Imaging device, control method, program and storage medium

Abstract

To provide a shooting device which allows for acquisition of an image reflecting an appropriate range, without adjusting the camera angle, even when the shooting direction is changed.SOLUTION: A drive recorder 1 includes a front photographing camera 4 for photographing the front scenery of a vehicle, and a control unit 19. The control unit 19 cuts out a partial range of the front image Im photographed by the front photographing camera 4, as a cut-out image Imc. The control unit 19 determines the presence or absence of possibility that the photographing direction of the front photographing camera 4 has changed. When a determination is made that the photographing direction of the front photographing camera 4 has possibly changed, the control unit 19 determines the cut-out position of the cut-out image Imc, so that the position of a characteristic object in the cut-out image Imc, after affirmative determination, substantially matches the position in the cut-out image Imc before the affirmative determination.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a technique for cutting out and displaying a forward image captured from a vehicle. [Background technology]

[0002] Conventionally, there have been known drive recorders that can be attached to rearview mirrors, etc. For example, Patent Document 1 discloses a drive recorder that can be attached to a rearview mirror and that includes a half mirror, a liquid crystal display, and a camera unit that captures an image in front of the vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-229049 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, if the angle of the rearview mirror is changed due to a change in driver or other reasons, the camera's shooting direction also changes, so when the angle of the rearview mirror is adjusted, the camera angle also needs to be adjusted.

[0005] The present invention has been made to solve the above-mentioned problems, and its main object is to provide a photographing device that can acquire an image that captures an appropriate range without adjusting the camera angle, even when the shooting direction is changed. [Means for solving the problem]

[0006] The claimed invention is A photographing device mounted on a vehicle, an imaging means for imaging a scene ahead of the vehicle; an image control means for cutting out a partial range of a photographed image, which is an image photographed by the photographing means, as a cut-out image; a determination means for determining whether or not there is a possibility of changing the photographing direction of the photographing means based on information about the driver's seat of the vehicle; Equipped with The image control means is characterized in that, when the judgment means judges that there is a possibility of change, it adjusts the image cropping range after the judgment so that the position of the first object in the cropped image before the judgment approximately coincides with the position of the first object in the cropped image after the judgment. The claimed invention also includes: A photographing device mounted on a vehicle, an imaging means for imaging a scene ahead of the vehicle; an image control means for cutting out a partial range of a photographed image, which is an image photographed by the photographing means, as a cut-out image; a determining means for determining whether or not there is a possibility of changing the photographing direction of the photographing means based on information about the operating state of the photographing device; Equipped with the determination means determines that there is a possibility of change when information indicating that the photographing device has changed from an operating state to a non-operating state and then changed back to an operating state is acquired; The image control means is characterized in that, when the judgment means judges that there is a possibility of change, it adjusts the image cropping range after the judgment so that the position of the first object in the cropped image before the judgment approximately coincides with the position of the first object in the cropped image after the judgment.

[0007] The claimed invention also includes: A control method executed by an imaging device that is mounted on a vehicle and has imaging means that captures an image ahead of the vehicle, comprising: an image control step of cutting out a partial range of the image captured by the image capturing means as a cut-out image; a determination step of determining whether or not there is a possibility of a change in the photographing direction of the photographing means based on information about the driver's seat of the vehicle; and The image control process is characterized in that, when the judgment process determines that there is a possibility of change, the image cropping range after the judgment is adjusted so that the position of the first object in the cropped image before the judgment approximately coincides with the position of the first object in the cropped image after the judgment. The claimed invention also includes: A control method executed by an imaging device that is mounted on a vehicle and has imaging means that captures an image ahead of the vehicle, comprising: an image control step of cutting out a partial range of the image captured by the image capturing means as a cut-out image; a determining step of determining whether or not there is a possibility of changing the photographing direction of the photographing means based on information about the operating state of the photographing device; and the determining step determines that there is a possibility of change when information indicating that the photographing device has changed from an operating state to a non-operating state and then changed back to an operating state is acquired; The image control process is characterized in that, when the judgment process determines that there is a possibility of change, the image cropping range after the judgment is adjusted so that the position of the first object in the cropped image before the judgment approximately coincides with the position of the first object in the cropped image after the judgment.

