JP2004235692A - Video communication system and apparatus thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To transmit image information between video communication apparatuses without depending on the infrastructure. <P>SOLUTION: The video communication apparatus for transmitting image information directly to another video communication apparatus located around comprises an image divider 8 which divides an image file into k (equal to an integer not less than 2) division image data at a size enough to transmit in packets, generates image data information including the division number k, and gives a sequence number 1 to the image data information and sequence numbers 2 to (k+1) to the division image data, a transmission buffer 9 for temporarily storing the image data information and the division image data, and a communication processor 10 which generates image packets of the sequence number 1 to (k+1) from the image data information and the division image data and sends the image packets in burst transmission by denoting an initially transmitting packet as the sequence number 1. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image communication system configured by a plurality of image communication devices installed on a mobile body and transmitting image information between arbitrary image communication devices.
[0002]
[Prior art]
In a conventional image communication system, an image communication device installed on a mobile body such as a vehicle and a communication base station installed on the ground perform wireless communication and share image information (for example, see Patent Reference 1).
[0003]
[Patent Document 1]
JP-A-11-205782 (FIG. 1)
[0004]
[Problems to be solved by the invention]
However, in the above-described conventional image communication system, transmission of image information between vehicles in which the image communication device is installed depends on communication via a communication facility such as a communication station installed on the ground, that is, depends on infrastructure (Infrastructure). Communication. For this reason, in order to communicate with the surrounding vehicles that are arbitrarily encountered, it is necessary to periodically transmit the position and ID (identification data) of the own vehicle from the vehicle-mounted image communication device to the communication station. After acquiring and recognizing the position and ID of the partner vehicle located in the communication area from the communication station, it is necessary to wirelessly transmit image information from the host vehicle to the partner vehicle via the communication station. Since image data generally has a large data size, communication via such a communication facility has a problem that a load on a communication station is large.
[0005]
The present invention has been made to solve such a conventional problem, and an object of the present invention is to provide an image communication system capable of transmitting image information between arbitrary image communication devices without depending on infrastructure. Things.
[0006]
[Means for Solving the Problems]
The image communication system of the present invention includes:
An image communication system configured by a plurality of image communication devices each installed in a mobile body and transmitting image information directly between arbitrary image communication devices,
The first image communication device divides the image information into a plurality of image packets, and these image packets are burst-transmitted from the first image communication device to a second image communication device located therearound.
It is characterized by the following.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiment 1
FIG. 1 is a configuration diagram of the image communication device according to the first embodiment of the present invention. The image communication device according to the first embodiment includes a camera 1, an audio microphone 2, an inter-vehicle communication device (inter-vehicle communication terminal) 3, and a transmission / reception antenna 4, and is installed in a vehicle. The camera 1, the voice microphone 2, and the transmission / reception antenna 4 are connected to the inter-vehicle communication device 3 by wire or wireless, respectively.
[0008]
FIG. 2 is a block diagram of the inter-vehicle communication device 3. 2, the vehicle-to-vehicle communication device 3 includes a file conversion unit 5, an image storage disk 6, a main control processing unit 7, an image division unit 8, a transmission buffer unit 9, a communication processing unit 10, a peripheral vehicle management Unit 11, a receiving buffer unit 12, an image assembling unit 13, a GUI (Graphical User Interface) monitor 14, a message input unit 15, a personal computer connection interface 16, a memory card 17, and a GPS (Global Positioning System) device. 18 is provided.
[0009]
In the image communication system configured by the plurality of image communication apparatuses according to the first embodiment each installed in a vehicle, one image file is divided by a CSMA (Carrier Sense Multiple Access) method. By transmitting a plurality of image packets generated in a burst manner, one vehicle does not occupy the communication channel, shares the communication channel with the surrounding vehicles, and transmits images between arbitrary vehicles without passing through a communication station. Transmit files wirelessly.
[0010]
In the vehicle-to-vehicle communication device 3 and the following description, “vehicle-to-vehicle”, “vehicle-to-vehicle communication”, and “vehicle-to-vehicle image communication” mean direct communication between vehicles without passing through a communication facility such as a communication station.
[0011]
There are two usage modes of the inter-vehicle image communication according to the first embodiment, namely, usage for ensuring traveling safety (use for ensuring safety) and use for amusement (use for amusement). It is roughly divided into two.
[0012]
Specific examples of the use for ensuring safety include, for example, the following (a) to (e).
(A) When a large vehicle is traveling ahead and has poor visibility, a preceding vehicle (the large vehicle or a vehicle traveling in front of the large vehicle) transmits image information of the road ahead and the vehicle, and The vehicle traveling on receives the image information and secures the outlook.
(B) On a road with poor visibility (a mountain road with many curves, etc.), image information is transmitted from a preceding vehicle, and a vehicle traveling behind receives this image information and grasps the state of the road.
(C) The image information of the traffic congestion is transmitted from the vehicle near the end of the traffic congestion, and the vehicle traveling behind receives this image information and grasps the condition of the road.
(D) Image information of the accident site is transmitted from a vehicle passing through the accident site, and a vehicle traveling behind acquires this image information to grasp the condition of the road.
(E) From a vehicle passing through a dangerous place (vehicle accident, falling object, road loss, collapse, etc.), image information of the dangerous place is transmitted to notify the danger, and a vehicle traveling behind is Obtain image information to understand road conditions and avoid danger.
[0013]
Specific examples of the amusement use include, for example, the following (f) to (h).
(F) Between vehicles moving in a group, image information in which a comment is added to a scenery, a person, an animal, and the like is mutually transmitted and acquired, and exchanged like mail.
(G) An image such as a scenery overlooked by the preceding vehicle is transmitted from the following vehicle to the preceding vehicle.
(H) The vehicle moving in the group transmits image information for informing the delayed following vehicle of the meeting place.
[0014]
Further, the communication mode (communication type) of the inter-vehicle image communication according to the first embodiment is one-to-one communication (an image is transmitted from the vehicle A to the specific vehicle B, or the image is requested from the vehicle B to the specific vehicle A). An image is transmitted from the vehicle A to the specific vehicle B) and one-to-many communication (image is transmitted from the vehicle A to an unspecified number of vehicles).
[0015]
Further, as a special form of the one-to-one communication or the one-to-many communication, there is a relay communication for communicating between distant vehicles. For example, in the relay transmission by one-to-many communication, in the use example (e), image information of the dangerous place is transmitted from a vehicle passing through the dangerous place to an unspecified number of vehicles traveling behind. The vehicle transmitting and traveling behind receives this image information to avoid danger, and transmits this image information to an unspecified number of vehicles traveling further behind. In this way, by relaying the vehicle, it is possible to adapt to not only short-range communication but also long-range communication, and image information can be transmitted to a vehicle located outside the communicable area via the relay vehicle.
[0016]
[One-to-one communication part 1]
The procedure of one-to-one communication for transmitting an image from the vehicle A to the specific vehicle B will be described below.
[0017]
[Transmission procedure of vehicle A (one-to-one communication part 1)]
The user of the vehicle A operates the image communication device to acquire image information, and further attaches voice or text message data to the image information as necessary, and transmits the ID of the destination vehicle (the ID of the vehicle B). The vehicle B is specified based on the position information of the surrounding vehicles and the like, and the image transmission by one-to-one communication is selected. The image communication device of the vehicle A divides the image information to generate a plurality of image packets according to the above operation, and transmits the image packets to the vehicle B by one-to-one communication. When the vehicle B is located outside the communicable area of the vehicle A, the transmission procedure is the same as the procedure of the relay communication in the one-to-one communication.
[0018]
The image packet transmitted from the vehicle A is communication type information indicating one-to-one transmission, transmission source ID (ID of the vehicle A), position information of transmission source, transmission destination ID (ID of the vehicle B), transmission It is composed of the previous position information, the divided image information, the sequence number of the image division, and the like.
[0019]
For example, an image to be transmitted is captured by the camera 1 to obtain image information, or image information is obtained from the image storage disk 6 (a message can be attached before or after image acquisition), and image transmission is performed by the touch panel of the monitor 14. When the screen 21 is selected and the vehicle B displayed on the image transmission screen 21 is touched, the image packet of the acquired image information is transmitted to the vehicle B by one-to-one communication.
[0020]
[Reception procedure of specific vehicle B (one-to-one communication part 1)]
The image communication device of the vehicle B receives the image packet transmitted from the vehicle A based on the type information indicating the one-to-one transmission, the transmission destination ID (ID of the vehicle A), and the like, and receives the received image packet. And restores the image information and displays the image information.
[0021]
Alternatively, the image communication device of the vehicle B receives the image packet transmitted from the vehicle A based on the type information indicating the one-to-one transmission and the transmission destination ID (ID of the vehicle A), and receives the one-to-one transmission. Inform the user that the communication has been received (displaying the reception on the monitor 14, turning on the LED, notifying by voice, etc.). The user of the vehicle B selects whether to display the received image information. When the display permission is selected, the image communication device of the vehicle B restores the image information from the received image packet and displays the image information. Is possible after a lapse of a predetermined time from the selection of).
[0022]
[One-to-one communication part 2]
The procedure of one-to-one communication in which the vehicle B requests an image from the specific vehicle A and transmits the image from the vehicle A to the specific vehicle B will be described below.
