Vehicle image display system, vehicle image display method, and program

Abstract

To provide a vehicular image display system, a vehicular image display method, and a program, which limits a person from feeling glaring when looking at a display device displaying a digital image generated by an imaging device in a case where bright light enters the imaging device, while preventing the digital image from unnecessarily losing its luminosity.SOLUTION: An apparatus includes: a display device for displaying a digital image being an image based on image data; a darkness condition determination part for determining whether a darkness condition is established in relation to brightness of a surrounding environment of a vehicle; a brightness determination part for determining whether the image data contains a high-brightness pixel that is a pixel of brightness being a first threshold or higher; a pixel value determination part for determining whether a surrounding pixel being a pixel existing in a surrounding area of the high brightness pixel contains a pixel of which a pixel value equaling a second threshold or less; and an image adjustment part for performing first luminosity adjustment processing to lower luminosity of the image data in a case where the darkness condition is established, with the image data containing a high brightness pixel, and the surrounding pixel not containing a pixel of which a pixel value equaling the second threshold or less.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a vehicle image display system, a vehicle image display method, and a program. [Background technology]

[0002] In Patent Document 1 below, when the luminance value of a portion of image data (captured image) acquired by a camera is equal to or greater than a predetermined value, image processing is performed to reduce the brightness of that portion. In this case, the luminance value of the remaining portion of the image data excluding that portion is less than the predetermined value. In Patent Document 1 below, image processing is performed to adjust the exposure time and amount of light received for the image data based on luminance information of the remaining portion. Furthermore, in Patent Document 1 below, a display device displays image data that has been subjected to such image processing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-035162 Summary of the Invention [Problem to be solved by the invention]

[0004] Here, let us consider a case where the predetermined value is set to a large value. In this case, when light emitted from the lighting device of another vehicle directly hits the camera at night, the brightness of the image data is not reduced. As a result, an image based on the image data displayed on the display device may become white-out, which may cause the driver to feel dazzled when looking at the display device. On the other hand, if the predetermined value is set to a small value, the brightness of image data representing white subjects such as white lines on the road may be reduced more than necessary.

[0005] In consideration of the above, the present invention aims to provide a vehicle image display system, a vehicle image display method, and a program that make it difficult for a person viewing a display device that displays a digital image generated by a photographing device to feel dazzled when strong light enters the photographing device, and that does not reduce the brightness of the digital image more than necessary. [Means for solving the problem]

[0006] The vehicle image display system of claim 1 includes a photographing device that photographs a subject located around the vehicle, a display device that displays a digital image based on image data generated by the photographing device, a dark condition determination unit that determines whether a dark condition is met regarding the brightness of the environment around the vehicle, a brightness determination unit that determines whether the image data includes a high-brightness pixel that is a pixel with a brightness equal to or greater than a first threshold, a pixel value determination unit that determines whether surrounding pixels that are pixels around the high-brightness pixel include no pixels with a pixel value equal to or less than a second threshold, and an image adjustment unit that performs a first brightness adjustment process to reduce the brightness of the image data when a processing condition is met that is met when the dark condition is met, the image data includes the high-brightness pixel, and the surrounding pixels do not include pixels with a pixel value equal to or less than the second threshold. wherein the dark condition is met when the average luminance of the image data is equal to or less than a third threshold or the illuminance around the vehicle is equal to or less than a fourth threshold. .

[0007] In the vehicle image display system described in claim 1, the processing condition is met when the dark condition determination unit determines that the dark condition is met, the brightness determination unit determines that the image data includes a high-brightness pixel, which is a pixel with a brightness equal to or greater than a first threshold, and the pixel value determination unit determines that the surrounding pixels, which are pixels around the high-brightness pixel, do not include pixels with a pixel value equal to or less than a second threshold. Furthermore, when the processing condition is met, the image adjustment unit performs a first brightness adjustment process to reduce the brightness of the image data. In this case, if the image data includes a high-brightness pixel due to strong light entering the imaging device and the surrounding pixels do not include pixels with a pixel value equal to or less than the second threshold, there is a risk of so-called white blur occurring in the surrounding pixels. Therefore, in this case, the first brightness adjustment process is performed to reduce the brightness of the image data. Therefore, when strong light enters the imaging device, a viewer viewing a display device displaying a digital image based on the image data is less likely to experience glare.

