change according to the presence or absence of a luminance change between two frames. If a luminance difference is detected by the luminance difference detection, trigger information is output to the trigger control unit 13 in response to the detection of the luminance difference.
[0026]
The trigger detection unit 12 detects a change in the state of sound around the sound data recorded by the camera 1a. Specifically, an audio signal input from a microphone is digitized by A / D conversion, and when a sound pressure with a level higher than a preset level is detected, it is detected as an abnormal sound. At this time, the trigger detection unit 12 outputs trigger information to the trigger control unit 13 in response to the detection of the abnormal sound.
[0027]
Furthermore, a plurality of external input devices 2a are connected to the camera 1a. Specifically, an input terminal TI among I / O terminals (input / output terminals) of the camera 1a and an output terminal TO of each external input device 2a are connected via a signal line SL. When the external input device 2a detects a predetermined state change or the like, the external input device 2a outputs the detection result to the camera 1a as trigger information.
[0028]
Examples of the external input device 2a include a magnet switch, a push button, a passive sensor, a combination sensor, an infrared sensor, a flame sensor, a smoke sensor, a gas leak sensor, a glass break sensor, a water leak detection sensor, a mat switch, a tape switch, and a load switch. Various sensors such as can be used. The external input device 2a is not limited to these various devices as long as it can detect a change in state and output it as trigger information to the camera 1a.
[0029]
The trigger control unit 13 can receive trigger information from the trigger detection units 11 and 12 described above, and can also receive various trigger information from the external input device 2a.
[0030]
A plurality of external output devices 3a are connected to the camera 1a. Specifically, the input terminal TI of each external output device 3a is connected to the output terminal TO of the I / O terminals (input / output terminals) of the camera 1a. The external output device 3a performs a predetermined output based on an output instruction from the camera 1a. As the external output device 3a, for example, an illumination unit such as a light and an audio output device such as a buzzer or a bell can be used.
[0031]
The trigger control unit 13 transmits various output instructions to the server 5 and / or the external output device 3a based on various trigger information from the trigger detection units 11 and 12 and the external input device 2a. The trigger control unit 13 can also transmit a detection start instruction to the trigger detection unit 11.
[0032]
Thus, the camera 1a includes the trigger detection units 11 and 12 and is connected to the external input device 2a having a trigger detection function. In other words, it can be expressed that the camera 1a is associated with the trigger detection units 11 and 12 and the external input device 2a. The same applies to the camera 1b.
[0033]
<Example layout>
FIG. 2 is a plan view showing a layout example of each element of the camera system 100A. Here, a system for monitoring whether or not a suspicious person has entered the living room RM is assumed.
[0034]
As shown in FIG. 2, two cameras 1a and 1b are arranged in the room RM. Specifically, the cameras 1a and 1b are installed at different positions on the ceiling.
[0035]
In principle, one camera 1a photographs the window 41 and its surroundings, and the other camera 1b photographs the door 42 and its surroundings. That is, each camera performs a monitoring operation in cooperation by sharing a different area and shooting.
[0036]
In addition, a passive sensor 21 that detects infrared rays is provided around the window 41. The passive sensor 21 is connected to the camera 1a and functions as an external input device 2a associated with the camera 1a.
[0037]
A long and narrow elliptical region drawn by a dotted line in FIG. 2 indicates a detection target region R1 of the passive sensor 21. The passive sensor 21 can detect the presence or absence of a heating element within the detection target region R1 by receiving infrared rays. Here, not only the window 41 but also the facsimile communication device 43 arranged around the window 41 exists in the detection target region R1. Therefore, the passive sensor 21 may react not only to the suspicious person in the detection target region R1, but also to the facsimile communication device 43 that has started the reception operation at night, for example.
[0038]
Further, a light 31 is arranged toward the window 41. The light 31 is connected to the camera 1a and functions as an external output device 3a associated with the camera 1a. The light 31 is normally in an off state (non-lighting state), and lights up in response to an output instruction (lighting instruction) from the trigger control unit 13 of the camera 1a. When the light 31 is turned on, the area around the window 41 is illuminated.
[0039]
On the other hand, a mat switch 26 is disposed in the vicinity of the door 42. The mat switch 26 is connected to the camera 1b and functions as an external input device 2b associated with the camera 1b. The mat switch 26 detects the presence of a person or an object having a predetermined weight or more on the surface, and transmits it to the camera 1a.
