JP2013131178A - Obstacle alarm device - Google Patents

Abstract

An obstacle alarm device that can clearly indicate to a driver the presence of an obstacle approaching a vehicle, in particular the approaching direction of the obstacle, without making it difficult to see the situation around the vehicle.
An obstacle alarm device 100 includes a noticed photographed image generation unit that creates a noticed photographed image based on a photographed image G, an object presence determination part that determines whether or not an object 7 exists in an outer region O, and the like. A moving direction determining unit that determines the moving direction of the object 7 in the outer region O, a mask region setting unit that sets a mask region M to be displayed superimposed on the scene behind the vehicle 1 in the target photographed image, and a predetermined region An obstacle existence area generation unit that generates a plurality of obstacle existence areas B corresponding to a plurality of areas divided for each area in the mask area M, and the object 7 in the outer area O by the moving direction determination unit And an explicit image output unit that highlights the obstacle existence area B corresponding to the area where the object 7 is present.
[Selection] Figure 2

Description

  The present invention relates to an obstacle alarm device that clearly indicates to an occupant the presence of an obstacle approaching a vehicle.

  There are blind spots around the vehicle that cannot be seen from the position of the driver, and the driver needs to pay close attention to the periphery of the vehicle when driving the vehicle. In particular, when the vehicle is moved backward and parked, there are many users who are not good at parking itself, and there is not a lot of mental fatigue. Thus, conventionally, techniques for monitoring obstacles around the vehicle have been used (for example, Patent Documents 1 and 2).

  The vehicle obstacle alarm device described in Patent Document 1 includes a lateral movement obstacle detection means, a lateral movement direction detection means, and a lateral movement information provision means. The laterally moving obstacle detection means detects an obstacle that moves in the direction crossing the traveling direction in front of the vehicle. The lateral movement direction detection means detects the lateral movement direction of the obstacle detected by the lateral movement obstacle detection means. The lateral movement information providing means provides the driver with information regarding the lateral movement direction of the obstacle detected by the lateral movement direction detecting means. At this time, the lateral movement information providing means displays an arrow indicating the lateral movement direction detected by the lateral movement direction detecting means on the display unit.

  The vehicle surrounding monitoring apparatus described in Patent Document 2 includes an imaging unit, an obstacle detection unit, and a display unit. The imaging means images the surroundings of the vehicle including a part of the host vehicle. The obstacle detection means detects an obstacle located around the vehicle and calculates a distance between the detected obstacle and the host vehicle. The display unit displays the captured image captured by the imaging unit and the obstacle display image indicating the distance calculated by the obstacle detection unit on one screen.

Japanese Patent Application Laid-Open No. 11-115660 JP 2009-217740 A

  Obstacles around the vehicle are detected by detecting obstacles around the vehicle as in the techniques described in Patent Literature 1 and Patent Literature 2 and displaying information (arrows, etc.) clearly indicating the obstacles on the screen. Can be notified. However, the screen size of the display (display means) mounted on the vehicle is not large. For this reason, if an arrow or the like is displayed on the image showing the situation around the vehicle displayed on the display, the situation around the vehicle may become difficult to see or an obstacle may not be grasped.

  In view of the above problems, an object of the present invention is to make it possible to clearly indicate the presence of an obstacle approaching the vehicle, in particular, the approaching direction of the obstacle, to the driver without making it difficult to see the situation around the vehicle. It is to provide an alarm device.

In order to achieve the above object, the characteristic configuration of the obstacle alarm device according to the present invention is as follows:
A captured image acquisition unit that acquires a captured image of a scene behind the vehicle;
An attention-captured image generation unit that generates an attention-captured image based on the captured image;
An object presence determination unit that determines whether or not an object exists in an outer region outside the target captured image;
A moving direction determination unit that determines the moving direction of the object in the outer region;
A mask area setting unit for setting a mask area to be superimposed and displayed on a scene behind the vehicle, out of the noted photographed image;
Obstacle presence area generation unit that generates a plurality of obstacle existence areas corresponding to a plurality of areas divided into predetermined areas when looking at the rear of the vehicle from the inside of the vehicle,
An explicit image output unit that highlights an obstacle existing area corresponding to a region where the object exists when the movement direction determination unit determines that the object in the outer region moves to the center side of the target captured image; ,
It is in the point equipped with.

