Rear view image display device and rear view image display method

Abstract

To easily visually recognize what kind of vehicle is running behind a vehicle.SOLUTION: A rear image display device 1 includes an imaging unit 111 that captures the rear of a vehicle V1 with a camera 21 to generate a captured image PA, a first generation unit 112 that cuts out an image from a partial area of the captured image PA to generate a first rear image P1, a tilt detection unit 113 that detects a tilt angle AN of the vehicle V1, a second generation unit that cuts out an image from another partial area of the captured image PA according to the tilt angle AN to generate a second rear image P2 that is different from the first rear image P1, and a display control unit 116 that displays the first rear image P1 and the second rear image P2 on a display 251.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a rear image display device and a rear image display method. [Background technology]

[0002] Conventionally, techniques for displaying an image behind a vehicle have been disclosed. The vehicle rear display device described in Patent Document 1 includes a camera that captures an image of the area behind the vehicle, a display processing unit that displays the image of the area behind the vehicle captured by the camera, an inclination detection unit that detects changes in the inclination of the vehicle in the longitudinal direction, and an imaging range switching unit that switches the imaging range corresponding to the display range by the display processing unit in the vertical direction while the vehicle is traveling within a predetermined range after the inclination change is detected, and then returns the imaging range to its original state when the inclination change disappears. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-150010 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with the technology described in Patent Document 1, the imaging range is switched in response to changes in the inclination of the vehicle in the longitudinal direction, which can make it difficult to visually identify what vehicles are traveling behind the vehicle. An object of the present invention is to provide a rear image display device and a rear image display method that allow a driver to easily visually recognize what vehicles are traveling behind the vehicle. [Means for solving the problem]

[0005] In order to achieve the above object, the rear image display device of the present invention includes an imaging unit that captures an image of the rear of a vehicle using a camera and generates a captured image; a first generation unit that cuts out an image from a partial area of ​​the captured image and generates a first rear image; an inclination detection unit that detects the inclination angle of the vehicle; a second generation unit that cuts out an image from another partial area of ​​the captured image in accordance with the inclination angle and generates a second rear image different from the first rear image; and a display control unit that displays the first rear image and the second rear image on a display. a distance detection unit that detects a distance between the vehicle and another vehicle traveling behind the vehicle; Equipped with If the distance is equal to or less than a threshold, the display control unit does not display the second rear image on the display.

[0006] In order to achieve the above object, the rear image display method of the present invention includes a photographing step of photographing the rear of a vehicle with a camera to generate a photographed image; a first generation step of cutting out an image from a partial area of ​​the photographed image to generate a first rear image; an inclination detection step of detecting an inclination angle of the vehicle; a second generation step of cutting out an image from another partial area of ​​the photographed image in accordance with the inclination angle to generate a second rear image different from the first rear image; and a display control step of displaying the first rear image and the second rear image on a display. Detecting a distance between the vehicle and another vehicle traveling behind the vehicle; Including fruit , If the distance is equal to or less than a threshold value, the second rear image is not displayed on the display in the display control step. [Effects of the Invention]

[0007] According to the present invention, a first rear image generated by cutting out an image from a partial area of ​​the captured image and a second rear image generated by cutting out an image from another partial area of ​​the captured image are displayed on a display, making it easy to see what vehicles are traveling behind the vehicle. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram illustrating an example of the configuration of a rear image display system and a rear image display device. [Figure 2] 3A and 3B are diagrams illustrating an example of a reference rear image, an upper rear image, and a lower rear image. [Figure 3]FIG. 4 is a diagram showing an example of a display image in a first state. [Figure 4] FIG. 10 is a diagram showing an example of a display image in a second state. [Figure 5] FIG. 10 is a diagram showing an example of a display image in a third state. [Figure 6] FIG. 10 is a diagram showing an example of a display image in a fourth state. [Figure 7] 10 is a flowchart illustrating an example of processing performed by a rear image display device. [Figure 8] 10 is a flowchart illustrating an example of processing performed by a rear image display device. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, the configuration of a rear image display system 100 and a rear image display device 1 will be described with reference to Fig. 1. Fig. 1 is a diagram showing an example of the configuration of the rear image display system 100 and the rear image display device 1. 1, the rear image display system 100 includes a rear image display device 1, a camera 21, an inclination sensor 22, a distance measurement sensor 23, an operation unit 24, and a display unit 25. The rear image display system 100 is mounted on a vehicle V1. Vehicle V1 will be described with reference to FIG.

[0010] The camera 21 captures an image of the rear of the vehicle V1 and generates a captured image PA in accordance with instructions from the rear image display device 1. The camera 21 includes an image sensor such as a CCD (Charge-Coupled Device) or a CMOS (Complementary Metal-Oxide-Semiconductor), and a data processing circuit that generates the captured image PA from the image sensor. The imaging range corresponding to the captured image PA of the camera 21 is wider than the imaging range corresponding to the rear image displayed on the display 251. The rear image is, for example, the first rear image P1. In other words, the imaging angle of view AVA indicating the imaging range corresponding to the captured image PA is larger than the reference angle of view AVT indicating the imaging range of the first rear image P1. The first rear image P1, the photographing angle of view AVA, and the reference angle of view AVT will be described with reference to FIG.

[0011] The inclination sensor 22 detects the inclination angle AN of the vehicle V1. The inclination angle AN is the angle between the front-to-rear direction of the vehicle V1 or the traveling direction D1 and the horizontal direction DH. The inclination sensor 22 includes a sensor such as an acceleration sensor or a gyro sensor, and a data processing circuit that generates the inclination angle AN from the sensor. The traveling direction D1, the horizontal direction DH, and the tilt angle AN will be described with reference to FIG.

