JP2003267171A - Device for monitoring rear part of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To display the images of a rear part of a vehicle to be easily seen by a driver and to properly make the images correspond to actual states. <P>SOLUTION: At a stage when a self vehicle starts reverse traveling, actual images on the rear part of the self vehicle imaged by a CCD 4 are displayed on a display 2. The images displayed on the display 2 are successively switched from the actual images to converted images and from converted images of low viewpoints to converted images of high viewpoints as a distance from the present position of the self vehicle to a target position becomes shorter. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle rear monitoring device for displaying an image of the rear of a vehicle on a display means when the vehicle is traveling backward and urging the vehicle to travel backward appropriately.

[0002]

2. Description of the Related Art Conventionally, when a vehicle travels backward, an image of the rear of the vehicle is displayed on a display installed in the vehicle interior, and the driver is made aware of the state behind the vehicle, so that the vehicle can be appropriately driven backward. A rear monitoring device has been proposed and put into practical use.

In this type of vehicle rear monitoring device, it is an important issue to display on the display an image that is easy for the driver to see in order to allow the driver to accurately recognize the state behind the vehicle. From the viewpoint, various technical improvements have been attempted.

Specifically, for example, Japanese Patent Laid-Open No. 2001-163
In Japanese Patent Laid-Open No. 132, a camera for picking up an image of the rear of the vehicle is installed at a low position of the vehicle body, and an image of the rear of the vehicle is picked up from such a low position as a viewpoint, so that the image is displayed on the display. In order to solve the problem that the image is difficult to see, the image of the rear of the vehicle captured by the camera is converted into a virtual image when it is captured from a viewpoint higher than the actual camera viewpoint using the conversion table, A technique for displaying this converted image on a display has been proposed.

As in this example, as an image behind the vehicle,
By displaying an image from a viewpoint higher than the actual camera viewpoint on the display, an image that is easier to see than the actual image will be displayed on the display, and the driver can refer to this image. It becomes easier to recognize the situation behind the vehicle. In particular, a camera that captures an image of the rear of the vehicle is often installed at an extremely low position in the vicinity of the license plate from the viewpoints of body layout restrictions and aesthetics. Since it is very difficult to see in the visual sense, it is extremely useful to convert an image from such a low viewpoint into an image from a high viewpoint and display it on a display.

[0006]

By the way, in the case of converting an actual image (actual image) behind the vehicle, which is taken by a camera installed at a low position of the vehicle body, into an image from a high viewpoint, Japanese Patent Application Laid-Open No. 2001-163132. As disclosed in the publication, it is assumed that all images of objects appearing on the real image are on the road surface. Then, the image of the object is converted based on the position coordinates on the road surface. Therefore, non-three-dimensional objects such as white lines and characters drawn on the road surface are converted appropriately, but objects with height such as buildings and other vehicles are converted into a greatly distorted state. Will end up.

For this reason, when the driver visually recognizes the situation behind the vehicle to some extent and then starts the backward movement of the vehicle, the converted image (converted image) is immediately displayed on the display. In some cases, it may be difficult to associate the object appearing on the image with the object visually recognized by the driver, which causes a problem that the vehicle may be prevented from traveling in an appropriate backward direction.

The present invention was devised in view of the above-mentioned conventional circumstances, so that the image of the rear of the vehicle can be easily seen by the driver and can be appropriately associated with the actual situation. It is an object of the present invention to provide a vehicle rear monitoring device which is adapted to display.

[0009]

According to a first aspect of the present invention, there is provided a vehicle rear monitoring device, which is installed at a rear portion of a vehicle and which captures an image of the rear of the vehicle, and a real image of the rear of the vehicle captured by the camera. Coordinate conversion is performed to generate a converted image that is virtually imaged by taking a position higher than the actual viewpoint of the camera as a viewpoint, a real image behind the vehicle, and the converted image are selective. Display means, display control means for selecting an image to be displayed on the display means, target position setting means for setting a target position to be a target when the vehicle travels backward, and current position of the vehicle. Distance calculation means for calculating the distance from the position to the target position set by the target position setting means. Then, in the vehicle rear monitoring device, the display control unit displays the image displayed on the display unit when the distance to the target position calculated by the distance calculation unit is less than a predetermined distance. From the converted image to the converted image.

According to a second aspect of the present invention, there is provided the rear vehicle monitoring device according to the first aspect, wherein the converted image generating means generates a plurality of converted images having different viewpoint heights. The display control means sequentially switches the conversion image displayed on the display means from a conversion image with a low viewpoint to a conversion image with a high viewpoint as the distance to the target position calculated by the distance calculation means becomes shorter. It is characterized by that.

According to a third aspect of the present invention, there is provided the rear vehicle monitoring device according to the second aspect, wherein the converted image generating means sets the rear image of the vehicle as the converted image having the highest viewpoint height. It is characterized in that it generates a plane-converted image that is virtually imaged in the direction perpendicular to the road surface.

Further, a vehicle rear monitoring apparatus according to a fourth aspect is the vehicle rear monitoring apparatus according to any one of the first to third aspects, wherein the target position setting means sets the target in accordance with a user's operation input. It is characterized by setting the position.

According to a fifth aspect of the present invention, there is provided a rear vehicle monitoring system according to the fourth aspect, wherein the display control means sets the target position by the target position setting means. The plane-converted image is displayed on the display means.

The vehicle rear monitoring apparatus according to a sixth aspect of the present invention is the vehicle rear monitoring apparatus according to any one of the first to third aspects, wherein the target position setting means sets the actual image or the converted image. An edge detection process is performed, and the target position is set based on the process result.

A vehicle rear monitoring device according to a seventh aspect is the vehicle rear monitoring device according to any one of the first to sixth aspects, wherein the target position setting means sets the parking position of the vehicle to the target position. It is characterized by setting as.

Further, the vehicle rear monitoring apparatus according to claim 8 is the vehicle rear monitoring apparatus according to claim 7, wherein the target position setting means is one of the parking positions which is a stop position of the vehicle rear end portion. It is characterized in that the vicinity of the line on the back side is set as the target position.

A vehicle rear monitoring device according to a ninth aspect is the vehicle rear monitoring device according to the seventh aspect, wherein the target position setting means is in front of the parking position, which is the stop position of the front end of the vehicle. It is characterized in that the vicinity of the line on the side is set as the target position.

A vehicle rear monitoring device according to a tenth aspect of the present invention is the vehicle rear monitoring device according to the seventh aspect, wherein the target position setting means is a quadrangle of the parking position which is a space where the entire vehicle stops. A shape region is set as the target position.

The vehicle rear monitoring apparatus according to claim 11 is the vehicle rear monitoring apparatus according to any one of claims 1 to 10, wherein the display control means sets the target set by the target position setting means. It is characterized in that the position is displayed on the display means so as to be superimposed on the actual image or the converted image.

