Patent Publication Number: US-2022212787-A1

Title: Image capturing system, control device, control method, and storage medium

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application is a continuation of International Patent Application No. PCT/JP2020/035124 filed on Sep. 16, 2020, which claims priority to and the benefit of Japanese Patent Application No. 2019-177692 filed on Sep. 27, 2019, the entire disclosures of which are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to an image capturing system, a control device, a control method, and a storage medium, and particularly relates to a technique for capturing an image of a subject registered in advance by an unmanned aerial vehicle. 
     Description of the Related Art 
     Japanese Patent Laid-Open No. 2017-182690 A discloses a technique for capturing an image of a plurality of moving objects using an autonomous flight robot. 
     SUMMARY OF THE INVENTION 
     Technical Problem 
     However, the technique of Japanese Patent Laid-Open No. 2017-182690 A is to capture an image of a large number of unspecified intruders or moving objects such as vehicles having intruded into a monitored space using a camera of an autonomous flight robot for the purpose of crime prevention. 
     When an image of a subject registered in advance is captured by an unmanned aerial vehicle, it may be necessary to capture an image by using information of the subject registered in advance. 
     The present invention provides a technology capable of capturing an image of a subject registered in advance by an unmanned aerial vehicle. 
     Solution to Problem 
     An image capturing system according to a first aspect of the present invention is an image capturing system including: an unmanned aerial vehicle including an image capturing unit capable of capturing an image of a subject in a flight state; and a control device capable of communicating with a terminal of the subject and the unmanned aerial vehicle, wherein 
     the control device includes: 
     a storage unit configured to register subject information in which the subject is set as a target to be captured; 
     a determination unit configured to determine whether the subject is present in a predetermined image capturing area, on the basis of location information of the subject acquired by communication with the terminal and map information; 
     a signal generation unit configured to generate a control signal that controls the image capturing unit on the basis of determination of the determination unit; and 
     a communication control unit configured to transmit the subject information and the control signal to the unmanned aerial vehicle, and 
     the unmanned aerial vehicle further includes: 
     an identification unit configured to identify the subject on the basis of subject information distributed from the terminal of the subject and the subject information transmitted from the communication control unit; and 
     an image capturing control unit configured to control the image capturing unit on the basis of the control signal to control image capturing of the subject identified by the identification unit. 
     The image capturing system according to a second aspect of the present invention, wherein the storage unit registers, as the subject information, group information in which users of a plurality of vehicles constituting the subject are set as a group of targets to be captured, and the determination unit determines, on the basis of location information of the subject and the map information, whether or not the subject is traveling in a predetermined image capturing area. 
     The image capturing system according to a third aspect of the present invention, wherein, when the determination unit determines that at least one of the plurality of vehicles set as the group has entered the image capturing area, the determination unit determines that the plurality of vehicles is traveling in the image capturing area, 
     the signal generation unit generates a control signal that instructs start of image capturing, and 
     the image capturing control unit controls the image capturing unit on the basis of the control signal to start capturing images of the group of the plurality of vehicles. 
     The image capturing system according to a fourth aspect of the present invention, wherein, when the determination unit determines that at least one of the plurality of vehicles is traveling in the image capturing area, 
     the signal generation unit generates a control signal that instructs continuation of image capturing, 
     the image capturing control unit controls the image capturing unit on the basis of the control signal to continue the image capturing, 
     when the determination unit determines that all of the plurality of vehicles have left the image capturing area, 
     the signal generation unit generates a control signal that instructs end of image capturing, and 
     the image capturing control unit controls the image capturing unit on the basis of the control signal to end the image capturing. 
     The image capturing system according to a fifth aspect of the present invention, wherein, when the determination unit determines that all of the plurality of vehicles set as the group have entered the image capturing area, the determination unit determines that the plurality of vehicles is traveling in the image capturing area, 
     the signal generation unit generates a control signal that instructs start of image capturing, and 
     the image capturing control unit controls the image capturing unit on the basis of the control signal to start capturing images of the group of the plurality of vehicles. 
     The image capturing system according to a sixth aspect of the present invention, wherein, when the determination unit determines that at least one of the plurality of vehicles has entered the image capturing area or a preparation area. that is predetermined and set before the image capturing area, 
     the signal generation unit generates an area notification signal that notifies the users that the at least one of the plurality of vehicles has entered the image capturing area or the preparation area, and 
     the communication control unit transmits the area notification signal to the plurality of vehicles. 
     The image capturing system according to a seventh aspect of the present invention, wherein the control device further includes: 
     an image processing unit configured to perform image processing of extracting faces of the users from image data captured by the image capturing unit; and 
     an image determination unit configured to determine whether or not images of the faces of the users have been captured equivalent to the number of persons set as the group on the basis of a result of the image processing and the group information, and 
     when images of the faces of the users have not been captured equivalent to the number of persons set as the group, the signal generation unit generates a parameter control signal that controls an image capturing parameter of the image capturing unit such that images of the faces of the users can be captured equivalent to the number of persons set as the group, and 
     the image capturing control unit of the unmanned aerial vehicle 
     controls the image capturing unit on the basis of the parameter control signal to perform the image capturing, 
     The image capturing system according to an eighth aspect of the present invention, wherein, when images of the faces of the users have not been captured equivalent to the number of persons set as the group in determination of the image determination unit, 
     the signal generation unit generates an image capturing guide signal that guides the users to redo the image capturing, and 
     the communication control unit transmits the image capturing guide signal to the plurality of vehicles. 
     The image capturing system according to a ninth aspect of the present invention, wherein the determination unit 
     acquires an inter-vehicle distance of the plurality of vehicles traveling in the image capturing area or a predetermined preparation area set before the image capturing area on the basis of the location information, when the determination unit determines that the inter-vehicle distance exceeds a distance of an upper limit of a predetermined reference distance range, 
     the signal generation unit 
     generates a distance notification signal that notifies the users that the inter-vehicle distance exceeds the distance of the upper limit of the reference distance range, and 
     the communication control unit transmits the distance notification signal to the plurality of vehicles. 
     The image capturing system according to a tenth aspect of the present invention, wherein the determination unit 
     acquires an inter-vehicle distance of the plurality of vehicles traveling in the image capturing area or the predetermined preparation area set before the image capturing area on the basis of the location information, when the determination unit determines that the inter-vehicle distance is equal to or less than a distance of a lower limit of a predetermined reference distance range, 
     the signal generation unit 
     generates an approach notification signal that notifies the users that the inter-vehicle distance is equal to or less than the distance of the lower limit of the reference distance range, and 
     the communication control unit transmits the approach notification signal to the plurality of vehicles. 
     The image capturing system according to an eleventh aspect of the present invention, wherein the plurality of vehicles each further includes: 
     an acquisition unit configured to acquire location information of the vehicle; 
     a vehicle communication unit configured to transmit location information of the vehicle; and 
     a detection unit configured to detect speed information of the vehicle, the vehicle communication unit transmits the speed information to the control device, 
     the determination unit of the control device acquires a speed difference of the plurality of vehicles traveling in the image capturing area or the predetermined preparation area set before the image capturing area on the basis of the speed information, when the determination unit determines that the speed difference exceeds predetermined reference speed, 
     the signal generation unit 
     generates a speed notification signal that notifies the users that the speed difference exceeds the reference speed, and the communication control unit transmits the speed notification signal to the plurality of vehicles. 
     The image capturing system according to a twelfth aspect of the present invention, wherein the control device further includes: 
     a backlight determination unit configured to determine whether or not image capturing condition is backlight condition on the basis of image data. captured by the image capturing unit, and 
     when the image capturing condition is determined to be the backlight condition, the signal generation unit generates a flight control signal that instructs a change in a flight position of the unmanned aerial vehicle such that the unmanned aerial vehicle avoids the backlight, 
     the communication control unit transmits the flight control signal to the unmanned aerial vehicle, and 
     a flight control unit of the unmanned aerial vehicle changes the flight position on the basis of the flight control signal. 
     The image capturing system according to a thirteenth aspect of the present invention, wherein, when the image capturing condition is determined to be the backlight condition, the signal generation unit generates a parameter control signal that performs control to move an angle of view of the image capturing unit in a horizontal direction or control to move the angle of view of the image capturing unit in a vertical direction, 
     the communication control unit transmits the parameter control signal to the unmanned aerial vehicle, and 
     the image capturing control unit of the unmanned aerial vehicle 
     changes the angle of view of the image capturing unit on the basis of the parameter control signal. 
     The image capturing system according to a fourteenth aspect of the present invention, wherein the storage unit registers, as the subject information, user information in which a pedestrian or a user of a single vehicle constituting the subject is set as a target to be captured, and 
     the determination unit determines whether or not the subject has entered the predetermined image capturing area, on the basis of the location information of the subject and the map information. 
     The image capturing system according to a fifteenth aspect of the present invention, wherein, when the determination unit determines that the subject set as the target to be captured has entered the image capturing area, 
     the signal generation unit generates a control signal that instructs start of image capturing, and 
     the image capturing control unit controls the image capturing unit on the basis of the control signal to start capturing images of the subject. 
     The image capturing system according to a sixteenth aspect of the present invention, wherein, when the determination unit determines that the subject has entered the image capturing area or the predetermined preparation area set before the image capturing area, 
     the signal generation unit generates an area notification signal that notifies the subject that the subject has entered the image capturing area or the preparation area, and 
     the communication control unit transmits the area notification signal to the subject. 
