Driving assistance system, driving assistance method, and recording medium

Abstract

In the present invention, the information that is necessary for determining, or the like, whether it is possible to avoid an obstacle that is in a path direction is made abundant.　This driving assistance system comprises: a setting unit that sets a section to be measured for measuring a passable width of a lane on the side of an obstacle on a road in an image captured by a camera capable of imaging the road; an estimation unit that estimates the passable width of the lane on the basis of the ratio of the size of the section to be measured and the size of a subject included in the image that has been set in advance; and a transmission unit that transmits driving assistance information, which is based on the passable width of the lane, to a vehicle in relation to which the obstacle is in a path direction.

Description

Driving assistance system, driving assistance method, and recording medium

[0001] The present invention relates to a driving assistance system, a driving assistance method, and a recording medium.

[0002] When traveling on a road, one of the criteria used to determine whether to take action to avoid an obstacle ahead is whether the vehicle can avoid the obstacle without crossing the center line or lane markings.

[0003] Patent Literature 1 discloses an example of a driving assistance device that can optimize obstacle avoidance operations. The driving assistance device described in this document calculates the distance to the farthest point in the area occupied by the obstacle (obstacle width) using one of the left and right sides of the driving lane opposite the avoidance direction as a reference. The driving assistance device then determines whether to change lanes to overtake the obstacle or to avoid the obstacle without changing lanes.

[0004] JP 2018-89990 A

[0005] When a camera mounted on the vehicle is used as in Patent Document 1, the camera's installation position and angle of view are fixed, so the image can be analyzed to calculate obstacles and their widths, and the amount of protrusion can be determined with a certain degree of accuracy. However, a method using a camera mounted on the vehicle has the problem that it cannot capture obstacles outside the field of view, and therefore cannot provide information about obstacles outside the field of view.

[0006] The present disclosure aims to provide a driving assistance system, a driving assistance method, and a recording medium that can contribute to enriching information necessary for determining whether an obstacle in the path can be avoided.

[0007] According to a first aspect, there is provided a driving assistance system comprising: a setting unit that sets a measured section for measuring the passable width of a lane to the side of an obstacle on a road in an image captured by a camera capable of photographing the road; an estimation unit that estimates the passable width of the lane based on the size ratio between the measured section and a subject that appears in the image that has been set in advance; and a transmission unit that transmits driving assistance information based on the passable width of the lane to a vehicle in the direction of travel of the obstacle.

[0008] According to a second aspect, there is provided a driving assistance method that sets a measured section for measuring the passable width of a lane to the side of an obstacle on a road in an image captured by a camera capable of photographing the road, estimates the passable width of the lane based on the size ratio between the measured section and a previously set subject that appears in the image, and transmits driving assistance information based on the passable width of the lane to a vehicle in the direction of travel of the obstacle.

[0009] According to a third aspect, there is provided a recording medium storing a program that causes a computer to execute the following processes: a process of setting a measured section for measuring the passable width of a lane to the side of an obstacle on a road in an image captured by a camera capable of photographing the road; a process of estimating the passable width of the lane based on the size ratio between the measured section and a previously set subject that appears in the image; and a process of transmitting driving assistance information based on the passable width of the lane to a vehicle in the direction of travel of the obstacle.

[0010] The present disclosure can contribute to enriching the information required to determine whether an obstacle in the path can be avoided.

[0011] FIG. 1 is a diagram showing one configuration of the present disclosure. FIG. 2 is a flowchart showing the operation of the present disclosure. FIG. 3 is a diagram for explaining the passable width estimated by the present disclosure. FIG. 4 is another diagram for explaining the passable width estimated by the present disclosure. FIG. 1 is a diagram showing one configuration of the present disclosure. FIG. 2 is a flowchart showing the operation of the present disclosure. FIG. 3 is a diagram showing an example of a suitable positional relationship between a camera and a vehicle in the present disclosure. FIG. 4 is another diagram showing an example of a suitable positional relationship between a camera and a vehicle in the present disclosure. FIG. 5 is a diagram showing another configuration of the present disclosure. FIG. 6 is another diagram for explaining the passable width estimated by the present disclosure. FIG. 7 is a diagram showing the configuration of a computer constituting an information processing device of the present disclosure.