[0020]

According to the vehicle rear monitoring device of the present invention, when the distance from the current position of the vehicle to the target position is less than the predetermined distance, the image of the rear of the vehicle displayed on the display means is displayed at the rear of the vehicle. Since the actual image of the vehicle is switched to the converted image, the actual image of the rear of the vehicle captured by the camera will be displayed on the display means at the stage of starting the backward traveling of the vehicle. When starting the backward movement of the vehicle, it is possible to appropriately recognize other high-level objects such as other vehicles and buildings located behind the vehicle in the image displayed on the display means. And then
When the vehicle moves backward and approaches the target position, the image displayed on the display means can be switched to the converted image that is virtually taken from a higher viewpoint than the actual image.
The driver can more appropriately recognize the state behind the vehicle by referring to the converted image displayed on the display means. For example, when the vehicle is parked, the vehicle position is immediately before the end of parking. It becomes possible to extremely appropriately perform a driving operation such as adjusting in accordance with the white line of.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

The vehicle rear monitoring device of the present invention is applied to the vehicle system 1 as a device for realizing a function of displaying an image of the rear of the vehicle in the vehicle-mounted system 1 as shown in FIG. 1, for example.

The in-vehicle system 1 is mounted in a vehicle to present various information to an occupant of this vehicle (hereinafter referred to as the own vehicle), and is installed in the vehicle compartment to display various images. A display 2 as a display means is provided, and an image display on the display 2 is an audio / visual control device 3 as a display control means.
Is controlled by.

Further, the in-vehicle system 1 is installed at a position where the rear end of the own vehicle has a relatively low ground height, specifically, for example, near the license plate of the own vehicle, and captures an image behind the own vehicle. A CCD (Charge Coupled Device) camera 4 and a viewpoint conversion controller 5 as a conversion image generation unit that generates a conversion image by performing coordinate conversion on an image (actual image) behind the vehicle captured by the CCD camera 4 are provided. The viewpoint conversion controller 5 is connected to the audio / visual control device 3.

In addition to the viewpoint conversion controller 5, the audio / visual control device 3 includes a navigation device 6 for guiding the route of the vehicle, and various devices such as a television tuner, an audio device, and an air conditioner control device (not shown). It is connected. Then, the audio / visual control device 3 displays an image of the rear of the own vehicle from the viewpoint conversion controller 5 according to the operation input by the occupant of the own vehicle, the situation of the own vehicle determined based on the outputs from various sensors, and the like. Navigation images from the navigation device 6, TV images from the TV tuner,
An operation display screen or the like from the audio device or the air conditioner control device is selectively displayed on the display 2.

In the vehicle-mounted system 1 to which the present invention is applied, the audio / visual control device 3 is also provided.
A reverse switch 7 that is turned on when the gear of the host vehicle is shifted to the reverse position is connected to. Then, based on the reverse on signal from the reverse switch 7, the audio / visual control device 3 determines that the host vehicle starts traveling backward.

In the in-vehicle system 1, the audio / visual control device 3 is provided with a vehicle speed sensor 8 for generating a pulse signal proportional to the traveling distance of the vehicle.
Are connected. Then, based on the pulse signal from the vehicle speed sensor 8, the distance that the vehicle has traveled backward is calculated by the audio / visual control device 3.

Further, in the in-vehicle system 1, the audio / visual control device 3 is provided with a target position setting switch 9 for setting a target position which should be a target when the vehicle is traveling backward. Then, when the image behind the host vehicle is displayed on the display 2, the driver operates the target position setting switch 9 to move the marker superimposed on the image behind the host vehicle to a desired position. Thus, the driver can specify a desired target position, and based on the switch signal from the target position setting switch 9, the target position at the time of traveling the own vehicle backward is determined by the audio / visual control device 3 Is set by.

As shown in FIG. 2, the audio / visual control device 3 includes a digital I / O unit 11, a control unit 12, a communication unit 13, and a superimposed display image generation unit 14.
And an image switching unit 15 and an image synthesizing unit 16.

The digital I / O unit 11 controls input / output of various digital signals to / from the audio / visual control device 3. Various digital signals such as a reverse ON signal from the reverse switch 7, a pulse signal from the vehicle speed sensor 8 and a switch signal from the target position setting switch 9 are sent to the audio / visual control device 3 via the digital I / O unit 11. It is input and supplied to the control unit 12.

The control section 12 controls the operation of the audio / visual control apparatus 3 as a whole.
It is configured by a PU (Central Processing Unit) and the like.
In particular, the control unit 12 sets a target position when the host vehicle travels backward, a function that calculates a distance from the current position of the host vehicle to the target position, and the viewpoint conversion controller 5 according to the calculated distance. It has a function of generating a control signal Sc for controlling the coordinate conversion processing in.

That is, when the switch signal is supplied from the target position setting switch 9, the control unit 12 sets a predetermined position behind the host vehicle designated by the user as the target position in accordance with the switch signal. To do.

The control unit 12 also includes a reverse switch 7
When the reverse-on signal from the vehicle is supplied, it is determined that the host vehicle has started the backward travel, and the backward travel distance of the vehicle is calculated based on the pulse signal from the vehicle speed sensor 8. Then, the current position of the own vehicle is determined using these information and the image behind the own vehicle displayed on the display 2, and the distance from the current position of the own vehicle to the target position is calculated. Note that this distance is geometrically calculated based on the position of the marker (set target position) superimposed on the image behind the vehicle and the viewpoint and angle of view of the CCD camera or a virtual camera described later. can do.

The control unit 12 also generates a control signal Sc for controlling the coordinate conversion processing in the viewpoint conversion controller 5 according to the calculated distance from the current position of the vehicle to the target position. That is, the control signal Sc generated by the control unit 12 causes the viewpoint position of the converted image output from the viewpoint conversion controller 5 to gradually increase as the distance from the current position of the vehicle to the target position decreases. As described above, switching of coordinate conversion in the viewpoint conversion controller 5 is controlled.

The communication section 13 outputs the control signal Sc generated by the control section 12 to the viewpoint conversion controller 5.

The superimposed display image generating section 14 is a marker image indicating the target position set by the control section 12, that is,
An image of a marker to be superimposed and displayed on an image behind the host vehicle is generated.

The image switching section 15 selects an image to be displayed on the display 2. That is, the image switching unit 15 includes a display image signal S1 output from the viewpoint conversion controller 5, an image signal of a navigation image from the navigation device 6, an image signal of a television image from a television tuner, an audio device and an air conditioner control device. The image signal of the operation display screen from is selectively switched.

The image synthesizing unit 16 causes the image switching unit 15 to display the display image signal S1 from the viewpoint conversion controller 5.
When is selected, the image signal of the marker image generated by the superimposed display image data generation unit 14 is combined with this display image signal S1 to form one frame image, and the signal of this combined frame image is selected. The image signal S2 is output.

As shown in FIG. 3, the viewpoint conversion controller 5 for converting the coordinates of the actual image behind the host vehicle to generate the converted image includes the input frame buffer 21 and the coordinate conversion processing unit 2.
2, and a plurality of conversion tables 23a, 23b, 23c,
The output frame buffer 24 and the viewpoint conversion control unit 25 are provided.

The input frame buffer 21 temporarily stores the image data showing the actual image behind the vehicle captured by the CCD camera 4 in units of frames constituting one screen. That is, the image signal S0 of the real image behind the vehicle output from the CCD camera 4 in real time is converted into digital image data by an A / D converter (not shown), and then the input frame buffer 21
It is designed to be input to. Then, the image data indicating the actual image behind the host vehicle input to the input frame buffer 21 is developed and stored for each frame in the input frame buffer 21.

