JP2003111064A - Monitoring camera system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a monitoring camera system capable of detecting a changed imaging direction of a monitoring camera by organically combining a function of determining the changed imaging direction on the basis of angular velocity information detected by an angular velocity sensor with a simple image processing function. SOLUTION: The magnitude of an angular velocity is classified into four categories; a high angular velocity, a medium angular velocity, a low angular velocity, and no angular velocity, and the revision of the imaging direction of the monitoring camera is detected by only the magnitude of the angular velocity for the high angular velocity and by the magnification of the angular velocity and its duration time for the medium angular velocity. Further, the change of the imaging direction is detected by combination of detection on the basis of the magnitude of the angular velocity and its duration time with detection of an image change on the basis of monitoring area image change information converted by using simple image processing for the low angular velocity. The change of the imaging direction of the monitoring camera is detected by deciding the detection of an image change on the basis of the monitoring area image change information for no angular velocity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surveillance camera device capable of detecting that an image pickup direction has been changed. In particular,
The present invention relates to a surveillance camera device capable of detecting fraudulent behavior in which a suspicious person is not imaged by fraudulently changing the imaging direction of a surveillance camera.

[0002]

2. Description of the Related Art Conventionally, a surveillance camera for picking up an image of a store has set an image pickup direction of the surveillance camera so as to pick up an image of an entrance / exit, a shelf of important products, a cash register, etc., and sequentially records picked-up image information. However, if a person who engages in fraudulent acts such as shoplifting changes the image capturing direction of the surveillance camera, he or she cannot capture images of important products and the like, making monitoring difficult. Therefore, a surveillance camera that can detect that the imaging direction has been changed has been proposed.

For example, in Japanese Patent Laid-Open No. 2000-285328, there is one in which a gyro sensor detects an angular velocity due to the rotation of a surveillance camera to determine whether or not the imaging direction is changed. Some recent surveillance cameras have a simple image processing function of detecting a predetermined amount of change from the captured image information. By using such an image processing function, it is possible to determine that the imaging direction of the camera has been changed when the amount of change detected from the image information is large.

[0004]

However, in the determination using the conventional gyro sensor, if the sensitivity of the angular velocity information detected by the gyro sensor is improved,
It is determined that the imaging direction is changed with a slight vibration. That is, there is a problem that the vibration due to the truck is erroneously determined as the change of the image pickup direction. On the contrary, if the sensitivity of the angular velocity information detected by the gyro sensor is reduced, there is a problem that the detection cannot be performed when the imaging direction of the surveillance camera is gently changed. Further, in the determination when using a simple image processing function, it is difficult to distinguish from illumination fluctuations and other moving objects that appear in a large size, and when a dark place is imaged, changes on the image are less likely to appear, There is also a problem that image changes cannot be detected.

Therefore, the present invention has been made in order to solve the above problems, and has a function of determining a change in the image pickup direction based on angular velocity information detected by a gyro sensor and a simple image processing function. It is an object of the present invention to provide a surveillance camera device capable of detecting a change in the image pickup direction of the surveillance camera by combining the above.

[0006]

Means for Solving the Problems The present inventor has conducted extensive research to solve the above-mentioned conventional problems. As a result, the change in the image capturing direction due to the rotation of the surveillance camera is detected by the detection of the change in the image capturing direction by the angular velocity information and the simple image processing depending on the magnitude of the angular velocity of the angular velocity information measured by the angular velocity sensor such as the gyro sensor. It is possible to detect a change in the imaging direction of the surveillance camera by organically combining the detection of the image change based on the monitoring region image change information obtained by converting the obtained monitoring region image information into the predetermined image change amount. found.

Based on the above research results, the following inventions are provided. One aspect of the surveillance camera device of the present invention detects an image capturing unit that captures an image of a monitoring region in a predetermined direction and a change in the image capturing direction of the image capturing unit as angular velocity information in a predetermined one direction or a plurality of predetermined different directions. And one or more angular velocity sensors, and a control unit that detects a change in the imaging direction of the imaging unit based on the angular velocity information detected by the angular velocity sensor and the monitoring area image information captured by the imaging unit. An image processing means for generating monitoring area image change information from the monitoring area image information imaged by the imaging section, and the angular velocity information detected by the angular velocity sensor is lower than or equal to a lower angular velocity than a predetermined low angular velocity duration threshold value or more. An image is taken when the monitoring area image change information generated by the image processing means continues and is equal to or more than a predetermined change amount as compared with the reference image change information. And direction change determination means determines that the direction changes, when the imaging direction change is determined by the direction change determination unit, a monitoring camera apparatus and an output means for outputting a detection of the image pickup direction changing.

