JP2013168063A - Image processing device, image display system, and image processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology that allows a driver to make an appropriate decision to change a lane.SOLUTION: An image acquisition unit 21 acquires a photographing image of a camera 5 mounted on an own vehicle 9, and an image generation unit 22 generates a surrounding image indicative of a surrounding area of the own vehicle 9 including an area shown on a side mirror of the own vehicle 9 on the basis of the photographing image. Further, a relative speed derivation unit 20b derives a relative speed of another vehicle running behind the own vehicle with respect to the own vehicle, and a guide line setting unit 20c determines a specified distance on the basis of the relative speed. An information superimposition unit 23 superimposes a varying guide line indicating a position of the specified distance backward from the own vehicle 9 on the surrounding image. And, an image input unit 24 outputs the surrounding image on which the varying guide line is superimposed to a display device 3 to be displayed. Thus, a driver of the own vehicle can grasp a safe positional relation between the own vehicle and another vehicle in accordance with the relative speed of another vehicle on the basis of the displayed surrounding image, and thereby the driver thereof can make an appropriate decision to change the lane.

Description

  The present invention relates to a technique for processing an image of a camera mounted on a vehicle.

  When changing a lane, a driver who drives a vehicle such as an automobile generally uses a side mirror to grasp the position of another vehicle in an adjacent lane and determines whether to change the lane. However, since it is difficult for drivers who are unfamiliar with driving to grasp the position of another vehicle based on the image shown on the side mirror, there are many drivers who are not good at judging such a lane change.

  For this reason, an image display system that generates a peripheral image showing a region reflected in a side mirror using a captured image obtained by a camera and displays a peripheral image on which a guide line as an index is superimposed on a display device in a vehicle interior is proposed. (For example, refer to Patent Document 1). In this image display system, a guide line indicating a position at a predetermined distance behind the host vehicle is superimposed on the peripheral image. By referring to such a surrounding image, the driver can relatively easily grasp the position of the other vehicle based on the guide line included in the surrounding image and the image of the other vehicle.

JP 2010-39953 A

  By the way, it is necessary for the driver to determine whether to change the lane by comprehensively considering not only the position of the other vehicle in the changed lane but also the traveling speed of the own vehicle and the relative speed of the other vehicle with respect to the own vehicle. .

  For example, when the host vehicle is traveling at a relatively high speed, a larger distance is required as the inter-vehicle distance between the host vehicle and the other vehicle than when the host vehicle is traveling at a relatively low speed. For this reason, the driver needs to determine the lane change in consideration of the traveling speed of the host vehicle.

  In addition, when another vehicle traveling in the rear is approaching the host vehicle, even if the distance between the host vehicle and the other vehicle is a necessary distance before the lane change, After the change, the distance between the vehicles will be very small. For this reason, the driver needs to determine the lane change in consideration of the relative speed of the other vehicle with respect to the own vehicle.

  However, in the conventional image display system as described above, the traveling speed, the relative speed, and the like are not taken into consideration, and the driver can only grasp the position of the other vehicle based on the guide line of the surrounding image. For this reason, it has been difficult for the driver to appropriately determine the lane change.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an image processing apparatus that allows a driver to appropriately determine lane change.

  In order to solve the above-mentioned problem, the invention of claim 1 is an image processing device for processing an image, based on image acquisition means for acquiring a captured image of a camera mounted on the own vehicle, and the captured image, Generating means for generating a peripheral image indicating a peripheral area of the host vehicle including an area reflected in a side mirror of the host vehicle, and deriving means for deriving a relative speed of the other vehicle traveling behind the host vehicle with respect to the host vehicle. Determining means for determining a specified distance based on the relative speed, superimposing means for superimposing a guide index indicating the position of the specified distance behind the host vehicle on the peripheral image, and the guide index superimposed Output means for outputting the peripheral image to a display device and displaying the peripheral image on the display device.

  The invention of claim 2 is the image processing apparatus according to claim 1, further comprising speed acquisition means for acquiring a travel speed of the host vehicle, wherein the determination means includes the travel speed and the relative speed. The designated distance is determined based on

  According to a third aspect of the present invention, in the image processing apparatus according to the first or second aspect, the determining unit increases the specified distance as the relative speed increases.

  According to a fourth aspect of the present invention, in the image processing apparatus according to any one of the first to third aspects, the image processing apparatus further includes a changing unit that changes a mode of the guide index according to the relative speed.

  According to a fifth aspect of the present invention, in the image processing apparatus according to any one of the first to fourth aspects, the determining unit determines a plurality of the designated distances based on the relative speed, and the superimposing unit includes: A plurality of the guide indices indicating the positions of the plurality of designated distances behind the host vehicle are superimposed on the peripheral image.

  The invention according to claim 6 is the image processing apparatus according to any one of claims 1 to 5, further comprising direction acquisition means for acquiring a direction indicated by the direction indicator of the host vehicle, wherein the output means is When the direction indicator indicates a direction, the peripheral image indicating the area reflected on the side mirror in the direction indicated by the direction indicator is output to the display device.

  The invention according to claim 7 is the image processing apparatus according to any one of claims 1 to 5, wherein the output means is configured such that when the other vehicle approaches the host vehicle, the other vehicle The peripheral image indicating the area reflected on the side mirror in the direction in which the image exists is output to the display device.

  The invention according to claim 8 is an image processing apparatus for processing an image, wherein an image acquisition means for acquiring a captured image of a camera mounted on the own vehicle, and a side of the own vehicle based on the captured image. A generating unit configured to generate a peripheral image indicating a peripheral region of the host vehicle including a region reflected in a mirror; a speed acquiring unit configured to acquire a traveling speed of the host vehicle; and a determining unit configured to determine a specified distance based on the traveling speed. Superimposing means for superimposing a guide index indicating the position of the specified distance behind the host vehicle on the peripheral image, and outputting the peripheral image on which the guide index is superimposed to a display device for display on the display device Output means.

  The invention of claim 9 is an image display system, wherein the image processing device according to any one of claims 1 to 8, a display device for displaying the peripheral image output from the image processing device, It has.

  The invention of claim 10 is an image processing method for processing an image, wherein (a) a step of acquiring a photographed image of a camera mounted on the host vehicle, and (b) based on the photographed image, A step of generating a peripheral image showing a peripheral region of the host vehicle including a region reflected in a side mirror of the host vehicle, and (c) a step of deriving a relative speed of the other vehicle traveling behind the host vehicle with respect to the host vehicle. (D) determining a specified distance based on the relative speed; (e) superimposing a guide index indicating the position of the specified distance behind the host vehicle on the surrounding image; and (f) Displaying the peripheral image on which the guide index is superimposed.

  The invention of claim 11 is an image processing method for processing an image, wherein (a) obtaining a photographed image of a camera mounted on the host vehicle, and (b) based on the photographed image, A step of generating a peripheral image showing a peripheral region of the host vehicle including a region reflected in a side mirror of the host vehicle, (c) acquiring a travel speed of the host vehicle of the host vehicle, and (d) the travel Determining a designated distance based on speed; (e) superimposing a guide index indicating a position of the designated distance behind the host vehicle on the peripheral image; and (f) superimposing the guide index. Displaying the peripheral image.