The coordinate conversion processing unit 22 includes the viewpoint conversion control unit 2
Under the control of 5, the image data of the actual image behind the vehicle stored in the input frame buffer 21 on a frame-by-frame basis is subjected to coordinate conversion processing. For example, DSP (Digi
tal Signal Processor). The coordinate conversion processing by the coordinate conversion processing unit 22 is performed by the viewpoint conversion control unit 25 from among the plurality of conversion tables 23a, 23b, and 23c.
Is performed based on a predetermined rule described in the conversion table selected by.

A plurality of conversion tables 23a, 23b, 23
In c, the rules for coordinate conversion of the image data of the actual image behind the vehicle input to the input frame buffer 21 are recorded. Specifically, each of these conversion tables 23a, 23b, 23c is equivalent to the input frame buffer 21.
The input frame buffer 21 has a structure in which the input frame buffer 21 has a one-to-one correspondence with the same coordinates on the conversion tables 23a, 23b, and 23c corresponding to the coordinates of each pixel of the image data stored in the input frame buffer 21. Information (address of output pixel) indicating which coordinate is to be replaced by each pixel of the stored image data by conversion is recorded.

In the following description, FIG. 4 (a)
4 (a) to 4 (a), it is premised that an image behind the host vehicle that is virtually imaged from each viewpoint (camera position) shown in FIG. 4 (c) is selectively displayed on the display 2. ), A first conversion table 23a for generating an image from the viewpoint, and a second conversion table 2 for generating an image from the viewpoint shown in FIG. 4B.
3b and a third conversion table 23c for generating the image from the viewpoint shown in FIG. 4C are provided. Here, it is assumed that the camera parameters are set such that the images from the respective viewpoints shown in FIGS. 4A to 4C have the same visual field range.

More specifically, in the first conversion table 23a, as shown in FIG. 4A, the ground height h1 and the depression angle of the camera optical axis (the downward angle of the camera optical axis with respect to a plane parallel to the road surface). ) A rule is recorded in which the image data showing the actual image behind the host vehicle, which is captured by the CCD camera 4 installed at θ1 and stored in the input frame buffer 21, is output as it is.

In the second conversion table 23b, the image data showing the actual image behind the own vehicle stored in the input frame buffer 21 is subjected to coordinate conversion, and as shown in FIG. H2 (h2> h1), depression angle θ2 (θ2
The rule for outputting as image data of the converted image viewed from the viewpoint of the virtual camera A that is virtually installed at> θ1) is recorded.

In the third conversion table 23c, the image data showing the actual image behind the own vehicle stored in the input frame buffer 21 is subjected to coordinate conversion, and as shown in FIG. H3 (h3> h2), depression angle θ3 (θ3
≅90 degrees>θ2> θ1) The converted image viewed from the viewpoint of the virtual camera B, that is, the planar converted image that is assumed to be an image behind the vehicle in the direction perpendicular to the road surface. The rule for outputting as image data is recorded.

Here, in order to simplify the configuration, C
Even when the image data showing the actual image behind the vehicle captured by the CD camera 4 is output as it is, the formal coordinate conversion is performed using the first conversion table 23a. When the image data showing the actual image of the rear of the vehicle captured by is output as it is, the circuit configuration may be used in which the conversion table is not used and the output is through.

The image data showing the actual image behind the vehicle taken by the CCD camera 4 is coordinate-converted into the image data of the image viewed from the viewpoint of the virtual camera A and the image data of the image viewed from the viewpoint of the virtual camera B. Algorithm is CC
It is geometrically uniquely determined from the camera parameters of the D camera 4 and the virtual camera A and the virtual camera B.

That is, first, the ground coordinate system obtained from the camera parameters of the virtual cameras A and B,
Virtual CCD in these virtual cameras A and B
The correspondence with the surface coordinate system is obtained, and which coordinate on the ground coordinate system each pixel of the virtual CCD surface coordinate system in the virtual camera A or virtual camera B corresponds to is calculated. next,
Correspondence between the ground coordinate system obtained from the camera parameters of the virtual cameras A and B and the ground coordinate system obtained from the actual camera parameters of the CCD camera 4 is obtained, and the camera parameters of the virtual cameras A and B are obtained. Each coordinate of the ground coordinate system obtained from the actual CCD
Which coordinate on the ground coordinate system obtained from the camera parameter of the camera 4 is calculated. Next, the correspondence relationship between the ground coordinate system obtained from the camera parameters of the actual CCD camera 4 and the CCD plane coordinate system of the CCD camera 4 is obtained, and the ground coordinate system obtained from the camera parameters of the actual CCD camera 4 is obtained. Each coordinate is CCD
Which pixel in the CCD plane coordinate system in the camera 4 corresponds is calculated. With the above procedure, the actual CCD
The CCD plane coordinate system of the camera 4 and the virtual CCD plane coordinate system of the virtual camera A or the virtual camera B are associated with each other, and the corresponding relations are recorded in the second conversion table 23b and the third conversion table 23c, respectively. It will be. The details of the coordinate conversion algorithm as described above are disclosed in Japanese Patent Laid-Open No. 2001-163132.

The output frame buffer 24 temporarily stores the image data subjected to the coordinate conversion processing by the coordinate conversion processing section 22 and outputs the stored image data as output image data in units of frames at a predetermined timing. It is a thing. The output image data output from the output frame buffer 24 is converted into an analog display image signal S1 by a D / A converter (not shown) and then supplied to the audio / visual control device 3.

The viewpoint conversion control section 25 controls the coordinate conversion processing in the coordinate conversion processing section 22 based on the control signal Sc from the audio / visual control device 3, and is composed of a CPU and the like. For example, the audio / visual control device 3 determines that the host vehicle starts to travel backward, and the control signal Sc including a signal to that effect is sent from the audio / visual control device 3 to the viewpoint conversion control unit of the viewpoint conversion controller 5. When supplied to 25, the viewpoint conversion control unit 25 controls the start of the coordinate conversion processing in the coordinate conversion processing unit 22.

After the host vehicle starts traveling backward, the audio / visual control device 3 calculates the distance from the current position of the vehicle to the target position for traveling backward, and outputs a signal indicating the distance to the target position. When the containing control signal Sc is supplied from the audio / visual control device 3 to the viewpoint conversion control unit 25 of the viewpoint conversion controller 5, the viewpoint conversion control unit 25 causes the distance from the current position of the own vehicle to the target position for backward traveling. Accordingly, the process of selecting the conversion table to be used for the coordinate conversion process in the coordinate conversion processing unit 22 from the plurality of conversion tables 23a, 23b, 23c is performed.

Regarding this conversion table selection processing, when the driving operation of moving the own vehicle backward and parking in the parking space is performed, the target position of the backward running is set to the parking space which is the stop position of the rear end of the own vehicle. A case in which the host vehicle is set near the line on the back side and the vehicle travels backward toward the target position will be specifically described as an example.