[0012] First, an overview of one embodiment of the present disclosure will be described with reference to the drawings. In this disclosure, the drawings relate to one or more embodiments. The reference numerals in the drawings attached to this overview are attached to each element for convenience as an example to facilitate understanding, and are not intended to limit the present disclosure to the illustrated form. Furthermore, connecting lines between blocks in the drawings and the like referred to in the following description include both bidirectional and unidirectional lines. Unidirectional arrows are used to schematically indicate the flow of main signals (data) and do not exclude bidirectionality. A program is executed via a computer device, which includes, for example, a processor, a storage device, an input device, a communication interface, and, if necessary, a display device. Furthermore, this computer device is configured to be able to communicate with internal or external devices (including computers) via the communication interface, whether wired or wireless. Although ports or interfaces are present at the input / output connection points of each block in the drawings, they are not shown.

[0013] 1 , the present disclosure can be realized in a driving assistance system 10 including a setting unit 11, an estimation unit 12, and a transmission unit 13. More specifically, the setting unit 11 sets a measurement section w11 for measuring the passable width of a lane located to the side of an obstacle (e.g., a vehicle V) on a road in an image captured by a camera C capable of capturing an image of the road.

[0014] The estimation unit 12 estimates the passable width of the lane based on the ratio of the size of the measured section w11 to a predetermined object (center line in FIG. 1 ) that appears in the image. Specifically, the estimation unit 12 estimates the measured section w11 based on the ratio of the measured section w11 to the width w12 of the center line. Here, the width w12 of the center line is assumed to be known.

[0015] The transmitter 13 transmits driving assistance information based on the passable width of the lane to a vehicle in the direction of travel of the obstacle. The driving assistance information can be transmitted to a second vehicle via a mobile communication network or road-to-vehicle communication.

[0016] The driving assistance system 10 configured as described above operates as follows. First, the driving assistance system 10 sets a measurement section to measure the passable width of the lane to the side of an obstacle on the road in the image captured by the camera C (step S01 in FIG. 2). For example, the driving assistance system 10 sets a measurement section w11 to measure the passable width of the lane to the side of the truck in the camera image of FIG. 3. As an example, the measurement section w11 can be set to the section between the side of the obstacle on the center line side and the center line.

[0017] Next, the driving assistance system 10 estimates the passable width of the lane based on the ratio of the size of the measured section w11 to a predetermined object captured in the image (step S02 in FIG. 2). For example, if the object is a center line, the driving assistance system 10 estimates the passable width of the lane using the number of pixels of the measured section w11 in the image and the number of pixels of the width w12 of the center line. Note that if the obstacle is a vehicle, the driving assistance system 10 may calculate the passable width to be narrower by the width of the vehicle's mirror.

[0018] Finally, the driving assistance system 10 transmits driving assistance information based on the passable width of the lane to a vehicle located in front of the obstacle (step S03 in FIG. 2). For example, if a value such as 2 m is obtained as the passable width, the driving assistance system 10 uses this 2 m as is or processes the value to create driving assistance information and transmits it to a vehicle that is traveling in the direction of the obstacle.

[0019] By using the driving assistance system 10 that operates as described above, it becomes possible for a vehicle heading toward an obstacle to appropriately determine whether to overtake the obstacle that is out of its field of view, or to take measures such as slowing down or stopping without overtaking the obstacle. This is because a configuration is adopted in which a subject of known size is used to measure a section of interest.

[0020] In addition to road dividing lines, road markings painted on the road can also be suitably used as the subject. In this case, it is desirable that the "measured section" and the "subject" are located at approximately the same distance from camera C. This simplifies the calculation of the size ratio between the "measured section" and the "subject."

[0021] In the example of Figure 3, the passable width of the measured section w11 is the same as that of the measured section w11, but the passable width may be different from that of the measured section w11. For example, as shown in Figure 4, the passable width plus a certain margin width w13 may be defined as the measured section w11. In this case, the driving assistance system 10 estimates the passable width as the distance obtained by subtracting the margin width w13 from the measured section w11. This makes it possible to provide driving assistance information with values ​​adjusted to be safer to a vehicle heading toward an obstacle.

[0022] Depending on the road, the obstacle may be a lane divider in the center of the road or a vehicle parked in a zebra strip. In this case, the section between the side of the obstacle facing the shoulder strip and the shoulder strip can be set as the measurement section.

[0023] [First embodiment] Next, a first embodiment in which driving assistance information is transmitted to a vehicle that is a service target will be described. Fig. 5 is a diagram showing one configuration of the present disclosure. Referring to Fig. 5, a configuration including a driving assistance system 100 and a camera C connected to this driving assistance system 100 is shown.