[0012] The distance measurement sensor 23 is provided on the vehicle V1 with, for example, a LiDAR (Light Detection and Ranging) and detects the distance LD to another vehicle V2 traveling behind the vehicle V1 using electromagnetic waves. In this embodiment, the case where the distance measurement sensor 23 is a LiDAR will be described, but the distance measurement sensor 23 is not limited to this. For example, the distance measurement sensor 23 may be a radar or sonar sensor.

[0013] The operation unit 24 includes keys, switches, etc., and receives operations from a user in the vehicle V1. The user is, for example, a driver. The operation unit 24 outputs an operation signal corresponding to the received operation to the rear image display device 1. The operations received by the operation unit 24 include, for example, an operation to display the first rear image P1 as the main image PM on the display 251, an operation to display the second rear image P2 as the main image PM on the display 251, etc. The second rear image P2 and the main image PM will be described with reference to FIG.

[0014] The display unit 25 includes a display 251, and displays various images on the display 251. A liquid crystal display, an organic EL display, or the like is used as the display 251. The display unit 25 causes the display 251 to display a first rear image P1, a second rear image P2, and the like.

[0015] The rear image display device 1 is a computer including a processor 11 such as a CPU (Central Processing Unit) or an MPU (Micro-Processing Unit), and a memory 12 such as a ROM (Read Only Memory) or RAM (Random Access Memory). In addition to these devices, the rear image display device 1 also includes a storage device such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive), an interface circuit for connecting sensors and peripheral devices, an in-vehicle network communication circuit for communicating with other in-vehicle devices via an in-vehicle network, etc. The rear image display device 1 realizes various functional configurations by having the processor 11 execute a control program 121 stored in the memory 12. The rear image display device 1 is configured, for example, by an ECU (Electronic Control Unit).

[0016] In this embodiment, the rear image display device 1 is configured as an ECU, but is not limited to this. The rear image display device 1 may be a computer including a processor 11 and a memory 12. For example, the rear image display device 1 may be configured as a personal computer or a tablet terminal.

[0017] The rear image display device 1 includes an imaging unit 111, a first generation unit 112, an inclination detection unit 113, a second generation unit 114, a distance detection unit 115, a display control unit 116, an image storage unit 122, and an inclination storage unit 123. Specifically, the processor 11 executes a control program 121 stored in the memory 12, thereby functioning as the imaging unit 111, the first generation unit 112, the inclination detection unit 113, the second generation unit 114, the distance detection unit 115, and the display control unit 116. The processor 11 also executes the control program 121 stored in the memory 12, thereby causing the memory 12 to function as the image storage unit 122 and the inclination storage unit 123.

[0018] The image storage unit 122 stores the captured image PA. The captured image PA is acquired from the camera 21 by the imaging unit 111 and stored in the image storage unit 122. The captured image PA is read out by the first generation unit 112 and the second generation unit 114.

[0019] The tilt storage unit 123 stores the tilt angle AN. The tilt angle AN is acquired from the tilt sensor 22 by the tilt detection unit 113 and stored in the tilt storage unit 123. The tilt angle AN is read out by the second generation unit 114.

[0020] The imaging unit 111 captures an image of the rear of the vehicle V1 using the camera 21 to generate a captured image PA. Specifically, the imaging unit 111 acquires the captured image PA captured by the camera 21. The imaging unit 111 also stores the captured image PA in the image storage unit 122.

[0021] The first generation unit 112 generates a first rear image P1 by cutting out an image from a partial area of ​​the captured image PA. The first rear image P1 is, for example, a reference rear image PT. The reference rear image PT is an image cut out from a central area of ​​the captured image PA. The reference rear image PT will be further described with reference to FIG.

[0022] The inclination detection unit 113 detects the inclination angle AN of the vehicle V1. Specifically, the inclination detection unit 113 acquires the inclination angle AN detected by the inclination sensor 22. The inclination detection unit 113 stores the inclination angle AN in the inclination storage unit 123.

[0023] The second generation unit 114 generates a second rear image P2 different from the first rear image P1 by cutting out an image from another part of the captured image PA in accordance with the inclination angle AN. The second rear image P2 includes an upper rear image PU and a lower rear image PD. The upper rear image PU is an image of the upper rear of the vehicle V1 from the captured image PA. The lower rear image PD is an image of the lower rear of the vehicle V1 from the captured image PA. The upper rear image PU and the lower rear image PD will be further described with reference to FIG.

[0024] Specifically, the second generation unit 114 generates the upper rear image PU or the lower rear image PD as the second rear image P2 in accordance with the state determined by the display control unit 116. The states determined by the display control unit 116 are the first state ST1 to the fourth state ST4. The relationship between the first state ST1 to the fourth state ST4 and the images generated by the second generating unit 114 will be described with reference to FIGS.

[0025] The distance detection unit 115 detects the distance LD between the vehicle V1 and another vehicle V2 traveling behind the vehicle V1. Specifically, the distance detection unit 115 acquires the distance LD from the distance measurement sensor 23.

[0026] The display control unit 116 displays the first rear image P1 and the second rear image P2 on the display 251. Specifically, the display control unit 116 displays a main image PM in a first area AR1 of the display area AR of the display 251, and a sub-image PS in a second area AR2 of the display area AR that is smaller than the first area AR1. The display control unit 116 also displays one of the first rear image P1 and the second rear image P2 as the main image PM, and displays the other of the first rear image P1 and the second rear image P2 as the sub-image PS. The first area AR1 and the second area AR2 will be further described with reference to FIGS.

