JP2014068328A - Camera attached-matter detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a camera attached-matter detection device capable of reliably detecting an attached matter even if it is attached to any portion of a camera.SOLUTION: A camera 2 oriented toward the outside of a vehicle to capture a periphery of the vehicle is oriented toward the inside of the vehicle by a camera driving unit 4, and a reference image on a reference image drawn board 3 mounted on the vehicle is captured in the whole imaging range. An attached-matter detection unit 9 compares captured image data obtained by capturing the reference image with reference image data stored in advance in a reference image storage unit 8 to detect the presence/absence of a change in an image, thereby determining the presence/absence of an attached matter on the camera 2.

Description

  The present invention relates to a camera adhering matter detection device that detects when an adhering matter such as water droplets or dust adheres to a camera that captures the periphery of a moving body.

  For example, Patent Documents 1 and 2 have been proposed as techniques for determining the presence or absence of an adhering substance attached to a camera using an image captured by a camera mounted on the vehicle.

  In the vehicle back monitor device according to Patent Document 1, an image of a part of a vehicle (actual image) reflected in a part of the camera and a reference image corresponding to the actual image when no deposit is attached to the camera are obtained. By comparing and detecting the presence or absence of a change in the image, the presence or absence of a deposit on the camera is determined.

  In the imaging apparatus according to Patent Document 2, a plurality of images captured at different timings using a camera are compared at each corresponding pixel, and one maximum is obtained using a pixel having a maximum density difference between pixels. A difference image is formed, and a pixel having a density equal to or lower than a threshold in the maximum difference image is determined as a dirty pixel (that is, a deposit).

JP 2008-265727 A JP 2007-318355 A

  In the method of Patent Document 1, a part in which a difference occurs in a captured image is determined as an attached object on the assumption that an image of a part of a vehicle captured in a part of a camera does not change. For this reason, there is a problem that the adhering matter can be detected only when there is an adhering matter in the image portion that shows a part of the vehicle, and the presence or absence of the adhering matter cannot be detected in the image portion that does not show a part of the vehicle. It was.

  In the method of the above-mentioned patent document 2, on the premise that the deposit is present at the same place, a portion in the captured image where no difference occurs is determined as the deposit. Therefore, there has been a problem that it is impossible to detect a deposit such as raindrops that can move on the camera.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a camera adhering matter detection device capable of reliably detecting an adhering matter on any part of the camera. .

  A camera adhering matter detection apparatus according to the present invention is a camera that is installed on a moving body and has a plate member on which an arbitrary reference image is drawn, and a camera that is installed on the moving body and images the surroundings of the moving body. A reference image storage unit that stores reference image data in which the reference image is captured in the entire imaging range with the camera imaging direction being directed to the reference image in advance. At this timing, the camera image direction is directed to the reference image, and the captured image data obtained by capturing the reference image over the entire imaging range is compared with the reference image data stored in the reference image storage unit. And an adhering matter detecting unit for detecting the presence or absence of adhering matter on the camera.

  According to this invention, when determining the presence or absence of deposits, the imaging direction of the camera is changed, the reference image is captured over the entire imaging range, and compared with the reference image captured in advance. It is possible to provide a camera adhering matter detection device capable of reliably detecting an adhering matter on any part of the camera.

It is a block diagram which shows the structure of the camera deposit | attachment detection apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows a mode that the camera unit of the camera adhering matter detection apparatus which concerns on Embodiment 1 was attached to the vehicle rear part of a motor vehicle. FIG. 3 is an enlarged vehicle sectional view of the periphery of the camera unit of FIG. 2. It is a figure which shows an example of the reference image data which the reference image memory | storage part of the camera adhering matter detection apparatus which concerns on Embodiment 1 has memorize | stored. It is a figure which shows an example of the picked-up image data which imaged the reference image at the time of execution of the deposit | attachment detection mode of the camera deposit | attachment detection apparatus which concerns on Embodiment 1. FIG. 4 is a flowchart showing the operation of the camera deposit detection apparatus according to Embodiment 1.

Embodiment 1 FIG.
The camera adhering matter detection apparatus shown in FIG. 1 shows a configuration example in the case of being incorporated as a part of an in-vehicle information device that captures an image of the vehicle periphery with the camera 2 and displays it on the display unit 13. The camera attached matter detection apparatus includes a camera unit 1, a reference image storage unit 8, an attached matter detection unit 9, a control unit 10, an input unit 11, a drawing unit 12, a display unit 13, and an audio output unit 14. The camera unit 1 includes a camera 2, a reference image drawing plate (plate member) 3, a camera drive unit 4, a camera drive control unit 5, an air injection unit 6, and an air injection control unit 7.