     The image capturing system according to a seventeenth aspect of the present invention, wherein 
     the control device further includes: 
     an image processing unit configured to perform image processing of extracting a face of the subject from image data captured by the image capturing unit; and 
     an image determination unit configured to determine whether or not an image of the face of the subject has been captured on the basis of a result of the image processing, 
     when an image of the face of the subject has not been captured, the signal generation unit generates a parameter control signal that controls an image capturing parameter of the image capturing unit such that an image of the face of the subject can be captured, and 
     the image capturing control unit of the unmanned aerial vehicle 
     controls the image capturing unit on the basis of the parameter control signal to perform the image capturing. 
     The image capturing system according to an eighteenth aspect of the present invention, wherein, 
     when an image of the face of the subject has not been captured in determination of the image determination unit, 
     the signal generation unit generates an image capturing guide signal that guides the subject to redo the image capturing, and 
     the communication control unit transmits the image capturing guide signal to the subject. 
     A control device according to a nineteenth aspect of the present invention is a control device capable of communicating with an unmanned aerial vehicle including an image capturing unit capable of capturing an image of a subject in a flight state, the control device including: 
     a storage unit configured to register subject information in which the subject is set as a target to be captured: 
     a determination unit configured to determine whether the subject is present in a predetermined image capturing area, on the basis of location information of the subject and map information; 
     a signal generation unit configured to generate a control signal that controls the image capturing unit on the basis of determination of the determination unit; and 
     a communication control unit configured to transmit the subject information and the control signal to the unmanned aerial vehicle. 
     A control method according to a twentieth aspect of the present invention is a control method in a control device capable of communicating with an unmanned aerial vehicle including an image capturing unit capable of capturing an image of a subject in a flight state, the method including: 
     a storing step of registering, to a storage unit, subject information in which the subject is set as a target to be captured; 
     a determining step in which a determination unit determines whether the subject is present in a predetermined image capturing area, on the basis of location information of the subject and map information; 
     a signal generating step in which a signal generation unit generates a control signal that controls the image capturing unit on the basis of determination in the determining step; and 
     a communication controlling step in which a communication control unit transmits the subject information and the control signal to the unmanned aerial vehicle. 
     A storage medium according to a twenty-first aspect of the present invention is a computer-readable storage medium storing a program causing a computer to execute each step of a control method in a control device capable of communicating with an unmanned aerial vehicle including an image capturing unit capable of capturing an image of a subject in a flight state, wherein 
     the control method includes: 
     a storing step of registering, to a storage unit, subject information in which the subject is set as a target to be captured; 
     a determining step in which a determination unit determines whether the subject is present in a predetermined image capturing area, on the basis of location information of the subject and map information; 
     a signal generating step in which a signal generation unit generates a control signal that controls the image capturing unit on the basis of determination in the determining step; and 
     a communication controlling step in which a communication control unit transmits the subject information and the control signal to the unmanned aerial vehicle. 
     Advantageous Effects of Invention 
     According to the image capturing system of the first aspect of the present invention, a technology capable of capturing an image of a subject registered in advance using an unmanned aerial vehicle can be provided. 
     According to the image capturing system of the second aspect of the present invention, a technology capable of capturing an image of, using an unmanned aerial vehicle, a user traveling on a vehicle using users of a plurality of vehicles registered as a group in advance as a subject can be provided. 
     According to the image capturing system of the third aspect of the present invention, start timing of image capturing can be controlled, and an image of the vehicle that has entered the image capturing area first can be captured even when the image capturing area is small or the inter-vehicle distance between the vehicles in the group is large. 
     According to the image capturing system of the fourth aspect of the present invention, end timing of image capturing can be controlled, and images of a plurality of vehicles set as a group can be captured without omission. 
     According to the image capturing system of the fifth aspect of the present invention, start timing of image capturing can be controlled, an image can be captured when all the plurality of vehicles set as the group are in the image capturing area, and only the video that satisfies the needs of the users can be captured. 
     According to the image capturing system of the sixth aspect of the present invention, traveling in preparation for image capturing can be performed, such as aligning a platoon of vehicles in the group, by notifying the user of the area notification signal before image capturing. 
     According to the image capturing system of the seventh aspect of the present invention, by controlling the image capturing unit on the basis of the parameter control signal, images of the faces of all the members in the group can be captured. 
     According to the image capturing system of the eighth aspect of the present invention, even when images of the faces of all the users could not be captured, an image can be re-captured immediately in the image capturing area by generating the image capturing guide signal for guiding the user to redo image capturing and transmitting the image capturing guide signal to the plurality of vehicles. 
     According to the image capturing system of the ninth aspect of the present invention, when the inter-vehicle distance is too large, there is a possibility that images of the plurality of users cannot be simultaneously captured during traveling in the image capturing area. Accordingly, it is possible to prompt the user to reduce the inter-vehicle distance by transmitting, to a plurality of vehicles, the distance notification signal for notifying that the inter-vehicle distance exceeds a distance of the upper limit of the reference distance range to notify the users. 
     According to the image capturing system of the tenth aspect of the present invention, when the inter-vehicle distance is too small, there is a possibility that images of the plurality of users cannot be simultaneously captured due to overlap of the users during traveling in the image capturing area. Accordingly, it is possible to prompt the user to increase the inter-vehicle distance by transmitting, to the plurality of vehicles, the approach notification signal for notifying that the inter-vehicle distance is equal to or less than a distance of the lower limit of the reference distance range to notify the users. 
     According to the image capturing system of the eleventh aspect of the present invention, when the speed difference exceeds the reference speed, there is a possibility that the plurality of users cannot be simultaneously captured during traveling in the image capturing area. Accordingly, it is possible to prompt the user to reduce the speed difference by transmitting, to the plurality of vehicles, the speed notification signal for notifying that the speed difference exceeds the reference speed to notify the users. 
     According to the image capturing system of the twelfth aspect of the present invention, when it is determined that image capturing condition is backlight condition on the basis of the captured image data, an image can be captured while avoiding backlight by changing the flight position of the unmanned aerial vehicle. 
     According to the image capturing system of the thirteenth aspect of the present invention, when it is determined that image capturing condition is backlight condition on the basis of the captured image data, an image can be captured while avoiding backlight by changing the angle of view of the image capturing unit. 
     According to the image capturing system of the fourteenth aspect of the present invention, a technology capable of capturing an image of a pedestrian or a user of a single vehicle by an unmanned aerial vehicle, using the pedestrian or the user of the single vehicle registered in advance as a subject can be provided. 
     According to the image capturing system of a fifteenth aspect of the present invention, start timing of image capturing can be controlled. In this way, even when the image capturing area is small, an image of the subject can be captured without missing the timing of image capturing. 
     According to the image capturing system of the sixteenth aspect of the present invention, notifying the subject of the area notification signal before image capturing allows the subject to prepare for image capturing in advance. 
     According to the image capturing system of the seventeenth aspect of the present invention, by controlling the image capturing unit on the basis of the parameter control signal, an image of the face of the pedestrian or the user traveling using a single vehicle, both of which are subjects, can be captured. 
     According to the image capturing system of the eighteenth aspect of the present invention, even when an image of the face of the subject could not be captured, an image can be re-captured immediately in the image capturing area by generating the image capturing guide signal for guiding the subject to redo image capturing and transmitting the image capturing guide signal to the terminal of the subject. 
     According to the control device of the nineteenth aspect, the control method of the twentieth aspect, and the storage medium according to the twenty-first aspect of the present invention, a control technology for capturing an image of a subject registered in advance by using an unmanned aerial vehicle can be provided. 
    
    
     
       BRIEF DESCRIPTION OF HE DRAWINGS 
         FIG. 1  is a block diagram describing an example of an image capturing system according to a first embodiment. 
         FIG. 2  illustrates ST 21  that is a block diagram illustrating a functional configuration of an unmanned aerial vehicle, and ST 22  that is a block diagram illustrating a functional configuration of a processing unit. 
         FIG. 3  is a diagram schematically illustrating processing of a determination unit. 
         FIG. 4  is a diagram describing a flow of processing of a storage unit and the processing unit. 
         FIG. 5  is a diagram describing a flow of processing of an image processing unit and an image determination unit. 
         FIG. 6  is a diagram describing a flow of processing of adjusting an inter-vehicle distance between a plurality of vehicles. 
         FIG. 7  is a diagram describing a flow of processing of adjusting speed difference between a plurality of vehicles. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims, and not all combinations of features described in the embodiments are essential to the invention. 
     First Embodiment 
     Configuration of Image Capturing System 
       FIG. 1  is a diagram illustrating an example of the configuration of an image capturing system STM according to a first embodiment. The image capturing system STM includes an unmanned aerial vehicle DRN and a control device CNT (control server) capable of communicating with a terminal of a subject and the unmanned aerial vehicle DRN. The unmanned aerial vehicle DRN includes an image capturing unit  200  (camera) capable of capturing images of a plurality of vehicles in a flight state. The subject includes, for example, a pedestrian, a user of a single vehicle, or users of a plurality of vehicles. In the first embodiment, an example in which users of a plurality of vehicles constituting the subject is described as a group of targets to be captured will be described. 