[0040]
In addition, the server 5 is not disposed in the living room RM, but is disposed in another living room or the like (for example, a monitoring room or the like). In addition, the server 5 may be arrange | positioned in the place (remote) far away from the building containing this living room.
[0041]
<Operation>
FIG. 3 is a diagram illustrating a state in which the shooting range of the camera 1b is changed when a suspicious person enters. FIG. 4 is a flowchart showing an operation example in the camera system 100A. Hereinafter, an operation for detecting the occurrence of an abnormal event will be described with reference to these drawings. More specifically, the discovery operation for a suspicious person or the like will be described.
[0042]
Assume that predetermined trigger information TG1 related to the camera 1a is detected in step S1 of FIG. Specifically, when the passive sensor 21 (FIGS. 2 and 3) detects a predetermined state change and notifies the camera 1a, the camera 1a recognizes the predetermined state change, in other words, the occurrence of a trigger (trigger detection). Trigger information TG1 is also generated.
[0043]
Here, this state change detected by the passive sensor 21 corresponds to the occurrence of an abnormal event such as the entry of a suspicious person. However, determining whether or not an abnormal event has occurred based only on the detection signal from the passive sensor 21 does not necessarily have sufficient reliability. As described above, the passive sensor 21 may react not only to the suspicious person 44 as shown in FIG. 3 but also to the facsimile communication device 43 arranged in the vicinity to detect a change in state. Because there is.
[0044]
Next, the camera 1a notifies the server 5 of trigger information TG1 detected by the passive sensor 21 through network communication using a LAN or the like (step S2).
[0045]
When receiving the trigger information TG1 from the camera 1a, the server 5 returns a reception confirmation to the camera 1a (step S3).
[0046]
Upon receipt of this reception confirmation, the camera 1a transmits a lighting instruction to the light 31 by the trigger control unit 13 (step S4). By lighting the light, the vicinity of the window 41 can be illuminated and a warning to the suspicious person 44 can be given.
[0047]
Further, when the server 5 receives the trigger information TG1 from the camera 1a, in response to the trigger information TG1, the server 5 transmits (notifies) an operation instruction for changing the shooting area of the camera 1b to another camera 1b. (Step S5). Specifically, the server 5 gives a new target value of the pan angle, tilt angle, and zoom magnification (viewing angle) to the camera 1b and instructs to operate so as to realize the target value. . The camera 1b can photograph the object near the window 41 from an angle different from that of the camera 1a by changing the photographing angle.
[0048]
As the target value, as shown in FIG. 3, a value that is realized as a range in which the new shooting range of the camera 1b includes an overlapping range with the shooting range of the camera 1a is set. Note that the new shooting range in FIG. 3 is such that the camera 1a itself can also be shot.
[0049]
This target value is stored in advance in a data table TBL (see FIG. 5) stored in storage means (hard disk and / or memory, etc.) of the server 5. The server 5 sends out an instruction based on the target value stored in this data table.
[0050]
In the conceptual diagram of FIG. 5, various trigger information TG11, TG12,. . . A state in which target values related to the pan angle, tilt angle, and zoom magnification (viewing angle) of the other camera 1b are stored is shown. FIG. 5 also shows various trigger information TG21, TG22,. . . Also shown are target values for the pan angle, tilt angle, and zoom magnification (viewing angle) of the other camera 1a. Here, the trigger information TG11, TG12,. . . Indicates individual trigger information included in the trigger information TG1, and the trigger information TG21, TG22,. . . Indicates individual trigger information included in the trigger information TG2. Note that FIG. 5 illustrates the case where the posture angle of the camera with respect to the same camera is constant regardless of the type of trigger information, but a different posture may be indicated according to the type of trigger information. . For example, with respect to trigger information from a magnet switch (external input device 2a) provided in the window 41, a zoom magnification may be set so that the vicinity of the window 41 is enlarged and photographed.
[0051]
The camera 1b performs a driving operation in response to the operation instruction in step S5, and changes the pan angle, tilt angle, and zoom magnification of the camera 1b to target values (step S6).
[0052]
Thereby, the area | region where possibility that the suspicious person 44 exists is high can be intensively monitored by the two cameras 1a and 1b. In particular, when the imaging areas of the cameras 1a and 1b have non-overlapping areas, it becomes possible to find a suspicious person 44 existing in the non-overlapping areas. For example, as shown in FIG. 3, since the suspicious person 44 exists in an area outside the imaging range of the camera 1a, it cannot be captured by the camera 1a. However, since it exists in the imaging range after the change of the camera 1b, it becomes possible to capture the suspicious person 44 by the camera 1b.
