Video system and imaging apparatus

Abstract

Provided is a video system comprising a camera for capturing a video and a display device for displaying the video captured by the camera. The camera has an image sensor for capturing a video, an acceleration sensor for measuring acceleration on at least a Z-axis directed in the vertical direction, and an interface for outputting the photographed video and the acceleration on the Z-axis direction measured by the acceleration sensor. The display device has a display screen for outputting a video captured by the camera, and determines whether or not the video output from the camera is to be vertically inverted and displayed on the display screen according to whether the acceleration on the Z-axis direction output by the camera is positive or negative.

Description

Video system and imaging device Incorporation by Reference

[0001] This application claims priority from Japanese Patent Application No. 2023-128502, filed on August 7, 2023, the contents of which are incorporated herein by reference.

[0002] The present invention relates to a video system, and more particularly to a video system and an imaging device that allow drivers and crew members to check the movements of passengers around train doors.

[0003] In video systems installed on trains, train crew members check the safety of passengers by viewing images of passengers moving on the platform and operate the door opening and closing. Images of passengers are captured by cameras installed on the vehicle itself or on the platform. For example, there are systems in which images captured by cameras installed on the platform are displayed on a display device installed on the platform or on a display device installed in the train's driver's cab. There are also systems in which images captured by cameras installed on the side of the vehicle itself are displayed on a display device installed in the train's driver's cab.

[0004] The following prior art exists as background art in this technical field. For example, Patent Document 1 (WO 2016 / 51504) describes an IP communication system including a switching hub having at least first to (n+1)th ports (n is an integer of 2 or greater), first to nth IP devices connected to the first to nth ports, respectively, and an IP address setting device connected to the (n+1)th port, in which the IP address setting device transmits to the switching hub a first port open instruction that opens the first port and closes the second to nth ports, and then transmits a first IP address to be set to the first IP device, and the switching hub, upon receiving the first port open instruction from the IP address setting device, opens the first port and closes the second to nth ports, and upon receiving the first IP address, transmits the first IP address to the first IP device.

[0005] In video systems installed on trains, the camera images displayed on the display device differ depending on the direction of travel and the position of the platform. Also, depending on the direction in which the camera is installed, it may be necessary to flip the camera images upside down.

[0006] Conventionally, a predetermined inversion setting and address were set for each camera, and then the camera was installed in a predetermined location. When replacing a camera, the same inversion setting and address as the broken camera were set for the new camera, and then the new camera was installed in a predetermined location.

[0007] Furthermore, in the prior art described above, the setting device sets appropriate IP addresses and device information files (including information specifying the camera orientation, imaging angle, etc.) for multiple IP devices that have factory-set IP addresses. However, because this assumes that the correspondence between the port numbers of the switching hub and each IP device is predetermined, if the number or placement of IP devices changes, or if the wiring between the IP devices and the switching hub is incorrect, the IP addresses and device information files will no longer be set appropriately.

[0008] A representative example of the invention disclosed in the present application is as follows: That is, an imaging system includes a camera that captures images and a display device that displays the images captured by the camera, wherein the camera has an image sensor that captures images, an acceleration sensor that measures acceleration in at least a Z-axis oriented in the up-down direction, and an interface that outputs the captured image and the acceleration in the Z-axis direction measured by the acceleration sensor, and the display device has a display screen that outputs the images captured by the camera, and determines whether to display the images output from the camera upside down on the display screen depending on whether the acceleration in the Z-axis direction output by the camera is positive or negative.

[0009] In addition, in one example of the video system of the present invention, the acceleration sensor measures acceleration on the horizontal X-axis, with the shooting direction being positive, and the display device selects an image to be displayed on the display screen depending on whether the acceleration in the X-axis direction output by the camera is positive or negative.

[0010] In addition, in the video system according to one example of the present invention, the display device selects the video to be displayed on the display screen based on information acquired from the traffic management device.

[0011] Furthermore, an example of an imaging device of the present invention includes an image sensor that captures an image, an acceleration sensor that measures acceleration in at least the Z-axis oriented in the vertical direction, and an interface that outputs the captured image and the acceleration in the Z-axis direction measured by the acceleration sensor, and is characterized in that it outputs the positive or negative acceleration in the Z-axis direction in order to determine whether a display device should display the image upside down on a display screen.