[0023]
[Transmission procedure of vehicle B (one-to-one communication part 2)]
When the user of the vehicle B feels the necessity of the image information, the user operates the image communication device to specify the vehicle A suitable for the transmission source of the image information, and selects transmission of a packet requesting image transmission. The image communication device of the vehicle B transmits a packet requesting image transmission to the vehicle A according to the above operation.
[0024]
The packet requesting the image transmission includes communication type information indicating that the packet is a one-to-one communication and an image transmission request, a transmission source ID (ID of the vehicle B), position information of the transmission source, and a transmission destination ID (the vehicle ID). A), location information of the transmission destination, and, if necessary, image request contents (possible by attaching a voice or text message).
[0025]
For example, a communication option setting screen is selected by the touch panel of the monitor 14, an image transmission request is selected from the communication option setting screen, and then an image transmission screen 21 is selected by the touch panel, and the image transmission screen 21 is displayed on the image transmission screen 21. When vehicle A is touched, a packet requesting image transmission is transmitted to vehicle A.
[0026]
[Reception-transmission procedure of specific vehicle A (one-to-one communication part 2)]
The image communication device of the vehicle A receives the packet requesting image transmission transmitted from the vehicle B based on the transmission destination ID (ID of the vehicle A) and the like, and type information indicating an image transmission request, Image information is acquired based on the transmission source ID (ID of the vehicle B) and the content of the image request (acquisition can be performed at the same time as or after a predetermined period of reception of a packet requesting image transmission), and the image The packet is transmitted to the vehicle B.
[0027]
Alternatively, the image communication device of the vehicle A receives a packet requesting image transmission transmitted from the vehicle B based on the transmission destination ID (ID of the vehicle A) and the like, and indicates that the packet is an image transmission request. Based on the information, the transmission source ID (ID of the vehicle B), and the content of the image request, the user is notified that the image transmission request has been received, and the user is notified of the content of the image request. Can be displayed). The user of the vehicle A selects whether or not the requested image information can be transmitted (for example, a transmission permission / prohibition button can be displayed on the screen of the monitor 14). The image communication device of the vehicle A transmits a transmission refusal packet to the vehicle B when the transmission rejection is selected. When transmission permission is selected, image information is acquired (acquisition can be performed simultaneously with the selection of transmission permission or after a predetermined time), and an image packet of the image information is transmitted to the vehicle B.
[0028]
The image packet transmitted from the vehicle A includes type information indicating that the image packet is a one-to-one communication and a response image of an image transmission request, a transmission source ID (ID of the vehicle A), transmission source position information, and a request. It is composed of an original ID (ID of the vehicle B), position information of a request source, divided image information, a sequence number of image division, and the like.
[0029]
[Reception procedure of specific vehicle B (one-to-one communication part 2)]
The image communication device of the vehicle B is transmitted from the vehicle A based on type information indicating that the image is a one-to-one communication and a response image of an image transmission request, a request source ID (ID of the vehicle B), and the like. Receiving the received image packet, restoring the image information from the received image packet, and displaying the image information.
[0030]
[One-to-many communication 1]
The procedure of one-to-many communication for transmitting an image from vehicle A to an unspecified number of vehicles (including vehicle B) by broadcast will be described below.
[0031]
[Transmission procedure of vehicle A (one-to-many communication part 1)]
The user of the vehicle A operates the image communication device to acquire image information, further attaches voice or text message data to the image information as necessary, and selects image transmission by one-to-many communication. . The image communication device of the vehicle A divides the image information to generate a plurality of image packets according to the above operation, and transmits these image packets to an unspecified number of vehicles by one-to-many communication.
[0032]
The image packet transmitted from the vehicle A is type information indicating one-to-many communication, a transmission source ID (ID of the vehicle A), position information of the transmission source, divided image information, a sequence number of image division. And, if necessary, information indicating danger notification.
[0033]
For example, an image to be transmitted is captured by the camera 1 to acquire image information, or image information is acquired from the image storage disk 6 (a message can be attached before or after image acquisition), and the image is transmitted by the touch panel of the monitor 14. When the screen 21 is selected and the broadcast transmission button displayed on the image transmission screen 21 is touched, the image packet of the acquired image information is transmitted to an unspecified number of vehicles by one-to-many communication. When a danger notification button is provided in the image transmission screen 21 and the danger notification button is touched and information indicating danger notification is added to the above image packet to notify a danger to surrounding vehicles, It is valid.
[0034]
[Reception procedure of unspecified vehicle B (one-to-many communication part 1)]
The image communication device of the vehicle B receives the image packet broadcast-transmitted from the vehicle A based on the type information indicating the one-to-many transmission, the transmission destination ID (the ID of the vehicle A), and the like. The image information is restored from the packet, and the image information is displayed.
[0035]
Alternatively, the image communication device of the vehicle B receives the image packet broadcast-transmitted from the vehicle A based on the type information indicating the one-to-many transmission, the transmission destination ID (the ID of the vehicle A), and the like. The user is notified that the many-to-many communication has been received. The user of the vehicle B selects whether to display the received image information. When the display permission is selected, the image communication device of the vehicle B restores the image information from the received image packet and displays the image information. After a certain time). However, in the case where the received image information is image information of danger notification, the information is emphasized and notified, or the user is notified of the danger information without allowing the user to select whether or not to display the information. Display image information.
[0036]
[One-to-many communication part 2]
A one-to-many communication procedure for requesting an image from the vehicle B to an unspecified number of vehicles (including the vehicle A) and broadcasting the image from the vehicle A to the unspecified number of vehicles (including the vehicle B) will be described below. I do.
[0037]
[Transmission procedure of vehicle B (one-to-many communication part 2)]
When the user of the vehicle B feels the necessity of the image information, the user operates the image communication device to select transmission of a packet requesting image transmission. The image communication device of the vehicle B transmits a packet requesting image transmission to an unspecified number of vehicles according to the above operation.
[0038]
The packet requesting the image transmission includes communication type information indicating that the packet is a one-to-many communication and an image transmission request, a transmission source ID (ID of the vehicle B), transmission source position information, and, if necessary, It is composed of image request contents (possible by attaching voice or text message).
[0039]
[Reception-transmission procedure of unspecified vehicle A (one-to-many communication part 2)]
The image communication device of the vehicle A receives the packet requesting the image transmission transmitted from the vehicle B based on the communication type information or the like indicating the one-to-many communication, and indicates that the packet is the image transmission request. Image information is acquired based on the type information and the image request content, and an image packet of the image information is transmitted to an unspecified number of vehicles.
[0040]
Alternatively, the image communication device of the vehicle A receives a packet for requesting image transmission transmitted from the vehicle B based on communication type information indicating that the communication is one-to-many communication, and determines that the packet is an image transmission request. Is notified to the user that the image transmission request has been received and the image request content based on the type information indicating the image request and the image request content. The user of the vehicle A selects whether to transmit the requested image information. When transmission permission is selected, the image communication device of the vehicle A acquires image information and transmits an image packet of the image information to an unspecified number of vehicles.
[0041]
The image packet transmitted from the vehicle A includes type information indicating that the image packet is a one-to-many communication and a response image of an image transmission request, a transmission source ID (ID of the vehicle A), position information of the transmission source, and a request. It is composed of an original ID (ID of the vehicle B), position information of a request source, divided image information, a sequence number of image division, and the like. The transmission from the vehicle A in response to the image transmission request at this time is not limited to one-to-many communication, but may be one-to-one communication in which the vehicle B is a specific vehicle.
[0042]
[Reception procedure of unspecified vehicle B (one-to-many communication part 2)]
The image communication device of the vehicle B is transmitted from the vehicle A based on the type information indicating that the communication is a one-to-many communication and a response image of the image transmission request, the request source ID (the ID of the vehicle B), and the like. Receiving the received image packet, restoring the image information from the received image packet, and displaying the image information.
[0043]
[Relay communication in one-to-many communication]
The relay communication in which an image is broadcast-transmitted from the vehicle A to an unspecified number of vehicles (including the vehicle B), and the image is broadcast-transmitted from the vehicle B to the unspecified number of vehicles (including the vehicle C). The procedure will be described below.
[0044]
[Transmission procedure of vehicle A (relay communication in one-to-many communication)]
The user of the vehicle A operates the image communication device to acquire image information, and further attaches voice or text message data to the image information as necessary, and transmits the image by relay communication and one-to-many communication. Select The image communication device of the vehicle A divides the image information to generate a plurality of image packets according to the above operation, and transmits the image packets to an unspecified number of vehicles by one-to-many communication.
[0045]
The image packet transmitted from the vehicle A includes type information indicating relay communication, type information indicating one-to-many transmission, transmission source ID (ID of the vehicle A), transmission source position information, It is composed of image information, a sequence number of image division, and information indicating danger notification as required.
[0046]
[Reception-transmission procedure of unspecified vehicle B (relay communication in one-to-many communication)]
The image communication device of the vehicle B receives the image packet broadcast-transmitted from the vehicle A based on the type information indicating the one-to-many transmission, the transmission destination ID (the ID of the vehicle A), and the like. The image information is restored from the packet, and the image information is displayed.