According to this structure, when the angular velocity is low and the change in the image pickup direction is detected when the change in the image exceeds the change due to the vibration, it is determined that the image pickup direction is changed. The operation can be detected.
It should be noted that the image change above a predetermined level refers to a change that exceeds a minute change due to flicker of a fluorescent lamp or intrusion of a shadow. However, it is possible to exclude a change that is clearly determined to be a change in illumination or a change due to light or a shadow.

Another aspect of the surveillance camera apparatus of the present invention is
The above-described direction change determination means is a monitoring camera device that determines that the image capturing direction is changed when the angular velocity information detected by the angular velocity sensor continues at a medium angular velocity or higher for a predetermined medium angular velocity duration time threshold or longer. According to this, when the operation of changing the image pickup direction of the surveillance camera is normally performed, the medium angular velocity continues, so that it can be immediately determined that the image pickup direction is changed regardless of whether or not the image changes. Here, the medium angular velocity is an angular velocity at which the surveillance camera body is neither abrupt nor slow, and the camera body normally rotates.

Another aspect of the surveillance camera device of the present invention is
The above-described direction change determination means is a monitoring camera device that determines that the image capturing direction is changed when the angular velocity detected by the angular velocity sensor is high angular velocity information. According to this, in the state where the angular velocity becomes high, it is possible to quickly detect the state where the surveillance camera body is rapidly turned.

Another aspect of the surveillance camera apparatus of the present invention is
Furthermore, the illuminance sensor for detecting the illuminance information of the monitoring area is provided, and the above-mentioned direction change determination means is such that the illuminance information detected by the illuminance sensor does not change significantly and is equal to or greater than a predetermined reference illuminance value, and the image The surveillance camera device determines that the imaging direction is changed when the monitoring area image change information generated by the processing unit is equal to or larger than a predetermined change amount that can be determined as a large change compared with the reference image change information. Here, the fact that the illuminance information does not change significantly means that there is no abrupt change such as ON / OFF of the room lighting. The illuminance equal to or higher than the predetermined reference illuminance value is an illuminance that is not extremely dark like at night and is not extremely bright as sunlight is directly incident. The large change means a change in the image over almost the entire area of the image. According to this, the influence of the image change due to the illumination change can be eliminated, and the image change can be determined by using the highly reliable image in the state suitable for imaging. Therefore, it is possible to quickly detect the change in the imaging direction based on the image change over almost the entire area.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to the drawings. The embodiments described below are for the purpose of explanation, and do not limit the scope of the present invention. Therefore, those skilled in the art can adopt embodiments in which each of these elements or all elements are replaced by equivalents thereof, and these embodiments are also included in the scope of the present invention.

FIG. 1 is a diagram showing the overall configuration of a monitoring system. The monitoring system 100 includes a monitoring camera 101 (cameras 101a to 101d in the figure), a controller 102, a monitor 103, and a speaker 104.
Is equipped with. The monitoring area image information obtained by capturing a predetermined monitoring area by the monitoring camera 101 is the controller 102.
Sent to. When the monitoring camera 101 detects that the imaging direction of the monitoring camera has been changed (hereinafter referred to as “imaging direction change”), the monitoring camera 101 notifies the controller 102 that an abnormality has occurred. The surveillance camera 101 is provided with a RAM and can store a predetermined number of surveillance area image information in a ring buffer shape.

Therefore, when an abnormality is detected, the controller 102 stores the monitoring area image information before the abnormality occurrence, the monitoring area image information at the time of the abnormality occurrence, and the current monitoring area image information stored in the ring buffer. It is also possible to store it in the controller 102 as the evidence image information of the abnormality occurrence by transmitting the information to the controller 102. The plurality of monitoring cameras 101 (101a to 101d) are connected to each other by a daisy chain, and each monitoring camera 101 (101a to 101d) is connected via a predetermined monitoring camera 101a.
Various information can be transmitted from 101d) to the controller 102.

The controller 102 is a surveillance camera 101.
When the abnormality occurrence information including the evidence image information of the abnormality occurrence is received from the user, the user is notified of the abnormality occurrence by requesting the monitor 103 to display the abnormality warning and requesting the speaker 104 to output the warning sound. To do. Further, the evidence image of the abnormality occurrence received from the monitoring camera 101 is stored in a predetermined storage unit.

In the above-described monitoring system 100, the monitoring camera 101 has a function of determining the occurrence of an abnormality. However, by providing the controller 102 with the function of determining the occurrence of an abnormality, the controller 102 causes the monitoring camera 1 to operate.
It is also possible to receive the imaged monitoring area image information for detecting the abnormality occurrence from 01 and various information of the imaging direction change, and determine the abnormality occurrence based on the received various information. Furthermore, the surveillance camera 101 and the controller 10
It is also possible to separately provide the function for determining the occurrence of abnormality in 2. Hereinafter, a case where the surveillance camera 101 has a function of determining whether an abnormality has occurred will be described as an example.

