Communication equipment and communication methods

Abstract

To provide a communication device and a communication method with which it is possible to quickly transmit images.SOLUTION: According to an embodiment, a communication device that is installed in a mobile entity comprises a first communication unit, a second communication unit, a storage unit, and a processor. The first communication unit transmits and receives data to and from an external device which is installed on the ground. The second communication unit transmits and receives data to and from a camera. The storage unit stores the data. The processor is connected by a prescribed protocol to the camera through the second communication unit, and acquires, through the second communication unit, image data captured by the camera, compresses the image data to generate a compressed image, and stores the compressed image in the storage unit. When an acquisition command is received from the external device through the first communication unit, the processor transmits the compressed image which is stored in the storage unit to the external device.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] Embodiments of the present invention relate to a communication device and a communication method.

Background Art

[0002] Some communication devices compress an image from a camera that captures an image inside a train or the like according to a predetermined algorithm and transmit it to an external device. When such a communication device receives a request from an external device, it acquires an image from the camera, compresses the acquired image, and transmits it to the external device.

[0003] Conventionally, there has been a problem that it takes time for a communication device to transmit a compressed image after receiving a request from an external device.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In order to solve the above problems, a communication device and a communication method capable of quickly transmitting an image are provided.

Means for Solving the Problems

[0006] According to an embodiment, The vehicles that make up a train a communication device installed in is provided with a first communication unit, a second communication unit, a storage unit, and a processor. The first communication unit transmits and receives data to and from an external device installed on the ground. The second communication unit A first group of cameras that photograph users passing through a door formed on the first side of the vehicle, and a second group of cameras that photograph users passing through a door formed on the second side of the vehicle.The data is sent and received. The memory unit stores the data. The processor connects to the camera via the second communication unit using a predetermined protocol, acquires image data captured by the camera via the second communication unit, compresses the image data to generate a compressed image, stores the compressed image in the memory unit, and, via the first communication unit, Specify the group of cameras that capture the images to be acquired. When an acquisition command is received from the external device, The compressed image of the image data captured by the camera of the designated group The storage unit transmits the compressed image it stores to the external device. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a schematic diagram of the communication system according to the embodiment. [Figure 2] Figure 2 is a block diagram showing an example configuration of a communication system according to an embodiment. [Figure 3] Figure 3 is a sequence diagram showing an example of the operation of a communication system according to the embodiment. [Figure 4] Figure 4 is a flowchart showing an example of the operation of the gateway according to this embodiment. [Modes for carrying out the invention]

[0008] The embodiments will be described below with reference to the drawings. The communication system according to this embodiment transmits images captured by a camera to a server. In this case, the communication system transmits images captured by a camera installed in a train or other vehicle to a server located on the ground. That is, the communication system transmits images captured by a camera to the server in accordance with a request from the server located on the ground.

[0009] Figure 1 is a schematic diagram of a communication system 1 according to an embodiment. As shown in Figure 1, the communication system 1 consists of a server 20 and a vehicle 100, etc.

[0010] Vehicle 100 (mobile unit) is a vehicle that constitutes a train such as a train, Shinkansen, or monorail. Vehicle 100 is equipped with a gateway 10, a camera 60, and a door 101, etc. The gateway 10 and the camera 60 are connected in a communication manner.

[0011] Gateway 10 (communication device) acquires images captured by camera 60. Gateway 10 also transmits images captured by camera 60 to server 20 according to signals from server 20. Gateway 10 will be described in more detail later.

[0012] Door 101 is an entrance / exit to vehicle 100. In other words, door 101 is the door through which users boarding or alighting from vehicle 100 pass. Door 101 opens and closes according to the instructions of an operator such as a conductor.

[0013] Here, the door 101 consists of eight doors 101a to 101h. Doors 101a to 101d are formed on a predetermined surface (first surface) of the vehicle 100. Doors 101e to 101h are formed on a surface (second surface) opposite to the first surface.

[0014] Camera 60 photographs the interior of vehicle 100. Camera 60 transmits the captured images to gateway 10. Camera 60 consists of eight cameras 60a to 60h. Cameras 60a to 60h each photograph users passing through doors 101a to 101h. For example, cameras 60a to 60h are installed above doors 101a to 101h, respectively.

[0015] For example, camera 60 is composed of a CCD (charge coupled device) image sensor or a CMOS (complementary MOS) image sensor. For example, camera 60 captures VGA (Video Graphics Array) images.