[0047]
Alternatively, the image communication device of the vehicle B receives the image packet broadcast-transmitted from the vehicle A based on the type information indicating the one-to-many transmission, the transmission destination ID (the ID of the vehicle A), and the like. The user is notified that the many-to-many communication has been received. The user of the vehicle B selects whether to display the received image information. When the display permission is selected, the image communication device of the vehicle B restores the image information from the received image packet and displays the image information.
[0048]
At the same time, the image communication device of the vehicle B transmits the information from the vehicle A based on the type information indicating the relay communication, the type information indicating the one-to-many transmission, the destination ID (the ID of the vehicle A), and the like. The received image packet is relayed to an unspecified number of vehicles by one-to-many communication. At this time, if necessary, the user is notified that relay transmission is being performed.
[0049]
Alternatively, the image communication device of the vehicle B performs the one-to-many communication based on the type information indicating the relay communication, the type information indicating the one-to-many transmission, the destination ID (the ID of the vehicle A), and the like. Is notified to the user that the relay communication has been received. The user of the vehicle B selects whether or not to relay the received image information. When the relay transmission is selected, the image communication device of the vehicle B relays the image packet received from the vehicle A to an unspecified number of vehicles by one-to-many communication. After a certain time).
[0050]
The image packet relay-transmitted from the vehicle B includes type information indicating relay communication, type information indicating one-to-many transmission, source ID (ID of the vehicle A), position information of the source, relay source It is composed of an ID (ID of the vehicle B), position information of a relay source, divided image information, a sequence number of image division, information indicating danger notification, and the like.
[0051]
[Reception-transmission procedure of unspecified vehicle C (relay communication in one-to-many communication)]
The procedure in which the unspecified vehicle C receives and transmits the image packet relayed and transmitted from the vehicle B is the same as the reception-transmission procedure in the vehicle B. By repeating such relay communication, image information such as danger information can be transmitted to an unspecified number of vehicles that are not located in the communication area of the vehicle A.
[0052]
[Relay communication in one-to-one communication]
The procedure of the relay communication in which the image is transmitted from the vehicle A to the specific vehicle B by one-to-one communication, and the image is transmitted from the vehicle B to the specific vehicle C by the one-to-one communication when the image is received will be described below. .
[0053]
Each vehicle transmits the position information packet of the own vehicle by one-to-other communication separately from the image packet. When the transmission destination vehicle C is not located in the communication area, the image communication device of the transmission source vehicle A transmits the position information packet (ID of the vehicle C, (Consisting of position information and the like), the ID and position of the vehicle C can be recognized. However, if the image communication device of the vehicle A cannot receive the position information packet and cannot recognize the ID and the position of the vehicle C, the user of the vehicle A obtains the ID and the position information of the vehicle C separately in advance. Must be input to the image communication device.
[0054]
[Transmission procedure of vehicle A (relay communication in one-to-one communication)]
The user of the vehicle A operates the image communication device to acquire image information, further attaches voice or text message data to the image information as necessary, and transmits the ID of the destination vehicle (the ID of the vehicle C). The vehicle C is specified as the destination vehicle based on the position information of the surrounding vehicles and the like, and image transmission by one-to-one communication is selected. The image communication device of the vehicle A divides the image information to generate a plurality of image packets in accordance with the above operation, and based on the position information of the own vehicle and the position information of the destination vehicle (vehicle C). It is determined whether or not the vehicle C is located within the communication area. If the destination vehicle C is not located within the communication area, the transmission destination vehicle C is further determined based on position information of other surrounding vehicles. Is identified as a relay vehicle in the communication area closest to the relay vehicle, and the above image packet is transmitted to the relay vehicle B by one-to-one communication. Note that the transmission procedure when the transmission destination vehicle C is located in the communication area is the same as the procedure of the above-mentioned one-to-one communication.
[0055]
Alternatively, the user of the vehicle A operates the image communication device to acquire image information, further attaches voice or text message data to the image information as necessary, and transmits the ID of the destination vehicle (the vehicle C). ID), the vehicle C is specified as the destination vehicle based on the position information of the surrounding vehicles, and the image transmission by the relay communication and the one-to-one communication is selected. The image communication device of the vehicle A divides the image information according to the above operation to generate a plurality of image packets, and based on the position information of the own vehicle, the position information of the surrounding vehicles, etc. Vehicle B in the communication area closest to C is specified as a relay vehicle, and the above image packet is transmitted to relay vehicle B by one-to-one communication.
[0056]
The image packet transmitted from the vehicle A is type information indicating relay transmission, type information indicating one-to-one transmission, a transmission source ID (ID of the vehicle A), transmission source position information, transmission The destination ID (the ID of the vehicle C), the position information of the transmission destination, the relay vehicle destination ID (the ID of the vehicle B), the position information of the relay destination, the divided image information, the sequence number of the image division, and the like.
[0057]
[Reception-transmission procedure of relay vehicle B]
The image communication device of relay vehicle B also includes type information indicating relay transmission, type information indicating one-to-one transmission, relay vehicle destination ID (ID of vehicle B), relay destination position information, and the like. At this time, the image packet transmitted from the vehicle A is received, and it is recognized that the communication is the relay communication. Then, based on the position information of the own vehicle and the position information of the transmission destination vehicle (vehicle C), it is determined whether or not vehicle C is located in the communication area.
[0058]
If the destination vehicle C is located within the communication area, the image communication device of the relay vehicle B specifies the vehicle C as the destination vehicle, and transmits the image packet received from the vehicle A to the vehicle C by one-to-one communication. Relay transmission. At this time, the user is notified that relay transmission is in progress, if necessary. It is also possible to notify the user that the relay communication in the one-to-one communication has been received, and to perform the relay transmission when the user selects the relay transmission enabled.
[0059]
At this time, the image packet transmitted from the vehicle B is type information indicating relay transmission, type information indicating one-to-one transmission, transmission source ID (ID of the vehicle A), transmission source position information , Transmission destination ID (ID of vehicle C), transmission destination position information, relay source ID (vehicle B ID), relay source position information, divided image information, image division sequence number, and the like.
[0060]
If the destination vehicle C is not located in the communication area, the image communication device of the relay vehicle B also stores the position information of the own vehicle, the position information of the destination vehicle C, the position information of other surrounding vehicles, and the like. At this time, a vehicle in the communication area closest to the transmission destination vehicle C is specified as a relay vehicle, and the above image packet is transmitted to the relay vehicle by one-to-one communication. By repeating such relay communication, image information can be transmitted to the specific vehicle C which is not located in the communication area of the vehicle A.
[0061]
At this time, the image packet transmitted from the vehicle B is type information indicating relay transmission, type information indicating one-to-one transmission, transmission source ID (ID of the vehicle A), transmission source position information , Transmission destination ID (ID of vehicle C), transmission destination position information, relay source ID (vehicle B ID), relay source position information, relay destination ID (relay vehicle ID specified by vehicle B), relay It is composed of the previous position information, the divided image information, the sequence number of the image division, and the like.
[0062]
Next, the configuration and operation of the image communication device according to the first embodiment will be described with reference to FIGS.
[Camera 1]
A still image such as a landscape or a traffic jam ahead taken from the inside of the vehicle by the camera 1 is sent to the file conversion unit 5 of the inter-vehicle communication device 3.
[0063]
[File Converter 5]
The file conversion unit 5 converts the photographed image into an image file such as a JPEG file under the control of the main control processing unit 7, and sends the image file to the image storage disk 6, the image division unit 8, and the monitor 14.
[0064]
[Audio Microphone 2]
When attaching a voice message to a still image captured and transmitted by the camera 1, the voice message is input to the voice microphone 2. This voice message is sent to the message input unit 15 of the inter-vehicle communication device 3.
[0065]
When a text message is attached to a still image captured and transmitted by the camera 1, the text message is input by operating the touch panel or the operation keys 19 of the monitor 14. This text message is also sent to the message input unit 15.
[0066]
[Message input unit 15]
The message input unit 15 converts the input attached message (voice message or character message) into attached message data (voice data or character data), and sends the attached message data to the transmission buffer unit 9.
[0067]
[Image recording disk 6]
The image recording disk 6 records an image file photographed from the file converting unit 5 and an image file received from the image assembling unit 13 under the control of the main control processing unit 7, and stores these image files in the monitor 14. To the personal computer connection interface 16 and the memory card 17, and also sends the photographed image file to the image dividing unit 8.
[0068]
That is, when the captured image is not transmitted immediately, the image file is recorded on the image recording disk 6, read out from the image recording disk 6 at the time of image transmission, and sent to the image dividing unit 8.
[0069]
When displaying a photographed image or a received image, the image file output from the file conversion unit 5, the received image file output from the image assembling unit 13, or the image file recorded on the image recording disk 6. The captured or received image file is sent to the monitor 14.
[0070]
When the image file recorded on the image recording disk 6 is taken out from the inter-vehicle communication device 3, the image data is sent to the personal computer connection interface 16 or the memory card 17, and the inter-vehicle communication device 3 (if necessary, from the vehicle after the operation is completed). The recording device is connected to the recording device in a personal computer connected to the portable device or the portable communication device, or is detached from the inter-vehicle communication device 3 and is recorded on the portable and movable memory card 17.
[0071]
[Monitor 14]
The monitor 14 has a touch panel structure, displays a screen 20 for displaying a still image captured by the camera 1 or a still image received and reproduced, and displays and broadcasts the vehicle and its surrounding vehicles centering on the vehicle. An image transmission screen 21 displaying buttons, a communication option selection screen, and the like can be switched and displayed by the touch panel of the monitor 14 or the operation keys 19.