  According to the first to seventh and tenth aspects of the present invention, the guide index indicating the position of the designated distance according to the relative speed of the other vehicle with respect to the host vehicle is superimposed on the peripheral image. For this reason, since the driver can grasp the positional relationship between the safe own vehicle and the other vehicle according to the relative speed of the other vehicle, the driver can appropriately determine the lane change.

  In particular, according to the second aspect of the invention, the guide index indicating the position of the designated distance according to the traveling speed and the relative speed is superimposed on the peripheral image. For this reason, since the driver can grasp the safe positional relationship between the host vehicle and the other vehicle according to the traveling speed and the relative speed, the driver can appropriately determine the lane change.

  In particular, according to the invention of claim 3, since the specified distance is increased as the relative speed is increased, the driver can intuitively grasp the magnitude of the relative speed and can improve the safety in driving.

  In particular, according to the fourth aspect of the present invention, since the mode of the guide index is changed according to the relative speed, the driver can intuitively grasp the magnitude of the relative speed, and the driving safety can be improved.

  In particular, according to the fifth aspect of the present invention, the guide index indicating the position of each of the plurality of designated distances based on the relative speed is superimposed on the peripheral image. For this reason, since the driver can grasp the safer positional relationship between the own vehicle and the other vehicle according to the relative speed of the other vehicle, the safety in driving can be improved.

  In particular, according to the invention of claim 6, when the direction indicator indicates the direction, the peripheral region indicating the region reflected in the side mirror in the direction indicated by the direction indicator is displayed on the display device. For this reason, the driver can grasp the positional relationship between the safe host vehicle and the other vehicle when changing the course of the vehicle.

  Further, according to the invention of claim 7, when the other vehicle is approaching the host vehicle, the peripheral region indicating the region reflected on the side mirror in the direction in which the other vehicle exists is displayed on the display device. For this reason, the driver can grasp the positional relationship between the safe own vehicle and the approaching vehicle when there is another vehicle approaching the own vehicle.

  According to the eighth and eleventh aspects of the present invention, the guide index indicating the position of the specified distance according to the traveling speed of the host vehicle is superimposed on the peripheral image. For this reason, since the driver can grasp the positional relationship between the own vehicle and the other vehicle that is safe according to the traveling speed, the driver can appropriately determine the lane change.

FIG. 1 is a block diagram showing the configuration of the image display system. FIG. 2 is a diagram illustrating directions in which four cameras capture images. FIG. 3 is a diagram illustrating a state in the passenger compartment of the host vehicle. FIG. 4 is a diagram illustrating a method for generating a composite image. FIG. 5 is a diagram illustrating a virtual viewpoint for generating a peripheral image. FIG. 6 is a diagram illustrating an example of a peripheral image. FIG. 7 is a diagram illustrating an example of a peripheral image. FIG. 8 is a diagram illustrating an example of a peripheral image on which guide lines are superimposed. FIG. 9 is a diagram illustrating changes in the designated distance. FIG. 10 is a diagram illustrating an example of a peripheral image on which guide lines are superimposed. FIG. 11 is a diagram illustrating an example of a peripheral image on which guide lines are superimposed. FIG. 12 is a diagram illustrating an example of a peripheral image on which guide lines are superimposed. FIG. 13 is a diagram illustrating a processing flow of the image processing apparatus. FIG. 14 is a diagram illustrating an example of a peripheral image on which guide lines are superimposed. FIG. 15 is a diagram illustrating an example of a peripheral image on which guide lines are superimposed. FIG. 16 is a diagram illustrating a state in which two peripheral images are displayed on one screen.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<1. First Embodiment>
<1-1. Configuration>
FIG. 1 is a block diagram illustrating a configuration of an image display system 10 according to the first embodiment. This image display system 10 is mounted on a vehicle (in this embodiment, an automobile), and has a function of generating an image showing an area shown in a side mirror and displaying the image in a vehicle interior. A driver who is a user of the image display system 10 can use this image display system 10 to check other vehicles traveling behind the vehicle and determine whether or not to change lanes. . The image display system 10 also has a navigation function for guiding a route to the destination. Hereinafter, a vehicle on which the image display system 10 is mounted is referred to as “own vehicle”.

  As shown in the figure, the image display system 10 mainly includes a plurality of cameras 5, an image processing device 2, and a plurality of display devices 3. The plurality of cameras 5 captures the periphery of the host vehicle, acquires captured images indicating the periphery of the host vehicle, and inputs the acquired captured images to the image processing device 2. The image processing device 2 executes various image processing using a captured image or the like, and generates images to be displayed on the plurality of display devices 3. The plurality of display devices 3 display images output from the image processing device 2.

  Each of the plurality of cameras 5 includes a lens and an image sensor, and electronically obtains a photographed image showing the periphery of the host vehicle. The multiple cameras 5 include a front camera 5F, a rear camera 5B, a left side camera 5L, and a right side camera 5R. These four cameras 5F, 5B, 5L, and 5R are arranged at different positions in the own vehicle 9 and photograph different directions around the own vehicle 9.

  FIG. 2 is a diagram illustrating directions in which the four cameras 5F, 5B, 5L, and 5R are respectively photographed. The front camera 5F is provided at the front end of the host vehicle 9, and the optical axis 5Fa is directed in the straight traveling direction of the host vehicle 9. The rear camera 5 </ b> B is provided at the rear end of the host vehicle 9, and the optical axis 5 </ b> Ba is directed in the direction opposite to the straight traveling direction of the host vehicle 9. The left side camera 5L is provided on the left side mirror 93L on the left side, and its optical axis 5La is directed to the left side of the host vehicle 9 (a direction orthogonal to the straight traveling direction). Further, the right side camera 5R is provided on the right side mirror 93R on the right side, and its optical axis 5Ra is directed to the right side of the host vehicle 9 (a direction orthogonal to the straight traveling direction).

  A wide-angle lens such as a fisheye lens is adopted as the lens of these cameras 5F, 5B, 5L, 5R, and each camera 5F, 5B, 5L, 5R has an angle of view θ of 180 degrees or more. For this reason, it is possible to photograph the entire periphery of the host vehicle 9 by using the four cameras 5F, 5B, 5L, and 5R.

  Returning to FIG. 1, each of the plurality of display devices 3 includes a thin display panel such as a liquid crystal display, and displays various types of information and images. The plurality of display devices 3 include a main display 31, a left sub display 32, and a right sub display 33. These three display devices 3 are arranged in the passenger compartment so that the driver can visually recognize the screen while sitting in the driver's seat of the host vehicle 9.

  FIG. 3 is a view showing a state of the interior of the own vehicle 9. The main display 31 is provided on the center console 96 at the center of the left and right sides of the vehicle interior. The left sub-display 32 and the right sub-display 33 are provided on the left side and the right side of the meter panel 94 of the host vehicle 9, respectively. The screen sizes of the two sub-displays 32 and 33 are smaller than the main display 31.

  Further, as shown in the figure, the operation buttons 4 included in the image display system 10 are provided on the left side and the right side of the steering wheel 95 of the host vehicle 9, respectively. These left and right operation buttons 4 are operation members that receive the operation of the driver. When any one of the operation buttons 4 is operated by the driver, a signal indicating the operation content is input to the image processing apparatus 2 (see FIG. 1).

