Rear image recording device for vehicle

Abstract

To provide a rear image recording device which is improved so as to increase such a possibility that a driver of a following vehicle is imaged and recorded in such a state that the following vehicle excessively gets close to the own vehicle in comparison to a conventional technique.SOLUTION: A vehicle rear image recording device comprises: a rear camera as an imaging unit which images the rear side of the own vehicle; a cut-out control unit (S90) which cuts out a prescribed range of an image captured by the imaging unit; a storage as a recording unit which records the image cut out by the cut-out control unit; a determination unit (S20) which determines whether or not there is the following vehicle in the captured image; and a change unit (S60) which changes the upper edge of the prescribed range to the upper side with respect to the captured image such that the reference position falls within the prescribed range when it is determined that the reference position of the following vehicle determined by the determination unit is located on the upper side of the prescribed range (S40).SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a rear image recording device for a vehicle such as an automobile. [Background technology]

[0002] As one of image recording devices for vehicles such as automobiles, a rear image recording device that records an image behind the vehicle is known. For example, the following Patent Document 1 describes a rear image recording device that detects tailgating by a following vehicle based on the distance between the vehicle and the following vehicle, and records an image behind the vehicle when tailgating by the following vehicle is detected. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-205078 A Summary of the Invention

[0004] [Problem to be solved by the invention] In a rear image recording device, it is known that, instead of using a dedicated camera to obtain an image behind the vehicle, an image taken by a camera for driving assistance of the vehicle is processed to produce an image for recording. However, since the angle of view of the camera for driving assistance is not wide, if a following vehicle approaches the vehicle excessively, especially if the following vehicle is a large truck, the driver will be out of the angle of view of the camera above, and the driver will not be able to be photographed and recorded.

[0005] To address this issue, it is conceivable to equip the vehicle with a camera with a small angle of view and a camera with a large angle of view, and use the two cameras depending on the distance between the vehicle and the following vehicle. However, in this case, since two cameras are required, the rear image recording device becomes more expensive than when there is only one camera.

[0006] In addition, a following vehicle photographed by a camera with a small angle of view is perceived to be farther away from the vehicle than a following vehicle photographed by a camera with a large angle of view. Therefore, when the monitor image displayed on the display is switched by using different cameras, the perceived distance of the following vehicle from the vehicle changes suddenly, and the occupants of the vehicle inevitably feel uncomfortable.

[0007] To provide an improved rear image recording device that increases the possibility of photographing and recording the driver of a following vehicle in a situation where the following vehicle approaches the vehicle excessively, while avoiding the rear image recording device becoming expensive and passengers feeling uncomfortable.

[0008] [Means for solving the problems and effects of the invention] According to the present invention, there is provided a rear image recording device (100) for a vehicle, which includes an imaging unit (rear camera 24) that images the area behind the vehicle, a cut-out control unit (S90) that cuts out a predetermined range (42) of an image (40) captured by the imaging unit, and a recording unit (storage 12) that records the image cut out by the cut-out control unit.

[0009] The vehicle rear image recording device further includes a determination unit (S20) that determines whether or not a following vehicle (62) is present in the captured image (40), and a change unit (S60) that, when it is determined (S40) that the reference position (Pr) of the following vehicle determined by the determination unit is located above a predetermined range (42), changes the upper edge of the predetermined range upward with respect to the captured image so that the reference position falls within the predetermined range.

[0010] According to the above configuration, it is determined whether or not there is a following vehicle in the captured image, and when it is determined that the reference position of the following vehicle is located above the predetermined range, the upper edge of the predetermined range is shifted upward in the captured image so that the reference position falls within the predetermined range.

[0011] Therefore, even if a large following vehicle approaches the vehicle excessively and the driver is displaced upward in the captured image, the upper edge of the specified range is changed upward, thereby increasing the possibility of photographing and recording the driver compared to a case in which the upper edge of the specified range is not changed upward.