[0072]
On the image transmission screen 21, the user selects one-to-many communication or one-to-one communication. When one-to-many communication is selected, a broadcast transmission button is touched. When one-to-one communication is selected, a vehicle that is a destination among the surrounding vehicles is touched. In the communication option setting screen, the user sets a request for relay communication, image transmission, and the like.
[0073]
To transmit and receive an image file as it is in one image packet, the packet size becomes too large. Therefore, the image communication apparatus according to the first embodiment divides an image file and generates a plurality of image packets from each of the divided image data so that the image packet can be transmitted and received. Send and receive packets. Further, in the image communication device according to the first embodiment, a plurality of vehicles can communicate by sharing a channel by burst transmitting the series of image packets by the CSMA method.
[0074]
The transmitted and received packets include an image packet (a packet transmitting a divided image file), an Ack packet (reception completion packet), a Nack packet (retransmission request packet), and a GPS information packet (recognizing the position of the own vehicle to a nearby vehicle). And a packet for requesting image transmission, and the like. The communication processing unit 10 processes such packet communication.
[0075]
[Image division unit 8]
The image division unit 8 divides one input image file into a plurality of pieces of data of a size that allows packet communication by the CSMA scheme under the control of the main control processing unit 7, and also divides image data information on the image division processing. The generated image data information and the divided image data are sent to the transmission buffer unit 9 with a sequence number attached thereto.
[0076]
[Transmission buffer unit 9]
The transmission buffer unit 9 temporarily stores the image data information and the divided image data from the image division unit 8 and the attached message data from the message input unit 15 for each transmission image file under the control of the main control processing unit 7. Are sent to the communication processing unit 10 in the order of the sequence numbers.
[0077]
[GPS device 18]
The GPS device 18 receives GPS information (position information including information on latitude, longitude, azimuth, speed, and the like) of the own vehicle and sends the information to the communication processing unit 10.
[0078]
[Communication processing unit 10]
The communication processing unit 10 sequentially generates a plurality of image packets for one transmission image file under the control of the main control processing unit 7, and transmits these image packets from the transmission / reception antenna 4 in burst.
[0079]
Each of the above image packets includes image data information or divided image data (attached message data depending on the image packet), sequence number, communication type information, error control method information, source ID (own vehicle ID), source , The destination ID, the destination GPS information, the relay vehicle destination ID, the relay destination GPS information, the relay vehicle source ID, the relay source GPS information, and the like. However, ID and GPS information differ depending on the selected communication type.
[0080]
Further, the communication processing unit 10 sequentially receives a plurality of image packets for one image file burst-transmitted from the surrounding vehicle from the transmission / reception antenna 4 according to the control of the main control processing unit 7, and from the received image packets, Separates image data information, divided image data, attached message data, sequence number, communication type information, error control method information, source ID, source GPS information, etc., and separates image data information, divided image data, and attached message data. , A sequence number, etc., to the reception buffer unit 12.
[0081]
Further, the communication processing unit 10 periodically generates a GPS information packet of the own vehicle under the control of the main control processing unit 7 and periodically broadcasts the GPS information packet from the transmitting / receiving antenna 4.
[0082]
The GPS information packet of the host vehicle includes the ID of the host vehicle, GPS information from the GPS device 18, and the like.
[0083]
In addition, the communication processing unit 10 periodically receives the GPS information packets of the peripheral vehicles broadcast periodically transmitted from each of the peripheral vehicles under the control of the main control processing unit 7, and receives the GPS information packets of the peripheral vehicles from the GPS information packets. The ID and the GPS information are separated and sent to the peripheral vehicle management unit 11. The ID of the source vehicle separated from the image packet, the GPS information of the source, and the like are also sent to the peripheral vehicle management unit 11 as necessary.
[0084]
As described above, by periodically receiving the GPS information packet of the surrounding vehicle, the image communication device of the own vehicle can recognize the surrounding vehicle, and the one-to-one communication becomes possible.
[0085]
Further, under the control of the main control processing unit 7, the communication processing unit 10 generates a packet requesting image transmission, and transmits the packet requesting image transmission from the transmitting / receiving antenna 4.
[0086]
The packet for requesting image transmission is communication type information indicating an image transmission request, transmission source ID (request source ID), transmission source position information, transmission destination ID (request destination ID), transmission destination position It consists of information, image request contents and the like.
[0087]
[Transmit / receive antenna 4]
The transmission / reception antenna 4 transmits the packet generated by the communication processing unit 10 and receives the packet transmitted from the image communication device of the surrounding vehicle and sends the packet to the communication processing unit 10 because the communication partner is the surrounding vehicle. In addition, it is desirable that the antenna is an omnidirectional antenna.
[0088]
[Peripheral vehicle management unit 11]
The peripheral vehicle management unit 11 manages the situation of the peripheral vehicle based on the GPS information of the own vehicle and the GPS information of the peripheral vehicle from the communication processing unit 10 under the control of the main control processing unit 7.
[0089]
For example, in the case of one-to-one communication, the peripheral vehicle management unit 11 determines the relative speed based on the speed information of the own vehicle included in the GPS information of the vehicle and the speed information of the communication partner included in the GPS information of the communication partner. Ask for.
[0090]
In one-to-one communication, as the relative speed between the own vehicle and the destination vehicle (communication partner) increases, the communicable time becomes shorter (since the communication partner moves out of the communication area in a short time). It is desirable to set the transmission priority and the number of (maximum) repeated transmissions of the same packet according to the relative speed with the communication partner.
[0091]
The relative speed with respect to the communication partner determined by the peripheral vehicle management unit 11 is sent to the transmission processing unit 10. When the relative speed is high, the transmission processing unit 10 sets a higher transmission priority and / or reduces the (maximum) number of repeated transmissions of the same packet so that transmission is completed earlier. Further, when the relative speed is low, the transmission processing unit 10 lowers the transmission priority and / or increases the (maximum) number of repeated transmissions of the same packet so that transmission can be performed reliably. This makes it possible to improve communication quality.
[0092]
In addition, for example, the peripheral vehicle management unit 11 obtains the number of communicable peripheral vehicles (peripheral vehicles located in the communication area). The number of peripheral vehicles with which communication is possible is notified to the driver by voice.
[0093]
[Reception buffer unit 12]
Under the control of the main control processing unit 7, the reception buffer unit 12 temporarily stores the image data information, the divided image data, and the attached message data from the communication processing unit 10 for each transmission source ID, The image data and the attached message data are sent to the image assembling unit 13 in sequence number order.
[0094]
Since image packets transmitted from a plurality of vehicles may be received at the same time, the reception buffer unit 12 is divided into several parts so that divided image data and the like can be temporarily stored for each vehicle ID. Further, since it is necessary to simultaneously receive image packets transmitted from a plurality of vehicles and temporarily store them in the reception buffer unit 12 for each vehicle ID, each image packet includes a transmission source ID and a sequence number. It is necessary to put information. That is, the divided image data and the like of the received image packet are classified by the transmission source ID and temporarily stored in the reception buffer unit 12.
[0095]
When all data (image data information, all divided image data, and attached message data) for one image file are sent from the communication processing unit 10, the reception buffer unit 12 sends the data to the image assembling unit 13. When all the data for one image file has been sent to the image assembling unit 13 sequentially, the data in the reception buffer unit 12 for that image file is deleted.
[0096]
[Image assembling unit 13]
The image assembling unit 13 assembles a plurality of divided image data sequentially input from the reception buffer unit 12 into an original image file according to the control of the main control processing unit 7 and reproduces the original image file. The data is sent to the monitor 14 and / or the image recording disk 6 together with the data.
[0097]
FIG. 3 is a diagram for explaining the operation of the image division unit 8 and the transmission buffer unit 9. In FIG. 3, each of a still image file 1 and a still image file 2 is a file generated by converting a still image captured by the camera 1 by the file conversion unit 5, and the file conversion unit 5 or the image storage disk. 8 is a file input to the image division unit 8.
[0098]
First, when the still image file 1 is input, the image dividing unit 8 divides the still image file 1. When the number of divisions of the still image file 1 is k (k is an integer equal to or greater than 2), the image dividing unit 8 divides the still image file 1 into k and sets image data information on the still image file 1 Generate Then, a sequence number 1 is assigned to the image data information, and a sequence number 2 to a sequence number (k + 1) are assigned to each of the k divided image data.
[0099]
The (k + 1) pieces of data for the still image file 1 are sequentially transmitted from the image dividing unit 8 to the transmission buffer unit 9, temporarily stored in the transmission buffer unit 9, and further sequentially transmitted from the transmission buffer unit 9 to the communication processing unit 10. Then, image packets are generated and transmitted in order from the data of sequence number 1.
[0100]
When the still image file 2 is input, the image dividing unit 8 divides the still image file 2 in the same manner as the still image file 1. When the number of divisions of the still image file 2 is k ′ (k ′ is an integer of 2 or more), the image dividing unit 8 divides the still image file 2 into k ′ and Generate image data information. Then, a sequence number 1 is assigned to the image data information, and a sequence number 2 to a sequence number (k ′ + 1) are assigned to each of the k ′ divided image data.
