JPH0721476A - Method and device for monitoring intrusion to restricted area - Google Patents

Abstract

PURPOSE:To highly accurately monitor the intrusion of an object into a restricted area by a camera. CONSTITUTION:An overall area 1A for a restricted area 1 and a foot area 1F corresponding to a floor part just under the section 1 are set up in a picture 20 of a monitored area including the floor. A part most close to the floor from the image body LA of an object image L in the picture 20 is extracted as an image foot part LF. At the time of detecting the simultaneous superposition of the image body LA and image foot part LF of the image L to respective areas 1A, 1F in the section 1, the intrusion of the object into the section 1 is judged. Preferably a side most close to the floor out of a circumscribed rectangle R circumscribed to the image L and having a side parallel with the floor in the monitored area is extracted from the image L as a rectangular foot part RF, and at the time of detecting the simultaneous superposition of the image body LA and the foot part RF of the object to respective areas 1A, 1F in the section 1, intrusion is judged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for monitoring intrusion of a prohibited area, and more particularly, in an image of a monitor screen display taken by a single camera of a monitored area having a prohibited area. The present invention relates to a method and an apparatus for monitoring intrusion of a prohibited area by a method of detecting an image of an object invading an image (hereinafter, also referred to as a prohibited area).

[0002]

2. Description of the Related Art Conventionally, a monitoring method has been performed in which a prohibited area is set on an image of a monitored area captured by a camera, and when a moving object image in the image overlaps with the prohibited area, there is an intrusion.
FIG. 2A shows the prohibited area 1 and the moving objects B1, B2, and B3 set in the image 20 of the entire monitored area. Prohibited area 1
An object B such as a human being provided around the dangerous substance 3 is a dangerous substance 3.
In order to prevent the object from approaching, the forbidden area 1 in the image 20 and the object B1, B2 or B3 are overlapped with each other to detect the entry into the forbidden area 1 and issue an alarm. FIG. 9 shows a configuration of a conventional prohibited area intrusion monitoring device including a prohibited area storage unit 38 for storing the prohibited area 1 and an overlap detection unit 39 for detecting an overlap between the image of the object B and the prohibited area 1.

[0003]

If the intrusion is determined by simply overlapping the images on the two-dimensional image obtained by one camera, there is a risk of erroneous determination. This is because the front-rear positional relationship in the camera depth direction is unknown. That is, FIG. 2 (A)
The moving object B1 or B2 has a portion overlapping the prohibited area 1, but it is highly likely that it does not enter the prohibited area 1 before or after the prohibited area 1. Therefore, there is a high possibility of erroneous detection when it is determined that the intrusion is due to a simple overlap of images. The virtual line 10 in FIG. 2 (A) is an auxiliary line for clarifying the mutual relationship between the zone 1 and the objects B1, B2, B3, etc. in the depth direction of the prohibited zone 1.

In order to avoid this erroneous detection, it is conceivable to monitor the foot of a moving object. Since many of the targets of ordinary intrusion monitoring are objects moving on the ground or floor such as humans, the foot portion in contact with the ground or the floor, for example, the foot F of the object B1 in FIG. 2 (B) and the floor area of the prohibited area. Using the overlap of the two as a criterion for the intrusion determination, the uncertainty of the mutual relation in the depth direction is to be eliminated. However, there is a problem in monitoring the feet. For example, the figure
As shown in 2 (B), if the prohibited area 1 is higher than the floor surface or at a position floating from the ground, it is impossible to set the floor area for the prohibited area 1, and it is necessary to monitor the feet. Intrusion cannot be detected only by itself. That is, even though the rod-shaped body integrated with the object B1 is in the prohibited area 1, the foot F does not enter the prohibited area 1, so that the intrusion cannot be detected. Further, when the foot F is outside the prohibited area 1 and the upper projection of the object B1 is in the prohibited area 1 like the object B1 in FIG. 2C, the intrusion of the upper projection is missed.

In order to solve the depth problem, one prohibited area 1 is monitored from different directions by using a plurality of cameras, and the logical product (AND) of the intrusion determination results of each camera is used as a criterion for the final determination. Can be considered. However, the use of multiple cameras not only causes an increase in the cost of the device itself, the need for additional work for installation and adjustment, an increase in the construction cost at the time of relocation, etc. It requires many cameras, and there are many problems such as the necessity of adjusting the installation position, angle of each camera, the mutual relation of the imaging field of view, etc. for each prohibited area.

Accordingly, it is an object of the present invention to provide a method and apparatus for highly accurately monitoring entry into a prohibited area with a single camera.