[0053]
Next, the camera 1b performs a moving body detection process (step S7). When no moving object is detected, this process ends without notifying the server 5 of the trigger information for detecting the moving object. On the other hand, when a moving object is detected, the moving object detection information is notified to the server 5 as second trigger information TG2 (steps S8 and S9).
[0054]
Here, the state change detected by the moving object detection based on the photographed image of the camera 1b also corresponds to the occurrence of an abnormal event called intrusion of a suspicious person.
[0055]
Then, when receiving both the trigger information TG1 from the camera 1a and the trigger information (moving object detection) TG2 from the camera 1b, the server 5 determines in step S10 that an abnormal event has occurred. In other words, it is confirmed by the trigger information TG2 that the trigger information TG1 from the camera 1a correctly reflects the occurrence of the abnormal event. Then, the server 5 outputs abnormality information.
[0056]
Specifically, a warning output (warning display indicating “abnormality occurrence” using characters, graphics, or the like) is output to the display unit (display or the like) of the server 5. In addition, the server 5 may output a warning using sound or the like from a speaker. However, the present invention is not limited to this, and the server 5 may output an electronic mail including a similar warning output as abnormality information to a mail address of a designated mobile phone or the like.
[0057]
As described above, according to the camera system 100A, not only the trigger information TG1 corresponding to the occurrence of the abnormal event is detected by the camera 1a, but also the other trigger information TG2 corresponding to the occurrence of the abnormal event is generated. When further detected by the camera 1b, it is determined that the abnormal event has occurred. In other words, when both of the two trigger information TG1 and TG2 are detected, it is determined that an abnormal event has occurred, and when only one trigger information is detected, it is determined that no abnormal event has occurred. Therefore, the accuracy of the determination regarding the occurrence of the event can be improved as compared with the case where the occurrence of the abnormal event is determined only by the trigger information TG1 from the camera 1a. That is, erroneous determination can be prevented.
[0058]
Specifically, when the trigger information is detected by the passive sensor 21, the camera 1b captures an imaging region of the camera 1a and detects the presence of a moving object by moving object detection. Then, the server 5 detects another trigger information TG2 based on the moving object detection result by the camera 1b. Since the trigger information TG2 is detected based on the captured content (captured image) of the camera 1b including a lot of information, it is possible to particularly improve the accuracy of determination regarding the occurrence of an event.
[0059]
Further, when the trigger information TG1 is detected, the camera 1a outputs a lighting instruction signal to the light 31 (illumination unit) related to the camera 1a, so that it is possible to ensure the brightness at the time of shooting by the camera 1b. According to this, since the moving body detection process can be performed based on a brighter image, the accuracy of the detection result (moving body detection result) of the state change based on the photographing content of the camera 1b is improved. Therefore, it is possible to improve the accuracy of determination regarding event occurrence.
[0060]
Thus, by improving the accuracy of the determination regarding the occurrence of an event, the reliability of the system itself can be improved. Further, when notifying the occurrence of a predetermined event by e-mail, it is possible to reduce the number of e-mails notifying the erroneous determination result, and it is possible to reduce the e-mail communication cost.
[0061]
<B. Second Embodiment>
<Configuration>
FIG. 6 is a diagram showing a configuration of a camera system 100B according to the second embodiment of the present invention. The camera system 100B has a configuration similar to that of the camera system 100A. Below, it demonstrates centering around difference.
[0062]
First, the camera system 100B is different from the camera system 100A in that the server 5 is not provided. The occurrence of an abnormal event or the like is determined not by the server but by another camera (for example, camera 1b) that has received trigger information from a certain camera (for example, camera 1a). In other words, in the camera system 100B, a determination function for determining whether a predetermined event has occurred is not provided in the server, but is provided in at least one of the two cameras connected to each other.
[0063]
The camera 1a is not directly connected to the network, but is connected directly or indirectly to another camera 1b via an external input / output device or the like.
[0064]
Specifically, the output terminal TO of at least one external output device 3a of the camera 1a and the input terminal TI of at least one external input device 2b of the camera 1b are connected via a signal line SL. The input terminal TI of the external output device 3a is connected to the output terminal TO of the camera 1a via the signal line SL, and the output terminal TO of the external input device 2b is input to the camera 1b via the signal line SL. Connected to terminal TI. Therefore, the output terminal TO of the camera 1a and the input terminal TI of the camera 1b are connected via the external output device 3a and the external input device 2b.