     The control device CNT can remotely communicate with a plurality of vehicles  1 A and  1 B and the unmanned aerial vehicle DRN via a network NT, and can output a signal for controlling the unmanned aerial vehicle DRN via the network NT. 
     An information processing apparatus  18  is an external terminal that manages vehicle renting (vehicle use service). When a vehicle is rented to a user, user information (e.g., including terminal information of the user) for identifying the user and vehicle information for identifying the rented vehicle are transmitted to the control device CNT via the network NT. The information processing apparatus  18  (external terminal) can be installed, for example, in an external base (agency) such as a hotel, a rental-car vendor, or a dealer that provides sales or maintenance service of vehicles. 
     The external base (agency) can provide service of capturing an image of, by using the unmanned aerial vehicle DRN, users A and B traveling in the vehicles  1 A and  1 B using the plurality of users A and B who receive vehicle rental as a group GR. 
     When acquiring information (user information (including terminal information of the user) and vehicle information) transmitted from the information processing apparatus  18  (external terminal) via a communication interface unit  23  (communication I/F), the control device CNT registers, in a database DB of a storage unit  22 , subject information in which a subject is set as a target to be captured. When the users of the plurality of vehicles constituting the subject are set as the group of targets to be captured, the control device CNT registers, in the database DB of the storage unit  22 , group information in which the users A and B of the plurality of vehicles  1 A and  1 B are set as one group GR. Then, when a plurality of vehicles set as the group are traveling in a predetermined image capturing area, a processing unit  21  of the control device CNT generates a control signal for controlling the image capturing unit  200  of the unmanned aerial vehicle DRN, and transmits the control signal to the unmanned aerial vehicle DRN via the network NT. 
     The image capturing unit  200  of the unmanned aerial vehicle DRN can capture an image on the basis of a control signal transmitted from the control device CNT. The image captured by the image capturing unit  200  is transmitted to the control device CNT via the network NT and stored in the database DB of the storage unit  22 . The captured image can be confirmed (viewed) by using preview display on the information processing apparatus  18  (external terminal) or terminals of the plurality of users A and B, for example, mobile terminals SP (e.g., smartphones) at the time of returning the rented vehicle. If the user A or B likes the captured image the image data can be purchased. When the image data is purchased, the image data may be downloaded to the respective mobile terminals SP (smartphones) of the plurality of users A and B, or the image data can be stored in a storage medium such as a compact disc-read only memory (CD-ROM) or a digital versatile disc (DVD) to provide to the user. Specific functional configurations of the processing unit  21  of the control device CNT and the unmanned aerial vehicle DRN will be described in detail later. 
     In the embodiment, as an example of the plurality of vehicles, an electric motorcycle such as a straddle type vehicle can be used for the vehicles  1 A and  1 B, for example. Note that the straddle type vehicle refers to a type of vehicle in which a driver rides on a vehicle body, and the concept thereof includes a scooter type motorcycle and the like. 
     The vehicle A and the vehicle B have similar configurations, and the configuration of the vehicle  1 A will be described as a representative in the following description. Although  FIG. 1  illustrates an example of two vehicles  1 A and  1 B as an example of a plurality of vehicles, the present invention is not limited to this example, and three or more vehicles can form a group. 
     The vehicle  1 A includes a power source  11 , a battery  12  (power supply device) that supplies electric power to the vehicle, an operation mechanism  13 , a vehicle control device  14  that controls the vehicle, and a communication device  15 . In the embodiment, the power source  11  is an electric motor, and the battery  12  can supply electric power to the power source  11  and each element constituting the vehicle  1 . A rechargeable secondary battery is used as the battery  12 , for example. Examples thereof include a lead storage battery, a lithium-ion battery, and a nickel-hydrogen battery. The battery  12  can be charged by being coupled to a power supply capable of supplying a predetermined voltage via a cable. Alternatively, the battery  12  may be replaced with a charged battery at a battery-exchange station provided in the middle of the travel route, and the charged battery  12  may be mounted on the vehicle. 
     The operation mechanism  13  is configured to be able to input operation for controlling the power source  11 , and outputs a predetermined signal to the vehicle control device  14  described later on the basis of, for example, an operation input by a user. Examples of the operation input to the operation mechanism  13  include rotational operation using a predetermined key corresponding to the vehicle (ignition key, remote key, or the like), pressing operation using a pressing type switch (a start switch or the like). 
     The vehicle control device  14  is an electronic control unit (ECU) capable of controlling the operation of the entire vehicle  1 A, and can transmit and receive signals to and from each component of the vehicle  1 A via a predetermined signal line, for example. As an example, the vehicle control device  14  can receive a signal in accordance with an operation input to the operation mechanism  13  and control such that the power source  11  is started. 
     The function of the vehicle control device  14  can be implemented by any of software or hardware. For example, the function of the vehicle control device  14  may be implemented by a central processing unit (CPU) executing a predetermined program using a memory. Alternatively, the function of the vehicle control device  14  may be implemented by a publicly known semiconductor device such as a programmable logic device (PLD) or an application specific integrated circuit (ASIC). In addition, here, the vehicle control device  14  is described as a single element, but the vehicle control device  14  may be divided into two or more elements as necessary. 
     The communication device  15  includes an antenna for implementing communication with the control device CNT via the network NT. Furthermore, the communication device  15  includes a telematics control unit (TCU) or the like that performs signal processing for implementing communication with the control device CNT via the network NT. 
     The TCU can acquire voltage information indicating a voltage value of the battery  12  from the battery  12 , and the TCU can acquire control information indicating a control state of the vehicle  1  from the vehicle control device  14  (ECU). The TCU transmits, to the control device CNT via the network NT, the acquired voltage information of the battery  12  and control information of the vehicle control device  14  (ECU). In addition, the TCU can intervene in vehicle control in the vehicle control device  14  on the basis of information received from the control device CNT. 
     The communication device  15  can perform inter-vehicle communication between a plurality of vehicles constituting the group GR, and the communication device  15  of the vehicle  1 A can perform wireless communication with the other vehicle  1 B constituting the group GR and exchange information between the vehicles. The vehicle control device  14  can perform control such that, within the group GR, the speed and the vehicle distance during traveling in the image capturing area are adjusted by inter-vehicle communication between the vehicles. 
     A detection device  16  includes various sensors that detect various states of the vehicle  1 A, and examples thereof includes a gyro sensor, a global positioning system (GPS) sensor, and a vehicle speed sensor that detects vehicle speed information. The vehicle control device  14  can control the vehicle  1 A on the basis of the information detected by the detection device  16 , and the communication device  15  can transmit the detection result of the detection device  16  to the control device CNT via the network NT. 
     The gyro sensor detects a rotational motion of the vehicle  1 A. The vehicle control device  14  can determine the course of the vehicle  1 A by the detection result of the gyro sensor, the vehicle speed sensor, and the like. The GPS sensor detects the current location of the vehicle  1 A. In addition, the communication device  15  can communicate wirelessly with a server device that provides map information and traffic information, and acquire information of the current location of the vehicle  1 A. 
     In the embodiment, the communication device  15  and the detection device  16  function as an acquisition unit that acquires location information of the vehicle, and the communication device  15  functions as a vehicle communication unit that transmits the location information of the vehicle via the network NT. 
     A display device  17  is configured to be able to display the remaining battery level of the battery  12  and the notification information received from the control device CNT, together with the speedometer and the tachometer. When the notification information regarding the vehicle speed and the inter-vehicle distance between the vehicles in the group GR is received from the control device CNT during traveling in the image capturing area, the display device  17  can display the notification information to the user to prompt the user to adjust the vehicle speed and the inter-vehicle distance. This makes it possible to travel in the image capturing area in a state where the vehicle speed and the inter-vehicle distance are adjusted in the group GR as preparation for image capturing when capturing an image. 
     The control device CNT includes the processing unit  21 , the storage unit  22 , and the communication interface unit  23  (communication I/F), and is installed, for example, in a management company that provides vehicle use service. The processing unit  21  includes a processor including a CPU and a memory, and the storage unit  22  includes a random-access memory (RAM) serving as a processing area of a program, a ROM that stores various programs and data, and a hard disk drive (HDD) having relatively large capacity. Further, they may be distributed on a cloud. 
     For example, the processing unit  21  can communicate with the vehicles  1 A and  1 B and the unmanned aerial vehicle DRN via the network NT by the communication interface unit  23 , store information on the vehicles  1 A and  1 B and the unmanned aerial vehicle DRN in the storage unit  22 , or read information on the vehicles  1 A and  1 B and the unmanned aerial vehicle DRN from the storage unit  22 . In addition, image data captured by the image capturing unit  200  of the unmanned aerial vehicle DRN can be stored in the storage unit  22 . 
     When a vehicle is rented to a user, user information for identifying the user and vehicle information for identifying the rented vehicle are transmitted to the control device CNT via the network NT. The storage unit  22  registers subject information in which a subject is set as a target to be captured. Here, the subject information includes terminal information of the user and vehicle information of the vehicle used by the user. When users of a plurality of vehicles are subjects, the storage unit  22  can register group information in which the users of the plurality of vehicles are set as one group GR. In the example of  FIG. 1 , the group OR includes the user A who uses the vehicle  1 A and the user B who uses the vehicle  1 B. Although the group GR is one group in the example of  FIG. 1 , the storage unit  22  can register group information related to a plurality of groups. 