  Returning to FIG. 1, the image processing apparatus 2 is an electronic apparatus that can perform various types of image processing, and includes an image acquisition unit 21, an image generation unit 22, an information superimposition unit 23, and an image output unit 24. .

  The image acquisition unit 21 acquires captured images respectively obtained by the four cameras 5F, 5B, 5L, and 5R. The image acquisition unit 21 has an image processing function such as a function of converting an analog captured image into a digital captured image. The image acquisition unit 21 performs predetermined image processing on the acquired captured image and inputs the processed captured image to the image generation unit 22.

  The image generation unit 22 is a hardware circuit that performs image processing for generating a composite image. The image generation unit 22 has a function of combining a plurality of captured images acquired by the plurality of cameras 5 to generate a combined image that shows the surroundings of the host vehicle 9 viewed from a virtual viewpoint. The image generation unit 22 generates a peripheral image indicating a region reflected on the side mirrors 93L and 93R by the function of generating the composite image. A method by which the image generation unit 22 generates a peripheral image will be described later.

  The information superimposing unit 23 superimposes various information necessary for the driver on the peripheral image generated by the image generating unit 22. For example, the information superimposing unit 23 superimposes a guide line or the like serving as a guide for the distance from the rear end of the host vehicle 9 on the peripheral image.

  The image output unit 24 selectively outputs an image to be displayed such as a peripheral image to one of the three display devices 3. Thus, the image is displayed on the display device 3 from which the image has been output.

  The image processing apparatus 2 further includes a control unit 20, a storage unit 25, a signal reception unit 26, and a navigation unit 27. The control unit 20 is, for example, a microcomputer, and comprehensively controls the entire image processing apparatus 2.

  The storage unit 25 is a non-volatile memory such as a flash memory, for example, and stores various types of information. The storage unit 25 stores a program as firmware and various data used for control by the control unit 20.

  The signal receiving unit 26 receives signals from other devices provided in the host vehicle 9. The signal receiving unit 26 inputs the received signal to the control unit 20. The signal receiving unit 26 receives signals from the vehicle speed sensor 91 and the direction indicator 92. The signal receiving unit 26 receives a signal indicating a traveling speed (km / h) that is an absolute speed at which the host vehicle 9 travels from the vehicle speed sensor 91. Further, the signal receiving unit 26 receives from the direction indicator 92 a signal indicating the direction indicated by the direction indicator 92, which is the direction in which the driver indicates the intention to change the course. That is, the signal receiving unit 26 acquires the traveling speed of the host vehicle 9 and the direction indicated by the direction indicator 92.

  The navigation unit 27 is an electronic component that realizes a navigation function for guiding a route to a destination. The navigation unit 27 displays a map image indicating a route to the destination on the main display 31 via the image output unit 24. Thereby, a map image for navigation is usually displayed on the main display 31.

  The control unit 20 includes a CPU, a RAM, a ROM, and the like. Various functions of the control unit 20 are realized by the CPU performing arithmetic processing according to a program stored in the storage unit 25. A vehicle detection unit 20a, a relative speed deriving unit 20b, a guide line setting unit 20c, and a display control unit 20d shown in the drawing are a part of functional units realized by the CPU performing arithmetic processing according to a program.

  The vehicle detection unit 20 a detects another vehicle that travels behind the host vehicle 9 based on the captured image acquired by the image acquisition unit 21. In the present embodiment, the rear side of the host vehicle 9 may be a region behind the rear end of the host vehicle 9, and not only the same lane as the lane in which the host vehicle 9 travels but also the host vehicle 9. This is a region including other lanes such as adjacent lanes adjacent to the lane where the vehicle travels.

  The relative speed deriving unit 20 b derives the relative speed of the other vehicle traveling behind the host vehicle 9 with respect to the host vehicle 9. The guide line setting unit 20c sets the position and mode of the guide line to be superimposed on the peripheral image. In addition, the display control unit 20d selects a peripheral image to be displayed, and selects the display device 3 to display the peripheral image. Then, the display control unit 20d controls the image output unit 24 to output the selected peripheral image to the selected display device 3.

  Details of the processing of the functional units 20a to 20d realized by the control unit 20 will be described later.

<1-2. Generation of peripheral images>
Next, a method in which the image generation unit 22 generates a peripheral image indicating an area reflected on the side mirrors 93L and 93R will be described. First, a method for generating a composite image showing the surroundings of the host vehicle 9 viewed from a virtual viewpoint will be described. FIG. 4 is a diagram illustrating a method in which the image generation unit 22 generates a composite image.

  When shooting is performed with each of the front camera 5F, the rear camera 5B, the left side camera 5L, and the right side camera 5R, four images PF and PB showing the front, rear, left side, and right side of the host vehicle 9, respectively. , PL, PR are acquired. These four images PF, PB, PL, and PR include data around the entire vehicle 9.

  First, the image generation unit 22 projects data (values of each pixel) included in these four images PF, PB, PL, and PR onto a projection surface TS that is a three-dimensional curved surface in a virtual three-dimensional space. The projection surface TS has, for example, a substantially hemispherical shape (a bowl shape). The center part (bottom part of the bowl) of the projection surface TS is determined as the position of the host vehicle 9. Further, the portion other than the center of the projection surface TS is associated with any one of the images PF, PB, PL, and PR.

  The image generation unit 22 projects the data included in the images PF, PB, PL, PR on a portion other than the center of the projection surface TS. The image generation unit 22 projects the data of the image PF of the front camera 5F onto an area corresponding to the front of the host vehicle 9 on the projection surface TS. Further, the image generation unit 22 projects the data of the image PB of the rear camera 5B on an area corresponding to the rear of the host vehicle 9 on the projection surface TS. Furthermore, the image generation unit 22 projects the data of the image PL of the left side camera 5L on the projection surface TS in the region corresponding to the left side of the host vehicle 9, and the region corresponding to the right side of the host vehicle 9 in the projection surface TS. The data of the image PR of the right side camera 5R is projected onto.

  When data is thus projected onto each part of the projection surface TS, the image generation unit 22 then virtually constructs a polygon model indicating the three-dimensional shape of the host vehicle 9. The model of the host vehicle 9 is arranged at the center of the projection plane TS that is determined as the position of the host vehicle 9 in the three-dimensional space where the projection plane TS is set.

  Next, the image generation unit 22 sets a virtual viewpoint VP for the three-dimensional space. The image generation unit 22 can set the virtual viewpoint VP at an arbitrary viewpoint position in the three-dimensional space in an arbitrary visual field direction. Then, the image generation unit 22 cuts out, as an image, an area included in the predetermined viewing angle from the set virtual viewpoint VP in the projection surface TS. Further, the image generation unit 22 performs rendering on the polygon model according to the set virtual viewpoint VP, and superimposes the two-dimensional vehicle image 90 as a result on the cut-out image. Thereby, the image generation part 22 produces | generates the synthetic | combination image CP which shows the area | region around the own vehicle 9 and the own vehicle 9 seen from the virtual viewpoint VP.