[0008] If the dark condition is not met, if the image data does not contain high-brightness pixels, or if the surrounding pixels contain pixels with pixel values ​​equal to or lower than the second threshold, it is highly likely that white blur does not occur in the digital image based on the surrounding pixels. Therefore, the vehicular image display system described in claim 1 does not perform the first brightness adjustment process on the image data in this case. Therefore, the vehicular image display system described in claim 1 does not reduce the brightness of the image data more than necessary in such cases.

[0009] In the vehicle image display system according to claim 2, when the dark condition is met and the processing condition is not met, the image adjustment unit performs a second brightness adjustment process on the image data, which is different from the first brightness adjustment process. a difference between the brightness of the pixel of the image data before and after the second brightness adjustment process is performed is smaller than a difference between the brightness of the pixel of the image data before and after the first brightness adjustment process is performed. 2. The vehicle image display system according to claim 1.

[0010] In the vehicle image display system of claim 2, when the dark condition is met but the processing condition is not met, the image adjustment unit executes a second brightness adjustment process different from the first brightness adjustment process on the image data. Therefore, when the processing condition is not met, the vehicle image display system of claim 2 can adjust the brightness of the image data so that the vehicle occupant can easily view the digital image displayed on the display device.

[0013] Claim 3 The vehicle image display method described in the above includes a step of determining whether a dark condition is met with respect to the brightness of the environment surrounding the vehicle, a step of determining whether image data generated by an image capture device that captures an image of a subject located around the vehicle includes high-luminance pixels that are pixels with a brightness equal to or greater than a first threshold, a step of determining whether surrounding pixels that are pixels around the high-luminance pixels include pixels with a pixel value equal to or less than a second threshold, a step of performing a first brightness adjustment process to reduce the brightness of the image data when the dark condition is met, the image data includes the high-luminance pixels, and the surrounding pixels do not include pixels with a pixel value equal to or less than the second threshold, and a step of displaying a digital image that is an image based on the image data that has been subjected to the first brightness adjustment process. and the dark condition is met when the average luminance of the image data is equal to or less than a third threshold or the illuminance around the vehicle is equal to or less than a fourth threshold. .

[0014] Claim 4 the program described in the item (ii) executes on a computer the following processes: determining whether a dark condition is met with respect to the brightness of the environment surrounding the vehicle; determining whether image data generated by an image capture device that captures an image of a subject located around the vehicle includes high-luminance pixels that are pixels with a brightness equal to or greater than a first threshold; determining whether surrounding pixels that are pixels around the high-luminance pixels include pixels with a pixel value equal to or less than a second threshold; performing a first brightness adjustment process to reduce the brightness of the image data when the dark condition is met, the image data includes the high-luminance pixel, and the surrounding pixels do not include pixels with a pixel value equal to or less than the second threshold; and displaying a digital image that is an image based on the image data that has been subjected to the first brightness adjustment process. the dark condition is met when the average luminance of the image data is equal to or less than a third threshold or the illuminance around the vehicle is equal to or less than a fourth threshold. . [Effects of the Invention]

[0015] As described above, the vehicle image display system, vehicle image display method, and program according to the present invention have the excellent effect of making it difficult for a person viewing a display device that displays a digital image generated by a photographing device to feel dazzled when strong light enters the photographing device, and of not reducing the brightness of the digital image more than necessary. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a side view of a vehicle equipped with an image display system for a vehicle according to an embodiment and a following vehicle. [Figure 2] FIG. 2 is a control block diagram of an ECU mounted on a vehicle. [Figure 3] FIG. 2 is a functional block diagram of the ECU. [Figure 4] 10 is a flowchart showing processing executed by a CPU. [Figure 5] FIG. 10 is a diagram showing a rearview mirror display device displaying a digital image in which white blur occurs. [Figure 6] FIG. 10 is a diagram showing a rearview mirror display device displaying a digital image without white blur. DETAILED DESCRIPTION OF THE INVENTION

[0017] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vehicle image display system, a vehicle image display method, and a program according to the present invention will be described below with reference to the accompanying drawings.