FIG. 2 is a diagram showing the structure of the surveillance camera. The monitoring camera 101 includes a control unit 201 and an imaging unit 20.
2, an illuminance sensor 203, a gyro sensor 204, a storage unit 205, a communication unit 206, a monitor I / F 207, and a display unit 208. The control unit 201 controls the aperture of the lens 221 and the shutter speed of the image sensor 222 of the image capturing unit 202 so that the image information is suitable for monitoring, and displays the monitoring region image information obtained by capturing a predetermined monitoring region by the image capturing unit 202. Enter periodically. Here, the monitoring area image information input to the control unit 201 is digital image information.
Further, the control unit 201 stores the monitoring area image information input from the imaging unit 202 in the storage unit 205.

The control unit 201 also includes an illuminance sensor 203.
The illuminance information obtained by measuring the illuminance of the external environment light of the surveillance camera 101 and the angular velocity information obtained by measuring the angular velocity for detecting the change in the image capturing direction of the surveillance camera 101 by the gyro sensor 204 are periodically input. Here, by disposing two gyro sensors 204 inside the surveillance camera 101, the angular velocity in the horizontal direction and the angular velocity in the vertical direction can be measured. Further, the control unit 201 is configured to periodically input the angular velocity information from the gyro sensor 204 and the illuminance sensor 20.
A change in the image capturing direction of the monitoring camera 101 is detected on the basis of the illuminance information from No. 3 and the monitoring area image information from the image capturing unit 202.

The communication unit 206 performs LAN communication between the monitoring camera 101 and the controller 102, and sends various kinds of information such as abnormality information at the time of occurrence of an abnormality such as a change in the imaging direction, monitoring area image information, and sensor information to the controller 102. It transmits or receives various request information from the controller 102. In addition, the display unit 208 indicates to the user the occurrence of an abnormality such as a change in the image capturing direction, the energization status of the surveillance camera 101, etc.
Notify by the color of light emitted and the blinking method.

Further, by connecting the monitor to the monitoring camera 101, the monitor I / F 207 is connected to the monitoring camera 102 so that the image information captured by the monitoring camera 101 can be displayed without going through the controller 102. I have it.

FIG. 3 is an example of a block diagram showing the functional blocks of the control unit of the surveillance camera. The control unit 201 includes an image pickup unit 301, an image processing unit 302, and a sensor information input unit 3
03, direction change determination means 304 and output means 305. The imaging unit 301 inputs the monitoring area image information imaged by the imaging unit 202 by controlling the aperture of the lens 221 and the shutter speed of the imaging element 222 of the imaging unit 202 so that the image information is suitable for monitoring. The input monitoring area image information is stored in the image information storage unit 311 of the storage unit 205.

The image processing means 302 divides the monitoring area image information input by the image pickup means 301 into a predetermined number of partial areas (hereinafter referred to as "blocks"), and an image calculated based on the image information of the blocks. The amount of change is calculated for each block. That is, the monitor area image change information is generated by converting each block into the image change amount from the monitor area image information. Further, the generated monitoring area image change information is stored in the storage unit 2.
05 image change information storage unit 312. here,
The image change amount includes an edge amount indicating the gradient of the brightness of the block, a histogram change amount, and the like. Further, the number of blocks is a predetermined number (n * m), for example, 8 * 8 =
It is divided into 64 pieces.

The sensor information input means 303 inputs the illuminance information measured by the illuminance sensor 203 and the angular velocity information measured by the gyro sensor 204, and stores it in the sensor information storage unit 313 of the storage unit 205.

The direction change determination means 304 is based on the illuminance information and the angular velocity information input by the sensor information input means 303, and the monitoring area image change information converted by the image processing means 302, that is, the magnitude and continuation of the angular velocity. The imaging direction of the monitoring camera 101 is changed based on the time, the amount of change between the monitoring area image change information of the change reference and the current monitoring area image change information, and the amount of change between the illuminance of the change reference and the current illuminance. It is determined whether or not there is a change in the imaging direction of the surveillance camera 101. Here, the value serving as the change reference for calculating the change amount of the monitoring area image change information and the change amount of the illuminance may be the previous value or the value several times before. That is, any value may be used as long as it is possible to determine whether or not the imaging direction of the monitoring camera 101 is changed based on the calculated change amount.

The output means 305 is the direction change determination means 30.
4 detects a change in the imaging direction of the monitoring camera 101, the monitoring area image information before the abnormality occurrence stored in the image information storage unit 311 in the form of a ring buffer, the monitoring area image information when the abnormality occurs, and Transmission information to the controller 102 including current monitoring area image information is generated and transmitted. Furthermore, the display unit 208 of the surveillance camera 101
Then, the user is notified of the occurrence of the abnormality by generating and outputting the output information of the occurrence of the abnormality.