  FIG. 2 shows a state in which the camera unit 1 is attached to the rear part of the vehicle, and FIG. 3 shows a vehicle cross-sectional view in which the periphery of the camera unit 1 is enlarged. The camera 2 in the illustrated example is a rear camera that is installed at the rear of the vehicle and images the rear of the vehicle. The camera 2 is attached to the vehicle side via a rotating shaft 2a and is rotatable with respect to the vehicle. The camera drive control unit 5 operates the camera drive unit 4 in accordance with an instruction from the control unit 10, and the camera drive unit 4 rotates the camera 2 around the rotation axis 2a to change the imaging direction to the vehicle exterior side (FIG. 3 ( a)) and the vehicle interior (FIG. 3B).

In addition to using the camera unit 1 as a rear camera, the camera unit 1 can be used as a front camera that attaches to the front of the vehicle and images the front of the vehicle, or it can attach to the side of the vehicle and use as a side camera that images the side of the vehicle. Is also possible. It is also possible to connect a plurality of camera units 1 to the camera deposit detection device.
Further, the camera 2 is not limited to a camera mounted on an automobile, and may be a camera mounted on a moving body such as a railway or a ship.

  The reference image drawing plate 3 is a plate member on which an arbitrary reference image is drawn, and is installed in a console between the inside and outside of the vehicle as shown in FIG. 3, and is imaged when the camera 2 faces the inside of the vehicle. It is possible arrangement. The arrangement is such that the reference image appears in the entire imaging range of the camera 2. By installing the reference image drawing plate 3 in a semi-enclosed space other than the rotating opening of the camera 2 such as a console, dust and the like are less likely to adhere to the surface of the reference image, and erroneous detection of the adhering matter can be suppressed. .

  In the center of the reference image drawing plate 3, an injection port 6a of the air injection unit 6 penetrates. The air injection control unit 7 operates the air injection unit 6 in response to an instruction from the control unit 10, and the air injection unit 6 injects air from the injection port 6 a and adheres to the lens 2 b of the camera 2 such as water droplets and dust. Blow away deposits. The injection port 6a may be disposed at a position other than the center of the reference image drawing plate 3 as long as it is a position where air can be injected to the lens 2b.

FIG. 4 shows an example of reference image data 3 a obtained by capturing the reference image of the reference image drawing board 3 with the camera 2. Here, as a reference image, a grid-like image of a blackboard in which black lines perpendicular to the vertical and horizontal directions are drawn on a white background is used. Therefore, the reference image data 3a obtained by capturing the image is also shown in FIG. It is eye-shaped image data, and an injection port 6a is shown in the center.
When no adhering matter is attached to the lens 2b of the camera 2, the camera 2 is pointed toward the inside of the vehicle and a reference image is imaged over the entire imaging range, and this is stored in the reference image storage unit 8 as reference image data 3a. deep.

  The adhering matter detection unit 9 captures the captured image data of the reference image drawing plate 3 captured by the camera 2 facing the inside of the vehicle and the reference image data stored in advance in the reference image storage unit 8 when executing the adhering matter detection mode. 3a is compared and the presence or absence of the change of an image is detected. As a result, if a change is detected between the images, it is determined that the attached matter is attached, and if no change is detected, it is determined that the attached matter is not attached. By comparing the reference image data 3a captured in the entire imaging range of the camera 2 and the captured image data 3b, it is possible to detect any portion of the lens 2b of the camera 2 where there is an attachment.

  Here, FIG. 5 shows an example of captured image data 3b obtained by capturing the reference image drawing board 3 with the camera 2 when the attached matter detection mode is executed. If dust is attached to the lens 2b of the camera 2, the attached matter 20 whose shade color has changed appears in the captured image data 3b. Further, if water droplets are attached to the lens 2b of the camera 2, the attached matter 21 that appears as distortion of vertical and horizontal lines is shown in the captured image data 3b. Therefore, the adhering matter detection unit 9 detects the difference between the reference image data 3a and the captured image data 3b, such as a change in gray color and distortion of the vertical and horizontal lines, and determines that the adhering matter is attached when the difference is detected. can do.