[0012] In addition, there is only one imaging unit that captures the rear of the vehicle. Therefore, it is possible to avoid the rear image recording device becoming expensive compared to the case where two imaging units with different angles of view are used. Furthermore, when a following vehicle approaches, the imaging unit is switched to an imaging unit with a different angle of view, and it is possible to avoid the passenger feeling uncomfortable due to the sudden change in the recorded image displayed on the monitor and the sudden change in the sense of distance between the following vehicle and the vehicle.

[0013] [Mode of the invention] In one aspect of the present invention, the modification unit modifies the predetermined range upward with respect to the captured image (S60).

[0014] According to the above aspect, since the predetermined range is changed upward with respect to the captured image, the size of the predetermined range does not change. Therefore, it is possible to avoid an increase in the size of the predetermined range and an increase in the amount of information of the image recorded due to the increase, as occurs when, for example, the upper edge of the predetermined range is changed upward without the lower edge of the predetermined range being changed upward.

[0015] In another aspect of the present invention, the modification unit modifies the upper edge of the specified range upward with respect to the captured image so that the reference position (Pr) falls within the specified range (42), and reduces the lateral width of the specified range so that the entire width of the following vehicle (62) falls within the specified range.

[0016] According to the above aspect, the upper edge of the predetermined range is shifted upward with respect to the captured image so that the reference position falls within the predetermined range, and the width of the predetermined range is reduced so that the entire width of the following vehicle falls within the predetermined range. Therefore, it is possible to avoid an increase in the amount of information of the recorded image due to the change in the predetermined range, or to reduce the increase in the amount of information of the recorded image.

[0017] Furthermore, in another aspect of the present invention, the reference position (Pr) is the position of the upper edge of the windshield (42W) of the following vehicle (42).

[0018] According to the above aspect, the reference position is the position of the upper edge of the windshield of the following vehicle. Therefore, compared to a case where the reference position is the position of the upper edge of the following vehicle, for example, it is possible to prevent the predetermined range from being changed upward unnecessarily early with respect to the range of the image.

[0019] Furthermore, in another aspect of the present invention, the imaging unit (rear camera 14) is configured to capture an image of the rear of the host vehicle (50) to obtain an image to be displayed on the electronic inner mirror (22).

[0020] According to the above aspect, the imaging unit captures an image of the rear of the vehicle to obtain an image to be displayed on the electronic inner mirror. Even if the predetermined range is changed upward with respect to the range of the image, the range of the image displayed by the electronic inner mirror is not changed. Therefore, it is possible to prevent the image displayed by the electronic inner mirror from being unnecessarily changed due to a change in the predetermined range.

[0021] In the above description, in order to facilitate understanding of the present invention, the names and / or symbols used in the embodiments described below are added in parentheses to the configurations of the invention corresponding to those embodiments. However, each component of the present invention is not limited to the components of the embodiments corresponding to the names and / or symbols added in parentheses. Other objects, other features, and associated advantages of the present invention will be easily understood from the description of the embodiments of the present invention described below with reference to the drawings. [Brief description of the drawings]

[0022] [Figure 1] 1 is a diagram showing a rear image recording device for a vehicle according to an embodiment of the present invention; [Diagram 2] 1A and 1B are diagrams illustrating how to cut out an image of a predetermined range from a captured image. [Diagram 3] FIG. 1 is a diagram showing the movement of feature points of stationary objects photographed while a vehicle is traveling. [Figure 4] 11A and 11B are diagrams illustrating movement of feature points of a following vehicle photographed in a situation in which the vehicle is traveling and the following vehicle is approaching. [Diagram 5] 5 is a flowchart corresponding to a recording control program for an image of the rear of the vehicle in the embodiment. [Figure 6] 11A and 11B are diagrams illustrating the operation of the embodiment in a situation where a following vehicle approaches the host vehicle. [Figure 7] 1A and 1B are diagrams illustrating the operation of a conventional rear image recording device in a situation where a following vehicle is excessively close to the host vehicle. [Figure 8] 13A and 13B are diagrams showing the operation of a first modified example in which the upper edge of the predetermined range is changed upward without the lower edge of the predetermined range being changed upward. [Figure 9] 13A and 13B are diagrams showing the operation of a second modified example in which the upper edge of the predetermined area is shifted upward and the lateral width of the predetermined area is reduced. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a vehicle rear image recording device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0024] 1, a vehicle rear image recording device 100 according to an embodiment of the present invention is applied to a vehicle 50, and includes an image recording ECU 10, an inner mirror ECU 20, and a meter ECU 30. ECU stands for an electronic control unit having a microcomputer as a main part.

