JP6536032B2 - In-vehicle camera - Google Patents

Description

  The present invention relates to an in-vehicle camera, and more particularly to an in-vehicle camera with an improved white balance adjustment.

  Conventionally, side mirrors are used for safety confirmation of the rear left and right of a car. In recent years, there has been a trend to use an imaging device as a side mirror alternative camera instead of the side mirror. When an imaging device is used as a substitute for a mirror, it is necessary to image the range which has been captured by a conventional side mirror with the imaging device. The conventional side mirror is capable of adjusting the vertical and horizontal angles according to the driver's height and the range to be checked. For this reason, it is necessary to image a wider range including the adjustment range of the conventional side mirror with an imaging device. In this case, the installation position of the imaging device is determined such that the road surface behind the left and right of the vehicle, obstacles such as curbs, and a part of the vehicle body of the vehicle are included in the imaging range.

  Generally, in the imaging apparatus, auto white balance processing for automatically adjusting the white balance of a captured image is performed. In particular, in an in-vehicle imaging apparatus, the red (R) signal and the blue (B) signal are set to be the same level as the red (R) signal or the blue (B) signal with reference to the green (G) signal level of the entire screen. Automatic white balance processing for adjusting the gain is performed (for example, Patent Document 1).

JP-A-8-18995 [0004] to [0007], [Fig. 5]

  An on-vehicle imaging device such as a side mirror alternative camera or a back camera is used with at least a part of the vehicle body of the vehicle set in the imaging range. At this time, auto white balance processing is performed on the entire captured image including a part of the vehicle body of the own vehicle. Since auto white balance processing is processing that automatically corrects the total value of each color component of RGB of the whole captured image uniformly, if part of the vehicle body of the vehicle is within the imaging range, There is a problem that it is affected by the color and the captured image other than a part of the vehicle body of the own vehicle does not become the optimal white balance.

  More specifically, when the color of a part of the vehicle body of the vehicle that falls within the imaging range is red (R), the auto white balance processing of the imaging device performs processing for reducing the red (R) gain. As a result, the image in the imaging region other than a part of the vehicle body of the own vehicle is deteriorated in color reproduction of red (R) and becomes an image in which blue (B) and green (G) are emphasized.

  The present invention has been made in view of the above problems, and it is an object of the present invention to provide an on-vehicle camera capable of appropriately performing auto white balance processing even when part of the vehicle body of the vehicle is in the imaging range. I assume.

  In order to achieve the above object, an on-vehicle camera according to an aspect of the present invention is mounted on a vehicle and captures an image of the periphery of the vehicle and a part of the vehicle body. For each predetermined color information of the vehicle body A data storage unit in which adjustment data of white balance of a captured image is stored, and when color information is input, the adjustment data corresponding to the input color information is read from the data storage unit, and the adjustment data read out And an image processing unit that adjusts the white balance of the captured image based on the

  In this on-vehicle camera, the image processing unit reads adjustment data corresponding to the input color information of the vehicle from the data storage unit, and performs auto white balance processing of the captured image based on the adjustment data. It is possible to prevent the color of a part of the vehicle body of the entering vehicle from affecting the auto white balance processing and preventing the captured image from becoming an optimum white balance.

  The on-vehicle camera may further include a control unit that receives the color information selected by the user from the outside and outputs the color information to the image processing unit.

  According to the present invention, even when a part of the vehicle body of the host vehicle falls within the imaging range, it is possible to perform auto white balance processing of an optimal captured image.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the structure of the whole vehicle-mounted camera system which is embodiment which concerns on this invention. It is a block diagram which shows the functional structure of the vehicle-mounted camera in the vehicle-mounted camera system of FIG. It is a figure which shows the example of an imaging including a part of vehicle body of the vehicle by the vehicle-mounted camera of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, the configuration of an on-vehicle camera system using an on-vehicle camera according to an embodiment of the present invention will be described.
FIG. 1 is a view showing the overall configuration of an on-vehicle camera system according to an embodiment of the present invention.

  As shown in the figure, the on-vehicle camera system 1 includes left and right on-vehicle cameras 100L and 100R, a controller 200, and left and right monitors 300L and 300R.

  The on-vehicle cameras 100L and 100R are mounted at positions before the drivers on both the left and right sides of the vehicle D, and pick up images of the left and right rear of the vehicle D. That is, the on-vehicle camera system 1 is used as a means to replace the left and right side mirrors of the vehicle D.

  The controller 200 is configured by a microcomputer or the like. The controller 200 may be realized as part of the function of an electronic control unit that controls each part of the vehicle D mounted on the vehicle D. The controller 200 controls the in-vehicle cameras 100L and 100R and the monitors 300L and 300R, and projects the images captured by the left and right in-vehicle cameras 100L and 100R on the corresponding monitors 300L and 300R in real time.

  As shown in the figure, when the in-vehicle cameras 100L and 100R and the monitors 300L and 300R are installed, the controller 200 sets the image of the left in-vehicle camera 100L on the left monitor 300L and the image of the right in-vehicle camera 100R on the right Project on the 300R.

  The monitors 300L and 300R display the images captured by the on-vehicle cameras 100L and 100R.