  For example, as shown in the figure, when a virtual viewpoint VPa is set with the viewpoint position directly above the host vehicle 9 and the view direction directly below, a composite image CPa overlooking the host vehicle 9 and the area around the host vehicle 9 is obtained. Generated. When the virtual viewpoint VPb is set with the viewpoint position at the left rear of the host vehicle 9 and the visual field direction at the front of the host vehicle 9, the host vehicle 9 can be seen from the left rear of the host vehicle 9. And the synthetic | combination image CPb which shows the area | region of the periphery of the own vehicle 9 is produced | generated.

  The image generation unit 22 uses the function of generating such a composite image to generate a peripheral image that indicates an area shown on the side mirrors 93L and 93R. The image generation unit 22 adjusts the viewpoint position and visual field direction of the virtual viewpoint VP in order to generate this peripheral image. FIG. 5 is a diagram illustrating a virtual viewpoint set for generating a peripheral image.

  As illustrated in FIG. 5, the image generation unit 22 sets a virtual viewpoint VPR with the viewpoint position as the position of the right side mirror 93R and the visual field direction as the center of the region reflected in the right side mirror 93R. By setting this virtual viewpoint VPR, the image generation unit 22 can generate a peripheral image indicating a peripheral region of the host vehicle 9 including a region reflected on the right side mirror 93R when viewed from the driver. The image included in this peripheral image is reversed left and right and has the same orientation as the image reflected on the right side mirror 93R.

  FIG. 6 is a diagram illustrating an example of the peripheral image SP corresponding to the right side mirror 93R. As shown in FIG. 6, this peripheral image SP shows a peripheral region of the host vehicle 9 including a region Ma reflected on the right side mirror 93R. In the peripheral image SP, a portion corresponding to the region Ma reflected on the right side mirror 93R is surrounded by a frame Mf having the same shape as that of the right side mirror 93R.

  Further, the peripheral image SP includes an image of the other vehicle 8 that travels behind the host vehicle 9 and a vehicle image 90 that shows a part of the vehicle body of the host vehicle 9. Therefore, the user can confirm the peripheral image SP with the same feeling as that of the right side mirror 93R.

  Further, as illustrated in FIG. 5, the image generation unit 22 also sets a virtual viewpoint VPL in which the viewpoint position is the position of the left side mirror 93L and the visual field direction is the center of the region reflected in the left side mirror 93L. By setting this virtual viewpoint VPL, the image generation unit 22 can generate a peripheral image indicating the peripheral region of the host vehicle 9 including the region reflected on the left side mirror 93L when viewed from the driver. The image included in the peripheral image is reversed left and right and has the same orientation as the image reflected on the left side mirror 93L.

  FIG. 7 is a diagram illustrating an example of the peripheral image SP corresponding to the left side mirror 93L. As shown in FIG. 7, the peripheral image SP shows a peripheral region of the host vehicle 9 including a region Ma reflected on the left side mirror 93L. In the peripheral image SP, a portion corresponding to the region Ma reflected on the left side mirror 93L is surrounded by a frame Mf having the same shape as the left side mirror 93L. The user can confirm the peripheral image SP with the same feeling as that of the left side mirror 93L.

<1-3. Guide line>
The information superimposing unit 23 superimposes a guide line on the peripheral image generated in this way. In addition, the guide line setting unit 20c determines the position and mode of the guide line to be superimposed on the peripheral image. Hereinafter, this guide line will be described. FIG. 8 shows an example of the peripheral image SP on which guide lines are superimposed. As shown in FIG. 8, two guide lines L0 and L1 are superimposed on the peripheral image SP.

  One guide line L0 indicates the position of the rear end of the host vehicle 9 in the peripheral image SP (that is, the position that is 0 m backward from the rear end). The position of the guide line L0 is fixed in the peripheral image SP. Hereinafter, the guide line L0 is referred to as a “reference guide line”.

  The other guide line L1 indicates a position that is a specified distance backward from the rear end of the host vehicle 9 in the peripheral image SP. In the example of FIG. 8, the guide line L <b> 1 indicates a position 20 m away from the rear end of the host vehicle 9. The guide line setting part 20c can change the designated distance (distance from the rear end to the rear of the host vehicle 9) indicated by the guide line L1. Accordingly, the position of the guide line L1 in the peripheral image SP varies according to the specified distance. Hereinafter, the guide line L1 is referred to as a “variable guide line”.

  The fluctuation guide line L1 is a measure of the positional relationship between the safe host vehicle 9 and the other vehicle 8 when changing the lane. That is, the driver can use the fluctuation guide line L1 when determining whether or not to change the lane. Specifically, the driver changes the lane relatively safely when the image of the other vehicle 8 traveling in the adjacent lane behind the host vehicle 9 is behind the fluctuation guide line L1 in the surrounding image SP. Judge that it can be done. In other words, the specified distance indicated by the guide line L1 corresponds to the inter-vehicle distance between the host vehicle 9 and the other vehicle 8 (hereinafter referred to as “safe inter-vehicle distance”) that can change the lane relatively safely.

  The safe inter-vehicle distance varies according to the traveling speed of the host vehicle 9 and the relative speed of the other vehicle 8 with respect to the host vehicle 9. For example, when the host vehicle 9 is traveling at a relatively high speed, a larger distance is required as the safe inter-vehicle distance than when the host vehicle 9 is traveling at a relatively low speed. In addition, when the lane change is performed when the other vehicle 8 is approaching the own vehicle 9, the inter-vehicle distance between the own vehicle 9 and the other vehicle 8 may become very small after the lane change. For this reason, when the other vehicle 8 approaches, the safe inter-vehicle distance needs to be increased as the absolute value of the relative speed of the other vehicle 8 with respect to the own vehicle 9 is increased.

  For this reason, the guide line setting unit 20 c determines the designated distance based on the traveling speed of the host vehicle 9 and the relative speed of the other vehicle 8 with respect to the host vehicle 9. When the designated distance is D (m), the traveling speed of the own vehicle 9 is V1 (km / h), and the relative speed of the other vehicle 8 with respect to the own vehicle 9 is V2 (km / h), the designated distance D is, for example, Determined in (1).

D = V1 / 2 + V2 × 0.75 (1)
In the present embodiment, the relative speed V2 is a positive (+) value when the other vehicle 8 approaches the own vehicle 9 (when the other vehicle 8 is earlier than the own vehicle 9). When the vehicle is separated (when the other vehicle 8 is slower than the host vehicle 9), the value is negative (−).

  FIG. 9 is a diagram illustrating a change in the designated distance D based on Expression (1). The vertical axis in the figure indicates the designated distance D, and the horizontal axis in the figure indicates the relative speed V2. The graph line FL1 indicates the specified distance D when the traveling speed V1 is 40 (km / h), and the graph line FL2 indicates the specified distance D when the traveling speed V1 is 60 (km / h).

  As shown in the figure, the designated distance D changes according to the traveling speed V1 and the relative speed V2. As indicated by the graph lines FL1, L2, when the traveling speed V1 is constant, the specified distance D increases as the relative speed V2 increases. Assuming that the relative speed V2 is constant, the designated distance D increases as the traveling speed V1 increases. When the relative speed V2 is negative (−) (when the other vehicle 8 is separated) or when the other vehicle 8 cannot be detected, the relative speed V2 is set to 0 and the specified distance D is determined.