[0101]
The (k ′ + 1) data of the still image file 2 is also sequentially transmitted from the image dividing unit 8 to the transmission buffer unit 9, temporarily stored in the transmission buffer unit 9, and further transmitted from the transmission buffer unit 9 to the communication processing unit 10. The image packets are sequentially transmitted, and image packets are generated and transmitted in order from the data of sequence number 1.
[0102]
As described above, the reason why the sequence number is added to the data generated by the image dividing unit 8 is that the receiving side recognizes the image packet that could not be received and can send a retransmission request to the transmission source. This is because the image data can be assembled into one image file and reproduced.
[0103]
The image data information includes the number of divided image data, the file size of a still image file, and the like. By assigning a sequence number 1 to this image data information and transmitting the image packet of this image data information first, the receiving side can start from the first received image packet and reduce the number of divided image data ( The number of image packets), the file size, and the like can be recognized, and it is possible to transmit still image files having different file sizes by packet transmission.
[0104]
In the case of one-to-many communication, the transmission buffer unit 9 deletes all data for one image file after completing transmission of all image packets for one image file. Further, in the case of one-to-one communication, when the communication processing unit 10 receives an Ack packet from a transmission destination and receives an Ack signal, the transmission buffer unit 9 transmits data corresponding to the Ack packet (for the image file). All data or any one of the data is erased. However, if the communication processing unit 10 cannot receive the Ack packet and a timeout signal is input (in the case of timeout) even after the specified time has elapsed after the end of the transmission, even if the communication is one-to-one communication, To delete. Therefore, the transmission buffer unit 9 only needs to have a capacity and a configuration capable of storing data of several image files.
[0105]
FIG. 4 is a functional block diagram of the communication processing unit 10, and is a block diagram mainly explaining a function of transmitting and receiving image packets. 4, the same components as those in FIG. 1 are denoted by the same reference numerals.
[0106]
4, the communication processing unit 10 includes a wireless transmission unit 101, a wireless reception unit 102, a transmission packet data generation unit 106, a packet assembler unit 107, a transmission control unit 108, a D / A conversion unit 109, Carrier sense section 110 (including idle / busy determination section 111 and random time setting section 112), reception power measurement section 113, A / D conversion section 114, packet deassembler section 115, error control section 123 (error A detection unit 116, an error control method selection unit 117, an error control method 1 (best effort type) processing unit 118, an error control method 2 (guarantee type) processing unit 119, an error control method 3 (guarantee type) processing unit 120, An error packet recording unit 121 and a retransmission request unit 122).
[0107]
[Transmission packet data generation unit 106]
The transmission packet data generation unit 106 arranges a plurality of data to be transmitted in one packet into one data sequence, and sends the data sequence (transmission data sequence) to the packet assembler unit 107.
[0108]
For example, at the time of one-to-one communication of image packets, the own vehicle ID (source ID) 104, the other vehicle ID (destination ID) 105, communication type information (in this case, information indicating one-to-one communication), It is composed of packet type information (in this case, information indicating that the packet is an image packet), data input from the transmission buffer unit 9, sequence number, error control method information, GPS information of the own vehicle, GPS information of the other vehicle, and the like. The generated image data sequence is generated.
[0109]
When relaying image packets by one-to-many communication, the own vehicle ID (source ID) 104, communication type information (in this case, information indicating that the communication is relay communication by one-to-many communication), and packet type An image data sequence composed of information (in this case, information indicating that the packet is an image packet), data input from the transmission buffer unit 9, a sequence number, GPS information of the own vehicle, and the like is generated.
[0110]
When transmitting a GPS packet, the own vehicle ID 104, communication type information (in this case, information indicating one-to-many communication), packet type information (in this case, information indicating a GPS packet), A data string composed of GPS information and the like is generated.
[0111]
Also, at the time of one-to-one communication of the image transmission request packet, the own vehicle ID 104, the other vehicle ID 105, communication type information (in this case, information indicating that the communication is relay communication in one-to-one communication), and packet type information (in this case, A data string composed of an image transmission request packet, the contents of the image request, the GPS information of the own vehicle, the GPS information of the other vehicle, and the like is generated.
[0112]
When the Ack packet is returned, the own vehicle ID 104, the other vehicle ID 105, the communication type information (in this case, information indicating one-to-one communication), and the packet type information (in this case, information indicating that the packet is an Ack packet) ), Sequence number (only for error control method 2), error control method information (in this case, information on which of error control method 2 and error control method 3) GPS information of own vehicle, GPS of partner vehicle A data string composed of information and the like is generated.
[0113]
When the Nack packet is returned, the own vehicle ID 104, the other vehicle ID 105, the communication type information (in this case, information indicating one-to-one communication), and the packet type information (in this case, information indicating that the packet is a Nack packet) ), Sequence number (only for error control method 3), error control method information (in this case, information on which of error control method 2 or error control method 3), GPS information of own vehicle, A data string composed of GPS information and the like is generated.
[0114]
[Packet Assembler 107]
The packet assembler unit 107 assembles the input transmission data sequence into a packet, and sends the packet (transmission packet) to the transmission control unit 108.
[0115]
[Transmission control unit 108]
When a transmission packet is input, transmission control section 108 transmits a transmission request signal to random time setting section 112 of carrier sense section 110 for each transmission cycle T of inter-vehicle communication device 3. Then, when the transmission start signal is input from carrier sense section 110 of carrier sense section 110, transmission control section 108 sends the transmission packet to D / A converter 109.
[0116]
[D / A conversion unit 109]
The D / A converter 109 converts the digital signal of the input transmission packet into an analog signal, and sends the transmission packet of the analog signal to the wireless transmitter 101 via an LPF (low-pass filter).
[0117]
[Wireless Transmitter 101]
The wireless transmission unit 101 modulates an input analog signal transmission packet into an RF signal and transmits the RF signal from the transmission / reception antenna 4.
[0118]
[Wireless receiver 102]
Radio receiving section 102 demodulates the RF signal received by transmitting / receiving antenna 4 and sends the demodulated analog signal (received analog signal) to received power measuring section 113 and A / D converter 114. The received RF signal includes a packet (received packet) such as an Ack packet transmitted from the surrounding vehicle and received by the transmitting / receiving antenna 4.
[0119]
[Received power measurement unit 113]
Received power measuring section 113 measures the received power of the received RF signal from the input received analog signal, and transmits information of the measured received power (received power information) to idle / busy determining section 111 of carrier sense section 110 and error control. This is sent to the error control scheme selection section 117 of the section 123.
[0120]
[Carrier sense unit 110]
In carrier sense section 110, when a transmission request signal is input from transmission control section 108, random time setting section 112 transmits a determination request signal to idle / busy determination section 111 after a lapse of a random time set therein. send.
[0121]
When the determination request signal signal is input from the random time setting unit 112, the idle / busy determination unit 111 determines whether the communication channel is idle or busy based on the reception power information input from the reception power measurement unit 13. (Carrier sense).
[0122]
Then, if the channel is idle due to the carrier sense described above, the idle / busy determining section 111 immediately sends a transmission start signal to the transmission control section 108 and the error control scheme 2 processing section 119 of the error control section 123.
[0123]
If the channel is busy due to the above carrier sense, idle / busy determining section 111 sends random time setting request signal to random time setting section 112 to set a random time again.
[0124]
When the random time setting request signal is input, the random time setting unit 112 sets the random time again, and after the random time elapses, sends the determination request signal to the idle / busy determining unit 111 again.
[0125]
When the determination request signal signal is input again from the random time setting unit 112, the idle / busy determination unit 111 performs the carrier sense again.
[0126]
Then, if the channel is idle due to the above carrier sense again, idle / busy determination section 111 immediately sends a transmission start signal to transmission control section 108 and error control scheme 2 processing section 119 of error control section 123.
[0127]
[A / D conversion unit 114]
The A / D converter 114 converts the input received analog signal into a digital signal, and sends the digital signal (received digital signal) to the packet deassembler 115.
[0128]
[Packet Deassembler 115]
The packet deassembler unit 115 separates a received packet from an input received digital signal, further decomposes the received packet, separates a data string transmitted in the received packet, and converts the data string (received data string). To the error detection unit 116.
[0129]
[Error detection unit 116]
Error detection section 116 performs error detection processing on the input received data sequence to detect whether or not there is a reception error in the received data sequence (a received packet that has transmitted the received data sequence). (Error detection information) together with the input received data sequence, the error control scheme selection section 117, error control scheme 1 processing section 118, error control scheme 2 processing section 119, and error control scheme 3 of the error control section 123. Send to processing unit 120.
[0130]
[Error control unit 123]
The error control unit 123 selects an error control method 1 (best effort type), an error control method 2 (guarantee type), or an error control method 3 (guarantee type) or an error control method selected by the user. The transmission and reception of packets are controlled according to the method.
[0131]
[Error control method 1]
The error control method 1 is an error control method used for one-to-many communication in which a packet is transmitted to an unspecified number of communication partners, and an Ack packet (reception completion packet) and a Nack packet (retransmission request) are transmitted from the receiving side to the transmitting side. An error that increases the communication quality by transmitting the same packet a plurality of times (l (l, l is an integer of 2 or more)) or m (m is an integer of 2 or more) times on the transmission side without sending the packet). This is a control method. That is, the error control method 1 is a continuous transmission method for transmitting the same packet a plurality of times.