  With such a characteristic configuration, it is possible to clearly indicate the presence of an object existing around the vehicle to the occupant while displaying the situation around the vehicle. Therefore, even when the screen size of the monitor is small, an object around the vehicle is not missed. In addition, since the obstacle existing area is highlighted and displayed, it is easy for the passenger to understand intuitively. Therefore, it is possible to clearly indicate to the occupant the presence of an object approaching the vehicle without missing an object around the vehicle.

In addition, the obstacle presence area is arranged at the top of the display screen,
It is preferable that the explicit image output unit displays the corresponding obstacle existence area extending downward when the object enters the target captured image.

  Generally, the sky appears at the top of the display screen. Therefore, when the obstacle existence area is arranged at the upper part of the display screen, it is possible to prevent the scene around the vehicle from being hidden.

  Further, it is preferable that the explicit image output unit blinks the corresponding obstacle existence area when the object is present in an area including a position directly behind the vehicle.

  With such a configuration, it is easy to intuitively recognize a region corresponding to the highlighted obstacle existence area. Therefore, the presence of an object approaching the vehicle can be appropriately specified.

  The obstacle existence area is preferably displayed when it is determined that an object is present around the vehicle.

  With such a configuration, it is possible to clearly indicate that an object is approaching the vehicle when the obstacle presence area is displayed in the mask area. Therefore, the approach of the object can be clearly indicated even before the obstacle existing area is colored.

  Further, it is preferable that the explicit image output unit colors the obstacle existing area as the highlighted display.

  With such a configuration, the obstacle presence area corresponding to the area where the object is present is colored, so that the approach of the object can be clearly indicated to the vehicle occupant.

It is the block diagram which showed typically the structure of the obstacle alarm device. It is the figure which showed an example of the process of an obstacle alarm device. It is the figure which showed an example of the synthesized image. It is the figure which showed an example of the synthesized image. It is the figure which showed an example of the synthesized image. It is the figure which showed an example of the synthesized image. It is the figure which showed an example of the synthesized image. It is the figure which showed an example of the synthesized image. It is the figure which showed typically the process of the obstacle alarm device.

  Hereinafter, embodiments of the present invention will be described in detail. The obstacle alarm device 100 according to the present invention has a function of clearly indicating that an object is approaching the driver of the vehicle when there is an object approaching the vehicle. Hereinafter, it demonstrates using drawing.

  FIG. 1 is a block diagram schematically showing the configuration of the obstacle alarm device 100. As shown in FIG. 1, the obstacle alarm device 100 includes a captured image acquisition unit 11, a focused captured image generation unit 12, an outer region generation unit 13, an object presence determination unit 14, a movement direction determination unit 15, and an explicit image output unit. 16, an explicit image storage unit 17, a composite image generation unit 18, a mask area setting unit 19, and an obstacle presence area generation unit 20. Each functional unit includes the above-described functional units for performing various processes for clearly indicating the approach of the object 7 to the driver of the vehicle 1 by using a CPU as a core member.

  The captured image acquisition unit 11 acquires a captured image G obtained by capturing a scene behind the vehicle 1. Here, the vehicle 1 is provided with a camera 5. The camera 5 according to the present embodiment includes a digital camera that incorporates an image sensor such as a charge coupled device (CCD) or a CMOS image sensor (CIS) and outputs captured information as moving image information. As shown in FIG. 2A, such a camera 5 is located behind the vehicle 1 in the vicinity of the license plate provided at the outer rear part of the vehicle 1 or in the vicinity of the emblem provided at the outer rear part of the vehicle 1. It is arrange | positioned with a slight depression angle toward. The camera 5 includes a wide-angle lens (not shown). Thereby, the scene around the vehicle 1 can be photographed over the rear of the vehicle 1 over approximately 180 degrees. Such an imaging range is shown as “wide viewing angle” in FIG. The camera 5 has a performance of outputting a moving image as a captured image G in real time. Such a captured image G is transmitted to the captured image acquisition unit 11.

  An example of such a captured image G is shown in FIG. The full width of FIG. 2 (b) corresponds to the wide viewing angle of FIG. 2 (a). Here, in the photographed image G, the object 7 on the left side as viewed from the rear of the vehicle 1 as shown in FIG. 2A is on the right side in the photographed image G as shown in FIG. Thus, mirror image processing is performed. This is because when the scene behind the vehicle 1 is displayed on the monitor 50, it is easy for the driver of the vehicle 1 to intuitively understand whether the object 7 included in the captured image G is on the left side or the right side of the vehicle 1. It is to do.