[0018] A vehicle 10 shown in Fig. 1 is equipped with a vehicle image display system 25 (hereinafter referred to as system 25). The vehicle 10 has a vehicle body 11, a camera (photographing device) 14, a rearview mirror 16, and an ECU 20. The vehicle 10 is capable of executing driving assistance control at automated driving levels 1 to 5 defined by the Society of Automotive Engineers (SAE). Furthermore, the brightness adjustment process described below can be executed while the vehicle 10 is executing driving assistance control and while the vehicle is manually driven.

[0019] A camera 14 is provided at the rear of the vehicle body 11. The camera 14 includes an imaging element and a lens (both not shown). The imaging element includes a pixel array having a large number of pixels (dots). Each pixel outputs light incident on the pixel array through the lens as an electrical signal. The imaging element also includes an exposure adjustment system (electronic shutter).

[0020] The camera 14 is capable of capturing an image of a subject located behind the vehicle 10. For example, as shown in Fig. 1, when the vehicle 10 is traveling forward on a road 40, the camera 14 is capable of capturing an image of a following vehicle (subject) 30 traveling forward on the road 40 behind the vehicle 10. A pair of left and right lighting devices 31 (only the left lighting device 31 is shown in Fig. 1) are provided at the front end of the following vehicle 30.

[0021] A rearview mirror 16 is provided inside the vehicle 10. A digital display device 17 is provided on the rear surface of the rearview mirror 16 to display a digital image based on image data generated by the camera 14. The display device 17 has a large number of pixels (dots).

[0022] The vehicle 10 includes an ECU (Electronic Control Unit) 20. The camera 14, the display device 17, and the ECU 20 are components of an image display system 25 for a vehicle.

[0023] 2, the hardware configuration of the ECU 20 includes a CPU (Central Processing Unit: processor) (computer) 20A, a ROM (Read Only Memory) 20B, a RAM (Random Access Memory) 20C, a storage 20D, a communication I / F (Interface) 20E, an input / output I / F 20F, and a GPU (Graphics Processing Unit) 20G. The CPU 20A, ROM 20B, RAM 20C, storage 20D, communication I / F 20E, input / output I / F 20F, and GPU 20G are connected to each other via a bus 20Z so as to be able to communicate with each other.

[0024] The CPU 20A is a central processing unit that executes various programs and controls each component. That is, the CPU 20A reads programs from the ROM 20B or the storage 20D and executes the programs using the RAM 20C as a work area. The CPU 20A controls each component and performs various types of arithmetic processing (information processing) in accordance with the programs recorded in the ROM 20B or the storage 20D.

[0025] The ROM 20B stores various programs and various data. The RAM 20C temporarily stores programs or data as a working area. The storage 20D is composed of a storage device such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive) and stores various programs and various data. The communication I / F 20E is an interface for the ECU 20 to communicate with other devices. The input / output I / F 20F is an interface for communicating with various devices. For example, the camera 14 and the display device 17 are connected to the input / output I / F 20F.

[0026] The GPU 20G is a computing device for image processing. The GPU 20G reads a program from the ROM 20B or the storage 20D and executes the program using the RAM 20C as a work area.

[0027] 3 shows a functional block diagram of the ECU 20. The ECU 20 has, as its functional configuration, a brightness determination unit 201, a pixel value determination unit 202, an average brightness determination unit (dark condition determination unit) 203, a camera control unit (image adjustment unit) 204, and a display device control unit 205. These are realized by the CPU 20A and the GPU 20G reading and executing programs stored in the ROM 20B.

[0028] The brightness determination unit 201 measures the brightness of all pixels included in the image data received from the camera 14, and determines whether or not these pixels include high-brightness pixels, which are pixels with brightness equal to or greater than a first threshold value. The first threshold value is, for example, the maximum brightness value (255).

[0029] The pixel value determination unit 202 measures the pixel values ​​of all pixels included in the image data received from the camera 14, and determines whether or not any of these pixels has a pixel value equal to or less than a second threshold. When a pixel with a pixel value equal to or less than the second threshold is displayed on the display device 17, a passenger looking at the display device 17 will recognize the image represented by this pixel as black.

[0030] The average brightness determination unit 203 measures the average brightness of all pixels included in the image data received from the camera 14, and determines whether the average brightness is equal to or less than a third threshold value.