At the time when the host vehicle starts traveling backward toward the target position, the distance D from the present position P1 of the host vehicle to the target position P2 is usually a long distance as shown in FIG. 5 (a). Has become. Here, the current position P1 of the host vehicle indicates the position of the rear end of the host vehicle in which the CCD camera 4 is installed, for example. The current position P1 of the own vehicle traveling backward after the own vehicle starts traveling backward
The distance D from the target position P2 to the preset first
The viewpoint conversion control unit 25 selects the first conversion table 23a as the conversion table used for the coordinate conversion processing in the coordinate conversion processing unit 22 while the viewpoint conversion distance D1 is greater than or equal to D1 (for example, 7 m). As described above, the first conversion table 23a is for displaying the actual image behind the host vehicle as it is, which is captured by the CCD camera 4 installed in the host vehicle at the installation position shown in FIG. 4A. It is a conversion table. As a result, the audio / visual control device 3 is supplied with the display image signal S1 indicating the actual image behind the vehicle. Then, as the selected image signal S2 supplied to the display 2 by the audio / visual control device 3, the display image signal S1 showing the actual image behind the host vehicle is selected, and the marker image showing the target position is displayed on the display image signal S1. By superimposing and outputting the result, the display 2 is displayed, for example, as shown in FIG.
An actual image (image captured by the CCD camera 4) behind the host vehicle as shown in (a) is displayed.

The own vehicle travels backward and approaches the parking space. As shown in FIG. 5B, the distance D from the present position P1 of the own vehicle to the target position P2 is the first viewpoint conversion distance D1.
When reaching (for example, 7 m), the viewpoint conversion control unit 25 switches the conversion table used for the coordinate conversion processing in the coordinate conversion processing unit 22 from the first conversion table 23 a to the second conversion table 23 b. Then, the distance D from the current position P1 of the own vehicle traveling backwards to the target position P2 is
While the distance is less than the first viewpoint conversion distance D1 and equal to or more than the preset second viewpoint conversion distance D2 (for example, 5 m), the viewpoint conversion control unit 25 causes the coordinate conversion processing unit 2 to operate.
The second conversion table 23b is selected as the conversion table used for the coordinate conversion processing in 2. As described above, the second conversion table 23b performs coordinate conversion on the actual image behind the own vehicle captured by the CCD camera 4, and the image viewed from the viewpoint of the virtual camera A shown in FIG. 4B. It is a conversion table for generating (converted image).
As a result, the audio / visual control device 3 is supplied with the display image signal S1 indicating the converted image viewed from the viewpoint of the virtual camera A. Then, as the selected image signal S2 supplied to the display 2 by the audio / visual control device 3, the display image signal S1 showing the converted image viewed from the viewpoint of the virtual camera A is selected, and the target position is set to this display image signal S1. By superimposing and outputting the marker image shown, a converted image as shown in, for example, FIG. 6B is displayed on the display 2. In the display example shown in FIG. 6B, the area where the image is not displayed is the area outside the field of view of the CCD camera 4, and the coordinate conversion is not possible.

Further, the own vehicle travels backward and further approaches the parking space, and as shown in FIG. 5C, the distance D from the present position P1 of the own vehicle to the target position P2 is the second viewpoint conversion distance D2. When reaching (for example, 5 m), the viewpoint conversion control unit 25 switches the conversion table used for the coordinate conversion processing in the coordinate conversion processing unit 22 from the second conversion table 23 b to the third conversion table 23 c. Then, until the own vehicle traveling backward is parked in the parking space,
The viewpoint conversion control unit 25 selects the third conversion table 23c as a conversion table used for coordinate conversion in the coordinate conversion processing unit 22. This third conversion table 23c
Is a coordinate conversion of the real image behind the vehicle captured by the CCD camera 4 as described above, and is an image (planar conversion image) viewed from the viewpoint of the virtual camera B shown in FIG. 4C.
It is a conversion table for generating. As a result, the audio / visual control device 3 is supplied with the display image signal S1 indicating the plane conversion image viewed from the viewpoint of the virtual camera B. Then, as the selection image signal S2 supplied to the display 2 by the audio / visual control device 3, the display image signal S1 indicating the plane conversion image viewed from the viewpoint of the virtual camera B is selected,
By superimposing and outputting the marker image indicating the target position on the display image signal S1, the display 2 displays a plane-converted image as shown in FIG. 6C, for example. In the display example shown in FIG. 6C, the area where the image is not displayed is the area outside the visual field range of the CCD camera 4, and is the portion where the coordinate conversion cannot be performed.

The first viewpoint conversion distance D1 and the second viewpoint conversion distance D2, which serve as a reference for conversion table selection processing, are described.
Can be set arbitrarily, but considering a general driving operation when the vehicle is traveling backward and is parked in the parking space, the first viewpoint conversion distance D1 is about 7 m,
It seems appropriate to set the viewpoint conversion distance D2 of about 5 m.

Further, the ground height h1 of the CCD camera 4 installed at the rear end of the vehicle and the depression angle θ1 of the camera optical axis, the ground height h2 of the virtual camera A and the depression angle θ2 of the camera optical axis, and a virtual hypothesis. Although the ground height h3 of the camera B and the depression angle θ3 of the camera optical axis can be set arbitrarily,
It seems appropriate to set θ1 to about 45 degrees when h1 is about 1 m, θ2 to about 60 degrees when h2 is about 2 m, and θ3 to about 90 degrees when h3 is about 7 m.

When the respective parameters are set as described above, the image behind the host vehicle displayed on the display 2 is
Depending on the distance D from the current position of the host vehicle to the target position,
As shown in FIG. 7, a virtual image is obtained when a camera is used in which the height of the ground and the depression angle of the optical axis of the camera are switched stepwise.

Here, the vehicle-mounted system 1 to which the present invention is applied.
Regarding a series of processing operations in, when performing the driving operation of moving the vehicle backward and parking the vehicle in the parking space, the vicinity of the line on the back side of the parking space, which is the stop position of the rear end of the vehicle, is set as the target position. A specific description will be given with reference to the flowcharts of FIGS. 8 and 9 by taking as an example the case where the host vehicle travels backward toward the target position. In the in-vehicle system 1, as described above, the image of the rear of the vehicle from the viewpoint conversion controller 5, the navigation image from the navigation device 6, the television image from the TV tuner, the operation from the audio device or the air conditioner control device. The display screen or the like is selectively displayed on the display 2 in accordance with the situation of the host vehicle judged based on the operation input by the occupant of the host vehicle or the outputs from various sensors. It is assumed that the navigation image from the navigation device 6 is displayed on the display 2 when the host vehicle is traveling forward, and the image behind the host vehicle from the viewpoint conversion controller 5 is displayed on the display 2 when the host vehicle is traveling backward.

When the on-vehicle system 1 is powered on and started to operate, during normal forward traveling, first, in step S1-1 of FIG. 8, the audio / visual control device 3 supplies the display 2 to the display 2. The image signal from the navigation device 6 is selected as the selected image signal S2 to be selected, and the navigation image from the navigation device 6 is displayed on the display 2. The navigation image from the navigation device 6 displays the current position of the vehicle detected by the GPS or the like in a superimposed manner on the map image.

While displaying the navigation image on the display 2, whether or not a reverse on signal is supplied from the reverse switch 7, that is, whether or not the gear position of the own vehicle is shifted to the reverse, is an audio / visual control device. 3 is constantly monitored (step S1-2). Then, if it is determined that the gear position of the host vehicle is not shifted in the reverse direction, the display of the navigation image is continued.

On the other hand, if it is determined in step S1-2 that the gear position of the vehicle has been shifted to the reverse, then in step S1-3, the audio / visual control device 3 determines the state of the parking flag. It The parking flag is a flag indicating whether or not the target position for parking the own vehicle in the parking space is set.