Further, when outputting an image to a monitor connected via the monitor I / F 207, transmission information including image information is generated and the generated transmission information is transmitted to the monitor via the monitor I / F 207. Send. Further, based on the request from the controller 102 and various information transmission timings, transmission information to the controller 102 including necessary information is generated, and the generated transmission information is transmitted to the controller 102 via the communication unit 206.

FIG. 4 is an example of a diagram showing a flowchart of the image pickup direction change detection processing. First, monitoring area image information obtained by imaging a predetermined monitoring area is acquired, and the image information storage unit 3 is acquired.
11 (S401). Next, the illuminance sensor 203
Illuminance information measured by the gyro sensor 20
The angular velocity information measured by No. 4 is acquired and stored in the sensor information storage unit 313 (S402).

Next, based on the acquired monitoring area image information, it is divided into a predetermined number of blocks, and monitoring area image change information is calculated by calculating the image change amount for each block, and is stored in the image change information storage unit 312. Image processing such as storing is executed (S403). Next, based on the acquired angular velocity information and illuminance information, and the generated monitoring area image change information, it is determined whether or not the imaging direction of the monitoring camera 101 is changed, and the direction in which the imaging direction change of the monitoring camera 101 is detected. Change determination processing is executed (S404).

Next, it is determined whether or not a change in the image pickup direction of the surveillance camera 101 is detected (S405), and the surveillance camera 10
When the imaging direction change of 1 is detected (S405; Yes)
Is transmitted to the controller 102 including the monitoring area image information before the abnormality occurrence, the monitoring area image information when the abnormality occurs, and the current monitoring area image information stored in the image information storage unit 311 in a ring buffer shape. Abnormality occurrence processing such as generation and transmission of information or generation and output of abnormality occurrence output information to the display unit 208 of the monitoring camera 101 is executed (S406), and the process returns to step S401 to move to the next step. Wait until the processing timing.

On the other hand, when the change of the image pickup direction of the surveillance camera 101 is not detected (S405; No), the step S is performed.
The process returns to 401 and waits until the next processing timing. Here, the next processing timing is executed every predetermined time. For example, the process is executed every 16 msec.

FIG. 5 is an example of a diagram showing a flow chart of the direction change determination processing. First, various information necessary for the determination is acquired (S501). Here, the information necessary for the determination is the angular velocity information and the illuminance information measured at this processing timing, the monitoring area image change information calculated at this processing timing, the monitoring area image change information of the change reference, and the change reference Illuminance information. here,
The change reference value may be a value obtained at the previous processing timing or a value obtained at the processing timing several times before.

Next, based on the acquired illuminance information measured at this processing timing, the monitoring area image change information calculated at this processing timing, the change reference monitoring area image change information, and the change reference illuminance information. ,
The amount of change in the monitoring area image change information and the amount of change in illuminance are calculated (S502). Next, based on the magnitude of the acquired angular velocity, a determination process is performed to detect a change in the image capturing direction at a high angular velocity such that the image capturing direction is changed by hitting the surveillance camera body with a stick (S50).
3).

Next, based on the magnitude and duration of the acquired angular velocity, a determination process for detecting a change in the image pickup direction with a medium angular velocity is executed (S504). Next, based on the magnitude of the acquired angular velocity, the duration, and the amount of change in the monitoring area image change information, a determination process for detecting a change in the imaging direction at a low angular velocity that gently changes the imaging direction is executed. Yes (S505).

Next, loosen the screw of the mounting bracket of the surveillance camera, and gently change the imaging direction of the surveillance camera.
A determination process for detecting a change in the image capturing direction in which the image capturing direction of the surveillance camera is changed so that the angular velocity is not detected is executed (S506).

Next, steps S503 to S50 described above.
In 6, it is determined whether or not a change in the image capturing direction of the surveillance camera has been detected (S507). That is, a high angular velocity imaging direction change is detected, a medium angular velocity imaging direction change is detected, a low angular velocity imaging direction change is detected, and / or the monitoring camera's imaging direction is changed so that the angular velocity is not detected. It is determined whether or not it has been changed. When a change in the imaging direction of the surveillance camera is detected (S507; Yes)
Sets ON to the abnormality occurrence flag in order to identify that an abnormality has occurred due to the change of the imaging direction (S508),
The direction change determination process ends. On the other hand, when the change of the image capturing direction of the surveillance camera is not detected (S507; No),
The abnormality occurrence flag is set to OFF in order to identify that no abnormality has occurred due to the change of the imaging direction (S50
9) Then, the direction change determination process ends.

Referring to FIG. 10, high angular velocity direction change determination processing in step S503, medium angular velocity direction change determination processing in step S504, low angular velocity direction change determination processing in step S505, and imaging direction change determination without angular velocity in step S506. The processing will be described with respect to the magnitude of the angular velocity due to the rotation of the surveillance camera.