[0012] In addition, in one example of the video system of the present invention, the acceleration sensor measures acceleration on the horizontal X-axis, with the shooting direction being positive, and outputs positive or negative acceleration in the X-axis direction so that the display device can select an image to be displayed on the display screen.

[0013] According to one aspect of the present invention, it is possible to eliminate the need to set inversion settings and addresses when building a video system or replacing a camera. Problems, configurations, and effects other than those described above will become apparent from the following description of the preferred embodiment of the present invention.

[0014] 1 is a diagram showing an example of the configuration of a monitoring system according to an embodiment of the present invention. FIG. 2 is a diagram showing the configuration of a camera according to this embodiment. FIG. 3 is a diagram showing the appearance of a camera according to this embodiment. FIG. 4 is a diagram showing the installation state of a camera according to this embodiment. FIG. 5 is a diagram showing an example of installation information collected from a camera according to this embodiment. FIG. 6 is a diagram showing an example of installation information collected from a camera according to this embodiment. FIG. 7 is a flowchart of processing executed by a video system according to this embodiment. FIG. 8 is a decision table showing how camera images are handled by a display device as a result of the processing shown in FIG.

[0015] An embodiment of the present invention will be described with reference to the drawings.

[0016] FIG. 1 is a diagram showing an example of the configuration of a video system 100 according to an embodiment of the present invention.

[0017] The video system 100 shown in Fig. 1 is mounted on a train consisting of three cars, cars 111 to 113. The number of cars included in a train formation is not limited to three. When car 111 is the front car, the third car 113 is the rearmost car. Conversely, when car 113 is the front car, the third car 111 is the rearmost car.

[0018] Video system 100 includes cameras 131 to 134, display devices 141 to 142, a server 151, a recording device 152, and a host server 153. These devices are connected via a switching hub 135. Power supply cables are also connected to these devices, and power is supplied from a power supply unit (not shown) in each vehicle.

[0019] Each of the cars 111 to 113 is equipped with four cameras 131 to 134 and a switching hub 135. Two display devices 141 to 142 are installed in the driver's cab of the first car 111 and the third car 113. The cameras 131 to 134 and display devices 141 to 142 of each car are connected via the switching hub 135 of that car. Furthermore, the car 111 is equipped with a server 151, a recording device 152, and a host server 153. The server 151 and the recording device 152 are connected via the switching hub 135, and the host server 153 is connected to the server 151. Note that the third car 113 may be equipped with the same server 151 and host server 153 as the first car 111, thereby multiplexing the server 151 and the host server 153.

[0020] The switching hub 135 of each car is connected to the switching hub 135 of an adjacent car by a network cable. By connecting the switching hubs 135 of adjacent cars in this way, a single network is formed within the train. These network cables are connected to a jumper box (not shown), for example, via under the car floor, and between cars, it is preferable to connect the jumper boxes of adjacent cars with jumper wires.

[0021] The cameras 131 to 134 capture video within a predetermined field of view (angle of view) at a predetermined frame rate. The cameras 131 to 134 also convert the captured video (live video) into a format such as H.264, MPEG4, or JPEG, and transmit the converted video to the recording device 152 and the display devices 141 to 142 via the switching hub 135.

[0022] In the direction A of train travel (car 111 is the lead car), cameras 131 and 132 are installed on the right side of the car, and cameras 133 and 134 are installed on the left side of the car. Also, in the direction A of train travel (car 111 is the lead car), cameras 131 and 134 are installed in positions that allow them to take pictures from the front to the rear of the car, and cameras 132 and 133 are installed in positions that allow them to take pictures from the rear to the front of the car. In the direction B of train travel (car 113 is the lead car), the left and right and front and rear are reversed from those described above.

[0023] The cameras 131 to 134 are usually mounted above the vehicle and are mounted at an angle facing downward so that they can capture images of passengers getting on and off through the doors from above the vehicle. Also, a camera 131 that takes images from the front to the rear and a camera 132 that takes images from the rear to the front are mounted on one side of each vehicle, and a camera 133 that takes images from the front to the rear and a camera 134 that takes images from the rear to the front are mounted on the other side.