     Functional Configuration of Unmanned Aerial Vehicle DRN 
     Next, a functional configuration of the unmanned aerial vehicle DRN will be described. ST 21  in  FIG. 2  is a block diagram illustrating a functional configuration of the unmanned aerial vehicle DRN. The image capturing unit  200  is a camera mounted on the unmanned aerial vehicle DRN, and the image capturing unit  200  is configured to be able to capture an image of a plurality of vehicles by the unmanned aerial vehicle DIN in a flight state. The image capturing unit  200  of the unmanned aerial vehicle DRN can capture a still image or a moving image. 
     A communication interface unit  201  (communication I/F) can communicate with the vehicles  1 A and  1 B and the control device CNT via the network NT. The communication interface unit  201  transmits the image data captured by the image capturing unit  200  to the control device CNT. 
     An identification unit  202  identifies the subject on the basis of the subject information distributed from the terminal of the subject (mobile terminal SP) and the subject information transmitted from the control device CNT (communication control unit  230 ). Note that the information used to identify the subject is not limited to the subject information distributed from the terminal of the subject, and it is also possible to identify the plurality of vehicles constituting the group GR on the basis of the vehicle information distributed from the plurality of vehicles  1 A and  1 B and the vehicle information included in the subject information (group information) transmitted from the control device CNT. 
     When the unmanned aerial vehicle DRN captures an image, group information including vehicle information for identifying the vehicle is transmitted from the communication interface unit  23  of the control device CNT to the unmanned aerial vehicle DRN as information for identifying the group GR. In addition, the plurality of vehicles  1 A and  1 B distribute vehicle information for identifying the vehicles from the communication device  15  during traveling, and the identification unit  202  can identify the plurality of vehicles constituting the group GR on the basis of the group information transmitted from the communication interface unit  23  of the control device CNT by checking the vehicle information. 
     An image capturing control unit  203  controls the image capturing unit  200  on the basis of the control signal to control image capturing of the plurality of vehicles identified by the identification unit  202 . When receiving the control signal (parameter control signal) transmitted from the control device CNT, the image capturing control unit  203  can perform, on the basis of the control signal, control to move the angle of view of the image capturing unit  200  in the horizontal direction (pan control), control to move the angle of view of the image capturing unit  200  in the vertical direction (tilt control), and control to enlarge (zoom up) or reduce (zoom out) the angle of view and capture an image. 
     A rotor  204  rotates using a motor  205  as a drive source, and generates propulsive force of the unmanned aerial object DRN. In order to control the attitude in the flight state, the unmanned aerial vehicle DRN is provided with at least four rotors  204  and motors  205 , and a flight control unit  207  can control the output of each motor  205 . The flight control unit  207  can turn to change the flight position or change the flight altitude on the basis of the control signal transmitted from the control device CNT. 
     A sensor  206  is, for example, a distance sensor, and detects a distance between the plurality of vehicles identified by the identification unit  202  and the unmanned aerial vehicle DRN. 
     Functional Configuration of Processing Unit  21   
     Next, a specific functional configuration of the processing unit  21  of the control device CNT will be described. S 122  in  FIG. 2  is a block diagram illustrating a functional configuration of the processing unit  21 .  FIG. 3  is a diagram schematically illustrating processing of a determination unit  210 . 
     The determination unit  210  can perform various types of determination processing, and determines whether the subject is present in the predetermined image capturing area on the basis of the location information of the subject acquired by communication with the terminal of the subject and the map information. For example, when users of a plurality of vehicles are subjects, the determination unit  210  determines whether the plurality of vehicles  1 A and  1 B are traveling in the predetermined image capturing area on the basis of the map information and the location information of the plurality of vehicles  1 A and  1 B set as the group GR. The determination unit  210  can access the database of the map information constructed in the storage unit  22 , and the determination unit  210  compares the location information of the plurality of vehicles with the map information to determine whether or not the vehicle is traveling in the set image capturing area. 
     For example, as illustrated in ST 31  of  FIG. 3 , in a case where the determination unit  210  determines that at least one (vehicle  1 A) of the plurality of vehicles  1 A and  1 B set as the group GR has entered the image capturing area, for example, when the image capturing area is smaller (has a smaller distance) than the reference area, or when the inter-vehicle distance between the vehicles  1 A and  1 B in the group GR is large, the determination unit  210  determines that the plurality of vehicles  1 A and  1 B are traveling in the image capturing area. 
     Further, as illustrated in ST 32  of  FIG. 3 , in a case where all of the plurality of vehicles  1 A and  1 B set as the group GR enter the image capturing area, for example, when the image capturing area is larger (has a greater distance) than the reference area, the determination unit  210  determines that the plurality of vehicles is traveling in the image capturing area. 
     A signal generation unit  220  can generate various signals on the basis of the determination of the determination unit  210 , and for example, generates a control signal for controlling the image capturing unit  200  of the unmanned aerial vehicle DRN on the basis of the determination of the determination unit  210 . 
     When the determination unit  210  determines that the plurality of vehicles is traveling in the image capturing area in a state where image capturing is not started, the signal generation unit  220  generates a control signal for instructing the start of image capturing. 
     In addition, when the determination unit  210  determines that at least one of the plurality of vehicles is traveling in the image capturing area after image capturing is started, the signal generation unit  220  generates a control signal for instructing continuation of image capturing. 
     Then, as illustrated in ST 33  of  FIG. 3  when the determination unit  210  determines that all of the plurality of vehicles  1 A and  1 B have left the image capturing area, the signal generation unit  220  generates a control signal for instructing end of image capturing. 
     The communication control unit  230  can transmit the signal generated by the signal generation unit  220  via the communication interface unit  23 , and for example, transmits the control signal generated by the signal generation unit  220  to the unmanned aerial vehicle DRN via the communication interface unit  23 . 
     When image capturing is started, the communication control unit  230  transmits subject information and the control signal to the unmanned aerial vehicle DRN. When users of a plurality of vehicles are subjects, the storage unit  22  registers, as part of the subject information, group information in which users of the plurality of vehicles constituting the subjects are set as a group of targets to be captured. In this case, the communication control unit  230  transmits subject information (including group information) and the control signal to the unmanned aerial vehicle DRN. In this way, the identification unit  202  of the unmanned aerial vehicle DRN can identify the plurality of vehicles constituting the group GR on the basis of the group information, and images of the plurality of identified vehicles can be captured by the image capturing unit  200 . 
     Note that, when the determination unit  210  determines that at least one of the plurality of vehicles has entered the image capturing area or the predetermined preparation area set before the image capturing area, the signal generation unit  220  can generate an area notification signal for notifying the user that the vehicle has entered the image capturing area or the preparation area, and the communication control unit  230  can transmit the area notification signal to the plurality of vehicles. 
     Traveling in preparation for image capturing can be performed, such as aligning a platoon of vehicles in the group GR, by notifying the user of the area notification signal before image capturing. 
     When continuing image capturing or ending image capturing, the communication control unit  230  transmits, to the unmanned aerial vehicle DRN, a control signal for instructing continuation of image capturing or a control signal for instructing end of image capturing, both of which have been generated by the signal generation unit  220 . 
     The image capturing control unit  203  of the unmanned aerial vehicle DRN controls the image capturing unit  200  on the basis of a control signal for instructing continuation of image capturing to continue image capturing. In addition, the image capturing control unit  203  of the unmanned aerial vehicle DRN controls the image capturing unit  200  on the basis of a control signal for instructing end of image capturing to end image capturing. 
     An image processing unit  240  can perform image processing of extracting a face of a user from image data captured by the image capturing unit  200  of the unmanned aerial vehicle DRN. When the image data is a moving image, the image processing unit  240  performs image processing on an image of each frame. Furthermore, the image processing unit  240  can also perform image processing on an image sampled at a predetermined frame rate. 
     On the basis of the result of the image processing and the group information, an image determination unit  250  determines whether or not images of the faces of the users have been captured equivalent to the number of persons set as the group GR. For example, when the faces of the two users A and B set as the group GR are extracted by the image processing, that is, when the set number (N1) of the group GR is equal to the number of extraction (N2) extracted by the image processing (N1=N2), the image determination unit  250  determines that images of the faces of all the users constituting the group GR have been captured. 
     On the other hand, when the number of faces of the user extracted in the result of the image processing is one, that is, when the set number (N1=2) of the groups GR is not equal to the number of extraction (N2=1) extracted by the image processing (in this case, N1&gt;N2), the image determination unit  250  determines that images of the faces of the users has not been captured equivalent to the number of persons set as the group GR. 
     A backlight determination unit  260  determines whether or not it is in a backlight condition on the basis of the image data captured by the image capturing unit  200 . For example, when the image data captured by the image capturing unit  200  includes a region where the pixel value locally exceeds the reference pixel value, the backlight determination unit  260  can determine that such an image has been captured in the backlight image capturing condition. In this case, the signal generation unit  220  generates a flight control signal for instructing a change in the flight position of the unmanned aerial vehicle DRN so as to avoid backlight, or generates a control signal for changing the angle of view of the image capturing unit  200 . A specific processing will be described in the additional processing regarding the backlight determination after step S 570  in  FIG. 5 . 
     Processing Flow 
       FIG. 4  is a diagram for explaining the flow of processing of the storage unit  22  and the processing unit  21  (determination unit  210 , signal generation unit  220 , and communication control unit  230 ). 