[0132]
On the other hand, the error control methods 2 and 3 are error control methods used for one-to-one communication for transmitting a packet to a specific communication partner.
[0133]
[Error control method 2]
In the error control method 2, the transmitting side transmits the same packet at a maximum of l (ell) times or m times until the Ack packet can be received, and the receiving side returns the Ack packet to the transmitting side immediately after the packet is correctly received. This is an error control method.
[0134]
[Error control method 3]
In the error control system 3, the transmitting side transmits a series of plural packets such as a plurality of image packets for one image file a plurality of times, respectively, and the receiving side transmits an Ack packet or a Nack packet for each of the series of plural packets. This is an error control method for sending back to the transmission side. The receiving side returns an Ack packet when all of the series of packets can be received, and returns a Nack packet when any of the series of packets cannot be received. Therefore, the third error control method is a combination method of a continuous transmission method for transmitting the same packet a plurality of times and a retransmission method.
[0135]
[Error control method selection unit 117]
The error control scheme selection section 117 includes an error control scheme 1 (error control scheme 1 processing section 118), an error control scheme 2 (error control scheme 2 processing section 119), or an error control scheme 3 (error control scheme 3 processing section 120). Select
[0136]
At the time of packet transmission, the error control scheme selection unit 117 performs error control based on the communication type and communication channel status (reception power information, error detection information, Ack packet reception status, and the like) selected by the user. Select a method.
[0137]
At the time of packet reception, error control scheme selection section 117 selects an error control scheme according to communication type information, packet type information, error control scheme information, and the like included in the received packet.
[0138]
Note that the transmitting side includes error control method information (information on which error control method among error control method 1, error control method 2, and error control method 3) in the image packet of sequence number 1 by including the error control method information. On the receiving side, the error control method can be recognized by the first received image packet for one image file.
[0139]
However, the communication type information (information on whether the communication is one-to-one communication, one-to-many communication, one-to-one communication, or one-to-many communication relay communication) is also included in the image packet with the sequence number “1”. In the point-to-multipoint communication, the error control method is 1, and in the point-to-point communication, the error control method 2 or the error control method 3 is used, so that the error control method information is unnecessary in the point-to-multipoint communication. The control method information is substantially information on which of the error control method 2 and the error control method 3. In the case of one-to-one communication of an image transmission request packet, since the error control method 2 is used, Also in this case, error control method information is unnecessary.
[0140]
[Error control method 1 processing unit 118]
In the one-to-many communication of image packets, the error control method 1 processing unit 118 selected on the transmission side transmits each of a plurality of image packets for one image file 1 (L) times by the transmission packet generation unit 106 or the like. , And complete the transmission.
[0141]
The error control method 1 processing unit 118 selected on the receiving side recognizes whether or not the input image data sequence is a correctly received image data sequence based on the error detection information. For the image data string that has been correctly received by any of the transmissions, the image data information, the divided image data, and the attached message data are sent to the reception buffer unit 12 together with their sequence numbers.
[0142]
Then, the error control method 1 processing unit 118 selected on the receiving side completes the receiving process after processing the image data sequence of the image packet of the last sequence number for the image file. Since the image data information is transmitted first by the image packet having the sequence number 1, the receiving side can recognize the final sequence number from the image data information.
[0143]
In the point-to-multipoint communication of the image transmission request packet, the error control method 1 processing unit 118 selected on the transmission side causes the transmission packet generation unit 106 and the like to transmit the image transmission request packet l (L) times and transmits Complete.
[0144]
The error control method 1 processing unit 118 selected on the receiving side recognizes whether or not the input image transmission request data sequence is an image transmission request data sequence that has been correctly received, based on the error detection information, and performs correct reception. If so, the reception of the image transmission request packet is completed.
[0145]
[Error control system 2 processing unit 119]
In the one-to-one communication of the image packet or the image transmission request packet, the error control method 2 processing unit 119 selected on the transmission side causes the transmission packet generation unit 106 and the like to first transmit the packet once. If the Ack packet can be received within a predetermined time after the transmission start signal is input from the idle / busy determination unit 111 for the first transmission, the transmission of the packet is completed. If an Ack packet cannot be received within the above-mentioned predetermined time (in the case of a timeout), the retransmission request unit 122 sends a transmission retransmission signal to the transmission packet data generation unit 106, and the packet is retransmitted. (The packet is transmitted for the second time).
[0146]
The error control method 2 processing unit 119 selected on the transmitting side sets the default value of the maximum number of times of transmission of the same packet to l (ell), and transmits the same packet up to l (ell) times if an Ack packet cannot be received. However, if the Ack packet cannot be received even after 1 (ell) transmissions, the transmission of the packet is abandoned.
[0147]
The error control method 2 processing unit 119 selected on the receiving side recognizes whether or not the input data sequence is a correctly received data sequence based on the error detection information. If the packet has been correctly received, the transmission packet generator 106 or the like immediately returns an Ack packet. In the case of the image data sequence, the image data information, the divided image data, and the attached message data of the image data sequence that has been correctly received are sent to the reception buffer unit 12 together with the sequence number.
[0148]
[Error control method 3 processing unit 120]
In the one-to-one communication of a plurality of image packets for one image file, the error control method 3 processing unit 120 selected on the transmission side uses the transmission packet generation unit 106 or the like to convert each of the image packets to 1 (L). Send each time.
[0149]
Then, the error control method 3 processing unit 120 selected on the transmission side transmits the image packet of the final sequence number for the image file, and then completes the transmission for the image file when the Ack packet is received. .
[0150]
Further, the error control method 3 processing unit 120 selected on the transmission side transmits the image packet having the final sequence number for the image file, and when the Nack packet is received, the sequence number returned by the Nack packet. To the retransmission requesting unit 122, and further from the retransmission requesting unit 122 to the transmission packet data generation unit 106 to transmit the above-mentioned sequence number and the retransmission signal at the time of transmission. To resend.
[0151]
Then, the error control method 3 processing unit 120 selected on the transmitting side retransmits in response to the Nack packet, and then completes transmission of the image file when the Ack packet is received. When the Nack packet is re-received after being retransmitted in response to the Nack packet, the image packet having the sequence number returned by the Nack packet is transmitted again.
[0152]
The error control method 3 processing unit 120 selected on the transmitting side sets the default value of the maximum number of transmissions (the total number of the first transmission and the retransmission according to the Nack packet) of the image file to n (n is 2 or more). If an Ack packet cannot be received, an image packet for the image file is transmitted n times at the maximum.
[0153]
The error control method 3 processing unit 120 selected on the receiving side recognizes, based on the error detection information, whether or not the image data sequence input from the error detection unit 116 is a correctly received data sequence. Then, for the image data sequence that has been correctly received in any of the above (l) transmissions, the image data information, the divided image data, and the attached message data are sent to the reception buffer unit 12 together with their sequence numbers. In addition, the sequence number of the image data sequence that could not be correctly received even after the l (L) transmissions is recorded in the error packet recording unit 121.
[0154]
Then, after processing the image packet of the last sequence number for the image file, the error control method 3 processing unit 120 selected on the receiving side, if all the image packets can be correctly received, the transmission packet generation unit 106 Then, an Ack packet is returned, and the reception of the image file is completed. Since the image data information is transmitted first by the image packet of the sequence number 1, the receiving side can recognize the final sequence number from the image data information.
[0155]
If the error control method 3 processing unit 120 selected on the receiving side processes the image packet of the last sequence number for the image file and fails to receive any of the image packets correctly, The sequence number recorded in the recording unit 121 is sent to the retransmission request unit 122, and the sequence number and the retransmission signal at reception are sent from the retransmission request unit 122 to the transmission packet generation unit 106. Then, a Nack packet including the above sequence number is returned.
[0156]
Then, the error control method 3 processing unit 120 selected on the receiving side, if all the image packets retransmitted according to the Nack packet can be correctly received, transmits the Ack packet by the transmission packet generation unit 106 or the like. A reply is received, and the reception of the image file is completed. If any of the image packets retransmitted in response to the Nack packet cannot be correctly received, the Nack packet including the sequence number is re-replyed.
[0157]
The error control scheme 2 processing unit 119 and the error control scheme 3 processing unit 120 return the Ack packet and the Nack packet m times as default, thereby improving the packet collision with the Ack packet and the Nack packet.
[0158]
In addition, the error control scheme selection unit 117 on the transmission side performs the (maximum) number of transmissions l (L) of the same packet according to the communication channel status (reception power information, error detection information, reception status of the Ack packet, and the like). In addition, the maximum number of transmissions n for image data is adjusted to achieve optimization.
[0159]
FIG. 5 is a flowchart illustrating an image transmission procedure in the image communication device according to the first embodiment of the present invention.
[0160]
In FIG. 5, when the user requests image transmission, in step (1), the user inquires whether the image to be transmitted is an image file in the image storage disk 6.
[0161]
If "Yes" is selected in the above step (1), in step (2), the user specifies an image file to be transmitted, and the process proceeds to step (7).
[0162]
If “No” is selected in step (1), a still image is taken by the camera 1 in step (3), and the still image is converted into an image file by the file conversion unit 5, and step (4) Inquires the user as to whether or not to save the captured image file.