[0065]
Then, the camera 1a controls the state of the output signal at the output terminal of the corresponding external output device 3a according to the type of the detected trigger information. The camera 1a transmits the trigger information TG1 to the external input device 2b of the camera 1b and the trigger control unit 13 of the camera 1b by switching between a high level and a low level in the output signal. For example, the camera 1a transmits the trigger information TG1 by controlling the output signal so that it is maintained at a high level when it is normal and is changed to a low level when it is abnormal. Alternatively, the high level and the low level may be used in reverse.
[0066]
According to such connection, various types of information (such as information on state change) can be exchanged without using a server and without using a network connection. This connection is not limited to a wired connection using the signal line SL or the like, and may be realized by a wireless connection by various wireless communication means.
[0067]
Alternatively, information can be exchanged without connecting the output terminal of the camera 1a and the input terminal of the camera 1b. For example, information may be exchanged between the cameras 1a and 1b using the external output device 3a and the external input device 2b.
[0068]
Specifically, when the trigger information TG1 is detected, the camera 1a sends an output signal to the external output device 3a associated with the camera 1a, and the camera 1b transmits the external input device associated with the camera 1b. The input signal from 2b may be received. For example, a sound output device such as a buzzer (or bell) that emits a predetermined sound is used as the external output device 3a, and a sound detection device that detects the sound is used as the external input device 2b. When the external input device 2b detects a buzzer sound generated by the external output device 3a, the external input device 2b transmits trigger information TG1 to the camera 1b. According to this, the camera 1b can receive the trigger information TG1 from the camera 1a. That is, various information can be exchanged between the cameras 1a and 1b without connecting the cameras 1a and 1b to each other.
[0069]
<Operation>
FIG. 7 is a flowchart showing an operation example in the camera system 100B. Below, the operation | movement which detects generation | occurrence | production of the abnormal event in this 2nd Embodiment is demonstrated.
[0070]
First, in step S21, as in the first embodiment, it is assumed that the passive sensor 21 (external input device 2a) detects a predetermined state change and notifies the camera 1a.
[0071]
Next, the camera 1a transmits trigger information TG1 from the passive sensor 21 or the like to the camera 1b (step S22). Specifically, the camera 1a uses the signal line connection between the output terminal TO of a certain external output device 3a and the input terminal TI of the corresponding external input device 2b to transmit the trigger information TG1 to the external input device 2b. To the camera 1b. The trigger control unit 13 of the camera 1b connected to the external input device 2b recognizes the state change related to the camera 1a by receiving the trigger information TG1 through the signal line connection. Thus, the state change related to the camera 1a is notified from the camera 1a to the trigger control unit 13 of the camera 1b as the trigger signal TG1 through the connection between the output terminal of the camera 1a and the input terminal of the camera 1b. The
[0072]
Further, the camera 1a transmits a lighting instruction to the light 31 (external output device 3a) by the trigger control unit 13 (step S24). By lighting the light, the vicinity of the window 41 is illuminated and a warning to the suspicious person 44 is given.
[0073]
In response to the notification of the trigger information TG1 in step S22, the other camera 1b performs operation control for changing the shooting area of the camera 1b (step S25). Specifically, the camera 1b performs control so as to realize new target values of the pan angle, tilt angle, and zoom magnification (viewing angle). The new target value may be determined using the data table TBL stored in the storage means (memory or the like) inside the camera 1b. A data table TBL similar to that shown in FIG. 5 can be used. However, the information regarding the angle setting of the other camera 1a is unnecessary.
[0074]
Next, the camera 1b performs a moving body detection process (step S27). Then, branch processing is performed according to the result (step S28). If no moving object is detected, this process ends. On the other hand, when a moving object is detected, it is determined that an abnormal event has occurred (step S29).
[0075]
Specifically, the trigger control unit 13 of the camera 1b recognizes a state change related to the camera 1a by receiving trigger information (moving object detection) TG2 from the trigger detection unit 11 of the camera 1b.
[0076]
When the trigger control unit 13 of the camera 1b receives both the trigger information TG1 from the camera 1a and the trigger information (moving object detection) TG2 from the trigger detection unit 11 of the camera 1b, the trigger control unit 13 determines that an abnormal event has occurred. To do. In other words, the trigger information TG2 is also used to determine that the trigger information TG1 from the camera 1a correctly reflects the occurrence of the abnormal event.