[0027] For example, the display control unit 116 displays a first rear image P1 as a main image PM in a first area AR1 of the display area AR of the display 251, and displays a second rear image P2 as a sub-image PS in a second area AR2 of the display area AR of the display 251. Furthermore, for example, the display control unit 116 displays a second rear image P2 as a main image PM in the first area AR1 of the display area AR of the display 251, and displays the first rear image P1 as a sub-image PS in the second area AR2 of the display area AR of the display 251.

[0028] Furthermore, for example, the display control unit 116 displays the main image PM in the entire display area AR of the display 251. An area of ​​the main image PM that does not include an image of a vehicle is determined to be the second area AR2. Then, the sub-image PS is displayed in the second area AR2.

[0029] Furthermore, the display control unit 116 determines whether the first rear image P1 or the second rear image P2 is to be displayed as the main image PM in the first area AR1, for example, in accordance with a change in the inclination angle AN over time. The display control unit 116 determines whether the vehicle V1 is in the first state ST1, the second state ST2, the third state ST3, or the fourth state ST4, for example, depending on the change in the inclination angle AN over time. The first state ST1 is a state in which the vehicle V1 has entered an uphill slope RU from a substantially horizontal first road R1. The second state ST2 is a state in which the vehicle V1 has entered a substantially horizontal second road R2 from an uphill slope RU. The third state ST3 is a state in which the vehicle V1 has entered a downhill slope RD from a substantially horizontal second road R2. The fourth state ST4 is a state in which the vehicle V1 has entered a substantially horizontal third road R3 from a downhill slope RD. The first state ST1 to the fourth state ST4 will be further described with reference to FIGS.

[0030] Furthermore, when the distance LD detected by the distance detection unit 115 is equal to or less than a threshold value LS, the display control unit 116 does not display the second rear image P2 on the display 251. The threshold value LS is, for example, 10 m. In this case, the display control unit 116 displays only the first rear image P1 in the entire display area AR of the display 251. The threshold value LS may be set according to the traveling speed of the vehicle V1. For example, it is preferable to increase the threshold value LS as the traveling speed of the vehicle V1 increases. Furthermore, for example, the threshold value LS may be set in accordance with the change in the tilt angle AN over time. It is preferable that the threshold value LS be set shorter as the change in the tilt angle AN over time increases.

[0031] In this embodiment, a case will be described in which the display control unit 116 determines which of the first rear image P1 and the second rear image P2 to display as the main image PM in the first area AR1 in accordance with a change in the inclination angle AN over time. However, the present invention is not limited to this. The display control unit 116 may also determine which of the first rear image P1 and the second rear image P2 to display as the main image PM in the first area AR1 in accordance with, for example, a user's operation on the operation unit 24.

[0032] In this embodiment, a case will be described in which the display control unit 116 displays a main image PM in a first area AR1 of the display area AR of the display 251 and a sub-image PS in a second area AR2 of the display area AR that is smaller than the first area AR1, but this is not limiting. The display control unit 116 may display a first rear image P1 and a second rear image P2 on the display 251. For example, the display control unit 116 may divide the display area AR of the display 251 into two equal parts, display the first rear image P1 in one display area, and display the second rear image P2 in the other display area. For example, the display control unit 116 may divide the display area AR of the display 251 into two equal parts, a right display area and a left display area, and display the first rear image P1 in the right display area and the second rear image P2 in the left display area.

[0033] Next, the reference rear image PT, the upper rear image PU, and the lower rear image PD will be described with reference to Fig. 2. Fig. 2 is a diagram showing an example of the reference rear image PT, the upper rear image PU, and the lower rear image PD. FIG. 2 shows a side view 301 illustrating an example of a change in the inclination angle AN of the road on which the vehicle V1 is traveling, and an image diagram 400 illustrating an example of a captured image PA captured by the camera 21.

[0034] The side view 301 shows a vehicle V1 traveling in a traveling direction D1, and a vehicle V2 traveling behind the vehicle V1 in a traveling direction D2. The vehicle V1 is entering an uphill slope RU from a substantially horizontal first road R1. In other words, the side view 301 shows that the vehicle V1 is in a first state ST1. The uphill slope RU is laid so as to connect the substantially horizontal first road R1 and the substantially horizontal second road R2. The inclination angle AN of the vehicle V1 is the angle between the traveling direction D1 of the vehicle V1 and the horizontal direction DH. The inclination angle AN is detected by the inclination sensor 22. The distance LD is the distance between the vehicle V1 and the vehicle V2. The distance LD is detected by the distance measurement sensor 23. Vehicle V2 corresponds to an example of an "other vehicle."

[0035] A camera 21 is disposed at the rear of the vehicle V1. The imaging angle of view AVA indicated by the dashed line indicates the imaging range in the vertical direction of the camera 21. The imaging angle of view AVA is, for example, 90 degrees. The reference angle of view AVT, indicated by a dashed line, indicates the vertical imaging range of the camera 21 corresponding to the reference rear image PT. The upper angle of view AVU, indicated by a dashed line, indicates the vertical imaging range of the camera 21 corresponding to the upper rear image PU. The lower angle of view AVD, indicated by a dashed line, indicates the vertical imaging range of the camera 21 corresponding to the lower rear image PD. Each of the reference angle of view AVT, upper angle of view AVU, and lower angle of view AVD is, for example, 45 degrees.

[0036] The image diagram 400 depicts a captured image PA. The captured image PA includes a vehicle image PV2 and a vehicle image PV3. The vehicle image PV2 is an image of a vehicle V2. The vehicle image PV3 is an image of a vehicle V3. The vehicle V3 is traveling in the opposite lane to the lane in which the vehicles V1 and V2 are traveling.