  Returning to FIG. 1, the noticeable photographed image generation unit 12 generates a noticeable photographed image based on the photographed image G. In the present embodiment, the shooting range of the shot image G is a wide viewing angle. For this reason, the noticeable photographed image generation unit 12 generates a narrow-field region N that is a central portion of the photographed image G as the noticeable photographed image. The captured image G is transmitted from the captured image acquisition unit 11 described above. In the present embodiment, the noticeable photographed image corresponds to the central portion in the horizontal direction of the photographed image G shown in FIG. Such a narrow visual field region N is preferably a region, for example, about 120 to 130 degrees behind the vehicle 1 like the “narrow visual field angle” in FIG. In addition, since the narrow-field region N is close to the advanceable range when the vehicle 1 moves backward, it is referred to as a “focused captured image” because it is a region that should be particularly noted in the captured image G. Such a noticeable photographed image corresponds to a display image displayed on the monitor 50 described later (see FIG. 2C). In the present embodiment, the “focused captured image” is described as an image of a “narrow field of view”.

  The outer area generation unit 13 generates an outer area O outside the target captured image. That is, an outer region O outside the narrow field region N in the captured image G is generated. As described above, the narrow-field region N is generated by the noticeable captured image generation unit 12 at the central portion in the horizontal direction of the captured image G. The outer region generation unit 13 generates an outer region O as shown in FIG. 2B outside the narrow visual field region N in the lateral direction. The outer region O generated by the outer region generation unit 13 is transmitted to an object presence determination unit 14 described later.

  The object presence determination unit 14 determines whether or not the object 7 exists in the outer region O. The outer region O is transmitted from the outer region generator 13. Whether or not the object 7 exists can be determined using a known image recognition process such as pattern matching. Of course, it is possible to determine whether or not the object 7 exists in the outer region O by processing other than pattern matching. The determination result of the object presence determination unit 14 is transmitted to a movement direction determination unit 15 described later.

  The movement direction determination unit 15 determines the movement direction of the object 7 in the outer region O. Such determination of the moving direction is performed when the object presence determination unit 14 determines that the object 7 exists in the outer region O. In particular, in this embodiment, the moving direction determination unit 15 determines whether or not the object 7 in the outer region O moves toward the narrow visual field region N. The movement toward the narrow visual field N indicates that the vehicle 1 moves from the outer side in the width direction of the vehicle 1 to the direction just behind the vehicle 1 behind the vehicle 1. Such a determination can be performed by comparing the position of the object 7 in the current captured image G with the position of the object 7 in the captured image G a predetermined time ago, for example, or by using an optical flow. It is possible to use this method. Such a determination result of the moving direction is transmitted to the explicit image output unit 16 described later.

  The mask area setting unit 19 sets a mask area M to be superimposed and displayed on the scene behind the vehicle 1 in the target photographed image. Thereby, at least a part of the scene behind the vehicle 1 is hidden. In the present embodiment, as shown in FIG. 2C, the mask area M is set at the upper part of the screen, that is, the upper part in the target captured image. This mask area M is formed across both sides of the target image. The mask area M is colored, for example, in black so that the scene above the vehicle 1 cannot be seen. Of course, other colors may be used. Note that the mask region M may be filled and superimposed on the scene behind the vehicle 1 or may be translucent and displayed superimposed on the scene behind the vehicle 1.

  The obstacle existence area generation unit 20 generates a plurality of obstacle existence areas B corresponding to a plurality of areas divided into predetermined areas in the mask area M. The predetermined area is an area obtained by dividing the display screen of the monitor 50. In this embodiment, the area including the rear of the vehicle 1 and the areas on the left and right sides of the area correspond to each other. The obstacle existence area generation unit 20 generates an obstacle existence area B composed of a plurality of obstacle existence areas b1-b3 including such areas in the mask area M. In the present embodiment, as described above, the mask region M is disposed at the upper part of the screen. Therefore, the obstacle existence area B is also arranged at the upper part of the monitor 50.

  Specifically, the obstacle existence area B includes an obstacle existence area b1 on the left rear side of the vehicle 1 when the vehicle 1 is viewed from the rear, an obstacle existence area b2 corresponding to the rear of the vehicle 1, and the right side of the vehicle 1 It consists of a rear obstacle presence area b3. In the present embodiment, the obstacle existence area B does not include an area corresponding to the outer area O.