[0024] The cameras installed on the same side are used differently depending on the direction of travel of the train. For example, when traveling in direction A, where car 111 is the lead car, cameras 131 and 134 are used, which take pictures from the front to the rear, where there is less chance of foreign matter adhering while the train is moving. Similarly, when traveling in direction B, where car 113 is the lead car, cameras 132 and 133 are used, which take pictures from the front to the rear, where there is less chance of foreign matter adhering while the train is moving. Note that if cameras 131 and 134 fail, cameras 132 and 133 are used as backups. If cameras 132 and 133 fail, cameras 131 and 134 are used as backups.

[0025] The cameras 131 to 134 automatically capture images at a predetermined frame rate and transmit the captured images to the recording device 152 and the display devices 141 to 142. Alternatively, the cameras 131 to 134 transmit the captured images to the recording device 152 and the display devices 141 to 142 in response to a transmission request transmitted from the display devices 141 to 142 via the switching hub 135. Whether the cameras 131 to 134 transmit images automatically or in response to a transmission request is set when the system starts operating, but the crew can switch between these modes by operating the server 151.

[0026] The server 151 is a control device that performs display control such as switching between images captured by the cameras 131 to 134 and displaying them on the display devices 141 to 142 .

[0027] The server 151 or the switching hub 135 has a DHCP function. This DHCP function automatically assigns IP addresses to the cameras 131 to 134. The IP addresses assigned to the cameras 131 to 134 may be fixed IP addresses rather than assigned by the DHCP function. If the switching hub 135 provides the DHCP function, the range in which the DHCP function is provided may be limited for each vehicle.

[0028] Recording device 152 records the images captured by cameras 131 to 134 in association with the camera that captured the image and the time of capture.

[0029] The host server 153 is, for example, an operation management device that manages train operations, and for example, a Train Management System (TMS) is used. The host server 153 outputs train operation information to the server 151 at predetermined timings (for example, at predetermined time intervals) while the train is in operation. The train operation information includes train speed information, boarding / alighting door opening / closing information (information on whether passenger boarding / alighting doors are open or closed), boarding / alighting door information on the platform of the next station or the current station (for example, information on whether the boarding / alighting door is on the left side or the right side), train length, train traveling direction information, etc.

[0030] The display devices 141-142 display live images from all cameras 131-134 or recorded images recorded on the recording device 152 side by side after performing processing such as trimming and flipping in accordance with instructions from the server 151. The recorded images are mainly used for analyzing accidents and crimes when they occur.

[0031] The two display devices 141-142 are preferably arranged side by side, either vertically or horizontally, so that they can be viewed simultaneously by the crew. The display devices 141-142 have a total of six divided display areas, with the display screen divided into two vertically and three horizontally. Therefore, one display device can simultaneously display camera images of a three-car train (images from a total of six cameras on one side of the train). Furthermore, by using two display devices together, camera images of a maximum six-car train can be simultaneously displayed.

[0032] Major settings of the server 151, display devices 141-142, cameras 131-134, and recording device 152 are set at the start of system operation. In this embodiment, the display devices 141-142 have a display control unit for displaying multiple videos side by side, but a display control unit may also be provided in the server 151. That is, the server 151 may generate display data for displaying multiple videos side by side, transmit it to the display devices 141-142, and display it on the display devices 141-142. In addition, it is preferable that the cameras 131-134 measure acceleration in the Z-axis direction at the start of system operation and set the display devices 141-142 to flip the images upside down.

[0033] The crew member rides in the car at the front of the train (for example, the first car 111) in the direction of travel, and operates the train (driving, opening and closing the doors, etc.) by himself.

[0034] The crew can check the images captured by the cameras 131 to 134 on display devices 141 to 142 installed in the car at the front of the train in the direction of travel. That is, when car 111 is the leading car, the images are displayed on display devices 141 to 142 of the first car 111, and when car 113 is the leading car, the images are displayed on display devices 141 to 142 of the third car 113.

[0035] 2 is a diagram showing the configuration of the camera 131 of this embodiment. Although the camera 131 will be described in FIG. 2, the cameras 132 to 134 also have the same configuration.

[0036] The camera 131 of this embodiment is a network camera capable of outputting video data via a network, and has a light receiving window 81, a lens 83, an image sensor 85, a signal processing unit 87, an image processing unit 89, an encoder unit 90, a control unit 86, and an acceleration sensor 88.