     In step S 400 , the storage unit  22  registers information of the group GR. When the control device CNT acquires information (user information and vehicle information) transmitted from the information processing apparatus  18  (external terminal) via the communication interface unit  23 , the storage unit  22  registers, in the database DB, group information in which the users A and B of the plurality of vehicles  1 A and  1 B are set as one group GR. 
     In step S 405 , the determination unit  210  acquires map information from the database of map information constructed in the storage unit  22 . 
     In step S 410 , the determination unit  210  acquires the location information of the plurality of vehicles. In step S 415 , the determination unit  210  determines whether the plurality of vehicles  1 A and  1 B are traveling in a predetermined image capturing area on the basis of the location information of the plurality of vehicles  1 A and  1 B set as the group GR and the map information. 
     When the vehicles are not traveling in the image capturing area in the determination in step S 415  (NO in S 415 ), the determination unit  210  returns the processing to step S 410  and repeats the same processing. 
     On the other hand, when the vehicle is traveling in the image capturing area in the determination in step S 415  (YES in S 415 ), the process proceeds to step S 420 . 
     In step S 420 , the signal generation unit  220  generates a control signal for instructing start of image capturing, as a control signal for controlling the image capturing unit  200  of the unmanned aerial vehicle DRN on the basis of the determination of the determination unit  210 . 
     Then, in step S 425 , the communication control unit  230  transmits the information of the registered group GR and the generated control signal to the unmanned aerial vehicle DRN. 
     The identification unit  202  of the unmanned aerial vehicle DRN identifies the plurality of vehicles constituting the group GR on the basis of the group information, and images of the plurality of identified vehicles are captured by the image capturing unit  200 . 
     In step S 430 , the determination unit  210  determines whether all of the plurality of vehicles  1 A and  1 B have left the image capturing area. When all of the vehicles have not left the image capturing area (NO in S 430 ), that is, when the determination unit  210  determines that at least one of the plurality of vehicles is traveling in the image capturing area, the processing proceeds to step S 435 . 
     In step S 435 , the signal generation unit  220  generates a control signal for instructing continuation of image capturing. In step S 440 , the communication control unit  230  transmits, to the unmanned aerial vehicle DRN, a control signal for instructing continuation of image capturing, which has been generated by the signal generation unit  220 . When receiving the control signal for instructing the continuation of image capturing, the image capturing control unit  203  of the unmanned aerial vehicle DRN controls the image capturing unit  200  on the basis of a control signal for instructing continuation of image capturing to continue image capturing. 
     On the other hand, when the determination unit  210  determines that all of the plurality of vehicles  1 A and  1 B have left the image capturing area in the determination of step  5430  (YES in S 430 ), the signal generation unit  220  generates, in step S 445 , a control signal for instructing end of image capturing. 
     Then, in step S 450 , the communication control unit  230  transmits, to the unmanned aerial vehicle DRN, the control signal for instructing end of image capturing, which has been generated by the signal generation unit  220 . When receiving the control signal for instructing the end of image capturing, the image capturing control unit  203  of the unmanned aerial vehicle DRN controls the image capturing unit  200  on the basis of a control signal for instructing end of image capturing to end image capturing. 
     Processing Flow of Image Processing Unit and Image Determination Unit 
       FIG. 5  is a diagram describing a flow of processing of the image processing unit  240  and the image determination unit  250 . In step S 500 , the image processing unit  240  acquires image data captured by the image capturing unit  200  of the unmanned aerial vehicle DRN. 
     In step S 510 , the image processing unit  240  performs image processing of extracting the face of the user from the image data. 
     In step S 520 , on the basis of the result of the image processing acquired in step S 510  and the group information registered in advance, the image determination unit  250  performs image determination on whether or not images of the faces of the users have been captured equivalent to the number of persons set as the group GR. 
     When images of the faces of the users have been captured equivalent to the number of persons set as the group in the determination in step S 520  (YES in S 520 ), the process proceeds to step S 530 . 
     Then, in step S 530 , the storage unit  22  stores the captured image data in the database, and ends the processing. 
     The image data stored in the database can be provided to the preview display on the information processing apparatus  18  (external terminal) or the mobile terminals SP of the plurality of users A and B when the rented vehicle is returned. When the user A or B likes the captured image, such a user can purchase the image data. In this case, such a user can download the image data to the respective mobile terminals SP (smartphones) of the plurality of users A and B. It is also possible to store image data in a storage medium and provide the image data to the user. 
     On the other hand, when images of the faces of the users have not been captured equivalent to the number of persons set as the group in the determination in step S 520  (NO in S 520 ), the process proceeds to step S 540 . 
     In step S 540 , the signal generation unit  220  generates a parameter control signal for controlling the image capturing parameter. When images of the faces of the users have not been captured equivalent to the number of persons set as the group, the signal generation unit  220  generates a parameter control signal for controlling the image capturing parameters of the image capturing unit  200  such that images of the faces of the users (all the users) can be captured equivalent to the number of persons set as the group, The signal generation unit  220  can generate a parameter control signal for moving the angle of view of the image capturing unit  200  in the horizontal direction as the image capturing parameter for the pan control, or generate a parameter control signal for moving the angle of view of the image capturing unit  200  in the vertical direction as the image capturing parameter for the tilt control. Furthermore, a parameter control signal for capturing an image by enlarging (zooming up) or reducing (zooming out) the angle of view can be generated. 
     In step S 550 , the communication control unit  230  transmits the parameter control signal generated by the signal generation unit  220  to the unmanned aerial vehicle DRN. When receiving the parameter control signal, the image capturing control unit  203  of the unmanned aerial vehicle DRN controls the image capturing unit  200  on the basis of the parameter control signal to capture an image while moving using the unmanned aerial vehicle DRN. Images of the faces of all members in the group can be captured by controlling the angle of view of the image capturing unit  200  on the basis of the parameter control signal. 
     In step S 560 , the signal generation unit  220  generates an image capturing guide signal for the redoing of image capturing. When images of the faces of the users A and B have not been captured equivalent to the set number of persons in the determination of the image determination unit  250 , the signal generation unit  220  generates an image capturing guide signal for guiding the users A and B to redo image capturing. 
     Then, in step S 570 , the communication control unit  230  transmits the image capturing guide signal to the plurality of vehicles  1 A and  1 B. When receiving the image capturing guide signal the display device  17  of each vehicle presents a display based on the image capturing guide signal to the user, and guides the user to capture an image again. In this way, even when images of the faces of all the users could not be captured, an image can be re-captured immediately in the image capturing area by generating the image capturing guide signal and transmitting the image capturing guide signal to the plurality of vehicles. 
     After step S 570 , the processing returns to step S 500 , and thereafter, similar processing is repeatedly executed. 
     Additional Processing regarding Backlight Determination 
     Note that, after step S 570 , additional processing regarding backlight determination can be performed. The backlight determination unit  260  determines whether or not the image capturing condition is backlight condition on the basis of the image data captured by the image capturing unit  200 . For example, when the image data captured by the image capturing unit  200  includes a region where the pixel value locally exceeds the reference pixel value, the backlight determination unit  260  determines that such an image has been captured in the backlight condition. 
     When the image capturing condition is determined to be backlight condition, the signal generation unit  220  generates a flight control signal for instructing a change in the flight position of the unmanned aerial vehicle DRN so as to avoid backlight. For example, the signal generation unit  220  generates a flight control signal for instructing the unmanned aerial vehicle DRN to turn such that the sun does not come within the range of the viewing angle of the image capturing unit. 
     The communication control unit  230  transmits a flight control signal to the unmanned aerial vehicle DRN. When receiving the flight control signal, the flight control unit  207  of the unmanned aerial vehicle changes the flight position on the basis of the flight control signal. 
     Furthermore, when the image capturing condition is determined to be backlight condition, the signal generation unit  220  can also generate a control signal (parameter control signal) for performing control to move the angle of view of the image capturing unit  200  in the horizontal direction (pan control), or control to move the angle of view of the image capturing unit  200  in the vertical direction (tilt control). 
     The communication control unit  230  transmits a parameter control signal to the unmanned aerial vehicle DRN. When receiving the parameter control signal, the image capturing control unit  203  of the unmanned aerial vehicle DRN changes the angle of view of the image capturing unit  200  on the basis of the parameter control signal. 
     When the image capturing condition is determined to be backlight condition on the basis of the captured image data, an image can be captured while avoiding backlight by changing the flight position of the unmanned aerial vehicle or changing the angle of view of the image capturing unit  200 . 
     Processing of Adjusting Inter-vehicle Distance between Plurality of Vehicles 
     The control device CNT checks the inter-vehicle distance at the time when the plurality of vehicles  1 A and  1 B travel in the image capturing area or the predetermined preparation area set before the image capturing area, and transmits the notification information to the plurality of vehicles so as to ensure the inter-vehicle distance suitable for image capturing (distance falling within a predetermined reference distance range). 
     For example, when the inter-vehicle distance between the vehicles exceeds a distance of the upper limit of the predetermined reference distance range, a distance notification signal for notifying that the inter-vehicle distance is too large is transmitted to the plurality of vehicles  1 A and  1 B to notify the user of each vehicle. 