[0007]

Means for Solving the Problems Referring to the embodiments of FIGS. 1 (A) and 1 (B),
Image 20 of the monitored area including the floor, the entire area of prohibited area 1
1A and a foot area 1F corresponding to a floor portion immediately below the prohibited area are set, and a portion of the image body LA of the object image L in the image 20 closest to the floor of the monitored area is extracted as an image foot portion LF, and The image body LA and the image foot portion LF of the object image L are the prohibited areas 1 respectively.
The intrusion into the prohibited area 1 is monitored by detecting that the entire area 1A and the foot area 1F simultaneously overlap. Preferably, as shown in FIG. 1 (C), the side closest to the floor of the monitored area is extracted as a rectangular foot RF from a circumscribed rectangle R circumscribing the object image L and having a side parallel to the floor, and the object is the object. The image body LA and the rectangular foot part RF are the whole area 1A of the prohibited area 1, respectively.
Also, the intrusion is monitored by detecting the overlap with the foot area 1F at the same time.

Referring to FIGS. 1, 5 and 6, the forbidden area intrusion monitoring apparatus according to the present invention includes the forbidden area 1 in the image 20 of the monitored area including the floor as a whole area 1A and immediately below the forbidden area. Setting means to set as the foot area 1F equivalent to the floor part
16, an entire area storage means 22 and an underfoot area storage means 24 respectively storing the entire area 1A and the foot area 1F of the prohibited area 1, and an image for extracting the image body LA of the object image L by the change of the image 20 of the monitored area Body extraction means 26, image foot portion extraction means 28 for extracting the image foot portion LF closest to the floor of the monitored area of the image body LA, the image body LA of the object image and the entire area 1A of the prohibited area Main body weight detection means 30 for detecting overlap, foot overlap detection means 32 for detecting the overlap between the foot portion LF of the object image and the foot area 1F of the prohibited area, and the full weight detection means 30 and the foot overlap detection means 32
Intrusion determination means for determining intrusion by detecting simultaneous overlap with
It is equipped with 34.

[0009]

With reference to FIGS. 1 and 5, an image 20 of the monitored area including the floor is generated by the image input means 12 such as a camera, and a moving object L is moved by the moving object identification means 14 from the change of the image. (L1, L2, L3, etc. in FIG. 1A) are detected. The prohibited area 1 is set by the setting means 16 while watching the image 20 on the display means 18 such as a display. The moving object identifying means 14 and the setting means 16 for the prohibited area 1 belong to the prior art.

The operation of the present invention will be described with reference to the image 20 of FIG. 1, the block diagram of FIG. 6 and the flowchart of FIG. According to the present invention, in step 201 of FIG. 8, when setting the prohibited area 1 by the setting means 16, for example, as shown in FIG. 1 (A), the entire area 1A is set as the periphery of the prohibited area 1, and
A foot area 1F corresponding to the floor portion directly below the prohibited area 1 is also set. The whole area 1A and the foot area 1F are stored in the whole area storage means 22 and the foot area storage means 24, respectively. In step 202, the image body LA of the object L is extracted by the image body extracting means 26. The image body extracting unit 26 may be a device that attaches the labeling L to the image of the object L identified by the moving object identifying unit 14. The image foot portion extracting means 28 extracts the portion of the image of the object L closest to the floor of the image 20 as the image foot portion LF. FIGS. 1 (B) and (D) show image bodies LA1, LA2, LA3 and image foot portions LF1, LF2, LF3 for three objects L1, L2, L3.
Are shown respectively.

In step 203, the prohibited area whole area 1A in the whole area storage means 22 and the image body LA of the object to be extracted LA
It is detected whether or not there is an overlap with. In the case of FIG. 1 (D), the overlap with the entire area 1A is detected in arbitrary parts LP of the image bodies LA1 and LA3 of the objects L1 and L3, but the overlap is not detected in the image body LA2 of the object L2. In this case, an overlap is detected, so control proceeds to step 205. However, the entire area 1A of the prohibited area 1 and the image body LA of the extracted object
If no overlap is detected, the control proceeds to step 204, and the intrusion determination means 34 based on the information up to this point.
Determines that there is no intrusion.

In step 205, the foot area storage means 24
It is detected whether or not there is an overlap between the forbidden area 1F of the forbidden area inside and the image foot portion LF of the object to be extracted. In the case of FIG. 1 (D), the foot areas LF1 and LF2 are attached to the image foot parts LF1 and LF2 of the objects L1 and L2.
However, no overlap is detected at the image foot portion LF3 of the object L3. In this case, since the overlap with the foot area ARI 1F is detected, the control proceeds to step 206, in which the image body LA1 and the image foot portion LF1 of the object L1 are overlapped simultaneously with the entire prohibited area 1A and the foot area 1F, respectively. The intrusion determination means 34 determines that there is an intrusion based on the information. If necessary, enter an intruder as indicated by the shaded area in Fig. 1 (F).
The intrusion warning may be given to L1 by displaying red or flicker on the display means 18. Furthermore, the warning output means 36 can also issue a warning such as a siren. On the other hand, if no overlap is detected between the prohibited area foot area 1F and the image foot portion LF of the object to be extracted, the control proceeds to step 204, and the intrusion determination means 34 determines that there is no intrusion.