  The explicit image output unit 16 waits for the outline of the target captured image from entering the target captured image after the movement direction determination unit 15 determines that the object 7 in the outer region O moves to the center side of the target captured image. A frame index W having a small outer shape is displayed. Here, in the present embodiment, the attention-captured image corresponds to an image in the narrow visual field N. After the detection of the object 7 in the outer region O, the object presence determination unit 14 and the movement direction determination unit 15 can detect until the object 7 enters the target captured image. The frame index W having an outer shape smaller than the contour of the noticeable photographed image means that the frame index W is at least smaller than the noticeable photographed image. Therefore, the explicit image output unit 16 detects the movement of the object 7 in the outer region O toward the center side of the narrow field region N until it enters the narrow field region N of the vehicle 1. A frame index W is displayed in the display screen.

  Specifically, when the object 7 moves to the center of the narrow field area N behind the vehicle 1 by the movement direction determination unit 15, the frame index W is set until the object 7 enters the narrow field area N. Display blinking. This blinking display stops when the object 7 enters the narrow field area N. As a result, the passenger of the vehicle 1 can intuitively recognize the presence of the object 7 approaching the vehicle 1. Such a frame index W is stored in the explicit image storage unit 17 as an explicit image as shown in FIG.

  In addition, when the object 7 enters the target captured image, the explicit image output unit 16 performs a display in which the frame index W is absorbed in the obstacle existing area B corresponding to the area on the side on which the object 7 enters. The obstacle existing area B corresponding to the area where the object 7 enters corresponds to the obstacle existing area b1 when the object 7 exists in the left outer area O, and the object 7 in the right outer area O. Is present, the obstacle existing area b3 is equivalent. On the other hand, as described above, when the object 7 existing in the outer region O is detected, the frame index W is displayed blinking. At this time, whether the object 7 is in the right outer region O or the left outer region O is known by the object presence determination unit 14. Therefore, when the object 7 existing in the left outer region O enters the narrow field region N, the explicit image output unit 16 performs display in which the frame index W is absorbed by the obstacle existing area b1, and the right outer region When the object 7 existing in the region O enters the narrow visual field region N, display is performed in which the frame index W is absorbed in the obstacle existing area b3.

  The explicit image output unit 16 performs such display. Here, in the present embodiment, the obstacle existence area B and the frame index W are combined with the captured image of interest which is the narrow visual field N and displayed on the monitor 50. Therefore, the composite image generation unit 18 generates a composite image in which the obstacle existence area B and the frame index W are combined with the target captured image.

  Thus, by performing blinking display of the frame index W and absorption display of the frame index W to the obstacle existing area B on the side of the object 7 entering the narrow field of view N, the vehicle 1 is informed to the occupant of the vehicle 1 It is possible to visually indicate that the object 7 is close to 1 and that the object 7 enters the narrow visual field N.

  Thereafter, the explicit image output unit 16 highlights the obstacle existence area B corresponding to the area where the object 7 exists. In the present embodiment, coloring is used as such highlighting. Further, as described above, the frame index W is absorbed in the obstacle existing area B on the side where the object 7 enters. Therefore, the explicit image output unit 16 colors the obstacle existing area B in which the frame index W is absorbed. Such coloring is preferably red, for example, so as to be visually noticeable. Of course, it is possible to color with other colors.

  Thereafter, when the object 7 enters the noticeable captured image, the explicit image output unit 16 extends the corresponding obstacle existence area B downward and displays it. The corresponding obstacle existence area B is the obstacle existence area B in which the frame index W is absorbed and colored. To extend downward means to extend a colored region from the upper part of the screen where the obstacle existence area B is arranged toward the lower part of the screen. As described above, when the object 7 enters the noticeable captured image, the explicit image output unit 16 extends the colored obstacle existing area B downward to enlarge the colored region. Therefore, since the colored area becomes large, it becomes easier for the occupant to catch the eye, and it is possible to increase alerting to the entry of the object 7 into the noticeable photographed image. Note that such downward display may be extended to the lower end of the display screen, or may be stopped until the middle of the display screen.

  When the object 7 enters the noticed photographed image and exists in a region including the rear side (rear) of the vehicle 1, the explicit image output unit 16 displays the obstacle existence area b <b> 2 corresponding to the region including the rear side of the vehicle 1. Display blinking. During lighting in the blinking display, the host vehicle image CI including a part of the rear of the vehicle 1 may be displayed in the obstacle existence area b2. On the other hand, the obstacle existence area b2 may be completely eliminated while the blinking display is extinguished so that the noticeable captured image can be visually recognized as it is. The explicit image output unit 16 repeatedly performs such blinking display until the object 7 leaves the area including the rear of the vehicle 1 corresponding to the obstacle existing area b2.