[0037] The image diagram 400 shows a solid rectangular imaging angle of view AVA, a dashed rectangular reference angle of view AVT, a dashed rectangular upper angle of view AVU, and a dashed rectangular lower angle of view AVD. The upper angle of view AVU is positioned at the top of the imaging angle of view AVA. The reference angle of view AVT is positioned at the center of the imaging angle of view AVA in the vertical direction. The lower angle of view AVD is positioned at the bottom of the imaging angle of view AVA. Furthermore, the upper angle of view AVU, the reference angle of view AVT, and the lower angle of view AVD are each positioned at the center of the imaging angle of view AVA in the horizontal direction.

[0038] The captured image PA of the camera 21 is an image within the capture angle of view AVA shown in the image diagram 400. In the image diagram 400, the reference angle of view AVT indicates the capture range of the reference rear image PT, the upper angle of view AVU indicates the capture range of the upper rear image PU, and the lower angle of view AVD indicates the capture range of the lower rear image PD. The first generation unit 112 cuts out a reference rear image PT from the center region in the vertical direction corresponding to the reference angle of view AVT in the captured image PA, and generates the reference rear image PT as a first rear image P1. The second generation unit 114 cuts out an upper rear image PU from an upper region of the captured image PA that corresponds to the upper angle of view AVU, and generates the upper rear image PU as the second rear image P2. The second generation unit 114 also cuts out a lower rear image PD from a lower region of the captured image PA that corresponds to the lower angle of view AVD, and generates the lower rear image PD as the second rear image P2. The central area of ​​the captured image PA, which corresponds to the reference angle of view AVT, corresponds to an example of a "partial area." In the captured image PA, the upper region corresponding to the upper angle of view AVU and the lower region corresponding to the lower angle of view AVD each correspond to an example of "another part of the region."

[0039] Next, a display image displayed on the display 251 will be described with reference to Figures 3 to 6. In this embodiment, a case where a landscape rearview display is used as the display 251 will be described.

[0040] 3 is a diagram showing an example of a display image in the first state ST1. An example of a conventional side view 310 and an image view 510 is shown in the upper part of FIG. As shown in the side view 310, the reference rear image PT is generated by cutting out the central area corresponding to the reference angle of view AVT from the imaging range corresponding to the captured image PA of the camera 21. Furthermore, as shown in image diagram 510, the reference rear image PT is displayed in the entire display area AR of the display 251. The reference rear image PT includes a vehicle image PV2 and a vehicle image PV3. A mark MV indicates the vehicle image PV2. As shown in image diagram 510, the lower part of the vehicle image PV2 is displayed on the display 251.

[0041] The bottom of FIG. 3 shows an example of a side view 311 and an image view 511 of this embodiment. As shown in side view 311, first generation unit 112 cuts out a reference rear image PT from a central region corresponding to a reference angle of view AVT from the imaging range corresponding to image PA captured by camera 21, and generates reference rear image PT as first rear image P1. Second generation unit 114 cuts out an upper rear image PU from an upper region corresponding to an upper angle of view AVU from the imaging range corresponding to image PA captured by camera 21, and generates upper rear image PU as second rear image P2.

[0042] Furthermore, as shown in image diagram 511, the display control unit 116 sets a first area AR1 and a second area AR2 in the display area AR of the display 251. In this embodiment, the second area AR2 is located in the upper right corner of the display area AR. The first area AR1 is larger than the second area AR2 and is the area of ​​the display area AR other than the second area AR2. The display control unit 116 displays the upper rear image PU as the main image PM in the first area AR1, and displays the reference rear image PT as the sub-image PS in the second area AR2. For example, when the upper rear image PU is displayed as the main image PM in the entire display area AR of the display 251, the second area AR2 is set to an area in the upper rear image PU that does not include an image of the vehicle.

[0043] The upper rear image PU displayed in the first area AR1 of the image diagram 511 displays the entire vehicle image PV2. An upward shooting mark MU is also displayed in the first area AR1 of the image diagram 511. The upward shooting mark MU indicates that the upper rear image PU is displayed in the first area AR1. The second image display mark MP2 is a thick line arranged around the periphery of the first area AR1. The second image display mark MP2 indicates that the second rear image P2 is displayed in the first area AR1.

[0044] As shown in image diagram 511, the upper rear image PU displayed in the first area AR1 displays the entire vehicle image PV2, so the user can easily see what kind of vehicle V2 is traveling behind vehicle V1.

[0045] 4 is a diagram showing an example of a display image in the second state ST2. An example of a conventional side view 320 and an image view 520 is shown in the upper part of FIG. The side view 320 shows a vehicle V1 and a vehicle V2 traveling behind the vehicle V1 in a traveling direction D2. The vehicle V1 is entering a substantially horizontal second road R2 from an uphill slope RU. In other words, the side view 320 shows that the vehicle V1 is in a second state ST2.

[0046] As shown in the side view 320, the reference rear image PT is generated by cutting out the central area corresponding to the reference angle of view AVT from the imaging range corresponding to the captured image PA of the camera 21. Furthermore, as shown in image diagram 520, the reference rear image PT is displayed in the entire display area AR of the display 251. The reference rear image PT includes a vehicle image PV2 and a vehicle image PV3. A mark MV indicates the vehicle image PV2. As shown in image diagram 520, the upper part of the vehicle image PV2 is displayed on the display 251.

[0047] The bottom of FIG. 4 shows an example of a side view 321 and an image view 521 of this embodiment. As shown in side view 321, the first generation unit 112 cuts out a reference rear image PT from a central region corresponding to the reference angle of view AVT from the imaging range corresponding to the captured image PA of camera 21, and generates a reference rear image PT as a first rear image P1. The second generation unit 114 cuts out a lower rear image PD from a lower region corresponding to the lower angle of view AVD from the imaging range corresponding to the captured image PA of camera 21, and generates a lower rear image PD as a second rear image P2.