[0016] Furthermore, the camera 60 may also be equipped with a light or the like to illuminate the shooting area. Further, the camera 60 may be configured to photograph the central portion of the vehicle 100. The number of cameras 60 or the photographing area is not limited to a specific configuration.

[0017] The server 20 (external device) manages the images photographed by the camera 60. Based on an operation by an operator or the like, the server 20 transmits an acquisition command for acquiring an image from the camera 60 to the gateway 10. The server 20 receives a response including the image from the camera 60 from the gateway 10. The server 20 displays the image included in the received response on a display unit or the like.

[0018] FIG. 2 is a block diagram showing a configuration example of the control system of the communication system 1. As shown in FIG. 2, the communication system 1 includes a gateway 10, a server 20, a camera 60, and the like. The server 20 and the camera 60 are as described above.

[0019] The gateway 10 includes a processor 11, a memory 12, an operation unit 13, a display unit 14, a first communication unit 15, a second communication unit 16, and the like. The processor 11, the memory 12, the operation unit 13, the display unit 14, the first communication unit 15, and the second communication unit 16 are communicably connected via a data bus or a predetermined interface or the like.

[0020] Note that, in addition to the configuration shown in FIG. 2, the gateway 10 may further include a configuration as required, or a specific configuration may be excluded from the gateway 10.

[0021] The processor 11 controls the overall operation of the gateway 10. For example, the processor 11 controls the camera 60. Further, the processor 11 transmits the image photographed by the camera 60 to the server 20 in accordance with the control from the server 20.

[0022] For example, the processor 11 is composed of a CPU, etc. Alternatively, the processor 11 may be composed of an ASIC (Application Specific Integrated Circuit), etc. Furthermore, the processor 11 may be composed of an FPGA (Field Programmable Gate Array), etc.

[0023] The memory 12 (storage unit) stores various types of data. For example, the memory 12 functions as ROM, RAM, and NVM. For example, memory 12 stores control programs and control data. The control programs and control data are pre-installed according to the specifications of gateway 10. For example, the control program is a program that supports the functions implemented by gateway 10.

[0024] Furthermore, memory 12 temporarily stores data being processed by the processor 11. Memory 12 may also store data necessary for executing the application program and the execution results of the application program.

[0025] Furthermore, the memory 12 includes a storage area 12a for storing image data (for example, VGA images) captured by the camera 60, and a storage area 12b for storing compressed images (for example, QVGA (Quarter VGA) images) obtained by compressing the image data.

[0026] The control unit 13 receives various operation inputs from the operator. The control unit 13 transmits a signal indicating the input operation to the processor 11. The control unit 13 consists of a keyboard, buttons, or a touch panel.

[0027] The display unit 14 displays information based on control from the processor 11. For example, the display unit 14 is composed of a lamp or a liquid crystal monitor. If the operation unit 13 is composed of a touch panel, the display unit 14 is composed of a liquid crystal monitor integrally formed with the operation unit 13.

[0028] The first communication unit 15 is an interface for sending and receiving data with the server 20. For example, the first communication unit 15 is an interface for connecting to the network to which the server 20 is connected. For example, the first communication unit 15 connects to the server 20 wirelessly.

[0029] The second communication unit 16 is an interface for sending and receiving data with the camera 60. For example, the second communication unit 16 connects to the camera 60 via a wired connection. For example, the second communication unit 16 is an interface that supports LAN (Local Area Network) connection or USB (Universal Serial Bus) connection.

[0030] Next, we will explain the functions that gateway 10 provides. The functions that gateway 10 provides are achieved when processor 11 executes a program stored in memory 12 or the like.

[0031] First, the processor 11 has the function of connecting to (joining) the camera 60.

[0032] When the processor 11 receives a predetermined command (connection command) from the server 20 via the first communication unit 15, it connects to the camera 60 using IGMP (Internet Group Management Protocol) (a predetermined protocol).

[0033] Furthermore, the processor 11 configures the ports to which each camera 60 will connect. The processor 11 connects to each camera 60 through a unique port. In other words, the processor 11 recognizes in advance the port to which each camera 60 will connect. The processor 11 connects to the camera 60 corresponding to the port through the port.

[0034] The processor 11 may also group the cameras 60. For example, the processor 11 may group the cameras 60 formed on the first surface (cameras 60a to d) as a first group. The processor 11 may also group the cameras 60 formed on the second surface (cameras 60e to h) as a second group.

[0035] Furthermore, the processor 11 has the function of acquiring image data captured by the camera 60.

[0036] When the processor 11 connects to the camera 60, it sends a command to the camera 60 instructing it to take a picture. The camera 60 takes a picture according to the command and sends the image data to the processor 11.