[0008] The claimed invention also includes: A program executed by a computer of an imaging device that is mounted on a vehicle and has imaging means for imaging a scene ahead of the vehicle, The computer an image control means for cutting out a partial range of the image captured by the image capturing means as a cut-out image; and functioning as a determination means for determining whether or not there is a possibility of a change in the photographing direction of the photographing means based on information about the driver's seat of the vehicle; The image control means is characterized in that, when the judgment means judges that there is a possibility of change, it adjusts the image cropping range after the judgment so that the position of the first object in the cropped image before the judgment approximately coincides with the position of the first object in the cropped image after the judgment. The claimed invention also includes: A program executed by a computer of an imaging device that is mounted on a vehicle and has imaging means for imaging a scene ahead of the vehicle, The computer an image control means for cutting out a partial range of the image captured by the image capturing means as a cut-out image; and functioning as a determination means for determining whether or not there is a possibility of changing the photographing direction of the photographing means based on information about the operating state of the photographing device; the determination means determines that there is a possibility of change when information indicating that the photographing device has changed from an operating state to a non-operating state and then changed back to an operating state is acquired; The image control means is characterized in that, when the judgment means judges that there is a possibility of change, it adjusts the image cropping range after the judgment so that the position of the first object in the cropped image before the judgment approximately coincides with the position of the first object in the cropped image after the judgment. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 2 is a front view of the drive recorder. [Figure 2] 2A and 2B are a rear view and a top view of the drive recorder. [Figure 3] FIG. 1 is a block diagram of a drive recorder. [Figure 4] 10 is a flowchart showing an outline of a process for adjusting the cutout position of a front image. [Figure 5] 10 is a flowchart showing the procedure of a cutout position adjustment process. [Figure 6] A specific example of a method for adjusting the cut-out position of the front image will be described. [Figure 7] 10 is a flowchart showing a process for adjusting the cut-out position of a front image according to a modified example. [Figure 8] FIG. 10 is a front view of a drive recorder according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0010] In one preferred embodiment of the present invention, an imaging device is mounted on a vehicle and captures a scene ahead, comprising: an imaging means for capturing the scene ahead; an image control means for cutting out a partial range of an image captured by the imaging means as a cropped image; and a determination means for determining whether or not there is a possibility that the imaging direction of the imaging means has changed. When the determination means determines that there is a possibility that the imaging direction of the imaging means has changed, the image control means crops out the cropped image after it has been determined that there is a possibility that the imaging direction of the imaging means has changed so that the position of the object in the cropped image after it has been determined that there is a possibility is approximately the same as the position in the cropped image before it was determined that there is a possibility.

[0011] The photographing device includes a photographing means for photographing a scene ahead of the vehicle, an image control means, and a determination means. The image control means cuts out a partial range of an image photographed by the photographing means as a cropped image. The determination means determines whether or not the photographing direction of the photographing means may have changed. When the determination means determines that the photographing direction of the photographing means may have changed, the image control means crops out the cropped image after it has been determined that the photographing direction may have changed so that the position of the object in the cropped image after it has been determined that the photographing direction may have changed substantially matches the position in the cropped image before it was determined that the photographing direction may have changed. In this way, the photographing device can obtain an image with the same display range as before the photographing direction of the photographing means changed, without adjusting the angle of the photographing means. Furthermore, the photographing device can suitably reduce processing load during normal operation by changing the crop position only when there is a possibility that the photographing direction of the photographing means has changed.

[0012] In one aspect of the above-described photographing device, when the determination means determines that the photographing direction of the photographing means may have changed and the vehicle is stopped, the image control means cuts out the image after it has been determined that there is a possibility that the photographing direction of the photographing means has changed so that the position of the object in the cutout image after it has been determined that there is a possibility substantially matches the position of the object in the cutout image before it was determined that there is a possibility. With this aspect, the photographing device can suitably grasp the correspondence between the images of the photographing means before and after the photographing direction of the photographing means changes, and adjust the cutout position.

[0013] In another aspect of the above-described photographing device, when a contact sensor that detects contact with the photographing device detects contact with the photographing device, the photographing device determines that the photographing direction of the photographing means may have changed. This aspect allows the photographing device to preferably determine whether the photographing direction of the photographing means may have changed.

[0014] In another aspect of the above-mentioned photographing device, the photographing device further includes a switching means for switching the state of the photographing device between an operating state and a non-operating state, and the determination means determines that the photographing direction of the photographing means may have changed when the switching means switches the state of the photographing device from the operating state to the non-operating state and then back to the operating state. This aspect also allows the photographing device to preferably determine whether the photographing direction of the photographing means may have changed.

[0015] In another aspect of the above-mentioned photographing device, the photographing device includes a second photographing means for photographing a driver's seat of the vehicle, and the determination means determines that the photographing direction of the photographing means may have changed when it determines that the driver has changed or there is a possibility that the driver has changed based on the image photographed by the second photographing means. Even in this aspect, the photographing device can adjust the crop position of the image only when the photographing direction of the photographing means has changed or there is a possibility that the direction has changed.

[0016] In another aspect of the above-mentioned photographing device, the determination means includes an acquisition means for acquiring information on whether the driver of the vehicle is seated in the driver's seat or whether the seat belt is fastened, and when the determination means determines that the driver may have changed based on the information acquired by the acquisition means, the determination means determines that the photographing direction of the photographing means may have changed. This aspect also allows the photographing device to preferably determine whether the photographing direction of the photographing means may have changed.

[0017] In another aspect of the above-described photographing device, the photographing device is built into or attached to the rearview mirror of the vehicle. In this case, the photographing direction of the photographing means is changed by adjusting the angle of the rearview mirror. Even in this case, the photographing device can adjust the crop position and obtain an image that captures an appropriate range as the cropped image.