[0025] The microcomputer of each ECU includes a CPU, ROM, RAM, a readable / writable non-volatile memory (N / M), and an interface (I / F). The CPU realizes various functions by executing instructions (programs, routines) stored in the ROM. Furthermore, these ECUs are connected to each other via a Controller Area Network (CAN) 52 so that they can exchange data (communicate). Therefore, the detection values ​​of sensors (including switches) connected to a specific ECU are also sent to the other ECUs.

[0026] The image recording ECU 10 is connected to a storage 12 that functions as a recording unit for recording an image cut out by a cut-out control unit as described later, and a setting operation unit 14. The storage 12 is a rewritable non-transitory storage medium such as a hard disk drive (HDD) or a solid state drive (SSD).

[0027] The inner mirror CU 20 is connected to an electronic inner mirror 22, a rear camera 24, and a switching device 26. The inner mirror ECU 20 is a control device that controls the operation mode of the electronic inner mirror 22. The electronic inner mirror 22 is installed at the center upper part of the interior side of the windshield glass (not shown), and provides the driver with visual information about the area behind the vehicle 50.

[0028] The switching device 26 has a built-in switch (not shown) for switching the operating mode of the electronic inner mirror 22, and the switching device 26 is configured to switch between the electronic mirror position and the optical mirror position by operating an operating lever not shown in Figure 1.

[0029] When the switching device 216 is set to the electronic mirror position, the electronic inner mirror 22 operates in an electronic mirror mode that displays an image captured by the rear camera 24. On the other hand, when the switching device 26 is set to the optical mirror position, the electronic inner mirror 22 operates in an optical mirror mode that reflects the rear of the vehicle 50 by optical reflection.

[0030] The rear camera 22 is installed at the rear of the vehicle 50, for example, at the upper center of the rear window glass on the interior side of the vehicle, but may be installed in a state exposed to the outside of the vehicle. In the embodiment, the rear camera 22 includes a camera unit that captures an image of the rear of the vehicle 50, and a processing unit that electrically processes information on an image of the rear of the vehicle 50 captured by the camera unit to generate an electric signal. The processing unit supplies an electric signal indicating an image of the rear of the vehicle 50 to the inner mirror ECU 20 at predetermined time intervals. As will be described later, the camera unit also functions as an imaging unit of the rear image recording device 100.

[0031] When the switching device 26 is set to the electronic mirror position, the inner mirror ECU 20 outputs an electric signal to the electronic inner mirror 22, and the electronic inner mirror displays an image of the rear of the vehicle 50 on its display based on the received electric signal. Thus, the occupant can check the situation behind the vehicle 50 by looking at the display of the electronic inner mirror 22.

[0032] 2, the inner mirror ECU 20 cuts out an image of a range (referred to as a "predetermined range") 42 that is narrower in vertical width than the range 40 of the image captured by the rear camera 22. Furthermore, the inner mirror ECU 20 supplies an electrical signal indicating the cut-out image to the image recording ECU 10 via the CAN 52. Thus, the inner mirror ECU 20 also functions as a cut-out control unit that cuts out a predetermined range of the image captured by the rear camera 22.

[0033] In the embodiment, the predetermined range 42 is a range in which the upper and lower parts of the image range 40 have been trimmed, and the width of the predetermined range 42 is the same as the width of the image range 40. As shown by the dashed line in FIG. 2, when the predetermined range 42 is in a preset standard position 42A, the top and bottom widths of the trimmings of the upper and lower parts are the same, but these top and bottom widths may be different from each other. The width of the predetermined range 42 may also be smaller than the width of the image range 40. Furthermore, the relationship of the standard position of the predetermined range 42 to the image range 40 is preset to a constant value, but may be variable by operating the setting operation device 14.