[0048] Furthermore, as shown in the image diagram 521, the display control unit 116 sets a first area AR1 and a second area AR2 in the display area AR of the display 251. The display control unit 116 displays the reference rear image PT as the main image PM in the first area AR1, and displays the lower rear image PD as the sub-image PS in the second area AR2. For example, when the reference rear image PT is displayed as the main image PM in the entire display area AR of the display 251, the second area AR2 is set to an area in the reference rear image PT that does not include an image of the vehicle.

[0049] The entire vehicle image PV2 is displayed in the lower rear image PD displayed in the second area AR2 of the image diagram 521. A downward shooting mark MD is also displayed in the second area AR2 of the image diagram 521. The downward shooting mark MD indicates that the lower rear image PD is displayed in the second area AR2. The second image display mark MP2 is a thick line arranged around the second area AR2. The second image display mark MP2 indicates that the second rear image P2 is displayed in the second area AR2.

[0050] As shown in image diagram 521, the lower rear image PD displayed in the second area AR2 displays the entire vehicle image PV2, so the user can easily see what kind of vehicle V2 is traveling behind vehicle V1.

[0051] 5 is a diagram showing an example of a display image in the third state ST3. An example of a conventional side view 330 and an image view 530 is shown in the upper part of FIG. The side view 330 shows a vehicle V1 and a vehicle V2 traveling behind the vehicle V1 in a traveling direction D2. The vehicle V1 is entering a downhill slope RD from a substantially horizontal second road R2. That is, the side view 330 shows that the vehicle V1 is in a third state ST3.

[0052] As shown in the side view 330, the reference rear image PT is generated by cutting out the central area corresponding to the reference angle of view AVT from the imaging range corresponding to the captured image PA of the camera 21. Furthermore, as shown in image diagram 530, the reference rear image PT is displayed on the display 251. The reference rear image PT includes a vehicle image PV2 and a vehicle image PV3. A mark MV indicates the vehicle image PV2. As shown in image diagram 530, the upper part of the vehicle image PV2 is displayed on the display 251.

[0053] The bottom of FIG. 5 shows an example of a side view 331 and an image view 531 of this embodiment. As shown in side view 331, the first generation unit 112 cuts out a reference rear image PT from a central region corresponding to the reference angle of view AVT from the imaging range corresponding to the captured image PA of camera 21, and generates a reference rear image PT as a first rear image P1. The second generation unit 114 cuts out a lower rear image PD from a lower region corresponding to the lower angle of view AVD from the imaging range corresponding to the captured image PA of camera 21, and generates a lower rear image PD as a second rear image P2.

[0054] Furthermore, as shown in the image diagram 531, the display control unit 116 sets a first area AR1 and a second area AR2 in the display area AR of the display 251. The display control unit 116 displays the reference rear image PT as the main image PM in the first area AR1, and displays the lower rear image PD as the sub-image PS in the second area AR2. For example, when the reference rear image PT is displayed as the main image PM in the entire display area AR of the display 251, the second area AR2 is set to an area in the reference rear image PT that does not include an image of the vehicle.

[0055] The entire vehicle image PV2 is displayed in the lower rear image PD displayed in the second area AR2 of the image diagram 531. A downward shooting mark MD is also displayed in the second area AR2 of the image diagram 531. The downward shooting mark MD indicates that the lower rear image PD is displayed in the second area AR2. The second image display mark MP2 is a thick line arranged around the second area AR2. The second image display mark MP2 indicates that the second rear image P2 is displayed in the second area AR2.

[0056] As shown in image diagram 531, the lower rear image PD displayed in the second area AR2 displays the entire vehicle image PV2, so the user can easily see what kind of vehicle V2 is traveling behind vehicle V1.

[0057] 6 is a diagram showing an example of a display image in the fourth state ST4. An example of a conventional side view 340 and an image view 540 is shown in the upper part of FIG. The side view 340 shows a vehicle V1 and a vehicle V2 traveling behind the vehicle V1 in a traveling direction D2. The vehicle V1 is entering a substantially horizontal third road R3 from a downhill slope RD. That is, the side view 340 shows that the vehicle V1 is in a fourth state ST4.

[0058] As shown in the side view 340, the reference rear image PT is generated by cutting out the central area corresponding to the reference angle of view AVT from the imaging range corresponding to the captured image PA of the camera 21. Furthermore, as shown in image diagram 540, the display 251 displays a reference rear image PT as a first rear image P1. The reference rear image PT includes a vehicle image PV2 and a vehicle image PV3. A mark MV indicates the vehicle image PV2. As shown in image diagram 540, the display 251 displays the lower part of the vehicle image PV2.

[0059] The bottom of FIG. 6 shows an example of a side view 341 and an image view 541 of this embodiment. As shown in side view 341, the first generation unit 112 cuts out a reference rear image PT from a central region corresponding to the reference angle of view AVT from the imaging range corresponding to the captured image PA of the camera 21, and generates a reference rear image PT as a first rear image P1. The second generation unit 114 cuts out an upper rear image PU from an upper region corresponding to the upper angle of view AVU from the imaging range corresponding to the captured image PA of the camera 21, and generates an upper rear image PU as a second rear image P2.

[0060] Furthermore, as shown in the image diagram 541, the display control unit 116 sets a first area AR1 and a second area AR2 in the display area AR of the display 251. The display control unit 116 displays the upper rear image PU as the main image PM in the first area AR1, and displays the reference rear image PT as the sub-image PS in the second area AR2. For example, when the upper rear image PU is displayed as the main image PM in the entire display area AR of the display 251, the second area AR2 is set to an area in the upper rear image PU that does not include an image of the vehicle.