FIG. 10 is a diagram for explaining detection of a change in the image pickup direction of the surveillance camera based on the magnitude of the angular velocity. Figure 1
0 (a) is a diagram showing the relationship between the magnitude of the angular velocity for changing the imaging direction of the surveillance camera and the duration, and FIG.
FIG. 1B is a diagram showing a threshold value of the magnitude of angular velocity, and FIG.
0 (c) is a diagram showing a duration time for determining the change of the imaging direction.

As shown in FIG. 10A, when a high angular velocity is detected such that the surveillance camera is hit with a stick to change the imaging direction (thick line), the magnitude of the angular velocity changes greatly in a short time. However, there is a similar amount of rebound in the opposite direction. When a change in the imaging direction of the medium angular velocity is detected (thick line), the medium angular velocity continues for a predetermined time (hereinafter, referred to as “medium angular velocity duration threshold TMC2”), and there is a slight swing in the opposite direction. When a change in the imaging direction at a low angular velocity is detected (thin line), the low angular velocity remains for a predetermined time (hereinafter,
It is continued for more than "low angular velocity duration threshold value TMC3").

Further, as shown in FIG. 10B, the high angular velocity is a case where the angular velocity is equal to or higher than the high angular velocity threshold value GTh1.
The medium angular velocity is a case where the medium angular velocity is equal to or higher than the threshold value GTh2 and is lower than the high angular velocity threshold GTh1, and the low angular velocity is equal to or higher than the low angular velocity threshold GTh3 and the medium angular velocity threshold GT.
The case where the angular velocity is less than h2, and the case where there is no angular velocity is the case where the angular velocity is less than the low angular velocity threshold GTh3. It can be seen that the low angular velocity threshold GTh3 has higher sensitivity, and the higher the angular velocity threshold GTh1, the lower the sensitivity.

However, while the high angular velocity threshold value GTh1 can detect the change in the image pickup direction only by exceeding this threshold value, the medium angular velocity threshold value GTh2 and the low angular velocity threshold value GTh3 can be detected when the image pickup direction changes for a predetermined time or longer. Since the change is detected, there is no risk of false alarm, so the threshold can be set low. For example, the high angular velocity threshold GTh1 is 15 degrees / sec.
And the medium angular velocity threshold GTh2 is 9 degrees / sec,
The low angular velocity threshold GTh3 is 3 degrees / sec.

Further, as shown in FIG. 10 (c), the medium angular velocity duration time threshold value TMC2 and the low angular velocity duration time threshold value TMC.
The relationship of 3 is the medium angular velocity duration threshold TMC2 <= low angular velocity duration threshold TMC3. The low angular velocity duration threshold value TMC3 for detecting a gentle change in direction is the low angular velocity threshold value G.
Since Th3 may be low, the threshold value of the duration in the same direction is also detected long. On the contrary, if the threshold value of the duration of the medium angular velocity duration time TMC2 in the same direction is lengthened, the medium angular velocity threshold GTh2 must be continuously exceeded during that time, which causes a decrease in detection accuracy. Therefore, the medium angular velocity duration threshold T
MC2 should be set to a time shorter (or equivalent) than the low angular velocity duration threshold TMC3.

Further, the image change detection duration time threshold value TMC4
Has a different property from the medium angular velocity duration threshold TMC2 or the low angular velocity duration threshold TMC3. In order to detect whether the change in direction due to low angular velocity is detected by changing the image capturing direction of the surveillance camera, it is necessary to detect change in direction and change in image due to low angular velocity. But,
The detection of the angular velocity is easy to detect at the initial stage and the stop stage of changing the imaging direction of the surveillance camera.

On the other hand, in detecting an image change, there is little image change in the initial stage of changing the imaging direction of the surveillance camera, and it is difficult to detect it immediately. Therefore, it is desirable to set the image change detection continuation time threshold value TMC4 to a period that allows sufficient image change. For example, about 3 to 5 seconds is effective. Therefore, the image change detection duration threshold TMC4 has no correlation with the medium angular velocity duration threshold TMC2 or the low angular velocity duration threshold TMC3, but the medium angular velocity duration threshold TMC2 or the low angular velocity duration threshold T
It is set longer than MC3.

Next, referring to FIGS. 6, 7, 8, 9 and 11, the high angular velocity direction change determination processing of step S503,
The medium angular velocity direction change determination process in step S504, the low angular velocity direction change determination process in step S505, and the imaging direction change determination process without angular velocity in step S506 will be described.

FIG. 6 is a flowchart showing the high angular velocity direction change determination processing. First, it is determined whether or not the magnitude of the angular velocity is a high angular velocity (S601). When the magnitude of the angular velocity is a high angular velocity (S601; Yes),
In order to identify that the direction change due to the high angular velocity is detected, the high angular velocity direction change detection flag is set to ON (S6
02), the high angular velocity direction change determination processing is ended. on the other hand,
When the magnitude of the angular velocity is not the high angular velocity (S601; N
In (o), the high angular velocity direction change detection flag (G1 flag) is set to OFF in order to identify that the direction change due to the high angular velocity has not been detected (S602), and the high angular velocity direction change determination process ends.