In step 207, it is judged whether or not it is necessary to continue monitoring,
If it is continued, the process returns to step 201, and if it is not continued, the process ends. In the case of continuing, if there is no change in the prohibited area 1, the process may return to step 202.

As is apparent from FIG. 1 (F), according to the present invention, the images of the prohibited area 1 and the object L3 are different from each other because of the positional shift in the camera depth direction with respect to the prohibited area 1 like the object L3. If there is no intrusion even if they overlap, it is judged that there is no intrusion, and even if the foot area 1F and the image foot LF2 of the forbidden area 1 overlap because they are vertically displaced from the forbidden area 1 like the object L2, they do not enter. Considers this as no intrusion, and the object
It is determined that there is an intrusion only when the image body LA1 and the image foot portion LF1 overlap at the same time as the entire area 1A and the foot area 1F of the prohibited area 1 like L1.

In this way, it is possible to achieve the provision of the "method and apparatus for highly accurately monitoring the intrusion into the prohibited area by one camera" which is the object of the present invention.

[0016]

EXAMPLES FIGS. 1 (C), 1 (E) and 7 show an example in which a circumscribed rectangle R is used for a moving object L. Steps in Figure 7
At 101, for example, the circumscribed rectangles R1, R2 and R3 having sides parallel to the floor of the monitored area and circumscribing the image bodies LA1, LA2 and LA3 of the objects L1, L2 and L3 of FIG. Ask as shown in E). As illustrated with respect to the circumscribing rectangle R1, the circumscribing rectangle R has coordinates of the upper left corner TL and the lower right corner BR (x ₁ ,
This can be uniquely determined by extracting y ₁ ), (x ₂ , y ₂ ). In step 102, the lowest coordinates of the circumscribed rectangle R, that is, the coordinates of the rectangular foot portion RF of the circumscribed rectangle R that corresponds to the side closest to the floor of the monitored area 1 is extracted. In this example,
The width of the rectangular foot portion RF in the horizontal direction, that is, the x direction is the upper left corner TL.
Is equal to the difference in x-coordinate between the lower right corner BR and the lower right corner BR (x ₁ -x ₂ ), and the thickness of the rectangular foot portion RF, that is, the width in the y direction is m (0 ≦ m <(y ₁ -y ₂ )).
Is. In order to avoid an error in the overlap between the prohibited area foot area 1F and the rectangular foot portion RF, it is desirable that the thickness m is not so large. In step 103, the rectangular foot RF
Image is formed like RF1, RF2 and RF3 in FIG. 1 (E).
In this embodiment, the presence or absence of the intrusion is determined by the overlap between the image body LA of the object L and the entire area 1A of the prohibited area 1 and the overlap of the rectangular foot RF of the object L and the foot area 1F of the prohibited area 1 at the same time. To do.

If the rectangular foot portion RF is used, as shown in FIG. 3, the object L is a human and its foot is a prohibited area Foot area 1F
When the hand is outside the area and only the hand is within the entire area 1A of the prohibited area 1, it is possible to detect the invasion of the hand into the prohibited area 1.

FIG. 4 shows a plurality of whole areas 1A1, 1A2, 1A3, etc. in the prohibited area 1 in the monitored area image and a plurality of foot areas 1F1, 1F2, 1F3 corresponding to the floor portion directly under each whole area.
The following shows an example in which In this case, the corresponding whole area and the foot area are paired. That is, the entire area 1A1 and the foot area 1F1 are paired, and similarly, 1A2 and 1F2 are paired, and 1
A3 and 1F3 are paired. The intrusion determining means 34 monitors the intrusion into the prohibited area by detecting that the image body LA and the image foot portion LF of the object image L simultaneously overlap the same pair of the entire area 1Ai and the foot area 1Fi in the prohibited area, respectively. To do. By dividing the prohibited area 1 into a plurality of areas, it is possible to avoid an error due to the height of the object L in the intrusion monitoring of the prohibited area and improve the accuracy of the intrusion determination.

[0019]

As described above in detail, the method and apparatus for monitoring the intrusion of the prohibited area according to the present invention determines whether or not the image body and the image foot portion of the object image simultaneously overlap the entire area and the foot area of the prohibited area, respectively. As a criterion, the following remarkable effects are obtained.