[0037] Camera 131 has a light receiving window 81 and a lens 83 inside light receiving window 81. Lens 83 is a wide-angle lens that can monitor a relatively wide range of doors, and its field of view is in the range 91 to 92. Although lens 83 is shown as a single convex lens, it may actually be configured by combining multiple lenses.

[0038] The light collected by the lens 83 is incident on the image sensor 85. The image sensor 85 generates raw image data (e.g., RAW data) by photoelectric conversion. A signal processing unit 87 performs signal processing such as noise removal and edge processing to clarify contours from the raw image data, and generates image data.

[0039] The image processing unit 89 cuts out a necessary area from the image data generated by the signal processing unit 87 and inputs the generated image to the encoder unit 90 .

[0040] The encoder unit 90 converts the image data into a predetermined data format (for example, JPEG / H.264) to generate video data. The generated video data is output to the network via a physical interface 91.

[0041] The control unit 86 has a CPU and logic circuits that execute programs, and controls the operations of the image sensor 85, signal processing unit 87, image processing unit 89, and encoder unit 90, as well as the output of attachment information, which will be described later.

[0042] The acceleration sensor 88 is a multi-axis acceleration sensor (for example, a triaxial acceleration sensor that measures acceleration in three orthogonal directions, X, Y, and Z) that measures at least the acceleration on the X-axis in the shooting direction and the acceleration on the Z-axis in the vertical direction. The cameras 131 to 134 are usually mounted above the vehicle, and are therefore mounted at an angle downward from the horizontal so that they can capture images of the doors from above the vehicle, as shown in Figures 4A and 4B. Therefore, the direction of travel of the train can be detected based on the acceleration on the X-axis.

[0043] As shown in Figures 3A and 3B, cameras 131 to 134 have flanges 132A, 132B, 131A, and 131B on one side, and are attached to the vehicle side by screws through screw holes 132C and 131C. Therefore, the images captured by cameras 131 to 134 are inverted upside down depending on the mounting position and orientation. For example, as shown in Figure 3A, camera 132, which is installed facing the vehicle side so as to capture images to the right, is attached to the vehicle side so that the light receiving window 81 is located on the right, the first flange 132A is located on the top, and the second flange 132B is located on the bottom. Also, as shown in Figure 3B, camera 131, which is installed facing the vehicle side so as to capture images to the left, is attached to the vehicle side so that the light receiving window 81 is located on the left, the first flange 131A is located on the bottom, and the second flange 131B is located on the top. Since the same camera 131 and camera 132 are used, if the image output from camera 132 is in the normal position, then the image output from camera 131 is an inverted image that is upside down.

[0044] As shown in FIG. 3A , the camera 132 is defined with a horizontal X-axis with the shooting direction (right side) as positive and a vertical Z-axis with the top as positive. These coordinate axes are determined by the acceleration sensor 88 described above, and the acceleration measured changes depending on the mounting position and orientation of the camera. The horizontal X-axis may be defined with the shooting direction (right side) as negative, and the vertical Z-axis may be defined with the bottom as positive. The X-axis is preferably the shooting direction, but it may also be a horizontal axis that differs from the shooting direction by a small angle. The Z-axis is preferably vertical, but it may also be an up-down axis that differs from the vertical direction by a small angle. That is, for a camera 131 with a different mounting position and orientation, as shown in FIG. 3B , the horizontal X-axis is defined with the shooting direction (left side) as positive and the vertical Z-axis is defined with the bottom as positive.

[0045] The camera 131 outputs attachment information, which changes depending on the attachment direction, to the network via the physical interface 91. The attachment information includes X-axis acceleration, which changes depending on the direction of train travel, and Z-axis acceleration, which changes depending on the attachment direction. Note that the X-axis acceleration and Z-axis acceleration do not have to be numerical values, and may be information indicating whether the values ​​are positive or negative. The camera 131 may notify the network of the attachment information by repeatedly broadcasting it (for example, at predetermined time intervals), but may also notify the attachment information by a method other than broadcasting.

[0046] As shown in Figure 4A, when the train's direction of travel is A (car 111 is the lead car), camera 131 measures negative acceleration in the X-axis direction shown by the thick line while accelerating in a powered state, and measures positive gravitational acceleration in the Z-axis direction shown by the thick line.