[0024] The driving assistance system 100 includes a vehicle extraction unit 101 , a selection unit 102 , a measured section setting unit 103 , a distance estimation unit 104 , a transmission unit 105 , and an inference model 111 .

[0025] The vehicle extraction unit 101 uses the inference model 111 to extract an image of a vehicle V from an image captured by the camera C, and sends the extraction result to the selection unit 102. The inference model 111 is trained and tuned using training data prepared in advance, and is generated so that it can detect an object (vehicle V) in an image.

[0026] The selection unit 102 selects vehicles V in the image extracted by the vehicle extraction unit 101 that meet predetermined conditions. For example, the selection unit 102 selects vehicles parked on the road or vehicles moving slowly. In this case, the predetermined conditions are set to be a vehicle that has remained in the same position for a predetermined time, a vehicle that is moving at a predetermined speed or less, or the like.

[0027] The measurement section setting unit 103 sets a measurement section for measuring the passable width of the lane on the side of the vehicle V selected by the selection unit 102. This measurement section setting unit 103 corresponds to the setting unit 11 described above.

[0028] The distance estimation unit 104 estimates the passable width of the lane based on the ratio of the size of the measured section to that of a previously set object of known size. Specifically, the distance estimation unit 104 estimates the length of the measured section based on the ratio of the number of pixels of the measured section in the image to the number of pixels of the object. The object can be any of various shapes painted on the road. In the following description, the distance estimation unit 104 estimates the length of the measured section using a centerline whose horizontal width (w12 in FIG. 3) is known.

[0029] The transmitting unit 105 creates driving assistance information using the length of the measured section estimated by the distance estimating unit 104 and transmits it to a second vehicle in the direction of the vehicle V's path.

[0030] Next, the operation of this embodiment will be described in detail with reference to the drawings. Fig. 6 is a diagram showing the overall operation of one configuration. Referring to Fig. 6, first, the driving assistance system 100 extracts a vehicle from an image captured by the camera C (step S001).

[0031] Next, the driving assistance system 100 determines whether the extracted vehicle is a vehicle for which a measurement section is to be set. If the extracted vehicle is not a vehicle for which a measurement section is to be set, the driving assistance system 100 skips the subsequent processing (No in step S002).

[0032] If the vehicle is not the target vehicle for setting a measured section (Yes in step S002), the driving assistance system 100 sets a measured section to measure the passable width of the lane to the side of the vehicle (step S003).

[0033] Next, the driving assistance system 100 calculates (estimates) the length of the measurement section (step S004).

[0034] Finally, the driving assistance system 100 creates driving assistance information using the estimated length of the measured section and transmits it to a second vehicle traveling in the same direction as the vehicle V.

[0035] This driving assistance information may take various forms. For example, the length of the measured section may be transmitted directly to the second vehicle. The second vehicle can then compare its own width with the passable width of the lane and determine whether it can safely overtake vehicle V.

[0036] In addition, if the width of the second vehicle is known, the driving assistance system 100 can also transmit to the second vehicle, as driving assistance information, the determination result as to whether or not the second vehicle can safely overtake vehicle V.

[0037] Furthermore, the driving assistance system 100 may transmit the driving assistance information directly to the second vehicle. However, if a server or the like that provides driving assistance information to the second vehicle exists, the driving assistance system 100 may transmit the driving assistance information to this server. This server may be a driving assistance server or an automated driving assistance server that grasps the road conditions around the vehicle V and the second vehicle and provides the information to the second vehicle. In this case, the server provides driving assistance to the second vehicle using the passable width of the lane received from the driving assistance system 100 in addition to the road conditions around the vehicle V and the second vehicle. In this way, it becomes possible to provide driving assistance that takes into account not only the passable width of the lane but also the presence of pedestrians and the like around the vehicle V and the situation of oncoming vehicles.

[0038] Next, the preferred positional relationship between the arrangement of camera C and the second vehicle in the present disclosure will be described. Fig. 7 is a diagram showing an example of the preferred positional relationship between the camera and the vehicle in the present disclosure. In the example of Fig. 7, camera C is installed at a position a predetermined distance away from the intersection so that it can capture images in the direction of the intersection. Here, for example, it is assumed that the driving assistance system 100 detects a parked vehicle V1.