In step S1-3, the parking flag is set to O.
If it is determined that the FF, that is, the target position has not been set, next, in step S1-4, an image (actual image) behind the host vehicle is captured by the CCD camera 4 installed behind the host vehicle, An image signal S0 showing an actual image behind the vehicle captured by the CCD camera 4 is converted into digital image data and taken into the input frame buffer 11 of the viewpoint conversion controller 5. Then, the image signal S0 indicating the actual image behind the own vehicle passes through the coordinate conversion processing unit 22 through, is temporarily stored in the output frame buffer 24, and then is supplied to the audio / visual control device 3. The selected image signal S2 is selected by the audio / visual control device 3 and supplied to the display 2. As a result, the actual image behind the host vehicle is displayed on the display 2 as an image for setting the target position.

When the image for setting the target position is displayed on the display 2, next, in step S1-5, the audio / visual control device is operated according to the designation by the driver using the target position setting switch 9. The target position setting process is performed by the control unit 12 of No. 3. Specifically, when the switch signal from the target position setting switch 9 is supplied to the audio / visual control device 3, a marker image is generated in the superimposed display image generation unit 14 according to the processing of the control unit 12, and this marker image is generated. The image is combined by the image combining unit 16 with the actual image behind the vehicle. Then, the driver sets the target position setting switch 9
Is operated to move the marker to a desired position in the image displayed on the display 2, for example, near the line on the far side of the parking space, as shown in FIG. The vicinity of the side line is set as the target position.

Next, in step S1-6, when the audio / visual control device 3 determines that the setting process of the target position is completed, step S1-
At 7, the parking flag is set.

When the parking flag is set in step S1-7 or when it is determined that the parking flag is ON in step S1-3, next, in step S1-8, the audio / visual control device 3 is operated. From the current position of the vehicle, step S1
The distance D to the target position set in -5 is calculated.
The distance D from the current position of this vehicle to the target position
Can be geometrically calculated based on the position of the marker superimposed on the image behind the vehicle, the viewpoint and the angle of view of the CCD camera 4 (or virtual camera), etc., as described above.

Next, in step S1-9, whether the calculated distance D from the current position of the vehicle to the target position is less than a preset first viewpoint conversion distance D1 (for example, 7 m). Is determined by the audio / visual control device 3. Then, when the distance D from the current position of the host vehicle to the target position is equal to or greater than the first viewpoint conversion distance D1, the control signal Sc including a signal to that effect is the viewpoint conversion control unit 15 of the viewpoint conversion controller 5.
Is supplied to.

In step S1-10, an image (actual image) behind the subject vehicle is captured by the CCD camera 4 installed behind the subject vehicle, and the actual image behind the subject vehicle is captured by the CCD camera 4. Image signal S0 shown
Is converted into digital image data and taken into the input frame buffer 21 of the viewpoint conversion controller 5.

Image data showing an actual image of the rear of the vehicle captured by the CCD camera 4 is loaded into the input frame buffer 21 of the viewpoint conversion controller 5, and the viewpoint conversion control unit 25 receives the audio / visual control device 3
When the control signal Sc from is supplied, the coordinate conversion processing unit 2
The coordinate conversion process in 2 is started. At this time, the control signal Sc from the audio / visual control device 3 recognizes that the distance D from the current position of the vehicle to the target position is equal to or greater than the first viewpoint conversion distance D1. Reference numeral 25 denotes a conversion table used for the coordinate conversion processing in the coordinate conversion processing unit 22, which is C
The first conversion table 23a for displaying the actual image of the rear of the vehicle captured by the CD camera 4 as it is is selected.

Then, in step S1-11, the coordinate conversion processing unit 22 performs a formal coordinate conversion process using the first conversion table 23a, and the image data captured in the input frame buffer 21 is converted into the own vehicle. The image data representing the rear actual image is taken into the output frame buffer 24 as it is. Then, from this output frame buffer 24, image data showing a real image behind the vehicle is output at a predetermined timing, converted into an analog display image signal S1 and supplied to the audio / visual control device 3.

When the display image signal S1 from the viewpoint conversion controller 5 is supplied to the audio / visual control device 3, the selected image signal S2 is supplied to the display 2 by the audio / visual control device 3 in step S1-12. The display image signal S1 from the viewpoint conversion controller 5 is selected, and the image of the rear of the vehicle is displayed on the display 2. At this time, the display image signal S1 from the viewpoint conversion controller 5 is CC
Since it is an image signal indicating the actual image behind the own vehicle captured by the D camera 4, the display 2 displays the actual image behind the own vehicle captured by the CCD camera 4.

While the actual image behind the vehicle is displayed on the display 2, it is constantly monitored by the audio / visual control device 3 whether or not the gear position of the vehicle is held in reverse (step S1- 1
3). Then, when it is determined that the gear position of the host vehicle is shifted from the reverse position, the process returns to step S1-1, the image signal from the navigation device 6 is selected as the selected image signal S2 to be supplied to the display 2, and the display 2 is displayed. The navigation image from the navigation device 6 is displayed again.

On the other hand, when it is determined in step S1-13 that the gear position of the host vehicle is held in reverse, the process returns to step S1-9 and the distance D from the current position of the host vehicle to the target position is set to the first position. It is again determined whether the viewpoint conversion distance D1 is less than 1. Then, until the distance D from the current position of the host vehicle to the target position becomes less than the first viewpoint conversion distance D1, the processes from step S1-9 are repeated, and the CCD camera 4 takes an image on the display 2. The actual image behind the host vehicle is continuously displayed.

In step S1-9, the distance D from the current position of the vehicle to the target position is the first viewpoint conversion distance D1.
If it is determined that the number is less than, then the step S in FIG.
In 2-1, the audio / visual control device 3 determines whether or not the distance D from the current position of the vehicle to the target position is less than a preset second viewpoint conversion distance D2 (for example, 5 m). It If the distance D from the current position of the host vehicle to the target position is less than the first viewpoint conversion distance D1 and is greater than or equal to the second viewpoint conversion distance D2, a control signal including a signal to that effect. Sc is the viewpoint conversion control unit 1 of the viewpoint conversion controller 5.
5 is supplied.

In step S2-2, the image (actual image) behind the subject vehicle is captured by the CCD camera 4 installed behind the subject vehicle, and the actual image behind the subject vehicle is captured by the CCD camera 4. The image signal S0 shown is
It is converted into digital image data and taken into the input frame buffer 21 of the viewpoint conversion controller 5.

Image data showing an actual image behind the vehicle captured by the CCD camera 4 is loaded into the input frame buffer 21 of the viewpoint conversion controller 5, and the viewpoint conversion control unit 25 receives the audio / visual control device 3
When the control signal Sc from the audio / visual control device 3 is supplied,
The distance D from the current position of the host vehicle to the target position is less than the first viewpoint conversion distance D1 and the second viewpoint conversion distance D
Since it is recognized that the number is 2 or more, the viewpoint conversion control unit 2
Reference numeral 5 is a conversion table used for the coordinate conversion processing in the coordinate conversion processing unit 22, and is a conversion of the actual image behind the vehicle captured by the CCD camera 4 as seen from the viewpoint of the virtual camera A shown in FIG. Second for coordinate conversion to image
The conversion table 23b is selected.