  When the object 7 moves from an area including the rear of the vehicle 1 corresponding to the obstacle existing area b2 to the area adjacent to the object 7, the explicit image output unit 16 colors the corresponding obstacle existing area b1. Thereafter, the obstacle existence area b1 is extended downward and displayed until the object 7 leaves the noticeable photographed image. Therefore, as in the case where the object 7 enters the noticeable photographed image, the colored area becomes large, so that it becomes easier for the passenger to catch the eye and raises the alert for the entry of the object 7 into the noticeable photographed image. be able to. Note that such downward display may be extended to the lower end of the display screen, or may be stopped until the middle of the display screen. Such an image related to the highlighted display of the obstacle existence area B is also stored in the explicit image storage unit 17 as shown in FIG.

  The explicit image output unit 16 stops the coloring or the downward extension of the obstacle existing area b1 when the object 7 leaves the noticeable photographed image. As a result, the occupant can grasp that the object 7 has left the noticeable captured image.

  An example of a series of images relating to the display of the frame index W, the coloring of the obstacle presence area B, and the downward extension is shown in FIGS. In particular, FIGS. 3 to 5 show a series of images from the display of the frame index W to absorption, and FIGS. 6 to 8 show the coloring and the like of the obstacle existing area B.

  As shown in FIG. 3A, the obstacle existence area B is synthesized and displayed in the noticeable photographed image. When the object 7 moving from the outer area O to the center of the narrow field area N is detected, the frame index W is synthesized and displayed (FIG. 3B). The frame index W is displayed blinking by repeating FIGS. 3B and 3C a predetermined number of times.

  When the object 7 in the outer region O moves to the center side of the narrow field region N, the frame index W is displayed so as to be absorbed by the obstacle existing area B on the side on which the object 7 enters (FIG. 3D). -Fig. 5 (c)). In the present embodiment, an example in which the object 7 enters from the right outer region O toward the vehicle rear center side is given. Therefore, the frame index W is absorbed in the obstacle presence area b3.

  As shown in FIG. 5C, when the frame index W is absorbed by the obstacle existence area b3, the obstacle existence area b3 is colored (FIG. 6A). Thereafter, until the object 7 leaves the area corresponding to the obstacle existing area b3, the obstacle existing area b3 is extended downward while being colored (FIG. 6B-FIG. 6E).

  When the object 7 moves to an area including the rear (back) of the vehicle 1, the obstacle existence area b2 corresponding to the area is displayed in a blinking manner (FIGS. 6E to 7E). When the object 7 moves from an area including the back of the vehicle 1 corresponding to the obstacle existence area b2 to an area adjacent to the object 7, the obstacle existence area b1 is colored and displayed extending downward. (FIGS. 8A to 8D). After that, when the object 7 leaves the noticeable photographed image, the coloring and extension are stopped (FIG. 8 (e)).

  Next, a series of processes in which the obstacle alarm device 100 displays an image in which the obstacle existence area B is highlighted on the monitor 50 will be described with reference to the schematic diagram of FIG. First, the captured image acquisition unit 11 acquires a captured image G captured by the camera 5 of the vehicle 1 (step # 1).

  Next, the noticeable photographed image generation unit 12 generates the central part of the acquired photographed image G as the noticeable photographed image (step # 2). On the other hand, the outer area generation unit 13 generates both lateral portions of the acquired captured image G as the outer area O (step # 3). Whether or not the object 7 is present in the outer region O generated in this way is determined by the object presence determination unit 14 (step # 4).

  If it is determined that the object 7 exists in the outer region O, the moving direction determination unit 15 determines the moving direction of the object 7 (step # 5). When the object 7 enters the target photographed image from the outer region O, the explicit image output unit 16 outputs an explicit image (step # 6). This explicit image is output with reference to the explicit image stored in the explicit image storage unit 17.

  The composite image generation unit 18 generates a composite image by superimposing the explicit image output in Step # 6 on the noticeable captured image generated in Step # 2 (Step # 7). The generated composite image is displayed on the monitor 50 (step # 8). In this way, when the object 7 enters the noticed photographed image, the obstacle existing area B is displayed so as to be colored so that the passenger of the vehicle 1 clearly indicates that the object 7 has entered the noticed photographed image in the vehicle 1. It becomes possible. Further, since the obstacle existence area B on the side where the object 7 enters the narrow visual field N is colored, the occupant can intuitively recognize the direction in which the object 7 enters. Thus, according to the obstacle alarm device 100, it is possible to clearly indicate that an obstacle is approaching the vehicle 1 and to clearly indicate the approach direction.