FIG. 7 is a diagram showing a flowchart of the medium angular velocity direction change determination processing. First, it is determined whether the magnitude of the angular velocity is equal to or higher than the medium angular velocity (S701). When the magnitude of the angular velocity is equal to or higher than the medium angular velocity (S701; Ye
s) calculates the remaining time RTM2 of the medium angular velocity timer in order to determine whether the duration of the direction changing work at the medium angular velocity or higher is equal to or longer than the abnormality recognition duration time (S702),
It is determined whether or not the remaining time RTM2 of the medium angular velocity timer is zero (S703).

When the remaining time RTM2 of the medium angular velocity timer is zero (S703; Yes), the medium angular velocity direction change detection flag (G2 flag) is set to ON in order to identify that the direction change due to the medium angular velocity is detected. (S70
4) The middle angular velocity direction change determination process is ended. When the remaining time RTM2 of the medium angular velocity timer is not zero (S70
3; No) sets OFF to the medium angular velocity direction change detection flag to identify that the direction change due to the medium angular velocity has not been detected (S706), and ends the medium angular velocity direction change determination process.

On the other hand, if the magnitude of the angular velocity is not equal to or greater than the medium angular velocity (S701; No), the medium angular velocity duration threshold TMC2 is set as the initial value in the remaining time RTM2 of the medium angular velocity timer (S705), and the medium angular velocity is changed. In order to identify that no direction change has been detected, the medium angular velocity direction change detection flag is set to OFF (S706), and the medium angular velocity direction change determination process ends.

FIG. 8 is a flowchart showing the low angular velocity direction change determination processing. First, it is determined whether the magnitude of the angular velocity is equal to or higher than the low angular velocity (S801). When the magnitude of the angular velocity is equal to or higher than the low angular velocity (S801; Ye
s) calculates the remaining time RTM3 of the low angular velocity timer to determine whether or not the duration of the direction changing work at a low angular velocity or higher is equal to or longer than the abnormality recognition duration (S802),
It is determined whether the remaining time RTM3 of the low angular velocity timer is zero (S803).

When the remaining time RTM3 of the low angular velocity timer is zero (S803; Yes), the low angular velocity detection flag (g3 flag) is set to ON to identify that the direction change due to the low angular velocity is detected ( S804), the remaining time RTM4 of the image change timer for detecting the image change that determines whether the detection of the direction change due to the low angular velocity is the one detected by the change in the imaging direction of the surveillance camera or the one detected erroneously. Image change detection duration threshold TMC
4 is set as an initial value (S805), and the process proceeds to the next step S810 for determining an image change.

When the remaining time RTM3 of the low angular velocity timer is not zero (S803; No), the remaining time RTM4 of the image change timer is calculated to detect the image change (S80).
807), it is determined whether or not the remaining time RTM4 of the image change timer is zero (S808). When the remaining time RTM4 of the image change timer is zero (S808; Yes)
Determines that the change in direction due to the low angular velocity has not been detected, the low angular velocity detection flag is set to OFF (S809), and the process proceeds to the next step S810. When the remaining time RTM4 of the image change timer is not zero (S8
08; No) is the next step S8 for determining the image change.
Go to 10.

On the other hand, when the magnitude of the angular velocity is not equal to or higher than the low angular velocity (S801; No), the low angular velocity duration time threshold TMC3 is set as the initial value in the remaining time RTM3 of the low angular velocity timer (S806), and the image change is performed. The remaining time RTM4 of the image change timer is calculated for detection (S80
7) It is determined whether the remaining time RTM4 of the image change timer is zero (S808). When the remaining time RTM4 of the image change timer is zero (S808; Yes), it is determined that the change in direction due to the low angular velocity has not been detected, and the low angular velocity detection flag is set to OFF (S80).
9) and proceeds to the next step S810. When the remaining time RTM4 of the image change timer is not zero (S808; N
o), the process proceeds to the next step S810 for determining the image change.

Next, it is determined whether or not there is an image change (S810). That is, based on the monitoring area image change information calculated at the processing timing of this time and the monitoring area image change information of the change reference, the predetermined i blocks out of the n * m blocks are j or more blocks. It is determined whether or not the image has changed.

For example, it is determined whether or not there is an image change in 4 (= j) or more of predetermined 5 (= i) blocks among the 8 * 8 = 64 blocks. If there is an image change (S810; Yes), the image change detection flag (MD flag) is set to ON to identify that the image change is detected (S811), and the process proceeds to the next step S813. When there is no image change (S810; No), the image change detection flag is set to OFF to identify that the image change is not detected (S812), and the process proceeds to the next step S813.