  By using a grid-like image as a reference image to be drawn on the reference image drawing board 3, it becomes easy to detect changes in shades of blocks and vertical / horizontal line distortion divided into grid-like grids, and fine dust In addition, it is possible to detect water droplets and the like. However, in addition to a grid-like image, any image can be used as long as it is an image that can determine the presence or absence of an adhering matter by the adhering matter detection unit 9, such as a horizontal stripe pattern or a vertical stripe pattern. Good.

  The control unit 10 is a CPU (Central Processing Unit) that controls the operation of the camera deposit detection apparatus. The control unit 10 receives an adhering matter detection result from the adhering matter detection unit 9. Further, information from the vehicle side such as an on / off signal of an ignition switch of the vehicle and a shift R operation signal generated when the shift lever is set to reverse (R) is also input to the control unit 10. In addition, information on operation input performed by the user on the input unit 11 is input to the control unit 10. Based on the input information, the control unit 10 outputs an instruction to change the orientation of the camera 2 to the camera drive control unit 5 or outputs an air injection instruction to the air injection control unit 7.

  In addition, the control unit 10 notifies the user of the attached matter detection result of the attached matter detection unit 9. The notification is performed by either one or both of display and voice guidance. In the case of notification by display, the control unit 10 issues an instruction to the drawing unit 12, and the drawing unit 12 draws a screen indicating that the attached matter is attached to the lens 2 b of the camera 2 and displays the screen on the display unit 13. When notifying by voice guidance, voice guidance data prepared in advance is output from the voice output unit 14.

  Next, the operation of the camera deposit detection apparatus will be described with reference to the flowchart shown in FIG. In the following description, the camera unit 1 is attached to the rear part of the vehicle and used as a rear camera. In addition, it is assumed that the input unit 11 and the display unit 13 are configured as an integrated device using a touch display.

  When the ignition switch ON signal is input from the vehicle, the camera deposit detection device is started. When the shift lever is switched to R and a shift R operation signal is input from the vehicle to the control unit 10 (step ST1), the control unit 10 starts an adhering matter detection mode (step ST2).

  In this attached matter detection mode, according to an instruction from the control unit 10, the camera 2 faces the inside of the vehicle and starts imaging the reference image drawing plate 3. Further, the control unit 10 sets the number x of retries for removing the deposits = 3 (step ST3). In this example, the number of retries x is three, but any number may be used. Subsequently, the adhering matter detection unit 9 compares the reference image data 3a stored in the reference image storage unit 8 with the captured image data 3b currently being imaged, and determines the presence or absence of adhering matter (step ST4).

  When the deposit is not detected (step ST4 “NO”), the control unit 10 starts the standard mode (step ST5). In the standard mode, according to an instruction from the control unit 10, the camera 2 faces the outside of the vehicle and starts imaging the rear of the vehicle. The captured image data behind the vehicle imaged by the camera 2 is displayed on the display unit 13.

  When the shift lever is switched from R to another mode and no shift R operation signal is input from the vehicle to the control unit 10 (step ST6), the control unit 10 moves to the camera drive control unit 5 and the camera 2 moves to the inside of the vehicle. An instruction to turn is output (step ST7). Thereby, while the shift lever is switched to a drive or the like and the camera 2 is not used, the lens 2b can be directed toward the inside of the vehicle to prevent water droplets and dust from adhering.

  On the other hand, when the deposit is detected (step ST4 “YES”), the control unit 10 confirms the number of retries x (step ST8), and if the current number of retries x is greater than 0 (step ST8 “YES”). Then, air is ejected from the air ejecting section 6 to try to remove the deposit (step ST9). Moreover, the control part 10 decrements the retry frequency x after air injection (step ST10).

  If the adhered matter continues to be detected even after the air injection is repeated three times (step ST4 “YES”), the number of retries x is zero (step ST8 “NO”). The camera 2 is notified that there is a deposit on the screen and voice guidance (step ST11). Subsequently, an instruction is issued from the control unit 10 to the drawing unit 12, and an air injection operation button is displayed on the display unit 13 of the touch display (step ST12). When the user depresses the air injection operation button, the depressing operation is received by the input unit 11 and input to the control unit 10 (step ST13), and the control unit 10 increments the retry count x to x = 1 (step ST14). Air is jetted from the air jetting unit 6 (step ST9). And the control part 10 decrements the frequency | count x of retry after air injection according to a user instruction | indication, and is set to x = 0 (step ST10).