[0061] The entire vehicle image PV2 is displayed in the upper rear image PU displayed in the first area AR1 of the image diagram 541. An upward shooting mark MU is also displayed in the first area AR1 of the image diagram 541. The upward shooting mark MU indicates that the upper rear image PU is displayed in the first area AR1. The second image display mark MP2 is a thick line arranged around the periphery of the first area AR1. The second image display mark MP2 indicates that the second rear image P2 is displayed in the first area AR1.

[0062] As shown in image diagram 541, the upper rear image PU displayed in the first area AR1 displays the entire vehicle image PV2, so the user can easily see what kind of vehicle V2 is traveling behind vehicle V1.

[0063] As explained with reference to Figures 3 to 6, the display 251 displays a first rear image P1 and a second rear image P2 that is different from the first rear image P1, so that the user can easily see what kind of vehicle V2 is traveling behind the vehicle V1.

[0064] 3 to 6, the second area AR2 is located in the upper right corner of the display area AR of the display 251, but the present invention is not limited to this. When the main image PM is displayed in the entire display area AR of the display 251, the second area AR2 is preferably an area in the main image PM that does not include an image of a vehicle. In this case, by displaying the sub-image PS in the second area AR2, the image of the vehicle in the main image PM is not hidden by the sub-image PS. This improves the visibility of the main image PM.

[0065] Next, the processing of the rear image display device 1 will be described with reference to Fig. 7 and Fig. 8. Fig. 7 and Fig. 8 are flowcharts showing an example of the processing of the rear image display device 1. First, as shown in FIG. 7, in step S101, the imaging unit 111 captures an image of the area behind the vehicle V1 using the camera 21 to generate a captured image PA. Next, in step S103, the first generation unit 112 cuts out an image from a partial area of ​​the captured image PA to generate a first rear image P1. The first rear image P1 is, for example, a reference rear image PT. Next, in step S105, the inclination detection unit 113 detects the inclination angle AN of the vehicle V1.

[0066] Next, in step S107, the distance detection unit 115 detects the distance LD between the vehicle V1 and another vehicle V2 traveling behind the vehicle V1. Next, in step S109, the display control unit 116 determines whether the distance LD is greater than a threshold value LS. If the display control unit 116 determines that the distance LD is not greater than the threshold value LS (step S109; NO), the process proceeds to step S111. Then, in step S111, the display control unit 116 displays the first rear image P1, that is, the reference rear image PT, in the entire display area AR of the display 251. After that, the process returns to step S101. If the display control unit 116 determines that the distance LD is greater than the threshold value LS (step S109; YES), the process proceeds to step S113 in FIG.

[0067] 8, the display control unit 116 determines whether the vehicle V1 is in a first state ST1 based on the change in the inclination angle AN over time. The first state ST1 is a state in which the vehicle V1 has entered an uphill slope RU from a substantially horizontal first road R1. If the display control unit 116 determines that the vehicle V1 is not in the first state ST1 (step S113; NO), the process proceeds to step S121. If the display control unit 116 determines that the vehicle V1 is in the first state ST1 (step S113; YES), the process proceeds to step S115. Then, in step S115, the second generation unit 114 cuts out the upper rear image PU from the captured image PA to generate the upper rear image PU as the second rear image P2. Next, in step S117, the display control unit 116 sets the second rear image P2 as the main image PM. Next, in step S119, the display control unit 116 composites the first rear image P1 as a sub-image PS with the main image PM. That is, the display control unit 116 composites the main image PM and the sub-image PS, with the upper rear image PU, which is the second rear image P2, as the main image PM and the first rear image P1 as the sub-image PS, to generate a display image. Then, the display control unit 116 displays the generated display image on the display 251. Thereafter, the process returns to step S101 in FIG. 7.

[0068] If the answer to step S113 is NO, i.e., if the display control unit 116 determines that the vehicle V1 is not in the first state ST1, then in step S121, the display control unit 116 determines whether the vehicle V1 is in a second state ST2 based on the change in the inclination angle AN over time. The second state ST2 is a state in which the vehicle V1 has entered a substantially horizontal second road R2 from an uphill slope RU. If the display control unit 116 determines that the vehicle V1 is not in the second state ST2 (step S121; NO), the process proceeds to step S129. If the display control unit 116 determines that the vehicle V1 is in the second state ST2 (step S121; YES), the process proceeds to step S123. Then, in step S123, the second generation unit 114 cuts out the lower rear image PD from the captured image PA to generate the lower rear image PD as the second rear image P2. Next, in step S125, the display control unit 116 sets the first rear image P1 as the main image PM. Next, in step S127, the display control unit 116 composites the second rear image P2 as a sub-image PS with the main image PM. That is, the display control unit 116 composites the main image PM with the sub-image PS, using the first rear image P1 as the main image PM and the lower rear image PD, which is the second rear image P2, as the sub-image PS, to generate a display image. Then, the display control unit 116 displays the generated display image on the display 251. Thereafter, the process returns to step S101 in FIG. 7.

[0069] If the answer to step S121 is NO, i.e., if the display control unit 116 determines that the vehicle V1 is not in the second state ST2, then in step S129, the display control unit 116 determines whether the vehicle V1 is in a third state ST3 based on the change in the inclination angle AN over time. The third state ST3 is a state in which the vehicle V1 has entered a downhill slope RD from the substantially horizontal second road R2. If the display control unit 116 determines that the vehicle V1 is not in the third state ST3 (step S129; NO), the process proceeds to step S137. If the display control unit 116 determines that the vehicle V1 is in the third state ST3 (step S129; YES), the process proceeds to step S131. Then, in step S131, the second generation unit 114 cuts out the lower rear image PD from the captured image PA to generate the lower rear image PD as the second rear image P2. Next, in step S133, the display control unit 116 sets the first rear image P1 as the main image PM. Next, in step S135, the display control unit 116 composites the second rear image P2 as a sub-image PS with the main image PM. That is, the display control unit 116 composites the main image PM with the sub-image PS, with the first rear image P1 as the main image PM and the lower rear image PD, which is the second rear image P2, as the sub-image PS, to generate a display image. Then, the display control unit 116 displays the generated display image on the display 251. Thereafter, the process returns to step S101 in FIG. 7.