[0031] The camera control unit 204 has a brightness adjustment function. That is, the camera control unit 204 can execute brightness adjustment processing to adjust the brightness of all pixels included in the image data by controlling the camera 14. This brightness adjustment processing includes a first brightness adjustment processing, a second brightness adjustment processing, and a third brightness adjustment processing, which will be described later. The camera control unit 204 adjusts the brightness of the entire image data (all pixels) based on the average brightness value of all pixels included in the image data. More specifically, the camera control unit 204 executes the brightness adjustment processing by at least one of exposure adjustment and gain adjustment. The camera control unit 204 calculates an exposure time based on the average brightness value and controls the exposure adjustment system (electronic shutter) of the camera 14 based on the calculated exposure time information. The camera control unit 204 adjusts the amplification factor (gain) of the electrical signals output by all pixels (dots) of the image sensor based on the average brightness value.

[0032] The display device control unit 205 outputs the image data whose brightness has been adjusted to the display device 17, and causes the display device 17 to display a digital image based on the image data.

[0033] Next, the flow of processing performed by the ECU 20 will be explained using the flowchart in Fig. 4. As shown in Fig. 1, it is assumed that the vehicle 10 and the following vehicle 30 are traveling forward on the road 40 and that the lighting device 31 of the following vehicle 30 is emitting illumination light 32 forward. Furthermore, as shown in Fig. 5 and Fig. 6, it is assumed that the camera 14 is photographing the following vehicle 30 and that a digital image of the following vehicle 30 is being displayed on the display device 17 of the rearview mirror 16. It is noted that the reference numeral 41 in Fig. 5 and Fig. 6 denotes white lines indicating the edges of the road 40 on both sides.

[0034] First, in step S10 (hereinafter, the word "step" will be omitted), ECU 20 (average brightness determination unit 203) measures the average brightness of all pixels contained in the image data received from camera 14, and determines whether the average brightness is less than or equal to a third threshold value.

[0035] If S10 returns Yes, it is highly likely that the environment surrounding the vehicle 10 is dark. For example, it is highly likely that the vehicle 10 is traveling on the road 40 at night. If S10 returns Yes, a predetermined dark condition is met. On the other hand, if S10 returns No, it is highly likely that the environment surrounding the vehicle 10 is bright. For example, it is highly likely that the vehicle 10 is traveling on the road 40 during the day.

[0036] If the determination in S10 is Yes, the ECU 20 proceeds to S11 and determines whether or not all pixels included in the image data received from the camera 14 include high-luminance pixels, which are pixels with luminance equal to or greater than a first threshold value.

[0037] 5 shows the display device 17 when the distance between the vehicle 10 and the following vehicle 30 is short. At this time, a large amount of light beam contained in the illumination light 32 emitted from the lighting device 31 of the following vehicle 30 is received by the camera 14 (image sensor). That is, strong light is entering the camera 14 (image sensor). In such a case, the ECU 20 determines that the image data received from the camera 14 contains high-brightness pixels. The pixels in the image data representing at least a part of the lighting device 31 are high-brightness pixels.

[0038] 6 shows the display device 17 when the distance between the vehicle 10 and the following vehicle 30 is long. At this time, a small amount of light beam contained in the illumination light 32 emitted from the lighting device 31 of the following vehicle 30 is received by the camera 14 (image sensor). In other words, no strong light is entering the camera 14 (image sensor). In this case, the ECU 20 determines that the image data received from the camera 14 does not contain any high-brightness pixels.

[0039] If the determination in S11 is Yes, the ECU 20 proceeds to S12, where it measures the pixel values ​​of all pixels included in the image data received from the camera 14 and determines whether or not the surrounding pixels, which are pixels surrounding the high-brightness pixels, include any pixels with pixel values ​​equal to or less than a second threshold. The range of surrounding pixels may be, for example, a predetermined multiple of the range of high-brightness pixels. The range of surrounding pixels may also be a range that includes the entire object having a light source (in this embodiment, the following vehicle 30).

[0040] If S12 returns "Yes," the predetermined processing condition is met. If S12 returns "Yes" and the first brightness adjustment process is not performed, there is a high possibility that so-called white blur will occur in the digital image displayed on the display device 17. Image data (pixels) generated by specific pixels, which are some pixels (dots) included in the pixel array of the image sensor and exposed to strong light, are high-brightness pixels. In this case, light that cannot be absorbed by the specific pixels (dots) is absorbed by peripheral pixels, which are pixels (dots) surrounding the specific pixels. Therefore, if the first brightness adjustment process is not performed, the occupant will perceive the digital image based on the peripheral pixels (pixels) generated by the peripheral pixels (dots) of the image sensor as white blur.