  The guide line setting unit 20c thus determines the designated distance D based on the traveling speed V1 and the relative speed V2. Then, the guide line setting unit 20c controls the information superimposing unit 23 to superimpose the variation guide line L1 on the coordinate position in the peripheral image SP corresponding to the specified distance. The correspondence between the designated distance D and the coordinate position in the peripheral image SP is determined by a table. A table indicating this correspondence relationship is stored in advance in the storage unit 25 or the like.

  FIG. 8 described above shows the peripheral image SP when the traveling speed V1 is 40 (km / h) and the relative speed V2 is 0 (km / h). In this case, the designated distance D is 20 (m). For this reason, the surrounding image SP includes a fluctuation guide line L1 indicating a position of 20 (m) rearward from the rear end of the host vehicle 9.

  FIG. 10 is a diagram showing the peripheral image SP when the traveling speed V1 is 40 (km / h) and the relative speed V2 is 20 (km / h). In this case, the designated distance D is 35 (m). For this reason, the surrounding image SP includes a fluctuation guide line L1 indicating a position of 35 (m) behind the rear end of the host vehicle 9. In the case of FIG. 8 and FIG. 10, the traveling speed V1 is the same, but the relative speed V2 is larger in the case of FIG. For this reason, the designated distance D is larger in the case of FIG.

  FIG. 11 is a diagram illustrating the peripheral image SP when the traveling speed V1 is 60 (km / h) and the relative speed V2 is 20 (km / h). In this case, the designated distance D is 45 (m). For this reason, the surrounding image SP includes a fluctuation guide line L1 indicating a position of 45 (m) behind the rear end of the host vehicle 9. In the case of FIG. 10 and FIG. 11, the relative speed V2 is the same, but the traveling speed V1 is larger in the case of FIG. For this reason, the designated distance D is larger in the case of FIG.

  Thus, the fluctuation guide line L1 indicating the position of the designated distance D corresponding to the traveling speed V1 and the relative speed V2 is superimposed on the peripheral image SP. For this reason, the driver can grasp the positional relationship between the own vehicle 9 and the other vehicle 8 safely according to the traveling speed V1 and the relative speed V2 by visually recognizing the surrounding image SP. Can be done.

  Further, as shown in FIGS. 8, 10 and 11, the peripheral image SP is superimposed with character information of distances indicated by the two guide lines L0 and L1 together with the two guide lines L0 and L1. Character information “0 m” is superimposed in the vicinity of the end of the fixed guide line L0. In addition, the character information of the designated distance D indicated by the variation guide line L1 is superimposed in the vicinity of the end portion of the variation guide line L1. For example, in the case of FIG. 10, since the designated distance D is 35 (m), the character information “35 m” is superimposed, and in the case of FIG. 11, the designated distance D is 45 (m), so that the character information “45 m”. Are superimposed. The guide line setting unit 20c controls the information superimposing unit 23 to superimpose such character information on the peripheral image SP. The driver of the host vehicle 9 can clearly grasp the distances indicated by the guide lines L0 and L1 by visually recognizing the character information.

  Further, as can be seen by comparing FIG. 8, FIG. 10, and FIG. 11, the horizontal length of the fluctuation guide line L1 in the peripheral image SP is changed according to the designated distance D indicated by the fluctuation guide line L1. . Specifically, the length of the variation guide line L1 increases as the designated distance D indicated by the variation guide line L1 decreases. In addition, the length of the fixed guide line L0 indicating the rear end of the host vehicle 9 is larger than the fluctuation guide line L1. As described above, the guide line setting unit 20c sets the lengths of the guide lines L1 and L0 to be larger as the distance indicated by the guide lines L1 and L0 is smaller. By adjusting the lengths of the guide lines L1 and L0 in this way, the guide lines L1 and L0 are represented in the same manner as the perspective method in the peripheral image SP. Thereby, it is possible to give the driver who visually recognizes the peripheral image SP a perspective similar to the image of the subject with respect to the guide lines L1 and L0. As a result, the driver can intuitively grasp the designated distance D indicated by the variation guide line L1.

  Further, the guide line setting unit 20c changes the mode of the fluctuation guide line L1 according to the relative speed V2. The guide line setting unit 20c determines the risk level when the lane is changed based on the relative speed V2, and changes the mode of the variable guide line L1 so as to increase the alerting effect as the risk level increases.

  Specifically, the guide line setting unit 20c sets the color of the variation guide line L1 to “yellow” and the relative speed V2 when the relative speed V2 is equal to or lower than a predetermined threshold (for example, 20 km / h in the present embodiment). When the value exceeds the threshold, the color of the variation guide line L1 is set to “red”. If the relative speed V2 is 0 or less (when the other vehicle 8 is separated or the other vehicle 8 travels at the same speed as the host vehicle 9) or when the other vehicle 8 cannot be detected, the lane is changed. However, the risk of contact with the other vehicle 8 is low. Therefore, in this case, the guide line setting unit 20c sets the color of the variable guide line L1 to “blue” indicating safety. In addition, when the relative speed V2 exceeds the threshold, the guide line setting unit 20c increases the thickness of the variable guide line L1 as compared with the case where the relative speed V2 is equal to or less than the threshold.

  FIG. 12 is a diagram illustrating the peripheral image SP when the traveling speed V1 is 40 (km / h) and the relative speed V2 is 40 (km / h). In this case, the designated distance D is 50 (m). For this reason, the surrounding image SP includes a fluctuation guide line L1 indicating a position of 50 (m) behind the rear end of the host vehicle 9. In the case of FIG. 12, the relative speed V2 exceeds the threshold value of 20 (km / h). For this reason, the color of the variation guide line L1 is “yellow” in the case of FIGS. 8, 10, and 11, whereas it is “red” in the case of FIG. In the case of FIG. 12, the thickness of the variation guide line L1 is thicker than that of the cases of FIGS.

  As described above, the guide line setting unit 20c determines the degree of danger when the lane is changed according to the relative speed V2, and changes the mode of the variable guide line L1 so as to enhance the alerting effect according to the degree of danger. To do. Thereby, the driver can intuitively grasp that the relative speed V2 is relatively large and the degree of danger when the lane is changed is high. As a result, driving safety can be improved.

<1-4. Processing of Image Processing Device>
Next, a processing flow of the image processing apparatus 2 that generates such a peripheral image will be described. . FIG. 13 is a diagram illustrating a flow of processing of the image processing apparatus 2. The processing shown in FIG. 13 is repeated at a predetermined cycle (for example, 1/30 second cycle).

  First, each of the four cameras 5 captures images, and the image acquisition unit 21 acquires four captured images from these four cameras 5. The image acquisition unit 21 inputs the acquired four captured images to the image generation unit 22 and the control unit 20 (step S11).

  Next, the image generation unit 22 uses the four captured images to perform a peripheral image (hereinafter referred to as “right peripheral image”) SP indicating a region reflected on the right side mirror 93R and a left side mirror by the above-described method. Peripheral images (hereinafter, referred to as “left peripheral images”) SP indicating the area shown in 93L are respectively generated (step S12).

  Next, the signal receiving unit 26 receives a signal from the vehicle speed sensor 91 and acquires the traveling speed V1 of the host vehicle 9. The signal receiving unit 26 inputs the acquired traveling speed V1 to the control unit 20 (step S13).