     When the inter-vehicle distance between the vehicles is equal to or less than a distance of the lower limit of the predetermined reference distance range, an approach notification signal for notifying that the inter-vehicle distance is too small is transmitted to the plurality of vehicles  1 A and  1 B to notify the user of each vehicle. 
       FIG. 6  is a diagram describing a flow of processing of adjusting an inter-vehicle distance between a plurality of vehicles. In step S 600 , the determination unit  210  acquires location information of the plurality of vehicles  1 A and  1 B traveling in the image capturing area or the predetermined preparation area set before the image capturing area. In step S 610 , the determination unit  210  acquires the inter-vehicle distance of the plurality of vehicles  1 A and  1 B on the basis of the location information. For example, the determination unit  210  can acquire the inter-vehicle distance on the basis of the difference in the location information. 
     In step S 620 , when determining that the acquired inter-vehicle distance exceeds the distance of the upper limit of the predetermined reference distance range (YES in S 620 ), the determination unit  210  advances the processing to step S 630 . 
     In step S 630 , the signal generation unit  220  generates a distance notification signal for notifying the user that the inter-vehicle distance exceeds the distance of the upper limit of the reference distance range. Then, in step S 640 , the communication control unit  230  transmits the distance notification signal to the plurality of vehicles  1 A and  1 B. When the inter-vehicle distance is too large, there is a possibility that images of a plurality of users cannot be simultaneously captured during traveling in the image capturing area, Accordingly, it is possible to prompt the user to reduce the inter-vehicle distance by transmitting, to a plurality of vehicles, a distance notification signal for notifying that the inter-vehicle distance exceeds a distance of the upper limit of the reference distance range to notify the users. 
     In step S 620 , when the acquired inter-vehicle distance does not exceed the distance of the upper limit of the predetermined reference distance range (NO in S 620 ), the determination unit  210  advances the processing to step S 650 . 
     In step S 650 , when the determination unit  210  determined that the acquired inter-vehicle distance is not equal to or less than the distance of the lower limit of the reference distance range (NO in S 650 ), the determination unit  210  returns the processing to step S 600  and repeatedly executes the same processing. In this case, the inter-vehicle distance between the plurality of vehicles  1 A and  1 B is an inter-vehicle distance suitable for image capturing (a distance falling within a predetermined reference distance range), and check processing of the inter-vehicle distance is continuously executed without generating the notification signals (distance notification signal, approach notification signal). 
     On the other hand, when the acquired inter-vehicle distance is equal to or less than the distance of the lower limit of the predetermined reference distance range in determination in step S 650  (YES in S 650 ), the determination unit  210  advances the processing to step S 660 . 
     In step S 660 , the signal generation unit  220  generates an approach notification signal for notifying the user that the inter-vehicle distance is equal to or less than the distance of the lower limit of the reference distance range. 
     Then, in step S 670 , the communication control unit  230  transmits the approach notification signal to the plurality of vehicles. When the inter-vehicle distance is too small, there is a possibility that images of a plurality of users cannot be simultaneously captured due to overlap of users during traveling in the image capturing area. Accordingly, it is possible to prompt the user to increase the inter-vehicle distance by transmitting, to a plurality of vehicles, an approach notification signal for notifying that the inter-vehicle distance is equal to or less than a distance of the lower limit of the reference distance range to notify the users. 
     Processing of Adjusting Speed Difference between Plurality of Vehicles 
     The control device CNT checks the speed difference between the vehicles at the time when the plurality of vehicles  1 A and  1 B travel in the image capturing area or the predetermined preparation area set before the image capturing area, and transmits the speed notification signal to the plurality of vehicles so as to ensure the speed difference suitable for image capturing (equal to or less than predetermined reference speed). 
       FIG. 7  is a diagram describing a flow of processing of adjusting speed difference between a plurality of vehicles. In step S 700 , the determination unit  210  acquires speed information of the plurality of vehicles  1 A and  1 B traveling in the image capturing area or a predetermined preparation area set before the image capturing area. In step S 710 , the determination unit  210  acquires the speed difference between the plurality of vehicles  1 A and  1 B on the basis of the speed information of the plurality of vehicles  1 A and  1 B. For example, the determination unit  210  can acquire the speed difference between the vehicles on the basis of the difference in the speed information. 
     In step S 720 , when the acquired speed difference does not exceed the reference speed (NO in S 720 ), the determination unit  210  returns the processing to step S 700  and repeatedly executes the same processing. In this case, the speed difference between the plurality of vehicles  1 A and  1 B is a speed difference suitable for image capturing (equal to or less than predetermined reference speed), and check processing of the speed difference is continuously executed without generating the speed notification signal. 
     On the other hand, when the speed difference exceeds the predetermined reference speed in determination in step S 720  (YES in S 720 ), the determination unit  210  advances the processing to step S 730 . 
     In step S 730 , the signal generation unit  220  generates a speed notification signal for notifying the user that the speed difference exceeds the reference speed. 
     Then, in step S 740 , the communication control unit  230  transmits the speed notification signal to the plurality of vehicles  1 A and  1 B. 
     When the speed difference exceeds the reference speed, there is a possibility that a plurality of users cannot be simultaneously captured during traveling in the image capturing area. Accordingly, it is possible to prompt the user to reduce the speed difference by transmitting, to a plurality of vehicles, the speed notification signal notifying that the speed difference exceeds the reference speed to notify the users. 
     Second Embodiment 
     In the first embodiment described above, the users of the plurality of vehicles constituting the subjects are described as the group of targets to be captured, but the configuration of the subject is not limited to this example, and may be, for example, a pedestrian or a user of a single vehicle. In a second embodiment, a configuration in which a pedestrian or a user of a single vehicle is a target to be captured will be described. The configuration of the image capturing system STM, and the functional configurations of the vehicle, the control device CNT and the unmanned aerial vehicle DRN are similar to those in  FIGS. 1 and 2 . Hereinafter, a portion differs from the first embodiment will be described. 
     In the second embodiment, the storage unit  22  of the control device CNT registers, as subject information, user information in which a single or a plurality of pedestrians or a user of a single vehicle constituting a subject, is set as a target to be captured. Here, the subject information includes terminal information of the user and vehicle information of the vehicle used by the user. When the subject is a pedestrian, in the subject information, terminal information of the pedestrian is registered in the storage unit  22  as subject information. 
     The determination unit  210  determines whether the subject is present in the predetermined image capturing area on the basis of the location information of the subject acquired by communication with the terminal of the subject (e.g., SP in  FIG. 1 ) and the map information. That is, the determination unit  210  determines whether or not the subject has entered the predetermined image capturing area ( FIG. 3 ) on the basis of the location information of the subject and the map information. When the determination unit  210  determines that the subject set as the target to be captured has entered the image capturing area, the signal generation unit  220  generates a control signal for instructing start of image capturing, and the communication control unit  230  transmits, to the unmanned aerial vehicle DRN, the control signal generated by the signal generation unit  220  and the subject information. 
     The identification unit  202  of the unmanned aerial vehicle DRN identifies the subject on the basis of the subject information distributed from the terminal of the subject and the subject information transmitted from the communication control unit  230 , and the image capturing control unit  203  of the unmanned aerial vehicle DRN controls the image capturing unit  200  on the basis of the control signal to start capturing an image of the subject. 
     Further, when the determination unit  210  determines that the subject has entered the image capturing area or the predetermined preparation area set before the image capturing area, the signal generation unit  220  generates an area notification signal for notifying the subject that the subject has entered the image capturing area or the preparation area, and the communication control unit  230  transmits the area notification signal to the subject. 
     In addition, the control device CNT includes, as a functional configuration, the image processing unit  240  that performs image processing of extracting the face of the subject from the image data captured by the image capturing unit, and an image determination unit  260  that determines whether or not an image of the face of the subject has been captured on the basis of the result of the image processing. 
     When an image of the face of the subject is not captured in the determination of the image determination unit  260 , the signal generation unit  220  generates a parameter control signal for controlling the image capturing parameter of the image capturing unit  200  such that an image of the face of the subject can be captured, and the communication control unit  230  transmits the generated parameter control signal to the unmanned aerial vehicle DRN. 
     The image capturing control unit  203  of the unmanned aerial vehicle DRN controls the image capturing unit  200  on the basis of the parameter control signal to capture an image of the subject. Furthermore, when an image of the face of the subject has not been captured in the determination of the image determination unit, the signal generation unit  220  generates an image capturing guide signal for guiding the subject to redo image capturing, and the communication control unit  230  transmits the image capturing guide signal to the terminal of the subject. When receiving the image capturing guide signal, the terminal of the subject presents a display based on the image capturing guide signal to the user, and guides the user to capture an image again. 
     Furthermore, when the subject is a user of a single vehicle, the communication control unit  230  can also transmit an image capturing guide signal to the vehicle of the user who is the subject. When receiving the image capturing guide signal, the display device  17  of the vehicle presents a display based on the image capturing guide signal to the user, and guides the user to capture an image again. In this way, even when images of the face of the user could not be captured, an image can be re-captured immediately in the image capturing area by generating the image capturing guide signal and transmitting the image capturing guide signal to the vehicle. 
     Summary of Embodiments 
     The above-described embodiments disclose at least configurations described as follows. 