[0039] In this case, the driving assistance system 100 sets a measured section w11 for measuring the passable width of the lane to the side of the parked vehicle V1. The driving assistance system 100 then transmits driving assistance information created using the length of the measured section to the second vehicle V2 waiting to turn right in the right-turn lane. In a case like that shown in FIG. 7 , the parked vehicle V1 is not within the field of view of the onboard camera of the second vehicle V2, or even if the parked vehicle V1 is within the field of view, its position makes it difficult to measure the passable width of the lane to the side. According to the present disclosure, even in such a case, it is possible to accurately measure the passable width of the lane to the side of the parked vehicle V1 and communicate this information to the second vehicle V2. The second vehicle V2 can use the driving assistance information obtained from the driving assistance system 100 to perform safer operations, such as changing the right-turn course toward the center line or waiting to turn right.

[0040] FIG. 8 is a diagram showing another example of a suitable positional relationship between a camera and a vehicle according to the present disclosure. The vehicle to which the driving assistance system 100 transmits driving assistance information may be a second vehicle V2 located behind a parked vehicle V1, as shown in FIG. 8 . In the example of FIG. 8 , a third vehicle V3 is present between the second vehicle V2 and the parked vehicle V1. Therefore, the parked vehicle V1 is difficult to see from the onboard camera of the second vehicle V2, making it difficult to measure the passable width of the lane to its side. According to the present disclosure, even in such a case, it is possible to accurately measure the passable width of the lane to the side of the parked vehicle V1 and transmit this information to the second vehicle V2. Using the driving assistance information obtained from the driving assistance system 100, the second vehicle V2 can take safer actions, such as moving closer to the center line or slowing down.

[0041] As described above, according to this embodiment, it is possible to provide a vehicle (second vehicle) in the direction of travel of the parked vehicle V1 with the passable width of the lane to the side of the parked vehicle V1 in the form of driving assistance information.

[0042] In the above embodiment, an example has been described in which the driving assistance system 100 selects the parked vehicle V1, but the driving assistance system 100 may also select a vehicle that is moving slowly. For example, by selecting a road sweeper, an autonomous vehicle, or the like and providing a passable width for the lane on the side of the vehicle, it becomes possible to assist these vehicles in passing safely.

[0043] As can be understood from the above description, the target to which the driving assistance system 100 transmits driving assistance information can be an autonomous vehicle. In this case, the autonomous vehicle can determine whether to drive to avoid the obstacle based on the driving assistance information.

[0044] Second Embodiment In the first embodiment described above, the driving assistance system 100 is described as estimating the length of the measurement section using a centerline on the road, but the shape on the road that the driving assistance system 100 uses to estimate the length of the measurement section is not limited to this. For example, as shown in Figure 9, a diamond-shaped shape on the road (a diamond mark, which in Japan is a sign indicating "pedestrian crossing or bicycle crossing ahead") can also be used to estimate the length of the measurement section to the side of the parked vehicle V1. Specifically, the length of the measurement section w11 can be estimated using the number of pixels in the measurement section w11 relative to the width w22 of a diamond-shaped shape of known size.

[0045] By using such a large-sized road figure, it is possible to further improve the accuracy of estimating the length of the measurement section.

[0046] In addition to the center line and diamond markings described above, various shapes painted on the road can be used. Suitable examples include crosswalks, zebra lines, speed signs, and signs such as "Stop." If these road shapes are standardized, the driving assistance system 100 estimates the length of the measurement section w11 using the standard dimensions. Some of these road shapes may not have standardized sizes. In this case, the driving assistance system 100 estimates the length of the measurement section w11 using the dimensions of the shapes obtained through a field survey or the like.

[0047] Furthermore, the subject captured in the image may be a vehicle traveling on a road with a known width. For example, as shown in FIG. 10 , the license plate width w12a and vehicle width w12b of a parked vehicle V11 may be known. Examples of such vehicles with known sizes include buses and transportation vehicles that regularly travel the same route. In this case, the driving assistance system 100 estimates the length of the measurement section w11 using the ratio between the number of pixels in the image and the number of pixels in the measurement section w11.

[0048] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and further modifications, substitutions, and adjustments can be made without departing from the basic technical concept of the present disclosure. For example, the network configurations, element configurations, and data representation formats shown in the drawings are examples intended to aid in understanding the present disclosure, and are not limited to the configurations shown in these drawings.