[0034] A display 32 that displays visual information to an occupant of the vehicle 50 is connected to the meter ECU 30. The display 32 may be, for example, a head-up display or a multi-information display that displays meters and various information, or may be a display of a navigation device.

[0035] Although not shown in Fig. 1, the setting operation device 14 includes an image recording switch and a recorded image display switch operated by the occupant, and when the image recording switch is on, an image of the rear of the vehicle 50 is recorded in the storage 12. When the recorded image display switch is on, an image recorded in the storage 12, i.e., an image cut out by the inner mirror ECU 20, is displayed on the monitor of the display 32. When images of areas other than the rear of the vehicle are also recorded, the images of areas other than the rear of the vehicle may be displayed in addition to the cut-out image of the rear of the vehicle. The display 32 may be connected to the image recording ECU 10.

[0036] The inner mirror ECU 20 determines whether or not a following vehicle is present within the range 40 of the captured image. The determination of whether or not a following vehicle is present may be performed in any manner known in the art. Furthermore, when the inner mirror ECU 20 determines that the reference position of the following vehicle is located above the predetermined range 42, the inner mirror ECU 20 changes the predetermined range upward with respect to the range 40 of the captured image, as indicated by reference symbol 42' in FIG. 2, so that the reference position falls within the predetermined range.

[0037] In addition, changing the specified range upward relative to the captured image range 40 may be achieved by reducing the vertical width of the cropping in the upper part of the image range 40 and increasing the vertical width of the cropping in the lower part of the image range 40 by the same amount as the reduced width.

[0038] The reference position of the following vehicle may be the position of the upper edge of the image of the following vehicle, but is preferably, for example, the position of the upper edge of the windshield of the following vehicle so that as much of the image of the driver of the following vehicle as possible falls within the predetermined range. Note that a situation in which the reference position of the following vehicle is located above the predetermined range 42 occurs when the distance between the following vehicle and the host vehicle is excessively reduced, such as when the following vehicle is excessively close to the host vehicle 50.

[0039] As shown in Fig. 3, feature points 60LC and 60RC such as corners of stationary objects 60L and 60R photographed while the vehicle 50 is traveling are displaced so as to approach the vanishing point O within the range 40 of the image. In contrast, feature point 62C of a following vehicle 62 approaching the host vehicle 50 from behind is displaced so as to move away from the vanishing point O within the range 40 of the image, as shown in Fig. 4. When the following vehicle 62 moves away from the host vehicle 50, feature point 62C of the following vehicle is displaced so as to move closer to the vanishing point O within the range 40 of the image.

[0040] Therefore, when the reference position Pr of the following vehicle 62 is located above the predetermined range 42 as shown in Fig. 4, the following vehicle is excessively close to the vehicle 50, such as when the following vehicle is a tailgating vehicle. In this situation, it becomes impossible to capture an image of the driver of the following vehicle, particularly when the following vehicle is a large vehicle such as a truck. Therefore, it is preferable that the license plate and the driver of the following vehicle 62 are captured and recorded as much as possible by changing the predetermined range 42 upward with respect to the range 40 of the captured image as described above.

[0041] <Recording control program for images of the rear of the vehicle> Next, a recording control program for an image of the rear of the vehicle in the embodiment will be described with reference to the flowchart shown in Fig. 5. The image recording control according to the flowchart shown in Fig. 5 is repeatedly executed by the CPU of the inner mirror ECU 20 when the image recording switch of the setting operation unit 14 is on. In the following description, the image recording control is referred to as "main control". The image recording control program may be stored in the ROM of the inner mirror ECU 20.

[0042] First, in step S10, the CPU determines whether or not the shift range of a transmission (not shown in the figure) of the host vehicle 50 is the D range. If the CPU makes a negative determination, it advances this control to step S30, and if the CPU makes a positive determination, it advances this control to step S20.