[0163]
If "Yes" is selected in step (4), the photographed image file is stored in the image storage disk 6 in step (5), and the process proceeds to step (6). If "No" is selected in step (4), the process proceeds to step (6).
[0164]
Next, in step (6), the user is asked whether to immediately transmit the image file. If "No" is selected, the process ends without transmitting the image file.
[0165]
If "Yes" is selected in step (6), in step (7), the image file is divided by the image dividing unit 8 into K (K is an integer of 2 or more) transmission packet size. ), The image data information of the sequence number 1 and the divided image data from the sequence number 2 to the sequence number (K + 1) are temporarily stored in the transmission buffer unit 9.
[0166]
Next, in step (9), the user is inquired whether to transmit by one-to-many communication (error control method 1) or one-to-one communication (error control method 2 or error control method 3).
[0167]
If one-to-many communication (error control method 1 (a method of transmitting each image packet a plurality of times and not returning an Ack packet)) is selected in the above step (9), the communication processing unit in step (10) At 10, image data information on the image file and a plurality of image packets of each of the plurality of divided image data are generated, and each of these image packets is transmitted l (E) times.
[0168]
Then, in step (11), the transmission of the plurality of image packets is completed 1 (l) times at a time, and in step (12), if the predetermined time has elapsed and a timeout has occurred, the transmission is performed in step (13). The data for the image file in the buffer unit 9 is deleted, and the image transmission procedure ends.
[0169]
If the point-to-point communication is selected in step (9), in step (14), error control method 2 (a method of returning an Ack packet for each image packet) or error control method 3 (all image packets The communication processing unit 10 selects any one of the sequence numbers that could not be received after returning each time as a Nack packet.
[0170]
If the error control method 2 is selected in the above step (14), the image packets of the sequence number k (k is an integer having an initial value of 1 and a maximum value of K + 1) are transferred to a maximum of 1 (L) in steps (15) to (19). ) Times to send.
[0171]
First, the image packet with the sequence number k = 1 is transmitted in the above step (15), and if the Ack packet cannot be received from the destination ID (transmission destination vehicle) in the above step (16), the sequence number is transmitted in the above step (15). Retransmit the image packet with k = 1.
[0172]
If the Ack packet has been received in step (16) or if the number of transmissions in step (15) has reached 1 (ell), all image packets have been transmitted in step (18). Is determined (whether or not k = K + 1) (k = 1 and thus “No”), and in step (19), k is incremented by k = k + 1 (k = 2), In the step (15), the image packet with the sequence number k = 2 is transmitted.
[0173]
In this way, for each image packet, the procedure of steps (15) to (17) is repeated until the Ack packet is received or the number of transmissions of the same packet becomes l, and the sequence number 1 to The image packets up to the sequence number K + 1 are sequentially transmitted.
[0174]
When the transmission of all the image packets is completed in step (18) (if k = K + 1), the data of the image file in the transmission buffer unit 9 is deleted in step (13), and the image transmission procedure is performed. To end.
[0175]
When the error control method 3 is selected in step (14), in step (20), each of the image packets from sequence number 1 to sequence number K + 1 is transmitted l times.
[0176]
When all the image packets are transmitted l (ell) times, in step (21), a Nack packet (retransmission of an image packet having a sequence number that could not be received even by the l (ell) transmissions) is performed. Request packet) or an Ack packet (reception completion packet for all image packets).
[0177]
When the Nack packet is received in step (21), the image packet of the sequence number returned in the Nack packet is retransmitted l (L) times again in step (22).
[0178]
In this way, the steps (21) and (22) are repeated until all the image packets are received at the destination ID (transmission destination vehicle) and the returned Ack packet can be received.
[0179]
When the Ack packet is received in the step (21), the data of the image file in the transmission buffer unit 9 is deleted in the step (13), and the image transmission procedure is ended.
[0180]
If the Ack packet can be received or the total of the number of times (1 time) in which the procedure of step (20) is performed and the number of times in which the procedure of step (22) is performed becomes n times, the image transmission procedure is started. It is also possible to end.
[0181]
As described above, according to the first embodiment, an image file is divided into a plurality of image packets, these image packets are transmitted in bursts, and the ID and GPS information of the own vehicle are periodically transmitted in GPS packets. Accordingly, each vehicle can recognize the surrounding vehicles, and image files can be transmitted between arbitrary vehicles by one-to-one communication or one-to-many communication without depending on infrastructure.
[0182]
In addition, by selecting an optimal error control method according to the communication type and the state of the communication channel and transmitting the image, the number of (maximum) repeated transmissions of the same packet is optimally adjusted according to the state of the communication channel and the like. Thus, the image transmission efficiency can be improved.
[0183]
Further, in the one-to-one communication, the communication quality can be improved by optimally adjusting the transmission priority and the (maximum) number of repeated transmissions of the same packet according to the relative speed between the vehicles.
[0184]
Also, by returning the Ack packet and the Nack packet a plurality of times in one-to-one communication, it is possible to improve packet collision with the Ack packet and the Nack packet.
[0185]
Embodiment 2
FIG. 6 is a configuration diagram of an image communication apparatus according to Embodiment 2 of the present invention, and the same components as those in FIG. 1 are denoted by the same reference numerals. The image communication device according to the second embodiment includes a camera 1, a voice microphone 2, an inter-vehicle communication device 27, a transmission / reception antenna 4, a remote controller 23, and a car navigation system 24, and is installed in a vehicle. The car navigation system 24 includes a memory card 25 and a monitor 26, and is installed in the vehicle.
[0186]
The camera 1, the voice microphone 2, the transmission / reception antenna 4, and the car navigation system 24 are connected to the inter-vehicle communication device 27 by wire or wirelessly. Further, the user can remotely control the inter-vehicle communication device 27 by using the remote controller 23.
[0187]
FIG. 7 is a block diagram of the inter-vehicle communication device 27, and the same components as those in FIG. 2 are denoted by the same reference numerals. 7, the inter-vehicle communication device 27 includes an image storage disk 6, a main control processing unit 28, an image division unit 8, a transmission buffer unit 9, a communication processing unit 10, a peripheral vehicle management unit 11, a reception buffer A section 12 and an image assembling section 13 are provided.
[0188]
The image communication apparatus according to the second embodiment functions as a monitor 14, a memory card 17, and a GPS device 18 (see FIG. 2) of the image communication apparatus according to the first embodiment (see FIG. 2). Image display function), a function of recording image data on a portable and movable recording medium by itself (image data recording function of the memory card 25), a GPS information receiving function (receiving GPS information by a GPS device in a car navigation system) ), The size and cost of the vehicle-to-vehicle communication device are reduced.
[0189]
However, in order to realize the image communication device according to the second embodiment, the car navigation system 24 needs a function of outputting GPS information and a function of displaying input image data from the inter-vehicle communication device 27.
[0190]
The main control processing unit 28 of the inter-vehicle communication device 27 provides the functions of the main control processing unit 7 of the first embodiment with the functions of the file conversion unit 5, the message input unit 15, and the peripheral vehicle management unit 11, An interface function with the car navigation system 24 is provided.
[0191]
In consideration of the operability of the image communication device and the necessity of the control function from the inter-vehicle communication device 27, it is desirable to provide the inter-vehicle communication device 27 with a touch panel and operation keys.
[0192]
As described above, according to the second embodiment, by using the function of the car navigation system as the function of the inter-vehicle communication device, it is possible to reduce the size and cost of the inter-vehicle communication device.
[0193]
It should be noted that the present invention is not limited to the first and second embodiments, and various modifications are possible according to the gist of the present invention, and these are not excluded from the present invention.
[0194]
【The invention's effect】
As described above, according to the present invention, there is an effect that image information can be transmitted between arbitrary image communication apparatuses without depending on infrastructure.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of an image communication device according to a first embodiment of the present invention.
FIG. 2 is a block diagram of an inter-vehicle communication device in the image communication device of FIG. 1;
FIG. 3 is a diagram illustrating operations of an image dividing unit and a transmission buffer unit in the inter-vehicle communication device of FIG. 2;
FIG. 4 is a functional block diagram of a communication processing unit in the inter-vehicle communication device of FIG. 2;
FIG. 5 is a flowchart illustrating an image transmission procedure in the image communication device of FIG. 1;
FIG. 6 is a configuration diagram of an image communication device according to a second embodiment of the present invention.
FIG. 7 is a block diagram of an inter-vehicle communication device in the image communication device of FIG. 6;
[Explanation of symbols]
Reference Signs List 1 camera, 2 voice microphone, 3 inter-vehicle communication device (inter-vehicle communication terminal), 4 transmission / reception antenna, 5 file conversion unit, 8 image division unit, 9 transmission buffer unit, 10 communication processing unit, 11 peripheral vehicle management unit, 12 reception buffer Unit, 13 image assembly unit, 14 monitor, 15 message input unit, 16 personal computer connection interface, 17 memory card, 18 GPS device, 19 operation keys, 23 remote control, 24 car navigation system, 25 memory card, 26 monitor, 27 inter-vehicle communication Device (inter-vehicle communication terminal), 28 main control processing unit, 101 wireless transmission unit, 102 wireless reception unit, 106 transmission packet data generation unit, 107 packet assembler unit, 108 transmission control unit, 109 D / A conversion unit, 110 carrier sense Department, 111 Idol / Visit Judgment unit, 112 random time setting unit, 113 received power measurement unit, 114 A / D conversion unit, 115 packet deassembler unit, 116 error detection unit, 117 error control system selection unit, 118 error control system 1 processing unit, 119 errors Control system 2 processing unit, 120 error control system 3 processing unit, 121 error packet recording unit, 122 retransmission request unit.