[0041] On the other hand, if the peripheral pixels of the image data include pixels with pixel values ​​equal to or less than the second threshold, the ECU 20 determines No in S12. In this case, it is unlikely that white blur occurs in the digital image displayed on the display device 17.

[0042] If the determination in S12 is Yes, the ECU 20 proceeds to S13 and executes a first brightness adjustment process to reduce the brightness of all pixels in the image data. That is, the ECU 20 executes at least one of exposure adjustment and gain adjustment based on the average brightness of all pixels acquired in S10.

[0043] Here, the brightness of a pixel in the image data before the brightness adjustment process is performed is referred to as the initial brightness BR1, and the brightness after the brightness adjustment process is performed is referred to as the corrected brightness BR2. Furthermore, the difference between the initial brightness BR1 and the corrected brightness BR2 is referred to as the brightness reduction amount BRA (= initial brightness BR1 - corrected brightness BR2).

[0044] Furthermore, if the determination in S11 or S12 is No, the ECU 20 proceeds to S14 and executes a second brightness adjustment process to adjust the brightness of all pixels of the image data based on the average brightness of all pixels acquired in S10. The second brightness adjustment process adjusts the brightness of the image data so that the digital image displayed on the display device 17 is less likely to be blurred and is easier for the occupants of the vehicle 10 to view when the surrounding environment of the vehicle 10 is dark. Note that the brightness reduction amount BRA when the brightness of the image data is reduced by the second brightness adjustment process is smaller than when the first brightness adjustment process is executed. In other words, the second brightness adjustment process does not unnecessarily reduce the brightness of the image data that forms the basis of the digital image representing, for example, the white line 41 shown in FIG. 6. Therefore, the occupant looking at the display device 17 shown in FIG. 6 can clearly view the white line 41.

[0045] If the determination in S10 is No, the ECU 20 proceeds to S15 and executes a third brightness adjustment process that adjusts the brightness of all pixels of the image data based on the average brightness of all pixels acquired in S10. The third brightness adjustment process is a process that adjusts the brightness of the image data so that the digital image displayed on the display device 17 is easily visible to the occupants of the vehicle 10 when the environment around the vehicle 10 is bright. Therefore, the brightness of the image data is not reduced in the third brightness adjustment process.

[0046] When the processes of S13 to S15 are completed, the ECU 20 proceeds to S16 and transmits the image data that has been subjected to the brightness adjustment process to the display device 17. As a result, the display device 17 displays a digital image based on the image data that has been subjected to the brightness adjustment process.

[0047] When the process of S16 is completed, the ECU 20 temporarily ends the process of the flowchart of FIG.

[0048] As described above, the system 25 of this embodiment determines that the predetermined processing condition is met when the dark condition is met, the image data includes high-luminance pixels with a luminance equal to or greater than the first threshold, and the surrounding pixels do not include pixels with a pixel value equal to or less than the second threshold. That is, the system 25 determines whether or not there is a high likelihood of white blurring occurring in the digital image displayed on the display device 17 based on whether or not the image data includes pixels with a pixel value equal to or less than the second threshold. When this determination is made based on pixel values, it is possible to determine with high accuracy whether or not there is a high likelihood of white blurring occurring in the digital image displayed on the display device 17. Furthermore, when the processing condition is met, the system 25 performs a first brightness adjustment process on the image data to suppress the occurrence of white blurring. Therefore, a viewer viewing the display device 17 displaying a digital image based on image data that has been subjected to the first brightness adjustment process is less likely to experience glare.

[0049] On the other hand, if the dark condition is not met, if the image data does not contain high-brightness pixels, or if the surrounding pixels contain pixels with pixel values ​​equal to or lower than the second threshold, it is considered that there is a low possibility that white blur will occur in the surrounding pixels. Therefore, the system 25 does not perform the first brightness adjustment process on the image data in this case. In other words, when the processing condition is not met, the system 25 does not reduce the brightness of the image data more than necessary.