     Configuration 1. An image capturing system according to the above embodiment is an image capturing system (e.g., STM in  FIG. 1 ) including; an unmanned aerial vehicle (e.g., DRN in  FIG. 1 ) including an image capturing unit (e.g.,  200  in  FIG. 1 ) capable of capturing an image of a subject in a flight state; and a control device (e.g., CNT in  FIG. 1 ) capable of communicating with a terminal of the subject (e.g., SP in  FIG. 1 ) and the unmanned aerial vehicle, in which 
     the control device (CNT) includes: 
     a storage unit (e.g.,  22  in  FIG. 1 ) configured to register subject information in which the subject is set as a target to be captured; a determination unit (e.g.,  210  in  FIG. 2 ) configured to determine whether the subject is present in a predetermined image capturing area, on the basis of location information of the subject acquired by communicating with the terminal and map information; 
     a signal generation unit (e.g.,  220  in  FIG. 2 ) configured to generate a control signal that controls the image capturing unit on the basis of determination of the determination unit; and 
     a communication control unit (e.g.,  230  in  FIG. 2 ) configured to transmit the subject information and the control signal to the unmanned aerial vehicle, and 
     the unmanned aerial vehicle (DRN) further includes: 
     an identification unit (e.g.,  202  in  FIG. 2 ) configured to identify the subject on the basis of subject distributed from the terminal of the subject and the subject information transmitted from the communication control unit; and 
     an image capturing control unit (e.g.,  203  in  FIG. 2 ) configured to control the image capturing unit on the basis of the control signal to control image capturing of the subject identified by the identification unit. 
     According to the image capturing system of Configuration 1, a technology capable of capturing an image of a subject registered in advance using an unmanned aerial vehicle can be provided. 
     Configuration 2. In the image capturing system according to the above embodiment, the storage unit registers, as the subject information, group information in which users of a plurality of vehicles constituting the subject are set as a group of targets to be captured, and 
     the determination unit determines, on the basis of location information of the subject and the map information, whether or not the subject is traveling in a predetermined image capturing area. 
     According to the image capturing system of Configuration 2, an image of a user traveling on a vehicle using users of a plurality of vehicles registered as a group in advance as a subject can be captured using the unmanned aerial vehicle. That is, according to the image capturing system of Configuration 1, images of users traveling in a plurality of vehicles can be simultaneously captured by the unmanned aerial vehicle on the basis of preset group information, and the image capturing system meeting the needs of the users who want to simultaneously capture images in a group. 
     Configuration 3. In the image capturing system according to the above embodiment, when the determination unit ( 210 ) determines that at least one of the plurality of vehicles set as the group has entered the image capturing area, the determination unit determines that the plurality of vehicles is traveling in the image capturing area, 
     the signal generation unit ( 220 ) generates a control signal that instructs start of image capturing, and 
     the image capturing control unit ( 230 ) controls the image capturing unit ( 200 ) on the basis of the control signal to start capturing images of the group of the plurality of vehicles ( 1 A,  1 B). 
     According to the image capturing system of Configuration 3, start timing of image capturing can be controlled, and an image of the vehicle that has entered the image capturing area first can be captured even when the image capturing area is small or the inter-vehicle distance between the vehicles in the group is large. 
     Configuration 4. In the image capturing system according to the above embodiment, when the determination unit ( 210 ) determines that at least one of the plurality of vehicles ( 1 A,  1 B) is traveling in the image capturing area, 
     the signal generation unit ( 220 ) generates a control signal that instructs continuation of image capturing, 
     the image capturing control unit ( 230 ) controls the image capturing unit on the basis of the control signal to continue the image capturing, 
     when the determination unit ( 210 ) determines that all of the plurality of vehicles have left the image capturing area, 
     the signal generation unit ( 220 ) generates a control signal that instructs end of image capturing, and 
     the image capturing control unit ( 230 ) controls the image capturing unit on the basis of the control signal to end the image capturing. 
     According to the image capturing system of Configuration 4, end timing of image capturing can be controlled, and images of a plurality of vehicles set as a group can be captured without omission. 
     Configuration 5. In the image capturing system according to the above embodiment, when the determination unit ( 210 ) determines that all of the plurality of vehicles ( 1 A,  1 B) set as the group have entered the image capturing area, the determination unit determines that the plurality of vehicles ( 1 A,  1 B) is traveling in the image capturing area, 
     the signal generation unit ( 220 ) generates a control signal that instructs start of image capturing, and 
     the image capturing control unit ( 230 ) controls the image capturing unit on the basis of the control signal to start capturing images of the group of the plurality of vehicles. 
     According to the image capturing system of Configuration 5, start timing of image capturing can be controlled, an image can be captured when all the plurality of vehicles set as the group are in the image capturing area, and only the video that meets the needs of the users can be captured. 
     Configuration 6. In the image capturing system according to the above embodiment, when the determination unit ( 210 ) determines that at least one of the plurality of vehicles ( 1 A,  1 B) has entered the image capturing area or a preparation area that is predetermined and set before the image capturing area, 
     the signal generation unit ( 220 ) generates an area notification signal that notifies the users that the at least one of the plurality of vehicles has entered the image capturing area or the preparation area, and 
     the communication control unit ( 230 ) transmits the area notification signal to the plurality of vehicles. 
     According to the image capturing system of Configuration 6, traveling in preparation for image capturing can be performed, such as aligning a platoon of vehicles in the group, by notifying the user of the area notification signal before image capturing. 
     Configuration 7. In the image capturing system according to the above embodiment, the control device (CNT) further includes: 
     an image processing unit (e.g.,  240  in  FIG. 2 ) configured to perform image processing of extracting faces of the users from image data captured by the image capturing unit; and 
     an image determination unit (e.g.,  250  in  FIG. 2 ) configured to determine whether or not images of the faces of the users have been captured equivalent to the number of persons se as the group on the basis of a result of the image processing and the group information, and 
     when images of the faces of the users have not been captured equivalent to the number of persons set as the group, the signal generation unit ( 220 ) generates a parameter control signal that controls an image capturing parameter of the image capturing unit such that images of the faces of the users can be captured equivalent to the number of persons set as the group, and 
     the image capturing control unit ( 203 ) of the unmanned aerial vehicle (DRN) 
     controls the image capturing unit on the basis of the parameter control signal to perform the image capturing. 
     According to the image capturing system of Configuration 7, by controlling the image capturing unit on the basis of the parameter control signal, images of the faces of all the members in the group can be captured. 
     Configuration 8. In the image capturing system according to the above embodiment, when images of the faces of the users have not been captured equivalent to the number of persons set as the group in determination of the image determination unit ( 250 ), 
     the signal generation unit ( 220 ) generates an image capturing guide signal that guides the users to redo the image capturing, and 
     the communication control unit ( 230 ) transmits the image capturing guide signal to the plurality of vehicles ( 1 A,  1 B). 
     According to the image capturing system of Configuration 8, even when images of the faces of all the users could not be captured, an image can be re-captured immediately in the image capturing area by generating the image capturing guide signal for guiding the user to redo image capturing and transmitting the image capturing guide signal to the plurality of vehicles. 
     Configuration 9, In the image capturing system according to the above embodiment, the determination unit ( 210 ) 
     acquires an inter-vehicle distance of the plurality of vehicles ( 1 A,  1 B) traveling in the image capturing area or the predetermined preparation area set before the image capturing area on the basis of the location information, and when the determination unit determines that the inter-vehicle distance exceeds a distance of an upper limit of a predetermined reference distance range, 
     the signal generation unit ( 220 ) 
     generates a distance notification signal that notifies the users that the inter-vehicle distance exceeds the distance of the upper limit of the reference distance range, and 
     the communication control unit ( 230 ) transmits the distance notification signal to the plurality of vehicles ( 1 A,  1 B). 
     According to the image capturing system of Configuration 9, when the inter-vehicle distance is too large, there is a possibility that images of the plurality of users cannot be simultaneously captured during traveling in the image capturing area. Accordingly, it is possible to prompt the user to reduce the inter-vehicle distance by transmitting, to a plurality of vehicles, the distance notification signal for notifying that the inter-vehicle distance exceeds a distance of the upper limit of the reference distance range to notify the users. 
     Configuration 10. In the image capturing system according to the above embodiment, the determination unit ( 210 ) 
     acquires an inter-vehicle distance of the plurality of vehicles ( 1 A,  1 B) traveling in the image capturing area or the predetermined preparation area set before the image capturing area on the basis of the location information, and when the determination unit determines that the inter-vehicle distance is equal to or less than a distance of a lower limit of a predetermined reference distance range, 
     the signal generation unit ( 220 ) 
     generates an approach notification signal that notifies the users that the inter-vehicle distance is equal to or less than the distance of the lower limit of the reference distance range, and 
     the communication control unit ( 230 ) transmits the approach notification signal to the plurality of vehicles ( 1 A,  1 B). 
     According to the image capturing system of Configuration 10, when the inter-vehicle distance is too small, there is a possibility that images of the plurality of users cannot be simultaneously captured due to overlap of the users during traveling in the image capturing area. Accordingly, it is possible to prompt the user to increase the inter-vehicle distance by transmitting, to the plurality of vehicles, the approach notification signal for notifying that the inter-vehicle distance is equal to or less than a distance of the lower limit of the reference distance range to notify the users. 