[0018] In another embodiment of the present invention, a control method is executed by a photographing device mounted on a vehicle and having a photographing means for photographing a forward scene, the control method including an image control step of cropping a portion of an image captured by the photographing means as a cropped image, and a determination step of determining whether or not the photographing direction of the photographing means may have changed. When the determination step determines that the photographing direction of the photographing means may have changed, the image control step crops the cropped image after the determination that the photographing direction of the photographing means may have changed so that the position of the object in the cropped image after the determination that the photographing direction may have changed substantially matches the position in the cropped image before the determination that the photographing direction may have changed. By executing this control method, the photographing device can obtain an image with the same display range as before the photographing direction of the photographing means was changed, without adjusting the angle of the photographing means. Furthermore, the photographing device can suitably reduce the processing load during normal operation by changing the crop position only when there is a possibility that the photographing direction of the photographing means has changed.

[0019] In another embodiment of the present invention, a program executed by a computer electrically connected to a vehicle-mounted imaging device for capturing a forward scene causes the computer to function as an image control device that crops out a portion of an image captured by the imaging device as a cropped image, and as a determination device that determines whether or not the imaging direction of the imaging device may have changed. When the determination device determines that the imaging direction of the imaging device may have changed, the image control device crops out the cropped image after the determination that the imaging direction of the imaging device may have changed so that the position of the object in the cropped image after the determination that the imaging direction of the imaging device may have changed substantially matches the position in the cropped image before the determination that the imaging direction of the imaging device may have changed. By executing this program, the computer can obtain an image with the same display range as before the imaging direction of the imaging device changed, without adjusting the angle of the imaging device. Furthermore, by changing the crop position only when there is a possibility that the imaging direction of the imaging device has changed, the processing load during normal operation can be suitably reduced. Preferably, the program is stored in a storage medium. [Example]

[0020] Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings. Hereinafter, the term "shooting direction" refers to the direction in front of the camera, passing through the center of the field of view (shooting range) of the camera.

[0021] [Drive recorder configuration] 1 and 2 show the configuration of a drive recorder 1 according to an embodiment. Specifically, FIG. 1 shows a front view of the drive recorder 1 attached to a rearview mirror 12 inside a vehicle (also simply referred to as the "attached state"). FIG. 2(A) shows a rear view of the drive recorder 1 in the attached state, and FIG. 2(B) shows a top view of the drive recorder 1 in the attached state. Hereinafter, the longitudinal direction of the drive recorder 1 will be referred to as the "Y-axis direction," the lateral direction of the drive recorder 1 as the "X-axis direction," and the direction perpendicular to the Y-axis and X-axis as the "Z-axis direction," and the positive directions will be defined as shown in the figures.

[0022] The drive recorder 1 is powered by a built-in secondary battery and mainly comprises a mirror unit 13, a forward-viewing camera 4, a display (display means) 10 on the back of the mirror unit 13, and clamping units 14A to 14D. When the drive recorder 1 is attached, the clamping units 14A to 14D clamp the rearview mirror 12, thereby fixing the drive recorder 1 to the rearview mirror 12. When the drive recorder 1 is attached, the mirror surface of the rearview mirror 12 overlaps with the back of the drive recorder 1. The drive recorder 1 is an example of the "imaging device" in the present invention.

[0023] The front photographing camera 4 is a camera for generating an image of the area in front of the vehicle (also referred to as a "front image Im"), and is arranged on the rear surface of the drive recorder 1 so as not to overlap with the rearview mirror 12 when the drive recorder 1 is mounted. The front photographing camera 4 is a wide-angle camera with a wide angle of view in the horizontal direction. The front photographing camera 4 is rotatably housed within the housing of the navigation device 1, and the photographing direction can be adjusted based on the operation of a remote controller or the like (not shown). The front photographing camera 4 is an example of the "photographing means" in the present invention.

[0024] The mirror unit 13 is, for example, a half mirror that transmits a portion of incident light and reflects the rest of the light. As a result, the mirror unit 13 functions as a normal mirror that reflects the scenery behind the vehicle when the display 10 on the back is in a non-emitting state, and when the display 10 is in an emitting state, the mirror unit 13 transmits the light emitted from the display 10, allowing the driver to view the display content of the display 10.

[0025] The display 10 displays an image (also referred to as a "cut-out image Imc") cut out from the forward image Im. As will be described later, the cut-out image Imc is an image cut out from the forward image Im so that the forward scenery in front of the vehicle is at the center of the image, and has fewer vertical and horizontal pixels than the forward image Im. The display 10 also displays an image (also referred to as a "guidance image") showing characters, figures, etc. to guide the driver superimposed on the cut-out image Imc. In FIG. 1, the display 10 displays a guide image showing the vehicle speed and a guide image in a square frame highlighting a lit signal light superimposed on the cut-out image Imc.

[0026] 3 is a functional block diagram of the drive recorder 1. As shown in FIG. 3, the drive recorder 1 includes a vehicle information acquisition unit 3, a front-view camera 4, a contact sensor 5, an acceleration sensor 6, an operation unit 9, a display 10, a RAM 11, a non-volatile memory 15, and a control unit 19.

[0027] The vehicle information acquisition unit 3 is connected to the vehicle's ECU (Electronic Control Unit) via wired or wireless communication and acquires the vehicle's traveling speed, seating information regarding whether the driver is seated or not based on the output from a weight sensor (not shown) provided in the driver's seat, and wearing information regarding whether the driver's seat belt is fastened or not, etc. The vehicle information acquisition unit 3 is an example of the "acquisition means" in the present invention.