[0037] The processor 11 acquires image data from the camera 60. Once the image data is acquired, the processor 11 stores the acquired image data in the memory area 12a.

[0038] Once the acquired image data is stored in the memory area 12a, the processor 11 acquires image data from the camera 60 again. For example, the processor 11 acquires image data from the camera 60 at predetermined intervals (for example, 6 FPS).

[0039] The processor 11 stores the acquired image data back into the storage area 12a. The processor 11 may overwrite previously stored image data. Also, if the storage area 12a has stored a predetermined number of image data, the processor 11 may delete the oldest image data and store new image data in the storage area 12a.

[0040] Furthermore, the processor 11 has a function for compressing image data.

[0041] When the processor 11 acquires image data, it compresses the image data according to a predetermined algorithm and generates a compressed image. For example, the processor 11 generates a QVGA image as the compressed image.

[0042] The processor 11 may generate a compressed image by reducing the resolution of the image data. Alternatively, the processor 11 may generate a compressed image while maintaining the resolution of the image data. The method by which the processor 11 generates the compressed image is not limited to any particular method.

[0043] When a compressed image is generated, the processor 11 stores the generated compressed image in the memory area 12b.

[0044] Once the generated compressed image is stored in the memory area 12a, the processor 11 waits until new image data is acquired. When new RAW data is acquired, the processor 11 compresses the new image data and generates a compressed image.

[0045] The processor 11 stores the generated compressed image back into the storage area 12b. The processor 11 may overwrite previously stored compressed images. Also, if the storage area 12b has stored a predetermined number of compressed images, the processor 11 may delete the oldest compressed image and store a new compressed image in the storage area 12b.

[0046] Furthermore, the processor 11 has the function of transmitting images captured by the camera 60 to the server 20.

[0047] The processor 11 receives a command (acquisition command) from the server 20 to acquire an image captured by the camera 60 through the first communication unit 15.

[0048] The acquisition command specifies the images to be acquired from the images captured by each camera 60. That is, the acquisition command selects one or more cameras 60 from a group of cameras 60. For example, the acquisition command may specify the port number to which the camera 60 that captures the images to be acquired is connected. Alternatively, the acquisition command may specify a group of cameras 60 that capture the images to be acquired. Furthermore, the acquisition command may acquire each image captured by each camera 60.

[0049] Furthermore, the acquisition command specifies either image data or compressed images as the image to be acquired. Alternatively, the acquisition command may specify both image data and compressed images. Furthermore, the acquisition command may retrieve the most recent image or an older image.

[0050] The processor 11 acquires image data or a compressed image from storage area 12a or storage area 12b according to the acquisition command. The processor 11 sends a response containing the acquired image data or compressed image to the server 20 through the first communication unit 15.

[0051] The processor 11 maintains its connection with the camera 60 even after sending a response to the server 20.

[0052] First, the processor 11 has a function to disconnect (leave) the camera 60.

[0053] When the processor 11 receives a predetermined command (release command) from the server 20 via the first communication unit 15, it disconnects from the camera 60.

[0054] Next, we will describe an example of the operation of communication system 1. Figure 3 is a sequence diagram illustrating an example of the operation of communication system 1.

[0055] First, server 20 sends a connection command to gateway 10 (S11).

[0056] The processor 11 of the gateway 10 receives the connection command through the first communication unit 15. Upon receiving the connection command, the processor 11 connects to the camera 60 through the second communication unit 16 (S12).

[0057] When the processor 11 connects to the camera 60, the camera 60 sends the captured image data to the gateway 10 (S13).

[0058] The processor 11 of the gateway 10 acquires image data through the second communication unit 16. Once image data is acquired, the processor 11 stores the acquired image data in the storage area 12a (S14).

[0059] When the acquired image data is stored in the storage area 12a, the processor 11 compresses the acquired image data to generate a compressed image (S15). After generating the compressed image, the processor 11 stores the compressed image in the storage area 12b (S16).

[0060] Here, server 20 sends an acquisition command to gateway 10 to acquire the image (S17).

[0061] The processor 11 of the gateway 10 receives the acquisition command through the first communication unit 15. Upon receiving the acquisition command, the processor 11 sends a response including image data or compressed image to the server 20 in accordance with the acquisition command (S18).

[0062] At this point, server 20 sends a release command to gateway 10 (S19).

[0063] The processor 11 of the gateway 10 receives the release command through the first communication unit 15. Upon receiving the release command, the processor 11 disconnects the connection with the camera 60 in accordance with the release command (S20).