[About in-vehicle camera]
Next, the configuration of the on-vehicle cameras 100L and 100R in the on-vehicle camera system 1 will be described.

  FIG. 2 is a block diagram showing a configuration of one of the on-vehicle cameras 100L and 100R in the on-vehicle camera system 1. The configurations of the two on-vehicle cameras 100L and 100R are the same. Hereinafter, the one on-vehicle camera is referred to as “on-vehicle camera 100”.

  As shown in the figure, the on-vehicle camera 100 includes a lens 11 for imaging a subject, a CCD (Charge Coupled Device) image sensor for photoelectrically converting the imaged subject image, a CMOS (Complementary Metal Oxide Semiconductor) image sensor, etc. And a pre-signal processing unit 13 that generates RAW data by performing A / D conversion and defect pixel correction of signals converted by the image sensor 12.

  In addition, the on-vehicle camera 100 performs various signal processing such as auto white balance processing on the RAW data output from the pre-signal processing unit 13, and each color information of the vehicle body of the vehicle D And an encoder 16 for converting the image data processed by the image processing unit 14 into a video format according to the output format.

  Furthermore, the on-vehicle camera 100 has a camera controller 17. The camera controller 17 transmits image data format converted by the encoder 16 from the video output terminal 18 to the controller 200 of the in-vehicle camera system 1, and is selected and input by the user from the controller 200 of the in-vehicle camera system 1. Processing such as receiving color information of the vehicle body through the external communication terminal 19 and notifying the image processing unit 14 is performed.

[About adjustment data in auto white balance processing]
As factors to determine the adjustment data of the auto white balance, there are the color of the vehicle body and the ratio of the vehicle body to the imaging range of the on-vehicle camera 100. As shown in FIG. 3, the proportion of the image 22 of the vehicle body in the imaging range 21 of the on-vehicle camera 100 is always constant and does not change. Adjustment data according to the color of the vehicle body, which is another element, is created in advance by the provider of the on-vehicle camera 100 and stored in the data storage unit 15. Specifically, the adjustment data is composed of gain values for each RGB.

[Operation of auto white balance processing]
Next, based on the adjustment data stored in the data storage unit 15, a series of operations of the auto white balance processing will be described.

  First, the user uses the user interface of the controller 200 of the in-vehicle camera system 1 to input the color of the vehicle body of the vehicle D. A graphical user interface is employed as the user interface. The graphical user interface displays all the color information associated with the adjustment data stored in the data storage unit 15 of the on-vehicle camera 100 in a selectable state, so that the user corresponds to the color of the vehicle body of the own vehicle By selecting color information, color information is input.

  When the controller 200 of the in-vehicle camera system 1 receives the color information of the vehicle body of the vehicle D input by the user, the controller 200 outputs the color information of the selected vehicle body to the camera controller 17 of the in-vehicle camera 100.

  When color information of the vehicle body of the vehicle D is input from the controller 200 of the in-vehicle camera system 1, the camera controller 17 of the in-vehicle camera 100 outputs the color information to the image processing unit 14.

  When receiving the color information of the vehicle body of the vehicle D from the camera controller 17, the image processing unit 14 reads the adjustment data associated with the color information from the data storage unit 15, and adjusts the white balance based on the adjustment data. That is, the gain adjustment for each RGB is performed. At this time, for example, when the color of the vehicle body is red (R), the gain of red (R) is set higher than the gain of green (G). As a result, the image processing unit 14 can adjust the white balance of the optimum captured image that is not affected by the color of the vehicle body on the RAW data output from the pre-signal processing unit 13. Even when part of the vehicle body of the vehicle D is included, it is possible to appropriately perform auto white balance processing of a captured image.

<Modification>
Note that the white balance adjustment according to the color of the vehicle body of the above-mentioned vehicle D makes red (R) signal or blue (B) signal the same level with reference to green (G) signal level of the whole screen The same may be applied to the initial adjustment of auto white balance to adjust the gains of R) and blue (B).

  Although the above embodiment describes the on-vehicle camera 100 replacing the side mirror of the vehicle D, the present invention is a back camera that is attached to a part of the vehicle body of the own vehicle and that takes a part of the vehicle body of the own vehicle as an imaging range It can be applied to all types of in-vehicle cameras.

  Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various changes and modifications may be made within the scope of the subject matter of the present invention described in the claims. Is possible.

D: Vehicle 14: Image processing unit 15: Data storage unit 17: Camera controller 100, 100L, 100R: In-vehicle camera

Claims (2)

The in-vehicle cameras mounted on a vehicle to capture a portion of the vehicle body around and the vehicle of the vehicle,
A data storage unit in which white balance adjustment data of a captured image is stored for each of a plurality of predetermined color information;
When the color information of the vehicle body is input, the adjustment data corresponding to the input color information of the vehicle body is read from the data storage unit, and the color of the vehicle body is read based on the read adjustment data. An image processing unit configured to adjust a white balance of the captured image such that a gain of color information based on information becomes higher than a gain of color information other than the color information of the vehicle body . The on-vehicle camera according to claim 1,
A control unit which receives the color information of the vehicle body from the outside and outputs the color information to the image processing unit.

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