Finally, it is determined whether or not the detection of the direction change due to the low angular velocity is detected by the change of the image pickup direction of the surveillance camera (S813), that is, the direction change due to the low angular velocity (g3 flag ON) and the image Change (MD flag ON)
Is detected, and if the detection of the direction change due to the low angular velocity is detected due to the change in the imaging direction of the surveillance camera (S813; Yes), it is determined that the direction change due to the low angular velocity is detected. Therefore, the low angular velocity direction change detection flag (G3 flag) is set to ON (S8
14) and the low angular velocity direction change determination process is ended.

On the other hand, if the detection of the direction change due to the low angular velocity is not detected by the change of the image pickup direction of the surveillance camera (S813; No), the low change is made to identify that the direction change due to the low angular velocity is not detected. The angular velocity direction change detection flag is set to OFF (S815), and the low angular velocity direction change determination process ends.

FIG. 11 is a diagram for explaining detection of an image change in detection of a direction change due to a low angular velocity. Here, a case where the image is divided into 8 * 8 = 64 blocks will be described as an example. In advance, a predetermined number (i) of blocks are selected in order to detect image changes. Here, a predetermined block is selected with a predetermined number of i = 5. In addition, the block to be selected is a block in which the distance from the surveillance camera is an image area of a distant part in the image, and blocks which are apart from each other by a predetermined distance are selected.

Whether the image change amount such as the edge amount or the histogram change amount in the selected block changes in the monitoring area image change information calculated at this processing timing and the change area monitoring area image change information. It is determined whether or not there is an image change when there are changes in j or more blocks. Here, for example, j = 4.

FIG. 9 is a diagram showing a flowchart of the image pickup direction change determination processing without angular velocity. First, it is determined whether there is an illuminance change based on the illuminance information measured at this processing timing and the illuminance information that is the change reference (S901). When there is no change in illuminance (S901; Y
es) determines whether or not there is an image change in order to determine whether or not a change in the imaging direction of the surveillance camera is detected without an angular velocity (S902).

That is, based on the monitoring area image change information calculated at the processing timing of this time and the monitoring area image change information of the change reference, k blocks for n * m blocks
By determining whether or not there is an image change in more than one block, it is determined whether or not a change in the imaging direction of the surveillance camera is detected. For example, for 8 * 8 = 64 blocks, it is determined whether or not there is an image change in 56 (= k) or more blocks.

When there is an image change (S902; Ye)
In s), the monitoring image change detection flag (G4 flag) is set to ON in order to identify that the change in the image pickup direction without angular velocity is detected (S903), and the image pickup direction change determination process without angular velocity is terminated. When there is no image change (S9
02; No), the monitoring image change detection flag is set to OFF in order to identify that the change in the image pickup direction without the angular velocity has not been detected (S904), and the image pickup direction change determination process without the angular velocity change ends.

On the other hand, when there is a change in illuminance (S901;
No), it is assumed that the image change is due to a change in illuminance, and the monitoring image change detection flag is set to OFF (S904) to identify that the change in the imaging direction without the angular velocity is not detected (S904). The imaging direction change determination process ends.

Further, the image-capturing-direction change determination method according to the present invention includes an image-capturing step for capturing an image of a monitoring area in a predetermined direction, and a change in the image-capturing direction in the image-capturing step by performing angular velocity information in a predetermined one direction or in a plurality of predetermined different directions. And a control step of detecting a change in the image capturing direction of the image capturing step based on the angular velocity information detected by the angular velocity detecting step and the monitoring area image information captured by the image capturing step. However, the image processing step of generating monitoring area image change information from the monitoring area image information imaged by the imaging step, and the angular velocity information detected by the angular velocity detection step continues at a low angular velocity or more for a predetermined low angular velocity duration threshold value or more. In addition, the monitoring area image change information generated by the image processing step is compared with the reference image change information and the predetermined change amount or more. And determining the direction change determining step and the imaging direction change case where, when the imaging direction change is determined by the direction change determining step, and an output step of outputting a detection of the image pickup direction changing.

Further, in the imaging direction change judging method of the present invention, the above-mentioned direction change judging step takes an image when the angular velocity information detected by the angular velocity detecting step continues at the middle angular velocity or more for the predetermined middle angular velocity duration time threshold value or more. Judge as a change of direction.

Further, in the image pickup direction change judging method according to the present invention, in the direction change judging step described above, when the angular velocity detected by the angular velocity detecting step is the high angular velocity information, it is decided that the image pickup direction is changed.

Further, the image pickup direction change judging method according to the present invention further comprises an illuminance detecting step of detecting illuminance information of the monitoring area, and in the above-mentioned direction changing judging step, the illuminance information detected by the illuminance detecting step greatly changes. If it is equal to or more than a predetermined reference illuminance value and the monitoring area image change information generated by the image processing step is equal to or more than a predetermined change amount that can be determined to be a large change compared with the reference image change information. In some cases, it is determined that the imaging direction has been changed.