Then, in step S2-3, the coordinate conversion processing unit 22 performs the coordinate conversion processing using the second conversion table 23b, and the image data captured in the input frame buffer 21 is the viewpoint of the virtual camera A. The image data is converted into image data showing a converted image of the rear of the vehicle viewed from above, and is taken into the output frame buffer 24. Then, from this output frame buffer 24, the virtual camera A
The image data showing the converted image of the rear of the own vehicle viewed from the viewpoint is output at a predetermined timing, converted into an analog display image signal S1, and supplied to the audio / visual control device 3.

Then, the display image signal S1 is selected as the selection image signal S2 to be supplied to the display 2 by the audio / visual control device 3, and in step S2-4, the rear side of the vehicle viewed from the viewpoint of the virtual camera A is selected. The converted image will be displayed on the display 2.

Whether or not the gear position of the own vehicle is held in reverse while the converted image of the rear of the own vehicle viewed from the viewpoint of the virtual camera A is displayed on the display 2 is determined by the audio / visual control device 3. It is constantly monitored (step S2-5). When it is determined that the gear position of the host vehicle has been shifted from the reverse position,
Returning to step S1-1 in FIG. 8, the image signal from the navigation device 6 is selected as the selected image signal S2 to be supplied to the display 2, and the navigation image from the navigation device 6 is displayed again on the display 2.

On the other hand, if it is determined in step S2-5 that the gear position of the host vehicle is held in reverse,
Returning to step S2-1, it is determined again whether the distance D from the current position of the host vehicle to the target position is less than the second viewpoint conversion distance D2. The distance D from the current position of the host vehicle to the target position is the second viewpoint conversion distance D2.
Until the number becomes less than, the processing from step S2-1 onward is repeatedly performed, and the converted image of the rear of the vehicle viewed from the viewpoint of the virtual camera A is continuously displayed on the display 2.

In step S2-1, the distance D from the current position of the vehicle to the target position is the second viewpoint conversion distance D2.
When it is determined that the number is less than 1, the viewpoint conversion control unit 1 of the viewpoint conversion controller 5 outputs a control signal Sc including a signal to that effect.
5 is supplied.

In step S2-6, the image (actual image) behind the subject vehicle is captured by the CCD camera 4 installed behind the subject vehicle, and the actual image behind the subject vehicle is captured by the CCD camera 4. The image signal S0 shown is
It is converted into digital image data and taken into the input frame buffer 21 of the viewpoint conversion controller 5.

Image data showing an actual image of the rear of the vehicle captured by the CCD camera 4 is loaded into the input frame buffer 21 of the viewpoint conversion controller 5, and the viewpoint conversion control unit 25 receives the audio / visual control device 3
When the control signal Sc from the audio / visual control device 3 is supplied,
Since it is recognized that the distance D from the current position of the host vehicle to the target position is less than the second viewpoint conversion distance D2, the viewpoint conversion control unit 25 performs conversion used in the coordinate conversion processing in the coordinate conversion processing unit 22. As a table, CCD camera 4
The third conversion table 23c for performing the coordinate conversion of the real image rearward of the vehicle captured by is converted into a plane conversion image viewed from the viewpoint of the virtual camera B shown in FIG. 3C.

Then, in step S2-7, the coordinate conversion processing unit 22 performs coordinate conversion processing using the third conversion table 23c, and the image data taken into the input frame buffer 21 is the viewpoint of the virtual camera B. The image data is converted into image data showing a plane-converted image of the rear of the own vehicle viewed from above, and is taken into the output frame buffer 24. Then, from this output frame buffer 24, the virtual camera B
The image data showing the plane-converted image of the rear of the vehicle viewed from the viewpoint is output at a predetermined timing, converted into an analog display image signal S1, and supplied to the audio / visual control device 3.

Then, the display image signal S1 is selected as the selection image signal S2 to be supplied to the display 2 by the audio / visual control device 3, and in step S2-8, the rear side of the host vehicle seen from the viewpoint of the virtual camera B is selected. The plane conversion image will be displayed on the display 2.

While the display 2 displays the plane-converted image of the rear of the own vehicle viewed from the viewpoint of the virtual camera B, whether or not the own vehicle has reached the target position is indicated by the audio.
It is constantly judged by the visual control device 3 (step S2-9). When it is determined that the host vehicle has reached the target position, in step S2-10,
The parking flag is reset, the process returns to step S1-1 in FIG. 8, and the image signal from the navigation device 6 is selected as the selected image signal S2 supplied to the display 2,
The navigation image from the navigation device 6 is displayed again on the display 2.

If it is determined in step S2-9 that the host vehicle has not reached the target position, then in step S2-11 it is determined whether the gear position of the host vehicle is held in reverse. When it is determined by the audio / visual control device 3 that the gear position of the host vehicle is shifted from the reverse position,
Returning to step S1-1, the image signal from the navigation device 6 is selected as the selected image signal S2 to be supplied to the display 2, and the navigation image from the navigation device 6 is displayed on the display 2 again.

On the other hand, if it is determined in step S2-11 that the gear position of the host vehicle is held in reverse, the processing from step S2-6 is repeated,
The plane-converted image of the rear of the vehicle viewed from the viewpoint of the virtual camera B is continuously displayed on the display 2.

As described above, in the in-vehicle system 1 to which the present invention is applied, when the image behind the vehicle is displayed on the display 2 when the vehicle travels backward,
At the stage of starting the backward traveling of the host vehicle, the actual image behind the host vehicle captured by the CCD camera 4 is displayed on the display 2, and the distance D from the current position of the host vehicle to the target position is a predetermined distance (first When it becomes less than the viewpoint conversion distance D1 and the second viewpoint conversion distance D2), the converted image that is virtually viewed from a higher viewpoint than the viewpoint of the CCD camera 4 is displayed on the display 2. When starting the backward traveling of the own vehicle, the person appropriately selects an object with height such as another vehicle or a building existing behind the own vehicle in the actual image behind the own vehicle displayed on the display 2. In addition, when the host vehicle approaches the target position, the state behind the host vehicle can be recognized more appropriately by referring to the converted image that is easier to see than the actual image.

Further, in this in-vehicle system 1, the image behind the host vehicle displayed on the display 2 is switched step by step according to the distance D from the present position of the host vehicle to the target position, and at the start of backward traveling. When the actual image of the rear of the vehicle captured by the CCD camera 4 is displayed, the vehicle travels backward, and the distance D from the current position of the vehicle to the target position becomes less than the first viewpoint conversion distance D1, the CCD
A converted image that is virtually viewed from a viewpoint higher than the viewpoint of the camera 4 is displayed, the own vehicle further travels backward, and the distance D from the current position of the own vehicle to the target position is less than the second viewpoint conversion distance D2. Then, since a plane conversion image that is virtually viewed as seen from a higher point of view in the direction perpendicular to the road surface is displayed, switching the image behind the own vehicle displayed on the display 2 makes the driver feel uncomfortable. It can be done smoothly without giving. Especially when parking the vehicle in the parking space while traveling backwards,
A plane-converted image of the rear of the own vehicle is displayed on the display 2 just before the end of parking, so that the driver adjusts the vehicle position according to the white line of the parking section while referring to the plane-converted image. It becomes possible to perform various driving operations extremely appropriately.