[0043] In addition, when it becomes necessary to photograph and record the driver of the following vehicle in addition to the license plate of the following vehicle, such as when the following vehicle is a tailgating vehicle, the host vehicle 50 is traveling, and therefore step S10 is performed. Therefore, instead of determining whether the shift range is in the D range, it may be determined whether the vehicle speed of the host vehicle is equal to or greater than a reference value, and the determination of step S10 may be omitted.

[0044] In step S20, the CPU determines whether or not a following vehicle has been photographed, i.e., whether or not there is a following vehicle, by performing image analysis of targets within the image range 40. If the CPU makes a positive determination, i.e., if it determines that there is a following vehicle, it advances this control to step S40, and if the CPU makes a negative determination, it sets the predetermined range 42 to a preset standard position 42A (see FIG. 2) in step S30.

[0045] In step S40, the CPU identifies the reference position of the following vehicle by analyzing the image of the following vehicle. Furthermore, the CPU determines whether or not the reference position of the following vehicle is above a predetermined range 42 within the image range 40. If the CPU makes a negative determination, it advances this control to step S70, and if the CPU makes a positive determination, it advances this control to step S50.

[0046] In step S50, the CPU determines whether the predetermined range 42 is at the top position within the image range 40, that is, whether the upper edge of the predetermined range 42 coincides with the upper edge of the image range 40 and the predetermined range 42 cannot be further changed upward. If the CPU makes a positive determination, it proceeds to step S90, and if the CPU makes a negative determination, it proceeds to step S60.

[0047] In step S60, the CPU changes the predetermined range 42 upward within the image range 40, for example as shown by the symbol 42' in FIG. 2, so that the reference position of the following vehicle is located within the changed predetermined range 42.

[0048] In step S70, the CPU determines whether or not the predetermined range 42 is in the standard position 42A. If the CPU makes an affirmative determination, the control proceeds to step S90, and if the CPU makes a negative determination, that is, if the CPU determines that the predetermined range 42 has been changed upward from the standard position 42A, the control proceeds to step S80.

[0049] In step S80, the CPU changes the predetermined range 42 downward within the image range 40 so that the reference position of the following vehicle remains within the changed predetermined range 42 and the reference position is not above the changed predetermined range. In other words, the CPU moves the position of the predetermined range 42 closer to the standard position 42A.

[0050] In step S90, the CPU cuts out an image of a predetermined range 42 from the image captured by the rear camera 22 (image of the image range 40), and supplies an electrical signal indicating the cut-out image to the image recording ECU 10 via the CAN 52. The image recording ECU 10 records in the storage 12 image information corresponding to the received electrical signal.

[0051] In step S100, the CPU judges whether or not the image recording end condition is satisfied. If the CPU judges negative, it temporarily ends this control, and if the CPU judges positive, it outputs a command to end image recording to the image recording ECU 10 in step S110. When the image recording ECU 10 receives the command to end image recording, it ends image recording.

[0052] In addition, it may be determined that the condition for terminating image recording is met, for example, when the image recording switch of the setting operation device 14 is off, or when a collision sensor of the vehicle (not shown) detects that a following vehicle has collided with the vehicle 50.

[0053] As can be seen from the above description, the inner mirror ECU 20 executes step S20 to function as a determination unit that determines whether or not a following vehicle is present in the captured image. Also, by executing steps S40 and S60, the inner mirror ECU 20 executes steps S40 and S60 to function as a change unit that changes the upper edge of the predetermined range upward in the captured image so that the reference position falls within the predetermined range when the determination unit determines that the reference position of the following vehicle is located at the upper side of the predetermined range. Furthermore, by executing step S90, the inner mirror ECU 20 executes step S90 to function as a cut-out control unit that cuts out a predetermined range of the image captured by the imaging unit.

[0054] <Example of operation of the embodiment> Figures 6 (A) to (C) show a situation in which a following vehicle 62 (not shown in Figure 6) approaches the host vehicle while the host vehicle is traveling, and in (A) and (B), the predetermined range 42 is set to its standard position 42A.

[0055] In (A), substantially the entirety of the following vehicle 62 is within the predetermined range 42. In (B), the upper edge of the following vehicle 62 is above the predetermined range 42, but the reference position Pr, which is the upper edge of the windshield 62W of the following vehicle 62, is within the predetermined range 42.