[0064] When the processor 11 disconnects from the camera 60, the communication system 1 terminates its operation.

[0065] Next, we will describe an example of how gateway 10 works. Figure 4 is a flowchart illustrating an example of the operation of gateway 10.

[0066] Here, we assume that the processor 11 of the gateway 10 is not connected to the camera 60.

[0067] First, the processor 11 determines whether it has received a connection command from the server 20 through the first communication unit 15 (S21). If it determines that it has not received a connection command (S21, NO), the processor 11 returns to S21.

[0068] If the processor determines that it has received a connection command (S21, YES), it connects to the camera 60 via the second communication unit 16 (S22). Once connected to the camera 60, the processor acquires image data captured by the camera 60 via the second communication unit 16 (S23).

[0069] When image data is acquired, the processor 11 stores the acquired compressed image in the storage area 12a (S24). After storing the acquired compressed image in the storage area 12a, the processor 11 compresses the acquired image data to generate a compressed image (S25).

[0070] When a compressed image is generated, the processor 11 stores the generated compressed image in the storage area 12b (S26). After storing the generated compressed image in the storage area 12b, the processor 11 determines whether it has received an acquisition command through the first communication unit 15 (S27).

[0071] If the processor 11 determines that it has received an acquisition command (S27, YES), it sends a response including image data or compressed image to the server 20 via the first communication unit 15 according to the received acquisition command (S28).

[0072] If it is determined that it has not received an acquisition command (S27, NO), or if it has sent a response containing image data or a compressed image to the server 20 (S28), the processor 11 determines whether it has received a release command through the first communication unit 15 (S29).

[0073] If it determines that it has not received a release command (S29, NO), processor 11 returns to S23.

[0074] If the processor determines that it has received a release command (S29, YES), it disconnects from the camera 60 (S30). After disconnecting from the camera 60, the processor 11 terminates its operation.

[0075] The processor 11 may execute S23 to S26 and S27 to S29 in parallel. In this case, when the processor 11 receives a release command (S29, YES), it stops S23 to S26.

[0076] Furthermore, after connecting to the camera 60 (S12, S22), the processor 11 may send a response to the server 20 via the first communication unit 15 indicating that it has connected to the camera 60.

[0077] Furthermore, after disconnecting from the camera (S30), the processor 11 may send a response to the server 20 via the first communication unit 15 indicating that it has disconnected from the camera 60.

[0078] The connection command may also specify an algorithm for compressing the image data. In this case, the processor 11 compresses the image data according to the algorithm specified by the connection command and generates a compressed image.

[0079] Furthermore, the connection command may also specify whether or not compression is required. If the connection command specifies that compression of the image data is not required, the processor 11 will not compress the image data. That is, the processor 11 will not execute S15 and S16 (S25 and S26).

[0080] Furthermore, while the connection between the gateway 10 and the camera 60 is maintained, the server 20 may send a command to the gateway 10 to change the algorithm for compressing the image data or whether compression is necessary. The processor 11 of the gateway 10 changes the algorithm for compressing the image data or whether compression is necessary in accordance with the command.

[0081] Furthermore, the gateway 10 or camera 60 may be installed in a location other than the vehicle 100. For example, the gateway 10 or camera 60 may be installed on a ship, aircraft, or building. The location where the gateway 10 or camera 60 is installed is not limited to a specific configuration.

[0082] As described above, the gateway acquires and compresses images before receiving a command from the server to acquire them. When the gateway receives the command from the server, it sends the pre-acquired or pre-compressed images to the server. As a result, the gateway can quickly send images in response to commands from the server.

