Video display device

Abstract

To provide a technology capable of appropriately displaying an object.SOLUTION: A video display device includes a camera having a wide-angle lens that captures a two-dimensional wide-angle image of the surroundings of a vehicle, a sensor that measures the distance to an object in a real space around the vehicle, a controller connected to the camera and the sensor, and a display device that displays the image on the basis of a signal output from the controller, and the controller is configured to calculate the position of the object in the wide-angle image captured by the camera on the basis of the distance to the object in the real space measured by the sensor, and to correct distortion of the wide-angle image such that the calculated position of the object in the wide-angle image is horizontal on the screen of the display device.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a video display device.

Background Art

[0002] Patent Document 1 discloses an apparatus for displaying an image of the periphery of a vehicle. This apparatus includes a camera having a wide-angle lens mounted on a corner or a license plate of the vehicle, a processing unit that corrects distortion of an image captured by the camera, and a display that displays the corrected image.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the image corrected by the apparatus described in Patent Document 1, there is a risk that an object to be noted may be distorted. Correction of image distortion is realized by stretching an image area around a predetermined position so that a predetermined position on the image becomes horizontal. For this reason, when an object to be noted is displayed outside a predetermined position, there is a risk that the object to be noted may be distorted. The present disclosure provides a technique capable of appropriately displaying an object.

Means for Solving the Problems

[0005] A video display device according to an aspect of the present disclosure includes a camera having a wide-angle lens that captures a two-dimensional wide-angle video of the periphery of a vehicle, a sensor that measures the distance to an object in the real space around the vehicle, a controller connected to the camera and the sensor, and a display device that displays a video based on a signal output from the controller. The controller calculates the position of an object in the wide-angle video captured by the camera based on the distance to the object in the real space measured by the sensor, and corrects the distortion of the wide-angle video so that the position of the object in the calculated wide-angle video is horizontal on the screen of the display device.

Advantages of the Invention

[0006] According to the present disclosure, a technique for appropriately displaying an object is provided.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0008] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0009] [Configuration of Vehicle] FIG. 1 is a block diagram showing an example of the configuration of a vehicle equipped with a video display device according to an embodiment. As shown in FIG. 1, the video display device 1 is mounted on a vehicle 2 as an example. The vehicle 2 may be a vehicle driven by a driver or an autonomous vehicle. The video display device 1 is used, for example, for parking assistance or for checking the traffic on the left and right when the front end of the vehicle 2 is extended into an intersection with poor visibility to check the traffic.

[0010] The vehicle 2 includes a camera 10, a distance measuring sensor 11, a controller 12, and a display device 13.

[0011] The camera 10 is a camera that images the periphery of the vehicle 2. The camera 10 is provided in front of the vehicle 2 as an example. The camera 10 may be provided behind the vehicle 2. The camera 10 has a wide-angle lens and images a two-dimensional wide-angle video of the periphery of the vehicle 2. The wide-angle lens is a lens with an angle of view of about 60° or more and includes a fish-eye lens. The wide-angle video may be a moving image or a still image. The wide-angle video includes distortion according to the wide-angle lens.

[0012] The distance measuring sensor 11 is a sensor that measures the distance to an object in the real space around the vehicle 2. The distance measuring sensor 11 may be a sensor using Lidar, a sensor using millimeter waves, a sensor using ultrasonic waves, or a stereo camera.

[0013] The controller 12 has a function of overall controlling the video display device 1. The controller 12 is configured as an ECU (Electronic Control Unit) as an example. The ECU is an electronic control unit having a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a CAN (Controller Area Network) communication circuit, etc. The controller 12 corrects the wide-angle video imaged by the camera 10 and causes the corrected wide-angle video to be displayed on the screen of the display device 13. The display device 13 is a device that displays video based on a signal output from the controller 12 and is, for example, a display.

[0014] The controller 12 is connected to the camera 10 and the distance measurement sensor 11. The controller 12 acquires a wide-angle video from the camera 10 and determines whether or not there is an object around the vehicle 2 based on the measurement result of the distance measurement sensor 11. When there is an object around the vehicle 2, the controller 12 calculates the position of the object in the wide-angle video imaged by the camera 10 based on the measured distance to the object in the real space. As a specific example, the controller 12 calculates the coordinate points of the object on the two-dimensional wide-angle video based on the relationship between the measured distance to the object in the real space and the viewing angle of the camera 10. Thereby, the controller 12 can calculate the position of the object in the distorted two-dimensional wide-angle video. Note that the controller 12 may learn the appearance of the object due to the distortion of the wide-angle video of the camera 10 and directly acquire the position of the object from the camera 10.

[0015] The controller 12 corrects the distortion of the wide-angle video so that the position of the object in the two-dimensional wide-angle video is horizontal on the screen of the display device 13. A technique for making the reference position of the wide-angle video horizontal can adopt a known technique.

[0016] When there is no object around the vehicle 2, the controller 12 corrects the distortion of the wide-angle video so that a predetermined position in the wide-angle video is horizontal on the screen of the display device 13. The predetermined position may be the position of the optical axis or the center of the image.

[0017] [An Example of Distortion Correction of Wide-Angle Video] FIG. 2 is an example showing the situation in the real space. In the example shown in FIG. 2, there are four lines and an object OB in front of the vehicle 2 as the imaging target. The four lines are, in order from the back to the front, the first line RL1, the second line RL2, the third line RL3, and the fourth line RL4. An example of the four lines is a lane boundary line. The object OB is a moving object as an example, and more specifically, a vehicle as an example. The object OB is positioned so as to appear overlapping with the first line RL1. In the example shown in FIG. 2, four lines and one object are shown to easily illustrate the distortion of the video, but the imaging target is not limited to these.