[0050] Furthermore, when the image data does not contain any high-brightness pixels or when the surrounding pixels contain pixels with pixel values ​​equal to or less than the second threshold, the system 25 executes a second brightness adjustment process that is different from the first brightness adjustment process. That is, in this case, the system 25 adjusts the brightness of the image data so that the occupants of the vehicle 10 can easily view the digital image displayed on the display device 17.

[0051] Furthermore, the system 25 determines that a dark condition exists when the average luminance of the image data is equal to or less than a third threshold. Therefore, the system 25 can accurately determine whether the environment around the vehicle 10 is dark. Therefore, the system 25 can accurately determine whether white blurring is likely to occur on the display device 17.

[0052] The above describes the vehicle image display system, vehicle image display method, and program according to the embodiment, but the design of the vehicle image display system, vehicle image display method, and program can be modified as appropriate within the scope that does not deviate from the gist of the present invention.

[0053] For example, the vehicle 10 may be provided with an illuminance detection device that detects the illuminance around the vehicle 10, and the ECU 20 may determine that the dark condition is met when the detected illuminance is equal to or less than the fourth threshold value.

[0054] The camera 14 may be provided with a variable iris device facing the imaging element. In this case, the ECU 20 may perform brightness adjustment processing by adjusting the iris diameter of the variable iris device.

[0055] The ECU 20 may perform the brightness adjustment process by performing image processing on the image data.

[0056] The display device 17 may be a display device provided on the instrument panel of the vehicle 10.

[0057] The camera 14 may be a camera that can capture an image of a subject located in a direction other than the rear of the vehicle 10.

[0058] The vehicle 10 may be equipped with a detection device capable of detecting another vehicle located around the vehicle 10 and detecting the distance between the vehicle 10 and the other vehicle. If the other vehicle is not detected or if the distance between the vehicle 10 and the other vehicle is equal to or greater than a predetermined value, the ECU 20 may determine that there is a low possibility of white blur occurring.

[0059] [Note] The vehicle image display system of the present invention may be any combination of the following configurations 1 to 5. <Configuration 1> An image display system for a vehicle, comprising: an imaging device that captures images of subjects located around a vehicle; a display device that displays digital images that are images based on image data generated by the imaging device; a dark condition determination unit that determines whether a dark condition is met with respect to the brightness of the environment around the vehicle; a brightness determination unit that determines whether the image data includes a high-brightness pixel that is a pixel with a brightness equal to or greater than a first threshold; a pixel value determination unit that determines whether surrounding pixels that are pixels around the high-brightness pixel include no pixels with a pixel value equal to or less than a second threshold; and an image adjustment unit that performs a first brightness adjustment process to reduce the brightness of the image data when a processing condition is met that is met when the dark condition is met, the image data includes the high-brightness pixel, and the surrounding pixels do not include pixels with a pixel value equal to or less than the second threshold. <Configuration 2> An image display system for a vehicle, wherein when the dark condition is met and the processing condition is not met, the image adjustment unit executes a second brightness adjustment process on the image data, which is different from the first brightness adjustment process. <Configuration 3> An image display system for a vehicle, wherein the dark condition is met when the average luminance of the image data is equal to or less than a third threshold or when the illuminance around the vehicle is equal to or less than a fourth threshold. Furthermore, the image display method for a vehicle of the present invention may be a combination of the following configuration 4 and at least one of configurations 1 to 3. <Configuration 4> The method includes a step of determining whether a dark condition is met regarding the brightness of the environment surrounding the vehicle, a step of determining whether image data generated by an imaging device that images subjects located around the vehicle includes high-brightness pixels that are pixels with a brightness equal to or greater than a first threshold, a step of determining whether surrounding pixels that are pixels around the high-brightness pixels include no pixels with pixel values ​​equal to or less than a second threshold, a step of performing a first brightness adjustment process to reduce the brightness of the image data when a processing condition is met that is met when the dark condition is met, the image data includes the high-brightness pixels, and the surrounding pixels do not include pixels with pixel values ​​equal to or less than the second threshold, and a step of displaying a digital image that is an image based on the image data that has been subjected to the first brightness adjustment process. Furthermore, the program of the present invention may be a combination of the following configuration 5 and at least one of configurations 1 to 3. <Configuration 5> A computer is caused to execute a process of determining whether a dark condition is met regarding the brightness of the environment surrounding the vehicle, a process of determining whether image data generated by an imaging device that photographs subjects located around the vehicle includes high-brightness pixels that are pixels with a brightness equal to or greater than a first threshold, a process of determining whether surrounding pixels that are pixels around the high-brightness pixels include no pixels with pixel values ​​equal to or less than a second threshold, a process of performing a first brightness adjustment process to reduce the brightness of the image data when a processing condition is met that is met when the dark condition is met, the image data includes the high-brightness pixels, and the surrounding pixels do not include pixels with pixel values ​​equal to or less than the second threshold, and a process of displaying a digital image that is an image based on the image data that has been subjected to the first brightness adjustment process. [Explanation of symbols]