  The control unit 10 repeats steps ST4 “YES”, ST8 “NO”, ST11 to ST14, ST9, and ST10, and repeats air injection according to a user instruction until no adhered matter is detected. In addition, when the deposits cannot be removed by repeating the air injection according to the user instruction for a predetermined time or a predetermined number of times, the process may be advanced to the standard mode of step ST5.

  In the flowchart of FIG. 6, when the rear camera is started when the shift lever is switched, the adhering matter detection mode is first executed to shift to the standard mode. However, the timing for executing the adhering matter detection mode is limited to this. Is not to be done. Moreover, what is necessary is just to perform the deposit | attachment detection mode at arbitrary timing also about camera units 1 other than a rear camera.

  As described above, according to the first embodiment, the camera adhering matter detection device is installed in the vehicle, the reference image drawing board 3 on which an arbitrary reference image is drawn, and the camera that is installed in the vehicle and images its surroundings. The camera unit 1 capable of capturing a reference image by changing the image capturing direction 2 by the camera driving unit 4 and reference image data obtained by capturing the reference image in the entire image capturing range in advance with the image capturing direction of the camera 2 directed toward the reference image. Reference image storage unit 8 storing 3a, and captured image data 3b obtained by capturing the reference image in the entire imaging range with the imaging direction of the camera 2 directed to the reference image at an arbitrary timing, and the reference image storage unit 8 Is compared with the reference image data 3a stored in the I configured the presence or absence of garment to comprise a determining attached matter detection unit 9. For this reason, it is possible to provide a camera adhering matter detection device that can reliably detect an adhering matter on any part of the camera 2. Further, by making the camera 2 movable, the camera 2 can be directed toward the outside of the vehicle only when necessary, and can be prevented toward the inside of the vehicle when not in use.

  In addition, according to the first embodiment, the camera deposit detection device uses the grid-like image of the grid as the reference image, so that the grid-like grid of the captured image data 3b obtained by capturing the reference image is used. It is possible to detect fine dust that appears as a change in shading color on a block that is divided into two, fine water droplets that appear as distortion of vertical and horizontal lines, and the like.

  Further, according to the first embodiment, since the reference image drawing plate 3 is not exposed to the outside of the vehicle, it is possible to prevent the deposit from adhering to the reference image drawing plate 3. Accordingly, it is possible to prevent erroneous detection such as detection of an attachment on the reference image drawing plate 3 as an attachment on the camera 2.

  Further, according to the first embodiment, when the attached matter detection device determines that the attached matter is attached by the attached matter detection unit 9, the camera attached matter detection unit 9 ejects air to the camera 2 and attempts to remove the attached matter. It was set as the structure provided with the injection part 6. FIG. For this reason, it is possible to remove water droplets and the like attached to the camera 2 during rainy weather and prevent deterioration of visibility.

  In the present invention, any constituent element of the embodiment can be modified or any constituent element of the embodiment can be omitted within the scope of the invention.

  1 camera unit, 2 camera, 2a rotation axis, 2b lens, 3 reference image drawing board, 3a reference image data, 3b captured image data, 4 camera drive unit, 5 camera drive control unit, 6 air injection unit, 6a injection port, 7 Air injection control unit 8 Reference image storage unit 9 Adhered matter detection unit 10 Control unit 11 Input unit 12 Drawing unit 13 Display unit 14 Audio output unit 20, 21 Adhered matter

Claims (4)

A board member with an arbitrary reference image installed on the moving body,
A camera that is installed on the moving body and images the surroundings of the moving body, and is capable of capturing the reference image by changing an imaging direction;
A reference image storage unit that stores reference image data in which the reference image is captured in the entire imaging range with the imaging direction of the camera directed toward the reference image in advance,
At an arbitrary timing, the captured image data obtained by capturing the reference image in the entire imaging range is compared with the reference image data stored in the reference image storage unit with the imaging direction of the camera directed toward the reference image. A camera adhering matter detection apparatus comprising: an adhering matter detecting unit that detects presence or absence of an adhering matter of the camera by detecting presence or absence of an image change.   2. The camera deposit detection apparatus according to claim 1, wherein the reference image is a grid-like image.   The camera adhering matter detection apparatus according to claim 1, wherein the plate member is not exposed to the outside of the moving body.   2. The apparatus according to claim 1, further comprising an air injection unit that injects air to the camera and attempts to remove the attached matter when the attached matter detecting unit determines that the attached matter is attached. 4. The camera deposit detection apparatus according to claim 1.

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