[0018] First, the situation where the object OB shown in FIG. 2 does not exist will be outlined. That is, the situation where the four lines are the imaging target. In this situation, the controller 12 corrects the distortion of the wide-angle video so that a predetermined position in the wide-angle video is horizontal on the screen of the display device 13. As an example, assume that the predetermined position is the position where the third line RL3 is displayed.

[0019] FIG. 3 is an example of a screen for displaying a wide-angle video corrected based on a predetermined position. On the screen V1 shown in FIG. 3, the position of the third line image VR3, which is an image corresponding to the third line RL3, is displayed horizontally on the screen V1. As a result, the third line image VR3 is displayed as a straight line. The first line RL1 and the second line RL2 are located deeper than the third line RL3. For this reason, the corresponding first line image VR1 and second line image VR2 are displayed above the third line image VR3 on the screen V1. However, since the video area above the third line image VR3 is stretched to make the third line image VR3 straight, it will be distorted in a form that is pulled upward. For this reason, the first line image VR1 and the second line image VR2 do not become straight and become line images that are curved and protrude upward. The fourth line RL4 is located in front of the third line RL3. For this reason, the corresponding fourth line image VR4 is displayed below the third line image VR3. However, since the video area below the third line image VR3 is stretched to make the third line image VR3 straight, it will be distorted in a form that is pulled downward. For this reason, the fourth line image VR4 does not become straight and becomes a line image that is curved and protrudes downward.

[0020] The screen V1 shown in FIG. 3 is a suitable video when it is desired to detect the third line RL3. However, in a traffic situation, it is required to accurately grasp and respond to obstacles, especially moving objects. Since the object OB shown in FIG. 2 is located near the first line RL1, when the position of the third line image VR3 is corrected to be horizontal on the screen V1, as shown by the dashed line in FIG. 3, the object image VOB will be displayed with a large curvature. Furthermore, since the object image VOB will move along the first line image VR1, it will be observed as if it is turning. For this reason, it becomes difficult to calculate the movement of the object OB from the object image VOB.

[0021] Therefore, when an object exists around the vehicle 2, the controller 12 corrects the distortion of the wide-angle video so that the position of the object in the wide-angle video (the position of the object image VOB) is horizontal on the screen of the display device 13. As a result, as shown in the screen V2 of FIG. 4, the first line image VR1 becomes straight on the screen V2, and the object image VOB is also displayed without distortion. Thus, since the movement of the object image VOB and the object OB is the same, the movement of the object OB can be calculated from the object image VOB.

[0022] [Operation of Video Display Device] FIG. 5 is a flowchart showing the operation of the video display device. The flowchart shown in FIG. 5 is executed by the video display device 1 at, for example, the timing when a driver operation is received.

[0023] As shown in FIG. 5, first, the camera in the video display device 1 captures a two-dimensional wide-angle image as step S10. Subsequently, the controller 12 of the video display device 1 determines whether an object OB exists around the vehicle 2 as step S12. The controller 12 may determine the presence of the object OB based on, for example, the detection result of the distance measuring sensor 11.

[0024] When it is determined that the object OB exists (step S12: YES), the controller 12 measures the distance to the object OB in the real space based on the detection result of the distance measuring sensor 11 as step S14.

[0025] Subsequently, the controller 12 calculates the position of the object OB in the two-dimensional wide-angle image as step S16. The controller 12 calculates the position of the object OB based on the detection result of the distance measuring sensor 11. Subsequently, the controller 12 corrects the distortion of the wide-angle video so that the position of the object in the wide-angle video (the position of the object image VOB) is horizontal on the screen of the display device 13 (see FIG. 4 for example) as step S18.

[0026] In step S12, when it is determined that the object OB does not exist (step S12: NO), the controller 12 corrects the distortion of the wide-angle video so that a predetermined position in the wide-angle video becomes horizontal on the screen of the display device 13 as step S20 (see FIG. 3 for example).

[0027] When step S18 or step S20 ends, the flowchart shown in FIG. 5 ends. When the flowchart shown in FIG. 5 ends, if the end conditions such as receiving a driver operation for the end of processing are not satisfied, the video display device 1 repeats the flowchart shown in FIG. 5 from the beginning.

[0028] [Summary of Embodiment] In the video display device 1, the position of the object in the wide-angle video captured by the camera 10 is calculated, and the distortion of the wide-angle video is corrected so that the calculated position of the object in the wide-angle video becomes horizontal on the screen of the display device 13. Thereby, the video display device 1 can alleviate the distortion of the object to be noted, and thus can display the object appropriately.

[0029] Although the exemplary embodiments have been described above, the present invention is not limited to the above-described exemplary embodiments, and various omissions, substitutions, and changes may be made. [Description of Reference Numerals]

[0030] 1... Video display device, 2... Vehicle, 10... Camera, 11... Distance measurement sensor, 12... Controller, 13... Display device.

Claims

1. A camera having a wide-angle lens for imaging a two-dimensional wide-angle image around a vehicle, A sensor for measuring the distance to an object in the real space around the vehicle, A controller connected to the camera and the sensor, A display device for displaying an image based on a signal output from the controller, comprising: The controller: calculates the position of the object in the wide-angle image captured by the camera based on the distance to the object in the real space measured by the sensor, corrects the distortion of the wide-angle image so that the position of the object in the calculated wide-angle image is horizontal on the screen of the display device. An image display device configured as such.

2. The controller: determines whether or not the object exists around the vehicle, When the object does not exist around the vehicle, corrects the distortion of the wide-angle image so that a predetermined position in the wide-angle image is horizontal on the screen of the display device. The image display device according to Claim 1.

Images