[0056] In (C), the following vehicle 62 is excessively close to the vehicle itself, and the reference position Pr of the following vehicle 62 is above the predetermined range 42 when the following vehicle 62 is in the standard position 42A. Therefore, the predetermined range 42 is changed upward with respect to the image range 40 so that the reference position Pr is within the changed predetermined range 42'.

[0057] In the case of a conventional rear image recording device in which the predetermined range 42 is not changed upward with respect to the image range 40, as shown in Fig. 7, in the above situation (C), the main part of the windshield 62W does not fit within the predetermined range 42. Therefore, image information of the driver 62D of the following vehicle 62 cannot be recorded.

[0058] In contrast, in the case of the embodiment, in the above situation (C), the predetermined range 42 is changed upward with respect to the image range 40 so that the reference position Pr is within the changed predetermined range 42'. Therefore, since the entire windshield 62W falls within the changed predetermined range 42', it is possible to increase the possibility of recording image information such as a face for identifying the driver 62D of the following vehicle 62. In other words, it is possible to increase the possibility of recording image information including both the driver 62D and the license plate 62N of the following vehicle.

[0059] <First modified example> In the embodiment, the predetermined range 42 is changed upward with respect to the image range 40. That is, the amount by which the lower edge of the predetermined range 42 is changed upward is the same as the amount by which the upper edge of the predetermined range 42 is changed upward. In contrast, in the first modified example, as shown in Fig. 8, the lower edge of the predetermined range 42 is not changed upward, and the upper edge of the predetermined range 42 is changed upward. Note that this process may be executed in place of step S60 in the embodiment.

[0060] According to the embodiment, even if the predetermined range 42 is shifted upward with respect to the image range 40, the size of the predetermined range does not change. Therefore, the amount of image information supplied to the image recording ECU 10 via the inner mirror ECU 20CAN52 does not increase.

[0061] In contrast, according to the first modified example, the size of the predetermined range increases with the upward shift of the upper edge, and therefore the amount of image information supplied to the image recording ECU 10 via the inner mirror ECU 20CAN52 increases. However, since the lower edge of the predetermined range 42 is not shifted upward, the time required to record image information including both the driver and license plate of the following vehicle can be made longer than in the embodiment.

[0062] <Second modified example> 9, in the second modified example, the upper edge of the predetermined range 42 is moved upward with respect to the image range 40 without moving the lower edge of the predetermined range 42 upward so that the reference position Pr falls within the predetermined range. Furthermore, the lateral width of the predetermined range is reduced so that the entire width of the following vehicle 62 falls within the predetermined range. This process may also be executed in place of step S60 in the embodiment.

[0063] According to the second variant, it is possible to suppress or avoid an increase in the amount of image information supplied to the image recording ECU 10 via the inner mirror ECU 20CAN52, while lengthening the time required to record image information including both the driver and license plate of the following vehicle compared to the embodiment.

[0064] In the first and second modified examples described above, the lower edge of the specified range 42 is not changed upward, but the lower edge of the specified range 42 may also be changed upward by a length that is shorter than the length by which the upper edge of the specified range is changed upward.

[0065] As can be seen from the above description, according to the embodiment and the first and second modified examples, the imaging unit that images the rear of the vehicle 50 is one rear camera 24. Therefore, it is possible to avoid the rear image recording device becoming expensive compared to the case where two cameras with different angles of view are used. In addition, when a following vehicle approaches, the camera that captures the image is switched, and it is possible to avoid the occupants feeling uncomfortable due to the sudden change in the recorded image displayed on the monitor of the display 32 and the sudden change in the sense of distance of the following vehicle from the vehicle.

[0066] According to the embodiment and the first and second modified examples, the reference position Pr of the following vehicle is the position of the upper edge of the windshield of the following vehicle. Therefore, compared to the case where the reference position of the following vehicle is, for example, the position of the upper edge of the following vehicle, it is possible to prevent the predetermined range 42 from being unnecessarily quickly changed upward with respect to the range 40 of the image.