Further, according to the present invention, it is also possible to record a program having the steps of the above-described image pickup direction change determination method on an information recording medium. Further, the information recording medium may be a compact disc, a flexible disc, a hard disc, a magneto-optical disc, a digital versatile disc, a magnetic tape, or a memory card.

[0068]

As described above, according to the present invention,
The following effects are achieved. The change of the image capturing direction due to the rotation of the surveillance camera is detected by the angular velocity information of the angular velocity information measured by the angular velocity sensor such as a gyro sensor, and the change in the image capturing direction is detected by the angular velocity information and the monitoring is performed by using the simple image processing. The change in the image capturing direction of the surveillance camera can be detected by organically combining the detection of the image change based on the monitoring region image change information obtained by converting the region image information into the predetermined image change amount.

[Brief description of drawings]

FIG. 1 is a diagram showing an overall configuration of a monitoring system.

FIG. 2 is a diagram showing a configuration of a surveillance camera.

FIG. 3 is an example of a configuration diagram showing functional blocks of a control unit of the surveillance camera.

FIG. 4 is an example of a diagram showing a flowchart of an imaging direction change detection process.

FIG. 5 is an example of a diagram showing a flowchart of direction change determination processing.

FIG. 6 is a diagram showing a flowchart of high angular velocity direction change determination processing.

FIG. 7 is a diagram showing a flowchart of a medium angular velocity direction change determination process.

FIG. 8 is a diagram showing a flowchart of low angular velocity direction change determination processing.

FIG. 9 is a diagram showing a flowchart of an imaging direction change determination process without angular velocity.

10A is a diagram showing the relationship between the magnitude of the angular velocity and the duration for changing the imaging direction of the surveillance camera; FIG.
[Fig. 4] is a diagram showing a threshold value of the magnitude of angular velocity, and (c) is a diagram showing a duration time for determining a change in the imaging direction.

FIG. 11 is a diagram illustrating detection of an image change in detection of a direction change due to a low angular velocity.

[Explanation of symbols]

100 Monitoring system 101, 101a, 101b, 101c, 101d
Monitoring camera 102 Controller 103 Monitor 104 Speaker 201 Control unit 202 Imaging unit 203 Illumination sensor 204 Gyro sensor 205 Storage unit 206 Communication unit 207 Monitor I / F 208 Display unit

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuo Ota             1410 Inada Stock Company, Hitachinaka City, Ibaraki Prefecture             Hitachi, Ltd. Digital Media Products Division             Within F-term (reference) 5C022 AA01 AB15 AB61 AB62 AB65                       AC26 AC69 CA00                 5C054 CA04 CC05 CE02 CE11 CF01                       EA01 EA05 EJ00 FA09 FC01                       FC11 FF02 HA18 HA19                 5C084 AA02 AA09 AA14 BB40 CC33                       DD12 GG78

Claims (4)

[Claims] 1. An image pickup unit for picking up an image of a monitoring area in a predetermined direction, and a change in the image pickup direction of the image pickup unit is detected as angular velocity information of a predetermined one direction or a plurality of predetermined different directions.
A single or a plurality of angular velocity sensors, and a control unit that detects a change in the image capturing direction of the image capturing unit based on the angular velocity information detected by the angular velocity sensor and the monitoring area image information captured by the image capturing unit. The control unit includes an image processing unit that generates monitoring region image change information from the monitoring region image information captured by the image capturing unit, and the angular velocity information detected by the angular velocity sensor has a predetermined low angular velocity or higher. Of the low angular velocity continuation time or more, and the case where the monitoring area image change information generated by the image processing means is a predetermined change amount or more as compared with the reference image change information, the image pickup direction is changed. The direction change determining means for determining and the detection of the image capturing direction change are output when the direction changing determiner determines the image capturing direction change. A surveillance camera device having an output means. 2. The direction change determination means determines that the imaging direction is changed when the angular velocity information detected by the angular velocity sensor continues at a medium angular velocity or higher for a predetermined medium angular velocity duration time threshold or longer. Surveillance camera equipment. 3. The surveillance camera device according to claim 1, wherein the direction change determining unit determines that the image capturing direction is changed when the angular velocity detected by the angular velocity sensor is high angular velocity information. 4. An illuminance sensor for detecting illuminance information of the monitoring area, wherein the direction change determination means does not significantly change the illuminance information detected by the illuminance sensor, and a predetermined reference illuminance value is obtained. If the above is the case and the monitoring area image change information generated by the image processing means is equal to or more than a predetermined change amount that can be determined to be a large change compared with the reference image change information, the imaging direction is changed. The surveillance camera device according to claim 1, wherein the surveillance camera device is determined to be.