Further, in this in-vehicle system 1, the image behind the host vehicle displayed on the display 2 is switched according to the distance D from the current position of the host vehicle to the target position. Even if the switching operation is performed during the operation and the distance to the target position increases again, the image of the optimum viewpoint is appropriately selected in the relationship between the current position of the vehicle and the target position. Can be displayed on the display 2.

The on-vehicle system 1 described above shows one application example of the present invention, and various technical changes can be made within the scope of realizing the features of the present invention. For example, in the in-vehicle system 1 described above, the image behind the vehicle displayed on the display 2 is a real image, a converted image that is virtually viewed from a higher viewpoint than the actual image, and a vertical image with respect to the road surface that is higher than the converted image. The plane-converted image that is virtually viewed when viewed in the direction is switched in three stages, but the image behind the vehicle displayed on the display 2 is switched in two stages: a real image and a transformed image, or a real image and a plane-transformed image. You may do it. Also in this case, similarly to the example described above, at the time of starting the backward traveling of the own vehicle, it is possible to allow the driver to properly recognize a height object such as another vehicle or a building behind the own vehicle. When the host vehicle approaches the target position, the driver can appropriately recognize the state behind the host vehicle.

Further, in the above-described in-vehicle system 1, the image of the rear of the vehicle displayed on the display 2 is switched in three steps as shown in FIG. A larger number of images may be generated so that the image of the rear of the vehicle displayed on the display 2 can be switched in multiple stages. In this case, the viewpoint conversion controller 5 is further provided with a large number of conversion tables, and the large number of conversion tables are selectively used to perform the coordinate conversion processing in the coordinate conversion processing unit 22, so that the viewpoint heights are mutually different. Different converted images will be sequentially generated. Then, as the distance from the current position of the host vehicle to the target position becomes shorter, the converted images having different viewpoint heights are displayed on the display 2 in order from the converted image having the lower viewpoint.

As described above, in the case where the converted images having different viewpoint heights are displayed on the display 2 in order from the image with the lower viewpoint, the image displayed on the display 2 behind the vehicle is further switched. It can be done smoothly.

In the above description, the case where the vehicle is parked in the parking space is set as the target position near the line on the back side of the parking space which is the stop position of the rear end of the vehicle. However, the setting of the target position when the host vehicle is parked in the parking space is not limited to the above example, and as shown in, for example, FIGS. 10A and 10B, the stop position of the front end of the host vehicle is set. The vicinity of the line on the near side of the parking space may be set as the target position. In this case, similarly to the above-mentioned example, when the rear end of the own vehicle on which the CCD camera 4 is installed is the current position of the own vehicle, the distance from the current position of the own vehicle to the target position is different from the above example. The difference will be the vertical length of the space.
Therefore, when the vicinity of the line on the front side of the parking space, which is the stop position of the front end of the host vehicle, is set as the target position, the length of the parking space in the vertical direction is taken into consideration, and the conversion table selection process reference Distance (viewpoint conversion distance D
1, D2), the same effect can be obtained by the same processing as the above-mentioned example. In particular,
For example, if the length of the parking space in the vertical direction is 5 m, the first viewpoint conversion distance D1 is set to 2 m and the second viewpoint conversion distance D2 is set to 0 m. The same effect can be obtained by the processing.

As in this example, when the target position for parking the own vehicle in the parking space is set near the line on the front side of the parking space which is the stop position of the front end of the own vehicle, As shown in 10 (b), the host vehicle is diagonally stopped with respect to the parking space at the time of starting the backward traveling for parking, and another vehicle is parked at a position adjacent to the parking space. The target position can be appropriately set even when there is such a situation. That is, FIG.
In the situation shown in (b), the CCD camera 4
Although the back side of the parking space in which the vehicle is parked cannot be confirmed from the image captured by, by setting the target position near the line on the front side of the parking space, which is the stop position of the front end of the vehicle, The above problems can be effectively avoided.

Further, the target position when the own vehicle is parked in the parking space is set as a range by directly using the rectangular frame for the entire parking space, as shown in FIGS. 11 (a) and 11 (b). You may do it. In this case,
The position used as a reference when calculating the distance from the current position of the host vehicle to the target position is any position in the rectangular area set as the target position, for example, near the line on the back side or on the front side. By determining in advance the barycentric position of the vicinity of the line or the rectangular area, it is possible to obtain the same effect by the same processing as the above-described example.

When the target position for parking the own vehicle in the parking space is set as a rectangular area as in this example, the own vehicle is set in the parking space as shown in FIG. 11 (b). Even when parking in parallel parking, it is possible to properly recognize the target parking space without confusing the target parking space with the parking space adjacent thereto. That is, when the own vehicle is parked in parallel, if the target position is set near the line on the back side or near the line on the front side of the target parking space, the target position is set near the boundary with the adjacent parking space. Therefore, it is expected that the target parking space will be misunderstood, but by setting the target position as a rectangular area, the above problems can be effectively avoided.

Further, as described above, when the target position setting process is performed, the actual image behind the host vehicle captured by the CCD camera 4 is displayed on the display 2, and the target position is set on the actual image behind the host vehicle. However, the target position is set on the plane conversion image behind the vehicle viewed from the viewpoint of the virtual camera B as shown in FIG. 12, for example. Good. In this case, after capturing an actual image of the rear of the vehicle in step S1-4 of FIG. 8 described above, the image data indicating this actual image is subjected to coordinate conversion using the third conversion table 23c of the viewpoint conversion controller 5. After that, the target position setting process may be performed by supplying the audio / visual control device 3 with the plane-converted image of the rear of the vehicle viewed from the viewpoint of the virtual camera B on the display 2.

As in this example, if the target position setting process is performed on the plane-converted image behind the host vehicle, the target position is desired while the distance from the present position of the host vehicle is properly grasped. The position can be set accurately.

Further, in the above, the audio / audio is output in response to the operation input by the driver using the target position setting switch 9.
The case where the visual control device 3 sets the target position has been described as an example. However, the viewpoint conversion controller 5 is made to have a function as a target position setting means, and the viewpoint conversion controller 5 sets the edge of the image. The detection processing may be performed, and the target position setting processing may be performed based on the processing result.

In this case, the viewpoint conversion controller 5 is constructed, for example, as shown in FIG. The viewpoint conversion controller 5 shown in FIG. 13 has the image processing unit 26 added to the viewpoint conversion controller 5 shown in FIG.
An image conversion / processing control unit 27 is provided in place of the viewpoint conversion control unit 25 of the starting point conversion controller 5 shown in FIG.

Under the control of the image conversion / processing control unit 27, the image processing unit 26 performs edge detection processing on the image data of the actual image behind the vehicle stored in the input frame buffer 21 in frame units. For example, an edge indicating a white line (line) or the like of the parking space is set as a target position, and is configured by a DSP or the like.

Further, the image conversion / processing control section 27 controls the coordinate conversion processing in the coordinate conversion processing section 22 based on the control signal Sc from the audio / visual control device 3 in the same manner as the viewpoint conversion control section 25 described above. In addition, it controls the edge detection processing in the image processing unit 26, and is composed of a CPU and the like.