[0070] If the answer to step S129 is NO, i.e., if the display control unit 116 determines that the vehicle V1 is not in the third state ST3, then in step S137, the display control unit 116 determines whether the vehicle V1 is in a fourth state ST4 based on the change in the inclination angle AN over time. The fourth state ST4 is a state in which the vehicle V1 has entered a substantially horizontal third road R3 from a downhill slope RD. If the display control unit 116 determines that the vehicle V1 is not in the fourth state ST4 (step S137; NO), the process proceeds to step S145. Then, in step S145, the display control unit 116 displays the first rear image P1 in the entire display area AR of the display 251. After that, the process returns to step S101. If the display control unit 116 determines that the vehicle V1 is in the fourth state ST4 (step S137; YES), the process proceeds to step S139. Then, in step S139, the second generation unit 114 cuts out the upper rear image PU from the captured image PA to generate the upper rear image PU as the second rear image P2. Next, in step S141, the display control unit 116 sets the second rear image P2 as the main image PM. Next, in step S143, the display control unit 116 composites the first rear image P1 as a sub-image PS with the main image PM. That is, the display control unit 116 composites the main image PM and the sub-image PS, with the upper rear image PU, which is the second rear image P2, as the main image PM and the first rear image P1 as the sub-image PS, to generate a display image. Then, the display control unit 116 displays the generated display image on the display 251. Thereafter, the process returns to step S101 in FIG. 7.

[0071] Step S101 corresponds to an example of a "photographing step." Step S103 corresponds to an example of a "first generating step." Step S105 corresponds to an example of a "tilt detecting step." Furthermore, step S115, step S123, step S131, and step S139 correspond to an example of a "second generating step." Furthermore, step S119, step S127, step S135, and step S143 correspond to an example of a "display control step."

[0072] 7 and 8, the display control unit 116 determines whether the vehicle V1 is in any one of the first state ST1, the second state ST2, the third state ST3, and the fourth state ST4, for example, in accordance with a change in the inclination angle AN over time. Then, the second generation unit 114 generates an upper rear image PU or a lower rear image PD as the second rear image P2 in accordance with the state determined by the display control unit 116. The display control unit 116 displays the first rear image P1 and the second rear image P2 on the display 251. Therefore, the display control unit 116 generates either the upper rear image PU or the lower rear image PD as the second rear image P2 depending on the state determined by the display control unit 116, and therefore the upper rear image PU or the lower rear image PD can be appropriately generated and displayed as the second rear image P2. Therefore, it is possible to easily visually recognize what kind of vehicle V2 is traveling behind the vehicle V1.

[0073] As described above with reference to Figures 1 to 8, the rear image display device 1 of this embodiment includes an imaging unit 111 that captures an image of the rear of the vehicle V1 using the camera 21 to generate a captured image PA, a first generation unit 112 that cuts out an image from a partial area of ​​the captured image PA to generate a first rear image P1, an inclination detection unit 113 that detects the inclination angle AN of the vehicle V1, a second generation unit that cuts out an image from another partial area of ​​the captured image PA in accordance with the inclination angle AN to generate a second rear image P2 that is different from the first rear image P1, and a display control unit 116 that displays the first rear image P1 and the second rear image P2 on the display 251.

[0074] That is, an image is cut out from a partial area of ​​the captured image PA to generate a first rear image P1, and an image is cut out from another partial area of ​​the captured image PA in accordance with the inclination angle AN to generate a second rear image P2 different from the first rear image P1. Then, the first rear image P1 and the second rear image P2 are displayed on the display 251. Therefore, since the second rear image P2 is generated by cutting out an image from another part of the captured image PA in accordance with the tilt angle AN, the second rear image P2 can be generated by cutting out an appropriate area of ​​the captured image PA. Furthermore, since the first rear image P1 and the second rear image P2 are displayed on the display 251, it is easy to visually recognize what kind of vehicle V2 is traveling behind the vehicle V1.

[0075] It also includes a distance detection unit 115 that detects the distance LD between the vehicle V1 and another vehicle V2 traveling behind the vehicle V1, and if the distance LD is equal to or less than a threshold value LS, the display control unit 116 does not display the second rear image P2 on the display 251. In other words, when the distance LD is equal to or less than the threshold value LS, only the first rear image P1 is displayed in the entire display area AR of the display 251. For example, the threshold value LS is set so that the vehicle image PV2 is included in the first rear image P1 when the distance LD is equal to or less than the threshold value LS. Therefore, since the vehicle image PV2 is included in the first rear image P1, by displaying only the first rear image P1 in the entire display area AR of the display 251, it is possible to easily visually recognize what kind of vehicle V2 is traveling behind the vehicle V1.

[0076] In addition, the display control unit 116 displays a main image PM in a first area AR1 of the display area AR of the display 251 and a sub-image PS in a second area AR2 of the display area AR that is narrower than the first area AR1, and displays one of the first rear image P1 and the second rear image P2 as the main image PM and the other of the first rear image P1 and the second rear image P2 as the sub-image PS. That is, one of the first rear image P1 and the second rear image P2 is displayed as the main image PM, and the other of the first rear image P1 and the second rear image P2 is displayed as the sub-image PS. Therefore, by appropriately determining the main image PM and the sub-image PS, it is possible to easily visually recognize what kind of vehicle V2 is traveling behind the vehicle V1.