[0028] When the contact sensor 5 detects contact with the drive recorder 1, it supplies a detection signal to the control unit 19. The contact sensor 5 may be a touch panel provided on the mirror surface of the rearview mirror 12, or may be a pressure-sensitive switch provided on the housing of the drive recorder 1 or the like that the passenger touches when changing the angle of the rearview mirror 12.

[0029] The operation unit 9 is an interface for accepting various operations on the drive recorder 1, and includes, for example, operation buttons, a touch panel provided on the mirror unit 13 that overlaps with the rearview mirror 12, a remote controller, and a power switch for turning the power of the drive recorder 1 on and off.

[0030] The RAM 11 is a storage area that functions as an image buffer or the like for temporarily storing a cut-out image Imc cut out by the control unit 19 from the forward image Im.

[0031] The nonvolatile memory 15 is a storage medium such as an SD card, and when an impact occurs due to an accident or the like, the control unit 19 writes images for a predetermined time before the impact that are stored in the RAM 11. Furthermore, when the control unit 19 determines that the angle of the rearview mirror 12 may have been changed while the vehicle was stopped, the control unit 19 writes to the nonvolatile memory 15 a front image Im that was generated immediately before the determination and stored in the RAM 11.

[0032] The control unit 19 is a CPU or the like, and generates a cropped image Imc by cropping a portion from the forward image Im, and displays the cropped image Imc on the display 10. The control unit 19 also writes the cropped image Imc displayed on the display 10 to the RAM 11, thereby storing a predetermined amount of cropped images Imc in the RAM 11. Here, in the initial state, the control unit 19 sets the crop position within the forward image Im so that the center of the cropped image Imc coincides with the center of the forward image Im. Note that in the initial state, the shooting direction of the forward shooting camera 4 is adjusted based on a user's operation or the like so that it faces the front (traveling) direction of the vehicle.

[0033] Furthermore, when the acceleration sensor 6 detects an acceleration (i.e., an impact) equal to or greater than a reference value, the control unit 19 writes the cut-out image Imc for a predetermined time period (approximately 10 to 100 seconds) stored in the RAM 11 to the non-volatile memory 15. Furthermore, in this embodiment, the control unit 19 determines whether or not the angle of the rearview mirror 12 may have changed while the vehicle was stopped, based on the output of the contact sensor 5 and the vehicle's traveling speed acquired by the vehicle information acquisition unit 3. Then, when the angle of the rearview mirror 12 may have changed while the vehicle was stopped, the control unit 19 adjusts the position at which the cut-out image Imc is cut out from the forward image Im. The control unit 19 is an example of the "determination means," "image control means," and "computer" that executes a program in the present invention.

[0034] [Adjust crop position] Next, a method for adjusting the cut-out position of the cut-out image Imc will be specifically described.

[0035] (1) Adjustment Timing 4 is a flowchart showing the execution timing of the process of adjusting the cut-out position of the cut-out image Imc. In summary, the control unit 19 adjusts the cut-out position of the cut-out image Imc when the vehicle is stopped and contact with the drive recorder 1 is detected. The control unit 19 repeatedly executes the process of the flowchart shown in FIG.

[0036] First, the control unit 19 determines whether the vehicle equipped with the drive recorder 1 is stopped (step S101). In this case, the control unit 19 determines whether the vehicle is stopped based on the vehicle travel information acquired by the vehicle information acquisition unit 3. Then, if the vehicle is not stopped (step S101; No), the control unit 19 continues to monitor whether the vehicle is stopped. If the vehicle is moving, the scenery ahead of the vehicle displayed in the front image Im changes, and therefore the adjustment of the cut-out position of the cut-out image Imc cannot be performed appropriately. Therefore, the control unit 19 adjusts the cut-out position of the cut-out image Imc only when the vehicle is stopped.

[0037] When the control unit 19 determines that the vehicle is stopped (step S101; Yes), it determines whether or not there has been contact with the drive recorder 1 based on the output of the contact sensor 5 (step S102). As a result, the control unit 19 determines whether or not there is a possibility that the shooting direction of the front photographing camera 4 has changed. Then, when the control unit 19 cannot detect contact with the drive recorder 1 by the contact sensor 5 (step S102; No), it determines that there is no possibility that the shooting direction of the front photographing camera 4 has changed, and returns the process to step S101 again.

[0038] On the other hand, when the control unit 19 determines that there has been contact with the drive recorder 1 based on the output of the contact sensor 5 (step S102; Yes), it determines that there is a possibility that the shooting direction of the front-mounted imaging camera 4 has changed. Therefore, in this case, the control unit 19 stores in the non-volatile memory 15 the clipped image Imc taken immediately before the contact was detected (step S103). Specifically, the control unit 19 writes the most recent image of the clipped images Imc stored in the RAM 11 for a predetermined time period at the time of the contact detection into the non-volatile memory 15. Then, the control unit 19 continues to monitor the output of the contact sensor 5 and determines whether the contact with the drive recorder 1 has ended (step S104).