[0049] (Hardware Configuration) In each embodiment of the present disclosure, each component of each device represents a functional unit block. Some or all of the components of each device are realized by an arbitrary combination of an information processing device 900 and a program, for example, as shown in FIG. 11 . FIG. 11 is a block diagram showing an example of the hardware configuration of the information processing device 900 that realizes each component of each device. The information processing device 900 includes, as an example, the following configuration: - CPU (Central Processing Unit) 901 - ROM (Read Only Memory) 902 - RAM (Random Access Memory) 903 - Program 904 loaded into RAM 903 - Storage device 905 that stores the program 904 - Drive device 907 that reads and writes to a recording medium 906 - Communication interface 908 that connects to a communication network 909 - Input / output interface 910 that inputs and outputs data - Bus 911 that connects each component

[0050] Each component of each device in each embodiment is realized by the CPU 901 acquiring and executing a program 904 that realizes these functions. That is, the CPU 901 in FIG. 11 executes a measurement section setting program and a distance estimation program, and performs an update process for each calculation parameter stored in the RAM 903, storage device 905, etc. The program 904 that realizes the function of each component of each device is stored in the storage device 905 or ROM 902 in advance, for example, and is read by the CPU 901 as needed. The program 904 may be supplied to the CPU 901 via the communication network 909, or may be stored in advance on the recording medium 906, and the drive device 907 may read the program and supply it to the CPU 901.

[0051] There are various variations in the method of realizing each device. For example, each device may be realized by any combination of a separate information processing device 900 and a program for each component. Furthermore, multiple components included in each device may be realized by any combination of a single information processing device 900 and a program. That is, each unit (processing means, function) of the driving assistance system shown in the first and second embodiments can be realized by a computer program that causes a processor installed in the device to execute each of the above-mentioned processes using its hardware.

[0052] In addition, some or all of the components of each device may be realized by other general-purpose or dedicated circuits, processors, etc., or a combination of these. These may be configured by a single chip, or by multiple chips connected via a bus.

[0053] Some or all of the components of each device may be realized by a combination of the above-mentioned circuits and programs.

[0054] When some or all of the components of each device are realized by multiple information processing devices, circuits, etc., the multiple information processing devices, circuits, etc. may be centrally or decentralized. For example, the information processing devices, circuits, etc. may be realized as a client-server system, a cloud computing system, or the like, in a form in which each device is connected via a communication network.

[0055] It should be noted that the above-described embodiments are preferred embodiments of the present disclosure, and the scope of the present disclosure is not limited to only the above-described embodiments. In other words, those skilled in the art can modify or substitute the above-described embodiments to construct various modified forms without departing from the gist of the present disclosure.

[0056] A part or all of the above-described embodiments can be described as, but not limited to, the following supplementary notes.

[0057] [Supplementary Note 1] A driving assistance system comprising: a setting unit that sets a measurement section for measuring the passable width of a lane to the side of an obstacle on a road in an image captured by a camera capable of photographing the road; an estimation unit that estimates the passable width of the lane based on the size ratio between the measurement section and a previously set object captured in the image; and a transmission unit that transmits driving assistance information based on the passable width of the lane to a vehicle traveling in the direction of the obstacle. [Supplementary Note 2] The extraction unit of the driving assistance system described above may be configured to extract the section between the side of the obstacle on the center line side and the center line as the measurement section. [Supplementary Note 3] The driving assistance system described above may further be configured to include a selection unit that selects a parked vehicle or a vehicle moving slowly from the image captured by the camera as the obstacle. [Supplementary Note 4] The driving assistance system described above may be configured to use a figure painted on the road as the object. [Supplementary Note 5] The above-mentioned driving assistance system can be configured to use a vehicle traveling on a road or a vehicle license plate as the subject. [Supplementary Note 6] The above-mentioned driving assistance system can be configured to transmit the driving assistance information to an autonomous vehicle that determines whether to drive to avoid the obstacle based on the driving assistance information. [Supplementary Note 7] A driving assistance method comprising: setting a measured section for measuring the passable width of a lane to the side of an obstacle on the road in an image; estimating the passable width of the lane based on a size ratio between the measured section and a previously set subject appearing in the image; and transmitting driving assistance information based on the passable width of the lane to a vehicle in the path of which the obstacle is located. [Supplementary Note 8] A recording medium storing a program that causes a computer to execute the following processes: a process of setting a measurement section for measuring the passable width of a lane on the side of an obstacle on a road in an image captured by a camera capable of photographing the road; a process of estimating the passable width of the lane based on a size ratio between the measurement section and a previously set subject that appears in the image; and a process of transmitting driving assistance information based on the passable width of the lane to a vehicle in the path of which the obstacle is located.The embodiments described in the above Supplementary Notes can be combined with each other after making necessary modifications. For example, a configuration that combines the contents of Supplementary Note 2 and the contents of Supplementary Note 3 is also included in the scope of disclosure of this specification. Furthermore, the embodiments of Supplementary Notes 7 and 8 can be expanded into the embodiments of Supplementary Notes 2 to 6, just like Supplementary Note 1.