(B) Even if the image of the object outside the prohibited area overlaps with the prohibited area area on the screen, the positional relationship in the depth direction taken by the camera is accurately determined, and this is erroneously detected as an entry into the prohibited area. There is no. (B) Since the vertical positional relationship is accurately determined and the prohibited area floating from the floor is considered not only the overlap of the foot area only, but also the overlap of the entire area and the image body, the prohibited area is considered. It is possible to avoid erroneous intrusion detection for an object lower than the lower end surface of the. (C) It is possible to use a rectangular foot part that circumscribes the object and has a side parallel to the floor of the monitored area, and even if only the part protruding from the object enters the prohibited area Can be accurately detected. (D) Since three-dimensional monitoring is performed with only one camera, it is easy to install, move, and adjust the intrusion monitoring device in the prohibited area. (E) Since it does not require a plurality of cameras, it can be implemented at low cost.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing the principle of the present invention.

FIG. 2 is an explanatory diagram of a conventional technique.

FIG. 3 is an explanatory diagram of an embodiment using a rectangular foot portion.

FIG. 4 is an explanatory diagram of a prohibited area including a plurality of parts.

FIG. 5 is a block diagram of a basic configuration of an intrusion monitoring device.

FIG. 6 is a block diagram of an essential part of an embodiment of the device of the present invention.

FIG. 7 is a flow chart of rectangular foot extraction.

FIG. 8 is a flow chart of the operation of the device of the present invention.

FIG. 9 is an example of a principal block diagram of a conventional technique.

[Explanation of symbols]

1 prohibited area 1A whole area
1F Foot area 3 Dangerous goods 10 Virtual line
12 Image input means 14 Moving object identification means 16 Setting means
18 Display means 20 Image of monitored area 22 Whole area storage means
24 Foot area storage means 26 Image body extraction means 28 Image foot portion extraction means
30 Weight detection means 32 Foot overlap detection means 34 Intrusion determination means
36 Alarm means 38 Prohibited area storage means 39 Overlap detection means
L object image LA image body LF image Foot part
Any part of the LP object image.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Jinichi Kikuchi 3-20-8 Narita Nishi, Suginami-ku, Tokyo Okura Electric Co., Ltd. (72) Inventor Yutaka Maeda 3-20-8 Narita-nishi, Suginami-ku, Tokyo No. Okura Electric Co., Ltd.

Claims (5)

[Claims] 1. An entire area of a prohibited area and a foot area corresponding to a floor portion directly below the prohibited area are set in an image of the monitored area including a floor, and the monitored area of the image body of the object image in the image is monitored. The portion closest to the floor of the object is extracted as an image foot portion, and the intrusion into the prohibited area is monitored by detecting that the image body and the image foot portion of the object image overlap with the entire prohibited area and the foot area, respectively. Intrusion monitoring method for prohibited areas. 2. The intrusion monitoring method according to claim 1, wherein a side closest to the floor of the monitored area is extracted as a rectangular foot portion from a circumscribed rectangle having a side circumscribing the object image and parallel to the floor, and the object image The intrusion monitoring method of the prohibited area, which comprises monitoring the intrusion by detecting that the image body and the rectangular foot portion simultaneously overlap the entire area and the foot area of the prohibited area. 3. The intrusion monitoring method according to claim 1, wherein a plurality of whole areas are set in a prohibited area in the image of the monitored area, and the whole area is paired with the whole area directly below the whole area. The foot area is set, and the intrusion into the prohibited area is monitored by detecting that the image main body and the image foot portion of the object image are simultaneously overlapped with an arbitrary entire area in the prohibited area and the foot area paired with the entire area. Intrusion monitoring method for prohibited areas. 4. Setting means for setting a prohibited area as an entire area and a foot area corresponding to a floor portion immediately below the prohibited area in an image of a monitored area including a floor, and the entire area and the foot area of the prohibited area are stored respectively. Whole area storage means and foot area storage means, an object image is extracted as an image main body by a change in the image of the monitored area, and a portion of the object image closest to the floor of the monitored area is extracted as an image foot portion. Means, main body weight detection means for detecting an overlap between the image body of the object image and the entire prohibited area, and foot overlap detection means for detecting an overlap between the image foot portion of the object image and the foot area of the prohibited area And an intrusion monitoring device in a prohibited area, comprising intrusion determination means for determining intrusion by simultaneous detection of the main body weight detection means and the foot overlap detection means. 5. The intrusion monitoring device according to claim 4, wherein a circumscribing rectangle having a side circumscribing the object image and parallel to the floor is set by the extracting means, and the side of the circumscribing rectangle closest to the floor is a rectangular foot. An intrusion monitoring device for a prohibited area, which is extracted as a section, and the overlap between the rectangular foot portion and the foot area of the prohibited area is detected by the foot overlap detection means.