When the image processing unit 26 performs edge detection processing under the control of the image conversion / processing control unit 27 and a target position is set according to the processing result, the set target position is set as a marker. A marker image shown as is generated. Then, after the marker image indicating the target position is superimposed on the image output from the coordinate conversion processing unit 22 and temporarily stored in the output frame buffer 24, analog display is performed by a D / A converter (not shown). The audio / visual control device 3 is converted into the image signal S1.
Is supplied to. Then, the display image signal S1 is selected as the selection image signal S2 to be supplied to the display 2 by the audio / visual control device 3, so that the target position automatically set in the image processing unit 26 of the viewpoint conversion controller 5 is a marker. The image behind the host vehicle, which is superimposed as an image, is displayed on the display 2.

As in this example, the viewpoint conversion controller 5
In the case where the edge detection processing is performed in step S3 and the target position is automatically set based on the processing result, the display 2 is displayed when the driver starts the backward traveling of the vehicle.
Since it is not necessary to operate the target position setting switch 9 to set the target position while referring to, it is possible to effectively avoid the inconvenience of causing the driver to feel annoyed in the operation.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of an in-vehicle system to which the present invention has been applied.

FIG. 2 is a block diagram showing an internal configuration of an audio / visual control device included in the vehicle-mounted system.

FIG. 3 is a block diagram showing an internal configuration of a viewpoint conversion controller included in the vehicle-mounted system.

FIG. 4 is a diagram for explaining viewpoint heights of an actual image, a converted image, and a plane-converted image behind the own vehicle, in which (a) shows a viewpoint of a CCD camera installed behind the own vehicle and (b) ) Indicates the viewpoint of the virtual camera A, which is assumed to be installed higher than the CCD camera, and (c) indicates the virtual camera A.
The viewpoint of the virtual camera B, which is assumed to be installed at a position higher than the above, is shown.

FIG. 5 is a diagram showing a state when the host vehicle travels backward, (a) shows a state at a stage when the host vehicle starts traveling backward, and (b) shows a state from the present position of the host vehicle to a target position. Shows the state when the distance D reaches the first viewpoint conversion distance D1, and (c) shows the state when the distance D from the current position of the vehicle to the target position reaches the second viewpoint conversion distance D2. Is shown.

6A and 6B are diagrams showing an image of the rear of the own vehicle displayed on a display, FIG. 6A shows an example of a real image of the rear of the own vehicle taken by a CCD, and FIG. 6B is a virtual camera of the rear of the own vehicle. An example of a converted image that is virtually viewed from the viewpoint of A is shown, and (c) shows an example of a plane converted image that is viewed as the rear of the vehicle is viewed from the viewpoint of the virtual camera B in a direction perpendicular to the road surface.

FIG. 7 shows the distance from the current position of the vehicle to the target position,
It is a figure which shows the relationship with the camera ground height and the depression angle of a camera optical axis.

FIG. 8 is a flowchart illustrating a flow of a series of processes in the vehicle-mounted system.

FIG. 9 is a flowchart illustrating a flow of a series of processes in the vehicle-mounted system.

FIG. 10 is a diagram showing a state in which the target position is set in the vicinity of a line on the front side of the parking space in the in-vehicle system, and FIG. 10 (a) shows a case where the vehicle is stopped parallel to the parking space. The image displayed on a display is shown, (b) has shown the image displayed on a display, when the own vehicle is diagonally stopped with respect to the parking space.

FIG. 11 is a diagram showing a state where a rectangular area indicating the entire parking space is set as a target position in the vehicle-mounted system, and FIG. 11A shows an image displayed on the display when the own vehicle is parked in parallel. 9B shows an image displayed on the display when the own vehicle is parked in parallel.

FIG. 12 is a diagram showing a state in which a target position is set on a plane conversion image behind the vehicle viewed from the viewpoint of the virtual camera B.

FIG. 13 is a block diagram showing an internal configuration of a viewpoint conversion controller in the case of automatically setting a target position in the vehicle-mounted system.

[Explanation of symbols]

1 In-vehicle system 2 display 3 Audio visual control device 4 CCD camera 5 viewpoint conversion controller 12 Control unit 15 Image switching section 16 Image composition section 22 Coordinate conversion processing unit 23a, 23b, 23c conversion table 25 Viewpoint conversion control unit 26 Image Processor 27 Image conversion / processing control unit

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) B60R 21/00 B60R 21/00 626G 628 628D 1/00 1/00 A G03B 15/00 G03B 15/00 S G06T 1 / 00 330 G06T 1/00 330A 7/60 180 7/60 180B G08G 1/16 G08G 1/16 C H04N 7/18 H04N 7/18 J F Term (reference) 5B057 AA16 BA24 CA12 CA16 CB12 CB16 CD11 CD20 CH07 CH18 DA16 DB02 DC30 DC36 5C054 CA04 CC03 EA01 FC11 FC15 FD03 FE09 GB15 HA30 5H180 AA01 CC04 CC12 FF05 FF22 FF33 LL02 LL08 5L096 BA04 CA14 CA24 DA02 FA66

Claims (11)

[Claims] 1. A camera installed at a rear part of a vehicle for capturing an image of the rear of the vehicle, and a position higher than an actual viewpoint of the camera by coordinate conversion of an actual image of the rear of the vehicle captured by the camera. A conversion image generation unit that generates a conversion image that is virtually captured as a viewpoint, a display unit that selectively displays the actual image behind the vehicle and the conversion image, and an image to be displayed on the display unit. Display control means for selecting, target position setting means for setting a target position to be a target when the vehicle is traveling backward, and distance from the current position of the vehicle to the target position set by the target position setting means The display control means is configured to display the display means when the distance to the target position calculated by the distance calculation means is less than a predetermined distance. Vehicle rear monitoring system and switches the image to be displayed to the converted image from the real image. 2. The conversion image generation means generates a plurality of conversion images having different viewpoint heights, and the display control means reduces the distance to the target position calculated by the distance calculation means. The vehicle rear monitoring device according to claim 1, wherein the converted image displayed on the display unit is sequentially switched from a converted image with a low viewpoint to a converted image with a high viewpoint. 3. The conversion image generation means generates a plane conversion image that is virtually taken as an image of the rear of the vehicle taken in a direction perpendicular to the road surface, as the conversion image having the highest viewpoint height. The vehicle rear monitoring device according to claim 2. 4. The vehicle rear monitoring apparatus according to claim 1, wherein the target position setting means sets the target position according to a user's operation input. 5. The vehicle according to claim 4, wherein the display control unit causes the display unit to display the plane-converted image when the target position is set by the target position setting unit. Rear monitoring device. 6. The target position setting means performs edge detection processing on the real image or the converted image, and sets the target position based on the processing result. 5. The vehicle rear monitoring device according to any one of 1. 7. The vehicle rear monitoring device according to claim 1, wherein the target position setting means sets a parking position of the vehicle as the target position. 8. The target position setting means sets, as the target position, the vicinity of a line on the back side of the parking position, which is the stop position of the vehicle rear end portion.
The vehicle rear monitoring device according to item 1. 9. The vehicle rear according to claim 7, wherein the target position setting means sets the vicinity of a line on the front side of the parking position, which is a stop position of the front end portion of the vehicle, as the target position. Monitoring equipment. 10. The vehicle rear monitoring according to claim 7, wherein the target position setting means sets a rectangular area of the parking position, which is a space where the entire vehicle stops, as the target position. apparatus. 11. The display control means causes the display means to display the target position set by the target position setting means by superimposing it on the actual image or the converted image. The vehicle rear monitoring device described in (1).