[0039] Then, when the control unit 19 determines that the contact with the drive recorder 1 has ended based on the output of the contact sensor 5 (step S104; Yes), it determines that the angle adjustment of the rearview mirror 12 has been completed and the user's hand has been removed from the drive recorder 1. Therefore, in this case, the control unit 19 executes a cut-out position adjustment process (step S105) which will be described later with reference to Fig. 5. On the other hand, when the contact sensor 5 continues to detect contact with the drive recorder 1 (step S104; No), the control unit 19 continues to monitor the timing when the contact with the drive recorder 1 will end in step S104.

[0040] (2) Cutout position adjustment processing Fig. 5 is a flowchart showing the procedure of the cutout position adjustment process to be executed in step S105 of Fig. 4. In summary, the control unit 19 determines the cutout position of the cutout image Imc based on the positions of features that appear in common in the cutout image Imc stored in the nonvolatile memory 15 in step S103 of Fig. 4 and the forward image Im currently being captured.

[0041] First, the control unit 19 detects feature objects displayed in the clipped image Imc before contact with the drive recorder 1, which was stored in the non-volatile memory 15 in step S103 of FIG. 4, based on a known image recognition process or the like (step S201). Here, a "feature object" refers to a landmark object, such as a white line on a road, a signboard, a traffic sign, a building, a tree, or other feature. In this case, the control unit 19 preferably performs feature object detection on a binarized image obtained by binarizing the clipped image Imc of the target. Alternatively, the control unit 19 may store feature information of objects that are candidates for feature objects in advance and detect feature objects by referring to the feature information.

[0042] Next, the control unit 19 detects features from the front image Im immediately acquired from the front photographing camera 4, that is, from the front image Im generated after contact is no longer detected in step S104 (step S202). In this case, the control unit 19 preferably performs feature detection on a binarized image obtained by binarizing the target front image Im.

[0043] Then, the control unit 19 determines whether or not a feature identical to the feature detected in step S201 (also referred to as a "common feature") has been detected in step S202 (step S203). For example, in this case, the control unit 19 calculates feature amounts representing color information and shape information of each feature detected in steps S201 and S202, and compares the feature amounts to determine whether or not a common feature exists. In this case, the control unit 19 may score the degree of match between the features, and may consider a pair of features with a score equal to or greater than a predetermined value to be a common feature.

[0044] Then, when the control unit 19 determines that a common feature exists (step S203; Yes), it changes the cut-out position of the cut-out image Imc based on the position of the common feature in the cut-out image Imc before contact detection (step S204). Specifically, the control unit 19 changes the cut-out position so that the position of the common feature in the cut-out image Imc before contact detection matches the position of the common feature in the cut-out image Imc based on the new cut-out position. In this case, the control unit 19 may calculate the amount of movement of the common feature on the front image Im before and after contact detection, and move the cut-out position of the cut-out image Imc by the calculated amount of movement.

[0045] On the other hand, if the control unit 19 determines that no common feature exists (step S203; No), the control unit 19 ends the processing of the flowchart. That is, in this case, the control unit 19 determines that it is not possible to grasp the correspondence between the cropped image Imc stored in the nonvolatile memory 15 and the current forward image Im, and ends the processing of the flowchart.

[0046] (3) Specific examples Next, a specific example of a method for adjusting the cut-out position of the cut-out image Imc based on FIGS. 4 and 5 will be described with reference to FIG.

[0047] Fig. 6(A) shows the front image Im and the cut-out position of the cut-out image Imc generated immediately before adjusting the angle of the rearview mirror 12. In the example of Fig. 6(A), the shooting direction of the front shooting camera 4 faces the traveling direction of the vehicle, and the center of the front image Im and the center of the cut-out image Imc coincide with each other.

[0048] 6(B) shows a front image Im after the driver adjusts the angle of the rearview mirror 12 while the vehicle is stopped. In the example of FIG. 6(B), the driver changes the angle of the rearview mirror 12, causing the shooting direction of the front shooting camera 4 to move upward and to the right. In this case, the control unit 19 detects contact with the drive recorder 1 using the contact sensor 5 (see step S102 in FIG. 4), and writes the cropped image Imc, which was captured immediately before the angle of the rearview mirror 12 was changed and stored in the RAM 11, to the non-volatile memory 15 (see step S103).

[0049] Fig. 6(C) shows the cut-out position of the cut-out image Imc set in the case of Fig. 6(B). When the contact sensor 5 no longer detects contact with the drive recorder 1 (see step S104), the control unit 19 reads out the cut-out image Imc (see Fig. 6(A)) written to the non-volatile memory 15. Then, the control unit 19 detects features in each of the read-out cut-out image Imc and the front image Im (see Fig. 6(B)) immediately acquired from the front imaging camera 4 (see steps S201 and S202 in Fig. 5). Here, the control unit 19 detects a traffic light as a common feature (see step S203).