[0067] According to the embodiment and the first and second modified examples, the imaging unit is a rear camera 24 configured to capture an image of the rear of the vehicle 50 in order to obtain an image to be displayed on the electronic inner mirror 22. Even if the predetermined range 42 is changed upward with respect to the image range 40, the range of the image displayed by the electronic inner mirror 22 is not changed. Therefore, the image displayed by the electronic inner mirror 22 does not change due to the change in the predetermined range 42.

[0068] Furthermore, according to the embodiment and the first and second modified examples, the function of the cut-out control unit that cuts out a predetermined range of the image captured by the imaging unit is achieved by the inner mirror ECU 20 (step S90). Therefore, compared to the case where the function of the cut-out control unit is achieved by the image recording ECU 10, the amount of image information transmitted from the inner mirror ECU 20 to the image recording ECU 10 via the CAN 52 can be reduced.

[0069] Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to the above-described embodiments, and it will be apparent to those skilled in the art that various other embodiments are possible within the scope of the present invention.

[0070] For example, in the above-described embodiment and the first and second modified examples, the functions of the determination unit that determines whether or not there is a following vehicle, the change unit that changes the upper edge of the predetermined range upward, and the cut-out control unit that cuts out the predetermined range of the image are performed by the inner mirror ECU 20. However, at least one of the functions of the determination unit, the change unit, and the cut-out control unit may be performed by the imaging unit, i.e., the rear camera, or may be performed by the image recording ECU 10. Furthermore, the image recording ECU 10 and the inner mirror ECU 20 may be integrated, and the functions of the determination unit, the change unit, and the cut-out control unit may be performed by the integrated ECU.

[0071] Furthermore, if the following vehicle is a small vehicle, even if the following vehicle approaches the vehicle excessively close, the reference position such as the upper edge of the windshield will not be on the upper side of the predetermined range. In contrast, the reference position such as the corner of the license plate is likely to be on the lower side of the predetermined range. Therefore, when it is determined that the reference position such as the corner of the license plate is on the lower side of the predetermined range, the lower edge of the predetermined range may be changed downward in the captured image so that the reference position falls within the predetermined range.

[0072] Furthermore, in the above-described embodiment and the first and second modified examples, the imaging unit is the rear camera 24 configured to capture an image of the rear of the vehicle 50 in order to obtain an image to be displayed on the electronic inner mirror 22. However, the imaging unit may be a driving assistance camera other than the camera that captures an image to be displayed on the electronic inner mirror 22. [Explanation of symbols]

[0073] 10: image recording ECU, 12: storage, 14: setting operation device, 20: inner mirror ECU, 22: electronic inner mirror, 24: rear camera, 32: display, 40: image range, 42: predetermined range, 50: host vehicle, 62: following vehicle

Claims

1. A rear image recording device for a vehicle includes an imaging unit that images a rear area of ​​a vehicle, a cutout control unit that cuts out a predetermined range of an image captured by the imaging unit, and a recording unit that records the image cut out by the cutout control unit, The rear image recording device for a vehicle further includes a determination unit that determines whether or not a following vehicle is present in the captured image, and a change unit that, when it is determined that the reference position of the following vehicle determined by the determination unit is located above the predetermined range, changes the upper edge of the predetermined range upward with respect to the captured image so that the reference position falls within the predetermined range.

2. 2. The rear image recording device for a vehicle according to claim 1, wherein the change unit changes the predetermined range upward with respect to the captured image.

3. 2. The rear image recording device for a vehicle according to claim 1, wherein the change unit changes an upper edge of the predetermined range upward with respect to the captured image so that the reference position falls within the predetermined range, and reduces a lateral width of the predetermined range so that the following vehicle falls within the predetermined range over its entire width.

4. 2. The rear image recording device for a vehicle according to claim 1, wherein the reference position is a position of an upper edge of a windshield of the following vehicle.

5. 2. The rear image recording device for a vehicle according to claim 1, wherein the imaging unit is configured to capture an image of the rear of the vehicle in order to obtain an image to be displayed on an electronic inner mirror.

Images