[0047] Camera 132, which is installed on the same side of the train as camera 131 so as to capture images in the opposite direction, measures positive acceleration in the X-axis direction shown by the thick line and negative acceleration in the Z-axis direction shown by the thick line during acceleration in a powered state when the train is traveling in direction A (car 111 is the lead car), as shown in Figure 4B.

[0048] In this way, the mounting positions and mounting orientations of the cameras 131 to 134 can be detected based on the positive and negative accelerations in the X-axis direction and Z-axis direction of the mounting information output from the cameras 131 to 134.

[0049] The display devices 141-142 receive the installation information output from the cameras 131-134, extract the IP addresses of the cameras 131-134, and the accelerations in the X- and Z-axes from the received installation information, create the data shown in Figures 5A and 5B, and store them in memory. Because the acceleration in the X-axis direction varies depending on the train's acceleration / deceleration and direction of travel, the acceleration in the X-axis direction during powering is collected, but the acceleration in the Z-axis direction only needs to be measured once, either at the start of system operation or when the cameras 131-134 are installed. The acceleration in the Z-axis direction may be stored in the cameras 131-134 or in the display devices 141-142. Note that the numbers of the cameras 131-134 are provided for convenience in the following explanation and are not actually required data. The installation information may be collected by the display devices 141-142 or by the server 151.

[0050] 5A shows an example of attachment information collected in train traveling direction A (car 111 is the leading car), and FIG. 5B shows an example of attachment information collected in train traveling direction B (car 113 is the leading car). In train traveling direction A (car 111 is the leading car) and train traveling direction B (car 113 is the leading car), the acceleration data in the X-axis direction, which is determined by the train traveling direction, has an opposite sign, and the acceleration data in the Z-axis direction, which is determined by the camera mounting position, has the same sign.

[0051] FIG. 6 is a flowchart of the process executed by the video system 100 of this embodiment.

[0052] The start and stop of video distribution from the cameras 131-134 on each vehicle is controlled via the network. When the train begins operation, the display devices 141-142 acquire and store information on the image clipping frame of each camera and split display control information from the server 151, and control the split display based on the acquired information. The split display control information includes information on the split format of the monitor's display area and information on the display number that identifies each split area.

[0053] The server 151 determines whether the train has stopped at a station based on the train speed information and location information in the operation information received from the upper server 153 (S11). For example, if the train speed is 0 and the location is a station, it can be determined that the train has stopped at a station. The train speed may be determined to be equal to or lower than a predetermined speed (e.g., 3 km / h) rather than using 0 as a threshold.

[0054] When the server 151 determines in step S11 that the train is stopped at a station, it determines whether the doors of the vehicle are open or not based on the boarding / alighting door opening / closing information in the operation information (S12).

[0055] If the server 151 determines in step S11 that the train is not stopped at a station, or if the server 151 determines in step S12 that the vehicle doors are not open, it sends a command to stop displaying the image to the display devices 141 to 142 (S13). Note that if image display has not started, no action is required. After this, the process returns to step S11 and repeats the process.

[0056] On the other hand, if the server 151 determines in step S12 that the vehicle door is open, it acquires one line of the collected attachment information (S14).

[0057] Then, the display devices 141-142 determine whether the acceleration on the X axis is a positive value (S15). If the acceleration on the X axis is a positive value, the image from this camera is captured from the rear to the front of the train, so the image from this camera is not used and the process returns to step S14 to obtain the attachment information for the next row.

[0058] On the other hand, if the acceleration on the X axis is a negative value, the train is being photographed from the front to the rear, so it is determined whether the door that is open is the right door (S16).

[0059] If the right door is open, it is determined whether the Z-axis acceleration is a positive value (S17). If the Z-axis acceleration is a negative value, the image from this camera is not used, and the process returns to step S14 to acquire the installation information for the next row. On the other hand, if the Z-axis acceleration is a positive value, the camera is used to check whether passengers are getting in and out of the door, so a video acquisition request is sent to the IP address and the image is acquired (S18). The acquired image is then displayed on the display screen (S19).