[0050] Then, based on the position of the traffic light, which is the common feature, the control unit 19 recognizes the range in the forward image Im in FIG. 6(B) that corresponds to the cropped image Imc in FIG. 6(A) and determines this range as the crop position of the cropped image Imc (see step S204). In this case, the cropped image Imc shown in FIG. 6(A) and the cropped image Imc shown in FIG. 6(C) have substantially the same display range. As a result, the display range of the cropped image Imc shown in FIG. 6(C) is centered on the front direction of the vehicle, even after the angle of the rearview mirror 12 is changed. In this way, the control unit 19 can suitably acquire the cropped image Imc that shows the front direction of the vehicle.

[0051] As described above, the drive recorder 1 according to this embodiment includes the front-facing camera 4 that captures the scenery ahead of the vehicle and the control unit 19. The control unit 19 cuts out a partial range of the front image Im captured by the front-facing camera 4 as a cutout image Imc. The control unit 19 determines whether the shooting direction of the front-facing camera 4 may have changed. When the control unit 19 determines that the shooting direction of the front-facing camera 4 may have changed, the control unit 19 determines the cutout position of the cutout image Imc so that the positions of the features in the cutout image Imc after it has been determined that the shooting direction may have changed substantially coincide with the positions of the features in the cutout image Imc before it was determined that the shooting direction may have changed. In this way, the drive recorder 1 can display and store the cutout image Imc having the same shooting range as before the shooting direction of the front-facing camera 4 was changed, without adjusting the angle of the front-facing camera 4. Furthermore, the drive recorder 1 can suitably reduce the processing load during normal operation by changing the cutout position only when there is a possibility that the shooting direction of the front-facing camera 4 has changed.

[0052] [Variations] Preferred modifications of the above-described embodiment will be described below. The following modifications may be applied to the above-described embodiment in any combination.

[0053] (Variation 1) The control unit 19 adjusted the cut-out position of the cut-out image Imc when the contact sensor 5 detected contact with the drive recorder 1. However, the application of the present invention is not limited to this.

[0054] For example, in addition to or instead of determining whether or not the cut-out position needs to be adjusted based on the output of the contact sensor 5, the control unit 19 may determine whether or not the cut-out position needs to be adjusted based on the power state of the drive recorder 1. In this example, when the drive recorder 1 is turned off (i.e., inactive) while the vehicle is stopped and then turned on (i.e., active) again, the control unit 19 determines that the shooting direction of the front-viewing camera 4 may have changed, and adjusts the cut-out position of the cut-out image Imc. As a result, the control unit 19 appropriately sets the cut-out position of the cut-out image Imc even when the angle of the rearview mirror 12 is changed while the drive recorder 1 is off and the contact with the drive recorder 1 cannot be detected by the contact sensor 5.

[0055] 7 is a flowchart showing the procedure of the process for adjusting the cut-out position of the cut-out image Imc according to Modification 1. The control unit 19 repeatedly executes the process of the flowchart shown in FIG.

[0056] First, the control unit 19 determines whether or not a command to turn off the drive recorder 1 has been received (step S301). For example, the control unit 19 determines whether or not a command to turn off the drive recorder 1 has been received by detecting an input to a power switch, which is the operation unit 9. Then, if the control unit 19 has not received a command to turn off the drive recorder 1 (step S301; No), it continues to execute step S301.

[0057] Then, when the control unit 19 receives a command to turn off the power of the drive recorder 1 (step S301; Yes), the control unit 19 determines whether the vehicle is stopped or not (step S302). If the vehicle is stopped (step S302; Yes), the control unit 19 proceeds to step S303. On the other hand, if the vehicle is not stopped (step S302; No), the control unit 19 determines that the cut-out position of the cut-out image Imc cannot be adjusted, and ends the processing of the flowchart.

[0058] Next, when it is confirmed that the vehicle is stopped, the control unit 19 stores the clipped image Imc taken immediately before the drive recorder 1 is powered off in the nonvolatile memory 15 (step S303). That is, the control unit 19 writes the latest clipped image Imc stored in the RAM 11 to the nonvolatile memory 15. Thereafter, the drive recorder 1 transitions to a power-off state.

[0059] Next, the control unit 19 determines whether or not a power-on command for the drive recorder 1 has been received (step S304). If the control unit 19 has received a power-on command for the drive recorder 1 (step S304; Yes), it determines whether or not the vehicle is stopped (step S305). If the vehicle is stopped (step S305; Yes), the control unit 19 determines the cut-out position of the cut-out image Imc in the forward image Im based on the cut-out image Imc stored in the nonvolatile memory 15 immediately before the power was turned off and the forward image Im currently supplied from the forward imaging camera 4 (step S306). In this case, the control unit 19 detects a common feature common to each image, as in the cut-out position adjustment process of FIG. 5, and adjusts the cut-out position of the cut-out image Imc based on the position of the common feature in each image. On the other hand, when the control unit 19 determines that the vehicle is not stopped (step S305; No), the control unit 19 ends the processing of the flowchart without adjusting the cut-out position of the cut-out image Imc.

[0060] 7, even if the angle of the rearview mirror 12 is changed while the drive recorder 1 is powered off and the contact sensor 5 cannot detect contact with the drive recorder 1, the cut-out position of the cut-out image Imc can be set appropriately. In the example of FIG. 7, the control unit 19 is an example of the "switching means" in the present invention.