  Next, the vehicle detection unit 20a detects the other vehicle 8 traveling behind the host vehicle 9 based on the captured image of the rear camera 5B among the captured images acquired by the image acquisition unit 21 (step S14). The vehicle detection unit 20a may detect the other vehicle 8 based on the captured images of the side cameras 5L and 5R. However, since the rear camera 5B has less distortion of the image of the other vehicle 8 and the size of the image becomes larger, it is desirable to use the captured image of the rear camera 5B in terms of detection accuracy.

  The vehicle detection unit 20a can detect the other vehicle 8 by using a known method such as an optical flow method, for example. In the optical flow method, a feature point is extracted from each of a plurality of time-sequential captured images (frames), and an object is detected based on an optical flow indicating the movement of the feature points between the plurality of captured images. It is. In the case of the present embodiment, the optical flow of the background image extends with a certain length in the direction of the vanishing point. Therefore, an optical flow other than such an optical flow is determined as the optical flow of the image of the other vehicle 8. be able to.

  Further, the vehicle detection unit 20a detects that the detected other vehicle 8 is located on the right rear side, the left rear side, and the same lane of the own vehicle 9 from the horizontal coordinate position in the captured image of the detected image of the other vehicle 8. Determine where it is behind.

  Next, the relative speed deriving unit 20b derives the detected relative speed V2 of the other vehicle 8 with respect to the host vehicle 9 (step S15). First, the relative speed deriving unit 20b derives the relative distance of the other vehicle 8 with respect to the host vehicle 9 from the vertical coordinate position in the captured image of the image of the other vehicle 8. The correspondence between the coordinate position in the captured image and the relative distance is determined by a table. A table indicating this correspondence relationship is stored in advance in the storage unit 25 or the like.

  Then, the relative speed deriving unit 20b determines the own speed of the other vehicle 8 based on the relative distance of the other vehicle 8 derived in the past process, the relative distance of the other vehicle 8 derived in the current process, and the processing cycle. A relative speed V2 with respect to the vehicle 9 is derived. As described above, the relative speed deriving unit 20b derives a positive (+) relative speed V2 when the other vehicle 8 is approaching the host vehicle 9, and the other vehicle 8 is compared with the host vehicle 9. When 8 is separated, a relative speed V2 having a negative (−) value is derived.

  Next, the guide line setting unit 20c determines the designated distance D based on the traveling speed V1 of the host vehicle 9 and the relative speed V2 of the other vehicle 8 with respect to the host vehicle 9 using the above-described equation (1). (Step S16). Furthermore, the guide line setting unit 20c determines the position of the variation guide line L1 based on the determined designated distance D, and sets the mode (color, thickness, etc.) of the variation guide line L1 based on the relative speed V2. (Step S17).

  When there are other vehicles 8 on the right rear side and the left rear side of the host vehicle 9, the guide line setting unit 20c determines the designated distance D for each of the right other vehicle 8 and the left other vehicle 8. . And the guide line setting part 20c sets the position and aspect of the fluctuation | variation guide line L1 regarding each of the right side and the left side of the own vehicle 9. FIG.

  Next, the information superimposing unit 23 superimposes information such as the two guide lines L0 and L1 and the distance character information on the peripheral image SP (step S18). The information superimposing unit 23 superimposes the variation guide line L1 related to the right side of the host vehicle 9 on the right peripheral image SP, and superimposes the variation guide line L1 related to the left side of the host vehicle 9 to the left peripheral image SP.

  Next, the display control unit 20d determines whether any of the three display conditions for displaying the peripheral image SP generated as described above is satisfied (steps S19, S20, and S21). If none of the display conditions is satisfied (No in all of Steps S19, S20, and S21), the process ends as it is.

  The display control unit 20d first determines whether or not the display condition that the direction indicator 92 is ON (the driver indicates the intention to change the course) is satisfied (step S19). The display control unit 20d determines this display condition based on the signal from the direction indicator 92 acquired by the signal receiving unit 26.

  When the direction indicator 92 is on (Yes in step S19), the display control unit 20d indicates an area reflected on the side mirror in the direction indicated by the direction indicator 92, of the two generated left and right peripheral images SP. A peripheral image SP is selected (step S22). Further, the display control unit 20d selects a sub-display in the direction indicated by the direction indicator 92 from the two left and right sub-displays 32 and 33. Then, the display control unit 20d controls the image output unit 24 to output the selected peripheral image SP to the selected sub display (step S23). As a result, the peripheral image SP in the direction indicated by the direction indicator 92 is displayed on the sub-display in the direction indicated by the direction indicator 92.

  For example, when the direction indicated by the direction indicator 92 is “left”, the left peripheral image SP is displayed on the left sub-display 32. Further, when the direction indicated by the direction indicator 92 is “right”, the right peripheral image SP is displayed on the right sub-display 33.

  In this way, when the direction indicator 92 is on, the peripheral image SP indicating the area reflected on the side mirror in the direction indicated by the direction indicator 92 is displayed. Therefore, the driver can grasp the safe positional relationship between the host vehicle 9 and the other vehicle 8 when changing the lane of the host vehicle 9. As a result, the driver can appropriately determine whether or not to change the lane.

  The display control unit 20d determines whether or not the display condition that the other vehicle 8 is approaching the host vehicle 9 is satisfied (step S20). The display control unit 20d determines this display condition based on the sign of the relative speed V2 of the other vehicle 8 with respect to the host vehicle 9.

  When the other vehicle 8 is approaching the host vehicle 9 (Yes in step S20), the display control unit 20d includes the approaching other vehicle 8 among the generated two left and right peripheral images SP. A peripheral image SP indicating a region reflected in the direction side mirror is selected (step S22). Furthermore, the display control unit 20d selects a sub-display in the direction in which the approaching other vehicle 8 exists, from the left and right sub-displays 32 and 33. Then, the display control unit 20d controls the image output unit 24 to output the selected peripheral image SP to the selected sub display (step S23). As a result, the peripheral image SP in the direction in which the approaching other vehicle 8 exists is displayed on the sub-display in the direction in which the approaching other vehicle 8 exists.

  For example, when the direction in which the approaching other vehicle 8 exists is “left side”, the left peripheral image SP is displayed on the left sub-display 32. When the direction in which the approaching other vehicle 8 exists is “right side”, the right peripheral image SP is displayed on the right sub-display 33.

  As described above, when the other vehicle 8 is approaching the host vehicle 9, the peripheral image SP indicating the region shown in the side mirror in the direction in which the other vehicle 8 exists is displayed. For this reason, the driver can grasp the existence of the approaching other vehicle 8 and the safe positional relationship between the own vehicle 9 and the other vehicle 8 when the other vehicle 8 approaching the own vehicle 9 exists. Can do.

  The display control unit 20d determines whether or not the display condition that the operation button 4 is operated by the driver is satisfied (step S21). The display control unit 20d determines this display condition based on the signal from the operation button 4.