[0077]
Then, the camera 1b outputs abnormality information (step S30).
[0078]
Specifically, a predetermined alarm is output to one of the external output devices 3b of the camera 1b. For example, a buzzer sound, a siren sound, etc. are generated. In the case where the camera 1b has a network connection function, an e-mail including a warning output by characters or the like may be output as abnormality information to a mail address of a designated mobile phone or the like.
[0079]
As described above, according to the camera system 100B, advantages similar to those of the camera system 100A can be obtained.
[0080]
Further, according to the camera system 100B, it is possible to accurately determine the occurrence of an abnormal state using a simple system without using a server.
[0081]
<C. Modification>
Although the embodiments of the present invention have been described above, the present invention is not limited to the contents described above.
[0082]
For example, in each of the above embodiments, the case where two cameras 1a and 1b are used has been described. However, the present invention is not limited to this, and three or more cameras may be used. Three or more cameras 1a, 1b, 1c, 1d, 1e,. . . , The other cameras 1b, 1c, 1d, 1e,... That have received the trigger information TG1 from one camera 1a. . . A plurality of other cameras (for example, three cameras 1b, 1c, and 1d) may perform a confirmation operation for improving the reliability of the trigger information TG1. Specifically, all three other cameras 1b, 1c, and 1d that have received the trigger information TG1 from the camera 1a perform moving object detection processing, and whether or not an abnormal state has occurred due to a majority decision regarding the detection result. May be determined. Or you may make it determine the presence or absence of generation | occurrence | production of an abnormal state, after weighting with respect to the moving body detection result by each camera according to the position of each installed camera 1b, 1c, 1d.
[0083]
In each of the above embodiments, the case where the camera 1a gives an output instruction to the light 31 has been described. However, the camera 1a may give an audio output instruction to an external output device 3a such as a buzzer or a siren. . Furthermore, in this case, in order to avoid erroneous detection due to interference, the sound sensing device of the external input device 2b of the camera 1b does not detect this sound while the sound output instruction is transmitted by the camera 1a. It is preferable that the detection signal from the voice sensing device is invalidated. For example, immediately after receiving the trigger information TG1 from the camera 1a in step S3 in FIG. 4, the server 5 invalidates the detection signal from the voice sensing device connected to the camera 1b, and then confirms the receipt of the camera 1a. You may make it reply to.
[0084]
Further, in each of the embodiments described above, the case where a certain state change is detected by the passive sensor 21 has been described. However, there are various types of state changes, and each state change has various types. Detected by various elements.
[0085]
For example, the state change may be detected by moving object detection based on the photographing content of the camera 1a, and the state change may be detected by moving body detection based on the photographing content of the camera 1b. Then, it may be determined that an abnormal event has occurred when both of these two state changes are detected. Even in this case, since the occurrence of the abnormal event is determined by the logical sum of the two detection results by the cameras 1a and 1b, the reliability of the determination result can be improved. In addition, since the camera 1b can capture an object near the window 41 from an angle different from that of the camera 1a, it is possible to avoid erroneous detection in the case of determining with only an image from one angle.
[0086]
Another example of detecting a change in state is one that detects the destruction of the camera itself. It is very useful to grasp the state of the camera itself when the camera itself is destroyed by an intruder or the like.
[0087]
Specifically, in the first embodiment, each camera 1a, 1b may transmit to the server 5 by a polling operation that each camera 1a, 1b is operating normally. The server 5 can detect that an abnormality has occurred in the camera by detecting that the transmission from either one of the cameras 1a and 1b is not received within a predetermined period. For example, the server 5 that has detected the abnormality of the camera 1a may transmit the trigger information TG1 to the camera 1b.
[0088]
Alternatively, in the second embodiment, one of the plurality of output signals is controlled to be maintained at a high level when the camera 1a is normal and to be changed to a low level when the camera 1a is abnormal. Trigger information TG1 indicating camera abnormality may be transmitted to the camera 1b.
[0089]
Here, the fact that the camera itself is in an abnormal state is simply referred to as “camera abnormality”, and the trigger information indicating the camera abnormality is also referred to as “camera abnormality trigger”.