[0061] In another example regarding the timing of adjusting the cut-out position, the control unit 19 may determine whether or not adjustment of the cut-out position is necessary based on the driver's seat occupancy information or seat belt fastening information acquired by the vehicle information acquisition unit 3.

[0062] For example, when using information about the driver's seat occupancy, the control unit 19 detects that the driver has left the driver's seat and then taken up in the driver's seat, and determines that the driver may have changed and adjusted the angle of the rearview mirror 12 (i.e., changed the shooting direction of the forward shooting camera 4). Therefore, in this case, the control unit 19 compares the cropped image Imc taken immediately before the driver left the driver's seat with the front image Im taken when the driver re-seated in the driver's seat, and adjusts the crop position of the cropped image Imc.

[0063] Furthermore, when using seat belt fastening information, if the control unit 19 detects that the driver's seat belt has been unfastened and then fastened again, it determines that there is a possibility that the driver has changed and the angle of the rearview mirror 12 has been adjusted. Therefore, in this case, the control unit 19 compares the cropped image Imc taken immediately before the seat belt is unfastened with the forward image Im taken when the seat belt is fastened again, and adjusts the crop position of the cropped image Imc.

[0064] (Variation 2) The front-view photographing camera 4 may be a camera with a fixed photographing direction. In this case, for example, the control unit 19 accepts an adjustment of the cropping position of the cropped image Imc based on an operation on the operation unit 9, and adjusts the cropped image Imc so that the center of the cropped image Imc initially coincides with a position in the traveling direction of the vehicle. Even in this case, the control unit 19 can automatically and appropriately adjust the cropping position of the cropped image Imc when the angle of the rearview mirror 12 is changed from the initial state while the vehicle is stopped.

[0065] (Variation 3) The drive recorder 1 may further include a camera that captures an image of the driver's seat, and may determine whether or not the cut-out position needs to be adjusted based on an image captured by the camera.

[0066] FIG. 8 shows a front view of the drive recorder 1A according to this modification. As shown in FIG. 8, the drive recorder 1A is provided with a rearward imaging camera 4R that faces in the positive direction of the Z axis, opposite to the front imaging camera 4. In this case, the imaging range of the rearward imaging camera 4R includes the driver's seat. The rearward imaging camera 4R is an example of the "second imaging means" in the present invention.

[0067] In this case, in a first example, the control unit 19 determines whether or not a person is sitting in the driver's seat based on an image captured by the rear-view imaging camera 4R (also referred to as a "driver's seat camera image"). Then, when the driver's seat camera image transitions from a state in which a person is captured to a state in which no person is captured, and then a person is captured again, the control unit 19 determines that the driver may have changed. Therefore, in this case, the control unit 19 compares the cropped image Imc taken immediately before the person leaves the driver's seat with the front image Im taken after the person has reseated the driver's seat, and adjusts the crop position of the cropped image Imc.

[0068] In a second example, the control unit 19 may identify the face (physical features) of the person sitting in the driver's seat based on the driver's seat camera image using a known image recognition technology, and if it determines that a person different from the person who sat in the driver's seat last time has sat in the driver's seat, it may adjust the cut-out position of the cut-out image Imc. In this case, the control unit 19 detects the face of the person sitting in the driver's seat based on the driver's seat camera image, and identifies the face of the person sitting in the seat by extracting predetermined feature information that indicates the features of the detected face.

[0069] (Variation 4) The drive recorder 1 may acquire information on whether the accessory power supply of the vehicle is on or off using the vehicle information acquisition unit 3, and may switch the power supply on or off in conjunction with the state of the accessory power supply of the vehicle.

[0070] 5, the control unit 19 determines that a request to power off the drive recorder 1 has been received if it determines that the accessory power of the vehicle has been switched from on to off based on the information acquired from the vehicle information acquisition unit 3. Similarly, in step S204, the control unit 19 determines that a request to power on the drive recorder 1 has been received if it determines that the accessory power of the vehicle has been switched from off to on based on the information acquired from the vehicle information acquisition unit 3. Then, the drive recorder 1 adjusts the cut-out position of the cut-out image Imc thereafter when the vehicle is stopped.

[0071] (Variation 5) In the above embodiment, the drive recorder 1 is provided with clamping portions 14A to 14D for clamping and holding the drive recorder 1 in the genuine rearview mirror 12 attached to the vehicle. Alternatively, the drive recorder 1 may not be provided with the clamping portions 14A to 14D, but may be built into the rearview mirror and be replaceable with the genuine rearview mirror attached to the vehicle.

[0072] In another example, the drive recorder 1 may be a navigation device that does not have a function of storing the clipped image Imc at the time of the accident occurrence in the non-volatile memory 15. In this case, the navigation device detects the lane, the lighting status of the traffic light, the preceding vehicle, etc. by performing image recognition processing on the clipped image Imc, and displays a text image, a graphic image, etc. based on the detection result on the display 10 by superimposing it on the clipped image Imc, or outputs audio information.