  When the operation button 4 is operated by the driver (Yes in Step S21), the display control unit 20d displays the side in the direction in which the operated operation button 4 is arranged among the two generated left and right peripheral images SP. A peripheral image SP indicating a region reflected in the mirror is selected (step S22). Furthermore, the display control unit 20d selects a sub-display in the direction in which the operated operation button 4 is arranged, from the left and right sub-displays 32 and 33. Then, the display control unit 20d controls the image output unit 24 to output the selected peripheral image SP to the selected sub display (step S23). As a result, the peripheral image SP in the direction in which the operated operation button 4 is arranged is displayed on the sub-display in the direction in which the operated operation button 4 is arranged.

  For example, when the “left” operation button 4 is operated, the left peripheral image SP is displayed on the left sub-display 32. Further, when the “right” operation button 4 is operated, the right peripheral image SP is displayed on the right sub-display 33.

  In this way, when the operation button 4 is operated by the driver, the peripheral image SP indicating the area reflected on the side mirror in the direction in which the other vehicle 8 exists is displayed. For this reason, the driver can grasp the positional relationship between the safe host vehicle 9 and the other vehicle 8 at a desired timing.

  Note that the display conditions in steps S19, S20, and S21 do not necessarily need to be valid, and the user may arbitrarily select which display condition is valid. For example, when the user feels that it is troublesome to display the surrounding image SP each time the other vehicle 8 approaches, the display condition of step S20 is invalidated and only the display condition of step S19 and step S21 is valid. be able to.

  As described above, in the image processing apparatus 2, the image acquisition unit 21 acquires a captured image of the camera 5 mounted on the host vehicle 9, and the image generation unit 22 uses the captured image as a side mirror of the host vehicle 9. A peripheral image SP indicating a peripheral region of the host vehicle 9 including the region to be reflected is generated. Further, the relative speed deriving unit 20b derives the relative speed V2 of the other vehicle 8 traveling behind the own vehicle 9 with respect to the own vehicle 9, and the guide line setting unit 20c determines the designated distance D based on the relative speed V2, The information superimposing unit 23 superimposes the fluctuation guide line L1 indicating the position of the designated distance D behind the host vehicle 9 on the peripheral image SP. Then, the image output unit 24 outputs the peripheral image SP on which the variation guide line L1 is superimposed to the display device 3 and causes the display device 3 to display it. For this reason, since the driver of the own vehicle 9 can grasp the safe positional relationship between the own vehicle 9 and the other vehicle 8 according to the relative speed V2 of the other vehicle 8 based on the displayed peripheral image SP, the lane change is performed. Can be made appropriately.

  In the image processing device 2, the signal receiving unit 26 acquires the traveling speed V1 of the host vehicle 9, and the guide line setting unit 20c determines the designated distance D based on the traveling speed V1 and the relative speed V2. Therefore, the fluctuation guide line L1 indicating the position of the designated distance D according to the traveling speed V1 and the relative speed V2 is superimposed on the peripheral image SP. For this reason, the driver can grasp the safe positional relationship between the host vehicle and the other vehicle according to the traveling speed V1 and the relative speed V2, and therefore can appropriately determine the lane change.

  In addition, when the other vehicle 8 approaches, the guide line setting unit 20c increases the specified distance D as the relative speed V2 of the other vehicle 8 with respect to the host vehicle 9 increases. For this reason, the driver can intuitively grasp the magnitude of the relative speed V2, and can improve the safety in driving.

  Further, the guide line setting unit 20c changes the aspect of the fluctuation guide line L1 according to the relative speed V2. For this reason, the driver can intuitively grasp the magnitude of the relative speed V2, that is, the degree of danger when the lane is changed, and can improve the safety in driving.

<2. Second Embodiment>
Next, a second embodiment will be described. Since the configuration and processing of the image display system 10 of the second embodiment are substantially the same as those of the first embodiment, the following description will be focused on differences from the first embodiment. In the first embodiment, there is only one variation guide line whose position varies based on the traveling speed V1 and the relative speed V2, but a plurality of variation guide lines may be used. In the second embodiment, as shown in FIG. 14, two fluctuation guide lines L1, L2 are superimposed on the peripheral image SP.

  The guide line setting unit 20c of the second embodiment determines two specified distances D1 and D2 based on the traveling speed V1 and the relative speed V2. One first designated distance D1 is determined by, for example, the following equation (2) similar to equation (1) described above.

D1 = V1 / 2 + V2 × 0.75 (2)
The other second designated distance D2 is determined by the following equation (3), for example.

D2 = D1 + 10 (3)
Therefore, the second designated distance D2 is a distance with a higher degree of safety than the first designated distance D1. The guide line setting unit 20c sets the positions of the two variable guide lines L1 and L2 based on the two specified distances D1 and D2 determined as described above. Then, the information superimposing unit 23 superimposes these two variation guide lines L1 and L2 on the peripheral image SP together with the fixed guide line L0. In the surrounding image SP, the first variation guide line L1 indicates the position of the first designated distance D1 from the rear end of the host vehicle 9, and the second variation guide line L2 is second designated from the rear end of the host vehicle 9 to the rear. This indicates the position of the distance D2.

  FIG. 14 shows a peripheral image SP when the traveling speed V1 is 40 (km / h) and the relative speed V2 is 20 (km / h). In the case of FIG. 14, the first designated distance D1 is 35 (m), and the second designated distance D2 is 45 (m). For this reason, the surrounding image SP includes a first variation guide line L1 indicating the position of 35 (m) rearward from the rear end of the host vehicle 9, and a second variation guide line L2 indicating the position of 45 (m). include.

  Thus, in the second embodiment, the guide line setting unit 20c determines the two specified distances D1 and D2 based on the traveling speed V1 and the relative speed V2, and the information superimposing unit 23 sets the two specified distances D1. , D2 are respectively superimposed on the surrounding image SP. For this reason, since the driver can grasp the safer positional relationship between the host vehicle 9 and the other vehicle 8, the driving safety can be further improved. In this embodiment, two fluctuation guide lines L1 and L2 are superimposed on the peripheral image SP, but three or more fluctuation guide lines L1 and L2 may be superimposed.

<3. Modification>
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made. Below, such a modification is demonstrated. All the forms including the above-described embodiment and the form described below can be appropriately combined.

  The peripheral image SP of the above embodiment also shows the external area of the area Ma reflected on the side mirror, but as shown in FIG. 15, only the area Ma reflected on the side mirror may be shown. In this way, the image of the subject included in the peripheral image SP can be enlarged, and the peripheral image SP can be confirmed in the same sense as the side mirror.

  Further, in the above embodiment, the left peripheral image indicating the area reflected on the left side mirror 93L and the right peripheral image indicating the area reflected on the right side mirror 93R are displayed on different display devices 3, but for example, the main You may display on one display apparatuses 3, such as the display 31. FIG. FIG. 16 is a diagram illustrating a state in which both the left and right peripheral images SPL and SPR are displayed on the screen of the main display 31. In such a case, as shown in the figure, it is desirable to display the left peripheral image SPL on the left side of the screen and the right peripheral image SPR on the right side of the screen.

  Moreover, in the said embodiment, although the color and thickness were changed as the aspect of the fluctuation | variation guide line changed based on relative speed V2, you may make it change another aspect. For example, the type of the variation guide line (a solid line, a broken line, a one-dot chain line, or the like) may be changed. Further, when the relative speed V2 is relatively large, the fluctuation guide line may be blinked.