[0060] On the other hand, if the left door is open, it is determined whether the Z-axis acceleration is a negative value (S20). If the Z-axis acceleration is a negative positive, the image from this camera is not used, and the process returns to step S14 to acquire the installation information for the next row. On the other hand, if the Z-axis acceleration is a negative value, the camera is used to check whether passengers are getting in and out of the door, so a video acquisition request is sent to the IP address and the image is acquired (S21). In this case, the acquired image is upside down, so the display devices 141-142 invert the acquired image and display it on their display screens (S22). The image inversion process may be performed by the display devices 141-142, or may be performed by the cameras 131-134 to output the inverted image.

[0061] For example, when vehicle 111 is the lead vehicle in direction A and the right door is opened, display devices 141-142 measure negative acceleration in the X-axis direction and transmit an image acquisition request to the IP address (172.16.2.1) of camera 131 that measures positive acceleration in the Z-axis direction. Note that, when displaying images of both sides regardless of which door is open, image acquisition requests may be sent to the IP addresses (172.16.2.1, 172.16.2.3) of two cameras 131 and 134 that measure negative acceleration in the X-axis direction.

[0062] As a result of the processing shown in FIG. 6, the images output from the cameras 131 to 134 are handled as shown in FIG. 7 by the display devices 141 to 142 depending on the direction of travel of the train.

[0063] 6, the display devices 141 and 142 select the image to be displayed on the display screen depending on whether the acceleration in the X-axis direction output by the camera is positive or negative, but the image to be displayed on the display screen may also be selected based on traffic control information obtained from the upper server 153. For example, the image to be displayed on the display screen may also be selected based on the direction of travel of the train and information on whether the left door or the right door is open.

[0064] As described above, according to the embodiment of the present invention, it is possible to eliminate the need to set the inversion setting and IP address when starting operation of the video system. Furthermore, when replacing a camera due to failure, it is possible to install a new camera without setting the same inversion setting and IP address as the failed camera.

[0065] The present invention is not limited to the above-described embodiments, and includes various modifications and equivalent configurations within the spirit and scope of the appended claims. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to configurations including all of the described configurations. Furthermore, part of the configuration of one embodiment may be replaced with the configuration of another embodiment. Furthermore, the configuration of another embodiment may be added to the configuration of one embodiment. Furthermore, part of the configuration of each embodiment may be added, deleted, or replaced with other configurations.

[0066] Furthermore, the aforementioned configurations, functions, processing units, processing means, etc. may be realized in part or in whole in hardware, for example by designing them as integrated circuits, or may be realized in software by having a processor interpret and execute a program that realizes each function.

[0067] Information such as programs, tables, and files that realize each function can be stored in a storage device such as a memory, hard disk, or SSD (Solid State Drive), or in a recording medium such as an IC card, SD card, or DVD.

[0068] In addition, the control lines and information lines shown are those that are considered necessary for explanation, and do not necessarily represent all the control lines and information lines that are necessary for implementation. In reality, it can be assumed that almost all components are interconnected.

Claims

1. A video system comprising: a camera that captures video; and a display device that displays the video captured by the camera, wherein the camera has an image sensor that captures video, an acceleration sensor that measures acceleration in at least the vertical Z-axis, and an interface that outputs the captured video and the acceleration in the Z-axis direction measured by the acceleration sensor, and the display device has a display screen that outputs the video captured by the camera, and the video system determines whether to display the video output from the camera upside down on the display screen depending on whether the acceleration in the Z-axis direction output by the camera is positive or negative.

2. An imaging system as claimed in claim 1, characterized in that the acceleration sensor measures the acceleration on the horizontal X-axis, with the shooting direction being taken as positive, and the display device selects the image to be displayed on the display screen depending on the positive or negative value of the acceleration in the X-axis direction output by the camera.

3. A video system as claimed in claim 1, characterized in that the display device selects the video to be displayed on the display screen based on information obtained from an operation management device.

4. An imaging device comprising: an image sensor for capturing images; an acceleration sensor for measuring acceleration along at least the Z-axis oriented in the vertical direction; and an interface for outputting the captured image and the acceleration along the Z-axis measured by the acceleration sensor, the imaging device outputting the positive or negative acceleration along the Z-axis in order to determine whether a display device should display the image upside down on a display screen.

5. An imaging device according to claim 4, wherein the acceleration sensor measures acceleration on the horizontal X-axis, with the shooting direction being taken as positive, and outputs the positive or negative acceleration in the X-axis direction so that the display device can select an image to be displayed on the display screen.

Images