[0058] The disclosures of the above-cited patent documents are incorporated herein by reference and may be used as the basis or part of this disclosure, as necessary. Modifications and adjustments of the embodiments and examples are possible within the scope of this disclosure (including the claims), and further based on its basic technical concept. Furthermore, various combinations and selections (including partial deletions) of various disclosed elements (including elements of each claim, each element of each embodiment or example, each element of each drawing, etc.) are possible within the scope of this disclosure. In other words, this disclosure naturally includes various modifications and alterations that would be possible by a person skilled in the art in accordance with the entire disclosure, including the claims, and the technical concept. In particular, with regard to the numerical ranges described herein, any numerical value or subrange within that range should be construed as specifically described, even if not otherwise specified. Furthermore, the disclosures of the above-cited documents, when used in part or in whole in combination with the disclosures herein as part of this disclosure, in accordance with the spirit of this disclosure, are also deemed to be included in the disclosures of this application.

[0059] REFERENCE SIGNS LIST 10 Driving assistance system 11 Setting unit 12 Estimation unit 13 Transmission unit 100 Driving assistance system 101 Vehicle extraction unit 102 Selection unit 103 Measurement section setting unit 104 Distance estimation unit 105 Transmission unit 111 Inference model 900 Information processing device 901 CPU (Central Processing Unit) 902 ROM (Read Only Memory) 903 RAM (Random Access Memory) 904 Program 905 Storage device 906 Recording medium 907 Drive device 908 Communication interface 909 Communication network 910 Input / output interface 911 Bus C Camera V, V1, V2, V3 Vehicle V11 Parked vehicle w11 Measurement section w12 Width of center line w12a Width of license plate w12b Vehicle width w13 Margin width w22 Width of figure on road

Claims

1. A driving support system comprising: a setting unit configured to set a measurement section for measuring a passable width of a lane on a side of an obstacle on a road in an image captured by a camera capable of photographing the road; an estimation unit configured to estimate the passable width of the lane based on a ratio of sizes between the measurement section and a subject set in advance and included in the image; and a transmission unit configured to transmit driving support information based on the passable width of the lane to a vehicle in which the obstacle is in a traveling direction.

2. The driving support system according to claim 1, wherein the extraction unit extracts, as the measurement section, a section between a side surface on a center line side of the obstacle and the center line.

3. The driving support system according to claim 1 or 2, further comprising a selection unit configured to select, as the obstacle, a parked vehicle or a vehicle traveling at low speed from an image captured by the camera.

4. The driving support system according to any one of claims 1 to 3, wherein the subject is a figure drawn on a road with paint.

5. The driving support system according to any one of claims 1 to 4, wherein the subject is a vehicle traveling on a road or a license plate of a vehicle.

6. The driving support system according to any one of claims 1 to 5, wherein the vehicle is an autonomous vehicle configured to determine whether to perform driving to avoid the obstacle based on the driving support information.

7. A driving support method, comprising: setting a measurement section for measuring a passable width of a lane on a side of an obstacle on a road in an image; estimating the passable width of the lane based on a ratio of sizes between the measurement section and a subject set in advance and included in the image; and transmitting driving support information based on the passable width of the lane to a vehicle in which the obstacle is in a traveling direction.

8. A recording medium storing a program for causing a computer to execute: a process of setting a measurement section for measuring a passable width of a lane on a side of an obstacle on the road in an image captured by a camera capable of photographing the road; a process of estimating the passable width of the lane based on a ratio of the size of the measurement section to a subject imaged in the image set in advance; and a process of transmitting driving support information based on the passable width of the lane to a vehicle in which the obstacle is in the traveling direction.

Images