[0077] Furthermore, the display control unit 116 displays the main image PM in the entire display area AR of the display 251, sets the area of ​​the main image PM that does not include the image of the vehicle as the second area AR2, and displays the sub-image PS in the second area. Therefore, an area in the main image PM that does not include an image of a vehicle is set as the second area AR2, so that the second area AR2 can be determined appropriately.

[0078] In addition, the rear image display method of this embodiment includes a photographing step of photographing the rear of the vehicle V1 using the camera 21 to generate a photographed image PA, a first generation step of cutting out an image from a partial area of ​​the photographed image PA to generate a first rear image P1, an inclination detection step of detecting the inclination angle AN of the vehicle V1, a second generation step of cutting out an image from another partial area of ​​the photographed image PA according to the inclination angle AN to generate a second rear image P2 different from the first rear image P1, and a display control step of displaying the first rear image P1 and the second rear image P2 on the display 251. Therefore, the rear image display method of this embodiment has the same effects as the rear image display device 1 of this embodiment.

[0079] The above-described embodiment is merely an example of one embodiment of the present invention, and any modifications and applications are possible without departing from the spirit of the present invention.

[0080] For example, in order to facilitate understanding of the present invention, the components are classified according to their main processing contents in Fig. 1, but the components can be further classified into more components according to the processing contents, or one component can be classified to perform more processes. The processing of each component may be executed by a single piece of hardware or by multiple pieces of hardware, and the processing of each component may be realized by a single program or by multiple programs.

[0081] In addition, in FIG. 1, the rear image display device 1 may be provided with at least one of the tilt sensor 22, the operation unit 24, and the display unit 50 as an integral unit.

[0082] In the present embodiment, the display control unit 116 determines whether the vehicle V1 is in any of the first state ST1 to the fourth state ST4, for example, in accordance with a change in the inclination angle AN over time, but is not limited to this. The second generation unit 114 may generate the upper rear image PU or the lower rear image PD as the second rear image P2 in accordance with the inclination angle AN.

[0083] Furthermore, when the obstacle display method of the present invention is realized using a computer, the control program 121 executed by the computer can be configured in the form of a recording medium or a transmission medium for transmitting the control program 121. The recording medium may be a magnetic or optical recording medium or a semiconductor memory device. Specific examples include portable or fixed recording media such as a flexible disk, HDD, CD-ROM (Compact Disk Read Only Memory), DVD, Blu-ray (registered trademark) Disc, magneto-optical disk, flash memory, and card-type recording medium. The recording medium may also be a non-volatile storage device such as RAM, ROM, or HDD provided in the rear image display device 1. The control program 121 may be downloaded by the rear image display device 1 from a server device communicably connected to the rear image display device 1 via a network.

[0084] 7 and 8 are divided according to the main processing content to facilitate understanding of the processing of the rear image display device 1, and the present invention is not limited by the way in which the processing units are divided or the names of the processing units. The processing of the rear image display device 1 may be divided into more processing units according to the processing content. Furthermore, the processing of the rear image display device 1 may be divided so that one processing unit includes more processes. [Explanation of symbols]

[0085] 100 Rear image display system 1 Rear image display device 11 processors 111 Imaging unit 112 1st generation part 113 Tilt detection unit 114 Second generation part 115 Distance detection unit 116 Display control unit 12 Memory 121 Control Program 122 Image storage unit 123 Tilt memory section 21 Camera 22 Inclination sensor 23 Distance measurement sensor 24 Control section 25 Display section 251 Display AN Tilt angle AR1 1st area AR2 2nd area AVA shooting angle MD downward shooting mark MU upward shooting mark P1 1st rear image P2 Second rear image PA photographed image PM Main Image PS sub-image V1, V2, V3 vehicles

Claims

1. an imaging unit that captures an image of the rear of the vehicle using a camera and generates a captured image; a first generation unit that generates a first rear image by cutting out an image from a partial area of ​​the captured image; an inclination detection unit that detects an inclination angle of the vehicle; a second generation unit that generates a second rear image different from the first rear image by cutting out an image from another partial region of the captured image according to the tilt angle; a display control unit that displays the first rear image and the second rear image on a display; a distance detection unit that detects a distance between the vehicle and another vehicle traveling behind the vehicle; Equipped with When the distance is equal to or less than a threshold, the display control unit does not display the second rear image on the display.

2. The display control unit a main image to be displayed in a first area of ​​a display area of ​​the display, and a sub-image to be displayed in a second area of ​​the display area that is smaller than the first area; displaying one of the first rear image and the second rear image as the main image; the other of the first rearward image and the second rearward image is displayed as the sub-image. The rear image display device according to claim 1 .

3. The display control unit Displaying the main image over the entire display area of ​​the display; an area of ​​the main image that does not include an image of a vehicle is set as the second area; displaying the sub-image in the second area; The rear image display device according to claim 2 .

4. a photographing step of photographing the rear of the vehicle with a camera to generate a photographed image; a first generation step of generating a first rear image by cutting out an image from a partial region of the captured image; an inclination detection step of detecting an inclination angle of the vehicle; a second generation step of generating a second rear image different from the first rear image by cutting out an image from another partial region of the captured image according to the tilt angle; a display control step of displaying the first rear image and the second rear image on a display; Detecting a distance between the vehicle and another vehicle traveling behind the vehicle; Including, When the distance is equal to or less than a threshold, the second rear image is not displayed on the display in the display control step.

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