  In the above-described embodiment, the mode of the fluctuation guide line is changed according to the relationship between the relative speed V2 and the threshold value. However, even if the mode of the fluctuation guide line is changed according to the magnitude of the relative speed V2. Good. For example, the thickness of the variation guide line may be increased as the relative speed V2 is increased.

  In the above embodiment, when the other vehicle 8 is approaching the host vehicle 9, the positive (+) relative speed V <b> 2 is derived, but conversely, the other vehicle 8 approaches. In this case, a negative (−) relative speed V2 may be derived. In this case, the description regarding “the magnitude of the relative speed V2” may be read as “the magnitude of the absolute value of the relative speed V2”.

  In the above embodiment, the character information of the designated distance D indicated by the fluctuation guide line L1 is shown near the end of the fluctuation guide line L1, but may be shown outside the frame Mf. By doing in this way, it can prevent that character information overlaps with the image of the subject existing in the area reflected on the side mirror.

  Further, in the above embodiment, the peripheral image indicating the region shown in the side mirror is generated by the function of generating the composite image. On the other hand, the peripheral image may be generated based only on the captured image obtained by the side cameras 5L and 5R. In this case, for example, a peripheral image can be generated by cutting out a region behind the host vehicle 9 in the captured image and correcting the distortion of the subject image. Alternatively, a peripheral image may be generated by cutting out a central region of a captured image of a side camera installed with the optical axis directed toward the rear of the host vehicle 9.

  Moreover, in the said embodiment, although the relative speed V2 with respect to the own vehicle 9 of the other vehicle 8 was derived | led-out based on the picked-up image, you may derive | lead-out by another method. For example, the radar which detects the other vehicle 8 is installed in the rear end of the own vehicle 9, the relative distance of the other vehicle 8 is calculated | required based on the signal which a radar detects, and relative speed V2 is derived | led-out based on this relative distance. Also good. Alternatively, the rear camera 5B and one of the side cameras 5L and 5R may be used as a stereo camera to determine the relative distance of the other vehicle 8, and the relative speed V2 may be derived based on this relative distance.

  Moreover, in the said embodiment, although the guide parameter | index which shows the position of designation | designated distance back from the own vehicle 9 was a guide line, other indicators, such as the symbol continuously arranged in the horizontal direction, may be sufficient.

  Moreover, the specific numerical values of the formulas (1) to (3) in the above embodiment are merely examples, and other numerical values may be used according to the performance of the host vehicle 9, the skill of the driver, and the like.

  In the above embodiment, when the traveling speed V1 is constant, the designated distance D changes linearly with respect to the relative speed V2, but may change nonlinearly.

  Moreover, although the said embodiment demonstrated that the other vehicle 8 was detected using an optical flow system, you may detect the other vehicle 8 using other methods, such as a frame difference method and a template matching.

  Further, in the above-described embodiment, it has been described that various functions are realized in software by the arithmetic processing of the CPU according to the program. However, some of these functions are realized by an electrical hardware circuit. Also good. Conversely, some of the functions realized by the hardware circuit may be realized by software.

DESCRIPTION OF SYMBOLS 10 Image display system 2 Image processing apparatus 3 Display apparatus 4 Operation button 5 Camera 8 Other vehicle 9 Own vehicle 20b Relative speed deriving part 20c Guide line setting part 23 Information superimposition part

Claims (11)

An image processing apparatus for processing an image,
Image acquisition means for acquiring a captured image of a camera mounted on the host vehicle;
Generating means for generating a peripheral image indicating a peripheral region of the host vehicle including a region reflected in a side mirror of the host vehicle based on the captured image;
Derivation means for deriving a relative speed of the other vehicle traveling behind the host vehicle with respect to the host vehicle;
Determining means for determining a specified distance based on the relative speed;
Superimposing means for superimposing a guide index indicating the position of the specified distance behind the host vehicle on the peripheral image;
Output means for outputting the peripheral image on which the guide index is superimposed to a display device to display on the display device;
An image processing apparatus comprising: The image processing apparatus according to claim 1.
Speed acquisition means for acquiring the traveling speed of the host vehicle;
Further comprising
The image processing apparatus according to claim 1, wherein the determining unit determines the designated distance based on the traveling speed and the relative speed. The image processing apparatus according to claim 1 or 2,
The determination means increases the specified distance as the relative speed increases. The image processing apparatus according to any one of claims 1 to 3,
Changing means for changing the mode of the guide index according to the relative speed,
An image processing apparatus further comprising: The image processing apparatus according to any one of claims 1 to 4,
The determining means determines a plurality of the designated distances based on the relative speed,
The image processing apparatus, wherein the superimposing unit superimposes a plurality of the guide indexes indicating positions of the plurality of designated distances behind the host vehicle on the peripheral image. The image processing apparatus according to any one of claims 1 to 5,
Direction acquisition means for acquiring the direction indicated by the direction indicator of the host vehicle;
Further comprising
The output means outputs, when the direction indicator indicates a direction, the peripheral image indicating an area reflected on the side mirror in the direction indicated by the direction indicator to the display device. apparatus. The image processing apparatus according to any one of claims 1 to 5,
The output means outputs, when the other vehicle is approaching the host vehicle, the peripheral image showing an area reflected on the side mirror in a direction in which the other vehicle exists, to the display device. An image processing apparatus. An image processing apparatus for processing an image,
Image acquisition means for acquiring a captured image of a camera mounted on the host vehicle;
Generating means for generating a peripheral image indicating a peripheral region of the host vehicle including a region reflected in a side mirror of the host vehicle based on the captured image;
Speed acquisition means for acquiring the traveling speed of the host vehicle;
Determining means for determining a specified distance based on the traveling speed;
Superimposing means for superimposing a guide index indicating the position of the specified distance behind the host vehicle on the peripheral image;
Output means for outputting the peripheral image on which the guide index is superimposed to a display device to display on the display device;
An image processing apparatus comprising: An image display system,
An image processing apparatus according to any one of claims 1 to 8,
A display device for displaying the peripheral image output from the image processing device;
An image display system comprising: An image processing method for processing an image,
(A) acquiring a photographed image of a camera mounted on the host vehicle;
(B) generating a peripheral image indicating a peripheral region of the host vehicle including a region reflected in a side mirror of the host vehicle based on the captured image;
(C) deriving a relative speed of another vehicle traveling behind the host vehicle with respect to the host vehicle;
(D) determining a designated distance based on the relative speed;
(E) superimposing a guide index indicating the position of the specified distance behind the host vehicle on the peripheral image;
(F) displaying the peripheral image on which the guide index is superimposed;
An image processing method comprising: An image processing method for processing an image,
(A) acquiring a photographed image of a camera mounted on the host vehicle;
(B) generating a peripheral image indicating a peripheral region of the host vehicle including a region reflected in a side mirror of the host vehicle based on the captured image;
(C) obtaining a travel speed of the host vehicle of the host vehicle;
(D) determining a designated distance based on the travel speed;
(E) superimposing a guide index indicating the position of the specified distance behind the host vehicle on the peripheral image;
(F) displaying the peripheral image on which the guide index is superimposed;
An image processing method comprising:

Images