[0060] 10 vehicles 14 Camera (photographic device) 17 Display device 201 Luminance determination unit 202 Pixel value determination unit 203 Average brightness determination unit (dark condition determination unit) 204 Camera control unit (image adjustment unit) 25 Vehicle image display system 30 Following vehicle (subject)

Claims

1. an imaging device that captures images of subjects located around the vehicle; a display device that displays a digital image based on the image data generated by the imaging device; a dark condition determination unit that determines whether a dark condition is met with respect to the brightness of the surrounding environment of the vehicle; a brightness determination unit that determines whether the image data includes high-brightness pixels that are pixels with brightness equal to or greater than a first threshold; a pixel value determination unit that determines whether or not a pixel with a pixel value equal to or less than a second threshold value is included in the surrounding pixels that are pixels surrounding the high-luminance pixel; an image adjustment unit that performs a first brightness adjustment process to reduce brightness of the image data when a processing condition is satisfied that is satisfied when the dark condition is satisfied, the image data includes the high-brightness pixel, and the peripheral pixels do not include pixels with pixel values ​​equal to or less than the second threshold; Equipped with The dark condition is met when the average luminance of the image data is equal to or less than a third threshold or when the illuminance around the vehicle is equal to or less than a fourth threshold.

2. When the dark condition is met and the processing condition is not met, the image adjustment unit executes a second brightness adjustment process on the image data, the second brightness adjustment process being different from the first brightness adjustment process; 2. The vehicle image display system according to claim 1, wherein the difference between the brightness of the pixel of the image data before the second brightness adjustment process is performed and the brightness after the second brightness adjustment process is performed is smaller than the difference between the brightness of the pixel of the image data before the first brightness adjustment process is performed and the brightness after the second brightness adjustment process is performed.

3. determining whether a dark condition exists with respect to the brightness of the surrounding environment of the vehicle; a step of determining whether or not high-luminance pixels, which are pixels having luminance equal to or greater than a first threshold value, are included in image data generated by an image capturing device that captures an image of a subject located around the vehicle; a step of determining whether or not the surrounding pixels surrounding the high-luminance pixel include no pixels with pixel values ​​equal to or less than a second threshold; performing a first brightness adjustment process to reduce brightness of the image data when the dark condition is met, the image data includes the high-brightness pixel, and the peripheral pixels do not include a pixel having a pixel value equal to or less than the second threshold; and displaying a digital image based on the image data subjected to the first brightness adjustment process; and The dark condition is met when an average luminance of the image data is equal to or less than a third threshold or when an illuminance around the vehicle is equal to or less than a fourth threshold.

4. A process of determining whether a dark condition is established with respect to the brightness of the surrounding environment of the vehicle; a process of determining whether or not high-luminance pixels, which are pixels having a luminance equal to or greater than a first threshold, are included in image data generated by an image capturing device that captures an image of a subject located around the vehicle; a process of determining whether or not the surrounding pixels, which are pixels surrounding the high-luminance pixel, include a pixel with a pixel value equal to or less than a second threshold; a process of performing a first brightness adjustment process of reducing brightness of the image data when the dark condition is met, the image data includes the high-brightness pixel, and the peripheral pixels do not include a pixel having a pixel value equal to or less than the second threshold; and a process of displaying a digital image based on the image data subjected to the first brightness adjustment process; on the computer, The dark condition is established when the average luminance of the image data is equal to or less than a third threshold or the illuminance around the vehicle is equal to or less than a fourth threshold.

Images