     Configuration 11. In the image capturing system according to the above embodiment, the plurality of vehicles ( 1 A,  1 B) each includes: 
     an acquisition unit (e.g., the communication device  15  and the detection device  16  in  FIG. 1 ) acquires location information of the vehicle; 
     a vehicle communication unit (e.g., the communication device  15  in  FIG. 1 ) configured to transmit location information of the vehicle; and 
     a detection unit (e.g.,  16  in  FIG. 1 ) configured to detect speed information of the vehicle, 
     the vehicle communication unit ( 15 ) transmits the speed information to the control device, 
     the determination unit ( 210 ) of the control device (CNT) acquires 
     a speed difference of the plurality of vehicles ( 1 A,  1 B) traveling in the image capturing area or the predetermined preparation area set before the image capturing area on the basis of the speed information, and when the determination unit determines that the predetermined speed difference exceeds reference speed, 
     the signal generation unit ( 220 ) 
     generates a speed notification signal that notifies the users that the speed difference exceeds the reference speed, and 
     the communication control unit ( 230 ) transmits the speed notification signal to the plurality of vehicles. 
     According to the image capturing system of Configuration 11, when the speed difference exceeds the reference speed, there is a possibility that the plurality of users cannot be simultaneously captured during traveling in the image capturing area. Accordingly, it is possible to prompt the user to reduce the speed difference by transmitting, to the plurality of vehicles, the speed notification signal for notifying that the speed difference exceeds the reference speed to notify the users. 
     Configuration 12. In the image capturing system according to the above embodiment, the control device (CNT) further includes: 
     a backlight determination unit (e.g.,  260  in  FIG. 2 ) configured to determine whether or not image capturing condition is backlight condition on the basis of image data captured by the image capturing unit, and 
     when the image capturing condition is determined to be the backlight condition, the signal generation unit ( 220 ) generates a flight control signal that instructs a change in a flight position of the unmanned aerial vehicle such that the unmanned aerial vehicle avoids the backlight, 
     the communication control unit ( 230 ) transmits the flight control signal to the unmanned aerial vehicle, and a flight control unit (e.g.,  207  in  FIG. 2 ) of the unmanned aerial vehicle (DRN) changes the flight position on the basis of the flight control signal. 
     According to the image capturing system of Configuration 12, when it is determined that image capturing condition is backlight condition on the basis of the captured image data, an image can be captured while avoiding backlight by changing the flight position of the unmanned aerial vehicle. 
     Configuration 13. In the image capturing system according to the above embodiment, when the image capturing condition is determined to be the backlight condition, the signal generation unit ( 220 ) generates a parameter control signal that performs control to move an angle of view of the image capturing unit ( 200 ) in a horizontal direction or control to move the angle of view of the image capturing unit ( 200 ) in a vertical direction, 
     the communication control unit ( 230 ) transmits the parameter control signal to the unmanned aerial vehicle, and 
     the image capturing control unit ( 203 ) of the unmanned aerial vehicle (DRN) 
     changes the angle of view of the image capturing unit ( 200 ) on the basis of the parameter control signal. 
     According to the image capturing system of Configuration 13, when it is determined that image capturing condition is backlight condition on the basis of the captured image data, an image can be captured while avoiding backlight by changing the angle of view of the image capturing unit. 
     Configuration 14. In the image capturing system according to the above embodiment, the storage unit ( 22 ) registers, as the subject information, user information in which a pedestrian or a user of a single vehicle constituting the subject is set as a target to be captured, and 
     the determination unit ( 210 ) determines whether or not the subject has entered the predetermined image capturing area, on the basis of the location information of the subject and the map information. 
     According to the image capturing system of Configuration 14, a technology capable of capturing an image of a pedestrian or a user of a single vehicle by an unmanned aerial vehicle, using the pedestrian or the user of the single vehicle registered in advance as a subject can be provided. 
     Configuration 15. In the image capturing system according to the above embodiment, when the determination unit ( 210 ) determines that the subject set as the target to be captured has entered the image capturing area, 
     the signal generation unit ( 220 ) generates a control signal that instructs start of image capturing, and 
     the image capturing control unit ( 203 ) controls the image capturing unit ( 200 ) on the basis of the control signal to start capturing images of the subject. 
     According to the image capturing system of Configuration 15, start timing of image capturing can be controlled. In this way, even when the image capturing area is small, an image of the subject can be captured without missing the timing of image capturing. 
     Configuration 16. In the image capturing system according to the above embodiment, when the determination unit ( 200 ) determines that the subject has entered the image capturing area or the predetermined preparation area set before the image capturing area, 
     the signal generation unit ( 220 ) generates an area notification signal that notifies the subject that the subject has entered the image capturing area or the preparation area, and the communication control unit ( 230 ) transmits the area notification signal to the subject. 
     According to the image capturing system of Configuration 16, notifying the subject of the area notification signal before image capturing allows the subject to prepare for image capturing in advance. 
     Configuration 17. In the image capturing system according to the above embodiment, the control device (CNT) further includes: 
     an image processing unit (e.g.,  240  in  FIG. 2 ) configured to perform image processing of extracting a face of the subject from image data captured by the image capturing unit ( 200 ); and 
     an image determination unit (e.g.,  250  in  FIG. 2 ) configured to determine whether or not an image of the face of the subject has been captured on the basis of a result of the image processing, 
     when an image of the face of the subject has not been captured, the signal generation unit ( 220 ) generates a parameter control signal that controls an image capturing parameter of the image capturing unit ( 200 ) such that an image of the face of the subject can be captured, and 
     the image capturing control unit ( 203 ) of the unmanned aerial vehicle (DRN) 
     controls the image capturing unit ( 200 ) on the basis of the parameter control signal to perform the image capturing. 
     According to the image capturing system of Configuration 17, by controlling the image capturing unit on the basis of the parameter control signal, an image of the face of the subject can be captured. 
     Configuration 18. In the image capturing system according to the above embodiment, when an image of the face of the subject has not been captured in determination of the image determination unit ( 250 ), 
     the signal generation unit ( 220 ) generates an image capturing guide signal that guides the subject to redo the image capturing, and 
     the communication control unit ( 230 ) transmits the image capturing guide signal to the subject. 
     According to the image capturing system of Configuration 18, even when an image of the face of the subject could not be captured, an image can be re-captured immediately in the image capturing area by generating the image capturing guide signal for guiding the subject to redo image capturing and transmitting the image capturing guide signal to the subject. 
     Configuration 19. A control device according to the above embodiment is a control device (e.g., CNT in  FIG. 1 ) capable of communicating with an unmanned aerial vehicle (e.g., DRN in  FIG. 1 ) including an image capturing unit (e.g.,  200  in  FIG. 2 ) capable of capturing an image of a subject in a flight state, and the control device includes: 
     a storage unit (e.g.,  22  in  FIG. 1 ) configured to register subject information in which the subject is set as a target to be captured; 
     a determination unit (e.g.,  210  in  FIG. 2 ) configured to determine whether the subject is present in a predetermined image capturing area, on the basis of location information of the subject and map information; 
     a signal generation unit (e.g.,  220  in  FIG. 2 ) configured to generate a control signal that controls the image capturing unit on the basis of determination of the determination unit; and 
     a communication control unit (e.g.,  230  in  FIG. 2 ) configured to transmit the subject information and the control signal to the unmanned aerial vehicle. 
     Configuration 20. A control method according to the above embodiment is a control method in a control device capable of communicating with an unmanned aerial vehicle including an image capturing unit capable of capturing an image of a subject in a flight state, and the control method includes: 
     a storing step (e.g., S 400  in  FIG. 4 ) of registering, to a storage unit ( 22 ), subject information in which the subject is set as a target to be captured: 
     a determining step (e.g., S 415  in  FIG. 4 ) in which a determination unit ( 210 ) determines whether the subject is present in a predetermined image capturing area, on the basis of location information of the subject and map information; 
     a signal generating step (e.g., S 420  in  FIG. 4 ) in which a signal generation unit ( 220 ) generates a control signal that controls the image capturing unit on the basis of determination in the determining step; and 
     a communication controlling step (e.g., S 425  in  FIG. 4 ) in which a communication control unit ( 230 ) transmits the subject information and the control signal to the unmanned aerial vehicle. 
     Configuration 21. A storage medium according to the above embodiment is a computer-readable storage medium storing a program causing a computer to execute each step of a control method in a control device capable of communicating with an unmanned aerial vehicle including an image capturing unit capable of capturing an image of a subject in a flight state, in which the control method includes: 
     a storing step (e.g., S 400  in  FIG. 4 ) of registering, to a storage unit ( 22 ), subject information in which the subject is set as a target to be captured; 
     a determining step (e.g., S 415  in  FIG. 4 ) in which a determination unit ( 210 ) determines whether the subject is present in a predetermined image capturing area, on the basis of location information of the subject and map information; 
     a signal generating step (e.g., S 420  in  FIG. 4 ) in which a signal generation unit ( 220 ) generates a control signal that controls the image capturing unit on the basis of determination in the determining step; and 
     a communication controlling step (e.g., S 425  in  FIG. 4 ) in which a communication control unit ( 230 ) transmits the subject information and the control signal to the unmanned aerial vehicle. 
     According to the control device of Configuration 19, the control method of Configuration 20 and the storage medium of Configuration 21, a control technology for capturing an image of a subject registered in advance by using an unmanned aerial vehicle can be provided. 
     The invention is not limited to the foregoing embodiments, and various variations/changes are possible within the spirit of the invention.