[0073] In yet another example, the drive recorder 1 is not limited to being attached to or built into a rearview mirror, but may also be applied to a navigation device integrated with a display installed on the dashboard of a vehicle, where the angle of the display can be changed to a direction that makes it easier for the passengers to see. [Explanation of symbols]

[0074] 1. Drive recorder 3 Vehicle information acquisition unit 4. Forward-facing camera 4R rear view camera 5 Contact Sensor 9 Control section 10. Display 11 RAM 12. Rearview mirror 15 Non-volatile memory 19 Control Unit

Claims

1. A photographing device mounted on a vehicle, an imaging means for imaging a scene ahead of the vehicle; an image control means for cutting out a partial range of a photographed image, which is an image photographed by the photographing means, as a cut-out image; a determination means for determining whether or not there is a possibility of changing the photographing direction of the photographing means based on information about the driver's seat of the vehicle; Equipped with The image control means adjusts the image cut-out range after the judgment when the judgment means judges that there is a possibility of change so that the position of the first object in the cut-out image before the judgment approximately matches the position of the first object in the cut-out image after the judgment.

2. The photographing device according to claim 1, characterized in that the determination means determines that there is a possibility of a change when information indicating a change in driver is obtained based on an image photographed by a second photographing means that photographs the driver's seat of the vehicle.

3. 2. The photographing device according to claim 1, wherein the determining means determines that there is a possibility of a change when information indicating that the driver's seat of the vehicle has changed from an unoccupied state to an occupied state is acquired.

4. 2. The photographing device according to claim 1, wherein the determining means determines that there is a possibility of change when information indicating that the seat belt of the driver's seat of the vehicle has changed from an unfastened state to a fastened state is acquired.

5. A photographing device mounted on a vehicle, an imaging means for imaging a scene ahead of the vehicle; an image control means for cutting out a partial range of a photographed image, which is an image photographed by the photographing means, as a cut-out image; a determining means for determining whether or not there is a possibility of changing the photographing direction of the photographing means based on information about the operating state of the photographing device; Equipped with the determination means determines that there is a possibility of change when information indicating that the photographing device has changed from an operating state to a non-operating state and then changed back to an operating state is acquired; The image control means adjusts the image cut-out range after the judgment when the judgment means judges that there is a possibility of change so that the position of the first object in the cut-out image before the judgment approximately matches the position of the first object in the cut-out image after the judgment.

6. The vehicle is characterized in that the rearview mirror is built in or attached to the rearview mirror. The photographing device according to any one of claims 1 to 5.

7. A control method executed by an imaging device that is mounted on a vehicle and has imaging means that captures an image ahead of the vehicle, comprising: an image control step of cutting out a partial range of the image captured by the image capturing means as a cut-out image; a determination step of determining whether or not there is a possibility of a change in the photographing direction of the photographing means based on information about the driver's seat of the vehicle; and The image control process is a control method characterized in that, when the judgment process determines that there is a possibility of change, the image cropping range after the judgment is adjusted so that the position of the first object in the cropped image before the judgment approximately matches the position of the first object in the cropped image after the judgment.

8. A program executed by a computer of an imaging device that is mounted on a vehicle and has imaging means for imaging a scene ahead of the vehicle, The computer an image control means for cutting out a partial range of the image captured by the image capturing means as a cut-out image; and functioning as a determination means for determining whether or not there is a possibility of a change in the photographing direction of the photographing means based on information about the driver's seat of the vehicle; The image control means is a program characterized in that, when the judgment means judges that there is a possibility of change, it adjusts the image cropping range after the judgment so that the position of the first object in the cropped image before the judgment approximately matches the position of the first object in the cropped image after the judgment.

9. A control method executed by an imaging device that is mounted on a vehicle and has imaging means that captures an image ahead of the vehicle, comprising: an image control step of cutting out a partial range of the image captured by the image capturing means as a cut-out image; a determining step of determining whether or not there is a possibility of changing the photographing direction of the photographing means based on information about the operating state of the photographing device; and the determining step determines that there is a possibility of change when information indicating that the photographing device has changed from an operating state to a non-operating state and then changed back to an operating state is acquired; The image control process is a control method characterized in that, when the judgment process determines that there is a possibility of change, the image cropping range after the judgment is adjusted so that the position of the first object in the cropped image before the judgment approximately matches the position of the first object in the cropped image after the judgment.

10. A program executed by a computer of an imaging device that is mounted on a vehicle and has imaging means for imaging a scene ahead of the vehicle, The computer an image control means for cutting out a partial range of the image captured by the image capturing means as a cut-out image; and functioning as a determination means for determining whether or not there is a possibility of changing the photographing direction of the photographing means based on information about the operating state of the photographing device; the determination means determines that there is a possibility of change when information indicating that the photographing device has changed from an operating state to a non-operating state and then changed back to an operating state is acquired; The image control means is a program characterized in that, when the judgment means judges that there is a possibility of change, it adjusts the image cropping range after the judgment so that the position of the first object in the cropped image before the judgment approximately matches the position of the first object in the cropped image after the judgment.

11. 11. A storage medium storing the program according to claim 8 or 10 in a computer-readable manner.

Images