  As described above, according to the obstacle alarm device 100 according to the present invention, even if the object 7 is not shown in the screen of the monitor 50 provided in the vehicle 1, the object 7 approaching the vehicle 1 enters the noticeable captured image. When displaying, the frame index W is displayed and the object 7 is displayed so as to be absorbed by the obstacle existence area B on the side where the object 7 enters, so the presence and direction of the object 7 approaching the vehicle 1 are clearly indicated to the occupant. be able to. Therefore, even when the screen size of the monitor 50 is small, the object 7 approaching the vehicle 1 is not missed.

[Other Embodiments]
In the above embodiment, it has been described that the frame index W is absorbed in the obstacle existence area B corresponding to the region on the side on which the object 7 enters when the object 7 enters the target captured image. However, the scope of application of the present invention is not limited to this. Of course, the frame index W may not be absorbed in the obstacle presence area B but may be displayed in a form where the display is stopped when the object 7 enters the target captured image.

  In the embodiment described above, the frame index W is displayed or the explicit image in which the frame index W is absorbed is displayed when the object 7 enters the target captured image. However, the scope of application of the present invention is not limited to this. Of course, it is possible to adopt a configuration in which the display of the frame index W is not performed.

  In the above embodiment, the obstacle existence area B has been described as being arranged at the top of the screen. However, the scope of application of the present invention is not limited to this. Obstacle presence area B can naturally be configured to be displayed when it is determined that the object 7 exists around the vehicle 1. In such a case, the obstacle presence area B can be displayed based on the determination result of the object presence determination unit 14.

  In the above-described embodiment, the obstacle existence area B is arranged on the upper part of the monitor 50, and the explicit image output unit 16 moves down the corresponding obstacle existence area B when the object 7 enters the target photographed image. It was explained that it was extended to display. However, the scope of application of the present invention is not limited to this. Of course, it is possible to configure such that the corresponding obstacle existence area B described above is not extended and displayed.

  In the above-described embodiment, the explicit image output unit 16 has been described as blinking the corresponding obstacle existence area b <b> 2 when the object 7 exists in an area including the rear of the vehicle 1. However, the scope of application of the present invention is not limited to this. The explicit image output unit 16 can naturally be configured not to blink the corresponding obstacle existence area b2.

  In the above-described embodiment, it has been described that coloring is performed as the highlight display. However, the scope of application of the present invention is not limited to this. As another highlight display, for example, the target obstacle existence area B can be blinked as a matter of course. Furthermore, other highlighting can naturally be applied.

  The present invention can be used for an obstacle warning device that clearly indicates the presence of an obstacle approaching a vehicle to an occupant.

DESCRIPTION OF SYMBOLS 1: Vehicle 7: Object 11: Photographed image acquisition part 12: Attention photographed image generation part 14: Object presence determination part 15: Movement direction determination part 16: Explicit image output part 19: Mask area setting part 20: Obstacle presence area generation Part 100: Obstacle alarm device B (b1-b3): Obstacle presence area G: Captured image M: Mask area O: Outside area

Claims (5)

A captured image acquisition unit that acquires a captured image of a scene behind the vehicle;
An attention-captured image generation unit that generates an attention-captured image based on the captured image;
An object presence determination unit that determines whether or not an object exists in an outer region outside the target captured image;
A moving direction determination unit that determines the moving direction of the object in the outer region;
A mask area setting unit for setting a mask area to be superimposed and displayed on a scene behind the vehicle, out of the noted photographed image;
Obstacle presence area generation unit that generates a plurality of obstacle existence areas corresponding to a plurality of areas divided into predetermined areas when looking at the rear of the vehicle from the inside of the vehicle,
An explicit image output unit that highlights an obstacle existing area corresponding to a region where the object exists when the movement direction determination unit determines that the object in the outer region moves to the center side of the target captured image; ,
Obstacle alarm device comprising: The obstacle presence area is arranged at the top of the display screen,
2. The obstacle alarm device according to claim 1, wherein the explicit image output unit displays the corresponding obstacle existence area extending downward when the object enters the target photographed image.   3. The obstacle alarm device according to claim 1, wherein the explicit image output unit blinks the corresponding obstacle existence area when the object is present in an area including right behind the vehicle.   The obstacle obstacle device according to any one of claims 1 to 3, wherein the obstacle existence area is displayed when it is determined that an object is present around the vehicle.   The obstacle alarm device according to any one of claims 1 to 4, wherein the explicit image output unit colors the obstacle existing area as the highlighted display.

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