[0083] Although several embodiments of the present invention have been described, these embodiments are presented as examples only. Therefore, it is not intended to limit the scope of the invention. These novel embodiments are It can be implemented in various other forms, and without departing from the spirit of the invention, various Omissions, substitutions, and modifications are permitted. These embodiments and their variations fall within the scope of the invention. It is included in the abstract and also within the scope of the invention described in the claims and its equivalents. . [Note 1] A communication device installed on a mobile device, A first communication unit that transmits and receives data with external devices installed on the ground, A second communication unit that transmits and receives data from the camera, A storage unit for storing data, The camera is connected via the second communication unit using a predetermined protocol. Through the second communication unit, the image data captured by the camera is acquired. After unpacking the aforementioned image data, recompress it as needed to generate a compressed image. The compressed image is stored in the storage unit, When the first communication unit receives an acquisition command from the external device, the storage unit transmits the compressed image stored in it to the external device. Processor and A communication device equipped with the following features. [Note 2] The acquisition command is a command for acquiring the image data or the compressed image, The aforementioned processor, The image data is stored in the storage unit, In accordance with the acquisition command, the storage unit transmits the image data or compressed image stored in it to the external device. The communication device described in Appendix 1. [Note 3] The processor acquires the image data at predetermined intervals through the second communication unit, compresses the image data to generate the compressed image, and stores the compressed image in the storage unit. The communication device described in Appendix 1. [Note 4] The aforementioned camera is composed of multiple cameras, The acquisition command selects one or more cameras from the multiple cameras, The processor transmits the compressed image corresponding to the camera selected by the acquisition command to the external device via the first communication unit. A communication device as described in any of the appendices 1 to 3. [Note 5] When the processor receives a connection command through the first communication unit, it connects to the camera. A communication device as described in any of the appendices 1 to 4. [Note 6] When the processor receives a release command through the first communication unit, it disconnects from the camera. A communication device as described in any of the appendices 1 to 5. [Note 7] The aforementioned predetermined protocol is IGMP. A communication device as described in any of the appendices 1 through 6. [Note 8] The aforementioned camera photographs the interior of the train cars. A communication device as described in any of the appendices 1 through 7. [Note 9] A communication method executed by a processor of a communication device installed on a mobile device, Connect to the camera using the specified protocol, The camera captures image data, The aforementioned image data is compressed to generate a compressed image. The compressed image is stored in the storage unit, When an acquisition command is received from an external device installed on the ground, the compressed image stored in the memory unit is transmitted to the external device. Communication method. [Explanation of Symbols]

[0084] 1...Communication system, 10...Gateway, 11...Processor, 12...Memory, 12a...Storage area, 12b...Storage area, 13...Operation unit, 14...Display unit, 15...First communication unit, 16...Second communication unit, 20...Server, 60 (60a to h)...Camera, 100...Vehicle, 101 (101a to h)...Door.

Claims

1. A communication device installed in a train, A first communication unit that transmits and receives data with an external device installed on the ground, A first group of cameras that photograph users passing through a door formed on the first side of the vehicle, and a second group of cameras that photograph users passing through a door formed on the second side of the vehicle, and a second communication unit that transmits and receives data from these cameras, A storage unit for storing data, The camera is connected via the second communication unit using a predetermined protocol. Through the second communication unit, the image data captured by the camera is acquired. The image data is stored in the storage unit, After unpacking the aforementioned image data, recompress it as needed to generate a compressed image. The compressed image is stored in the storage unit, When the first communication unit receives an acquisition command from the external device specifying a group of cameras that capture images to be acquired, it transmits the image data or compressed image of the image data captured by the cameras of the specified group, or the image data or compressed image stored in the storage unit, to the external device. Processor and A communication device equipped with the following features.

2. The acquisition command specifies the image data or the compressed image as the image to be acquired. The aforementioned processor, In accordance with the acquisition command, the storage unit transmits the image data or compressed image stored in it to the external device. The communication device according to claim 1.

3. The processor acquires the image data at predetermined intervals through the second communication unit, compresses the image data to generate the compressed image, and stores the compressed image in the storage unit. The communication device according to claim 1.

4. Each of the first group and the second group consists of a plurality of the cameras, The acquisition command specifies a group of cameras that capture images to be acquired, and selects multiple cameras from the specified group from among the multiple cameras. The processor transmits the image data or compressed image corresponding to the camera selected by the acquisition command to the external device via the first communication unit. A communication device according to any one of claims 1 to 3.

5. When the processor receives a connection command through the first communication unit, it connects to the camera. A communication device according to any one of claims 1 to 4.

6. When the processor receives a release command through the first communication unit, it disconnects from the camera. A communication device according to any one of claims 1 to 5.

7. The aforementioned predetermined protocol is IGMP. A communication device according to any one of claims 1 to 6.

8. A communication method executed by a processor of a communication device installed in a vehicle that makes up a train, Connected to a first group of cameras that photograph users passing through a door formed on the first side of the vehicle according to a predetermined protocol, and to a second group of cameras that photograph users passing through a door formed on the second side of the vehicle, The image data captured by the cameras of the first group and the cameras of the second group are acquired. The image data is stored in the storage unit, The aforementioned image data is compressed to generate a compressed image. The compressed image is stored in the storage unit, When an acquisition command specifying a group of cameras that capture images to be acquired is received from an external device installed on the ground, the image data or compressed image of the image data captured by the cameras of the specified group, which is stored in the storage unit, is transmitted to the external device. Communication method.

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