Claims (35)

An image communication system configured by a plurality of image communication devices each installed in a mobile body and transmitting image information directly between arbitrary image communication devices,
The image information is divided into a plurality of image packets by a first image communication device, and these image packets are burst-transmitted from the first image communication device to a second image communication device located around the first image communication device. Image communication system. The image communication system according to claim 1,
An image communication system, wherein the first image communication device transmits the image packet to an unspecified number of image communication devices located around the first image communication device. The image communication system according to claim 1,
The first image communication device transmits its own position information packet to an unspecified number of image communication devices located in the vicinity thereof, and transmits the position information packet based on the position information packet transmitted from the image communication device located in the vicinity thereof. An image communication system recognizing a peripheral image communication device and transmitting the image packet to an image communication device specified from the peripheral image communication devices. The image communication system according to claim 3,
The second image communication device transmits its own position information packet to an unspecified number of image communication devices located in the vicinity thereof, and transmits the position information packet based on the position information packet transmitted from the image communication device located in the vicinity thereof. An image communication system recognizing peripheral image communication devices and transmitting a packet requesting image transmission to the first image communication device specified from the peripheral image communication devices. The image communication system according to claim 4,
The image communication system according to claim 1, wherein the first image communication device transmits the image packet to the second image communication device according to the packet requesting image transmission. The image communication system according to claim 1,
Furthermore, the second image communication device transmits the image packet received from the first image communication device to a third image communication device located around the second image communication device. Image communication system. The image communication system according to claim 1,
The first image communication device divides the image information into k (k is an integer of 2 or more), a first image packet formed by image division processing information including the division number k, and each divided image. Generating second to (k + 1) -th image packets composed of information, and transmitting the first image packet first among the first to (k + 1) -th image packets. Image communication system. The image communication system according to claim 1,
The image communication system according to claim 1, wherein the first image communication device transmits each of the image packets a plurality of times. The image communication system according to claim 1,
The second image communication device returns a reception completion packet every time each of the image packets is received,
The image communication system according to claim 1, wherein the first image communication device repeatedly transmits each of the image packets until the reception completion packet is received within a predetermined maximum number of repeated transmissions. The image communication system according to claim 1,
The second image communication device returns a retransmission request packet for the image packet when there is an image packet that could not be received among the image packets, and when all of the image packets have been received, Returns the reception completion packet,
The image communication system according to claim 1, wherein the first image communication device retransmits the image packet requested to be retransmitted upon receiving the retransmission request packet after transmitting each of the image packets a plurality of times. An image communication device for transmitting image information directly to another image communication device located in the vicinity,
The image information is divided by k (k is an integer of 2 or more) into a size that allows packet transmission, image division processing information including the number of divisions k is generated, and a sequence number 1 is added to the image division processing information. Image dividing means for assigning sequence numbers 2 to (k + 1) to each of the obtained image information,
Transmission buffer means for temporarily storing the image division processing information and the divided image information,
An image packet with a sequence number of 1 to (k + 1) is generated from each of the image division processing information and the divided image information, and an image packet to be transmitted first is set as an image packet of sequence number 1, and each of the image packets is generated. Transmitting means for performing burst transmission using the CSMA (Carrier Sense Multiple Access) method. The image communication device according to claim 11,
The image communication device, wherein the transmitting means transmits the image information to an unspecified number of other image communication devices located around the image communication device. The image communication device according to claim 11,
Receiving means for receiving a position information packet transmitted from another image communication device located in the vicinity thereof;
Peripheral vehicle management means for recognizing these peripheral image communication devices by the position information packet and identifying a destination image communication device from these image communication devices,
The transmitting means transmits the position information packet of the own device to an unspecified number of other image communication devices located in the vicinity thereof, and transmits the image packet to the image communication device of the transmission destination. Image communication device. The image communication device according to claim 13,
Further comprising a receiving means for receiving a packet requesting image transmission,
The image communication device, wherein the transmission unit transmits the image packet to another image communication device that has transmitted the packet requesting the image transmission. The image communication device according to claim 13, wherein
The peripheral vehicle management means obtains a relative speed with the specified destination,
The image communication apparatus according to claim 1, wherein the transmission unit sets a priority of communication with the specified destination according to the relative speed. The image communication device according to claim 13,
The image communication apparatus according to claim 1, wherein the transmitting unit generates a position information packet of the own device based on the position information of the own device acquired from a navigation system. The image communication device according to claim 11,
An image communication apparatus, wherein the transmitting means transmits the image packet with information for requesting relay transmission. The image communication device according to claim 11,
The image communication device, wherein the transmitting means transmits each of the image packets a plurality of times. The image communication device according to claim 11,
The image communication apparatus, wherein the transmitting means repeatedly transmits each of the image packets within a range of a predetermined maximum number of repeated transmissions until a reception completion packet for the image packet is received. The image communication device according to claim 11,
The transmitting means, after transmitting each of the image packets a plurality of times, upon receiving a retransmission request packet for any of the image packets, retransmits the retransmitted image packet, and receives the image packet. An image communication device, which ends a transmission process when a completion packet is received. The image communication device according to claim 11,
The transmitting means,
From the first error control method, depending on the communication type of transmitting the image packet to an unspecified number of destinations in the vicinity or transmitting the image packet to a specific destination, and the state of the communication channel Selecting any optimal error control scheme up to the third error control scheme;
When the first error control method is selected, each of the image packets is transmitted a plurality of times,
When the second error control method is selected, each of the image packets is repeatedly transmitted within a predetermined maximum number of repeated transmissions until a reception completion packet for the image packet is received,
If the third error control method is selected, after transmitting each of the image packets a plurality of times, if a retransmission request packet for any of the image packets is received, the image packet requested to be retransmitted is transmitted. An image communication apparatus retransmitting, and upon receiving a reception completion packet for the image packet, ending the transmission processing. The image communication device according to any one of claims 19 to 21,
The image communication device, wherein the transmitting means adjusts the number of repetitive transmissions or the maximum number of repetitive transmissions for the same image packet according to a condition of a communication channel. The image communication device according to any one of claims 19 to 21,
Receiving means for receiving a position information packet transmitted from another image communication device located in the vicinity thereof;
The position information packet recognizes these peripheral image communication devices, identifies a destination image communication device from these image communication devices, and a peripheral vehicle management unit that determines a relative speed with respect to the specified destination. In addition,
The image communication device, wherein the transmitting means adjusts the number of repeated transmissions or the maximum number of repeated transmissions for the same image packet according to the relative speed. The image communication device according to any one of claims 18 to 21,
The image communication device, wherein the transmission buffer means deletes all data on the image information when transmission of all image packets on the image information is completed. The image communication device according to any one of claims 19 to 21,
An image communication apparatus, wherein the transmission buffer means deletes data corresponding to the reception completion packet when the reception completion packet is received. The image communication device according to claim 11,
Image information obtaining means for obtaining an image information by capturing an image;
An image communication device, further comprising a storage unit for recording the image information. An image communication device for receiving image information transmitted from the image communication device according to claim 11,
Receiving means for receiving the transmitted image packet and separating the image division processing information and the divided image information,
A reception buffer means for temporarily storing the image division processing information and the divided image information,
An image communication apparatus, comprising: image assembling means for assembling the divided image information and reproducing the original image information. The image communication device according to claim 27,
Peripheral vehicle management that recognizes these peripheral image communication devices by a position information packet transmitted from another image communication device located in the vicinity thereof, and specifies an image communication device to which an image transmission request is issued from these image communication devices. Means,
Transmitting means for transmitting a packet requesting image transmission to the image communication device of the image transmission request destination,
The image communication device, wherein the receiving means receives the position information packet and receives the image packet transmitted in response to the image transmission request from the image communication device of the image transmission request destination. The image communication device according to claim 27,
An image communication device, further comprising a transmission unit for transmitting an image packet when information for requesting relay transmission is added to the received image packet. The image communication device according to claim 27,
An image communication apparatus, further comprising a transmission unit that returns a reception completion packet a plurality of times each time each of the image packets is received. The image communication device according to claim 27,
If there is an image packet that could not be received among the above image packets, a retransmission request packet for that image packet is returned multiple times, and if all of the above image packets have been received, a reception completion packet is returned multiple times. An image communication apparatus, further comprising a transmission unit that performs the transmission. The image communication device according to claim 30, wherein:
The image communication apparatus, wherein the transmission means adjusts the number of repetitive transmissions for the same reception completion packet or the same retransmission request packet according to the status of a communication channel. The image communication device according to claim 27,
Image display means for displaying the reproduced image information;
An image communication device, further comprising: a storage unit for recording the reproduced image information. The image communication device according to claim 33,
The image communication device, wherein the reception buffer means deletes all data on the image information when the reproduced image information is displayed or recorded. The image communication device according to claim 33,
The image communication device, wherein the image display means displays the reproduced image information on a display device of a navigation system.

Images