[0090]
In each modification, when an abnormality occurs in one camera (for example, the camera 1a), the other camera 1b changes the shooting range of the camera 1b itself so as to shoot the camera 1a in an abnormal state. Then, the damaged state of the camera 1a itself is confirmed. Specifically, the camera 1b can check the presence / absence of the camera 1a and the appearance of the outer shape by comparing a new photographed image with a normal image stored in the camera 1a. It is. When determining that the camera 1a does not exist or is damaged, the trigger detection unit 11 of the camera 1b outputs trigger information TG2.
[0091]
In this way, the presence / absence of occurrence of an abnormal event related to the camera 1a (more specifically, damage on the outer shape of the camera 1a) is determined based on both the camera abnormal trigger TG1 and the trigger information TG2 by image processing. You may make it do.
[0092]
【The invention's effect】
As described above, according to the first to eighth aspects of the invention, the accuracy in determining the occurrence of an event can be improved.
[0093]
In particular, according to the second aspect of the present invention, it is possible to further improve the accuracy of determination relating to the occurrence of an event.
[0094]
According to the third aspect of the present invention, the brightness at the time of shooting can be ensured, so that the accuracy of determination regarding the occurrence of an event can be improved.
[0095]
Furthermore, according to the fourth aspect of the present invention, since the second state change is detected by the moving object detection or the luminance difference detection based on the content captured by the second camera, the determination regarding the occurrence of the event can be performed more accurately. Is possible.
[0096]
According to the sixth aspect of the present invention, it is possible to transmit information relating to a state change without using a server computer.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a configuration of a camera system 100A according to a first embodiment.
FIG. 2 is a diagram illustrating a layout example of each element of the camera system 100A.
FIG. 3 is a diagram illustrating a state in which a shooting range of the camera 1b is changed.
FIG. 4 is a flowchart showing an operation example in the camera system 100A.
FIG. 5 is a diagram showing an outline of a data table TBL.
FIG. 6 is a diagram showing a configuration of a camera system 100B according to a second embodiment.
FIG. 7 is a flowchart showing an operation example in the camera system 100B.
[Explanation of symbols]
100A, 100B camera system
11, 12 Trigger detection unit
13 Trigger control unit
1a-1e camera
21 Passive sensor
26 Matt switch
41 windows
43 Facsimile communication equipment
44 Suspicious person
NL network connection line
R1 detection target area
RM living room
SL signal line
TG1, TG2 Trigger information
TI input terminal
TO output terminal

Claims (8)

A camera system to which a plurality of cameras including a first camera and a second camera are connected,
First detection means associated with the first camera and detecting a first state change corresponding to the occurrence of a predetermined event;
Second detection means associated with the second camera and detecting a second state change corresponding to the occurrence of the predetermined event;
Determination means for determining whether or not the predetermined event has occurred based on the first state change and the second state change;
A camera system comprising: The camera system according to claim 1,
The second camera captures an area including at least a part of an imaging area of the first camera when the first state change is detected by the first detection unit;
The camera system characterized in that the second detection means detects the second state change on the basis of the content of the image taken by the second camera. The camera system according to claim 2,
When the first state change is detected, the first camera outputs a lighting instruction signal to an illumination unit associated with the first camera. The camera system according to any one of claims 1 to 3,
The camera system according to claim 2, wherein the second detection means detects the second state change by moving object detection or luminance difference detection based on the content captured by the second camera. The camera system according to any one of claims 1 to 4,
A server computer connected to both the first camera and the second camera;
Further comprising
The determination system is provided in the server computer. The camera system according to any one of claims 1 to 4,
The determination means is provided in the second camera,
The first state change is notified from the first camera to the second camera via a connection between an output terminal of the first camera and an input terminal of the second camera. Camera system. A monitoring method using a camera system to which a plurality of cameras including a first camera and a second camera are connected,
a) detecting a first state change corresponding to the occurrence of a predetermined event using first detection means associated with the first camera;
b) detecting a second state change corresponding to the occurrence of the predetermined event using second detection means associated with the second camera;
c) determining whether or not the predetermined event has occurred based on the first state change and the second state change;
The monitoring method characterized by including. A camera system to which a plurality of cameras including a first camera and a second camera are connected,
First detecting means for detecting a first state change corresponding to occurrence of a predetermined event related to the first camera;
A second detection means built in or connected to the second camera for detecting a second state change corresponding to the occurrence of the predetermined event;
Determination means for determining whether or not the predetermined event has occurred based on the first state change and the second state change;
A camera system comprising:

Images