JP2011029731A - Video call system, master-side terminal, slave-side terminal, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve higher grade of video to be exchanged with a relatively low cost investment, in a video lecture, video conference, etc., in which three participants or more exist. <P>SOLUTION: Disclosed is a system, wherein video of a master-side terminal 11 that takes over hegemony is distributed constantly to all the slave-side terminals 12, and video of the slave-side terminals 12 are transmitted to only the master-side terminal 11, and wherein, only the slave-side terminals 12 that were given mutual-communication rights by the master-side terminal 11 are able to transmit video to the master-side terminal 11. With such a system, parties that can transmit and receive video with each other are limited to a portion thereof, even though three parties or more can participate simultaneously, and fear of the communication band becoming insufficient is reduced, even when the video to be exchanged is made to be more high-grade. The system does not require the use of a dedicated line, MCU, or IP multicasting, and can be implemented with a relatively low cost investment. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a system for realizing a video call function in which three or more parties can participate.

  Video call systems that realize video lectures or video conferences between multiple points via the Internet or other communication lines are well known (see, for example, the following non-patent documents).

  In existing systems, the compression rate of video data is increased and / or the size or resolution of the video frame is reduced to prevent compression of the bandwidth of the communication line. However, the meaning of video lectures or video conferences could be impaired by the inability to read the letters on whiteboard boards and documents, or the inability to understand the details of models and objects.

  Everyone wants to improve the quality of exchanged video, but if more than three people try to send high-quality video to each of them, the communication bandwidth will be insufficient immediately. If the communication bandwidth is insufficient, video frames are dropped and audio is interrupted, making it no longer suitable for lectures and meetings on important topics. In order to avoid this, it is necessary to use a non-best-effort leased line that guarantees a sufficiently small minimum communication speed, or installs a multi-point control unit (MCU) between each participant (point). It is effective. However, it is undeniable that both require huge investments.

  Although the use of IP (Internet Protocol) multicast technology is also conceivable, at present, it is generally not permitted to perform multicast communication on a public line such as the Internet.

“XVD CamCast (R) CX”, [online], [searched on July 14, 2009], Internet <URL http://www.marubeni-sys.com/bs/xvd/cx.html>

  The present invention made in view of the above is intended to realize high-quality video exchanged with a relatively inexpensive investment in a video lecture or video conference in which three or more participants exist. To do.

  The present invention is a system for realizing a video call function involving transmission / reception of video between a master terminal and a plurality of slave terminals via a telecommunication line, wherein the master terminal includes a plurality of slave terminals. Information indicating that a communication right designation receiving unit that accepts an operation input that designates a slave terminal to which a mutual communication right is to be given and a mutual communication right that is given to a slave terminal that is designated to be given the mutual communication right A communication right granting information transmitting unit for transmitting the communication right granting information, a call receiving unit for receiving an image from a slave terminal currently giving the mutual communication right, and a slave granting the current mutual communication right. A call output control unit that displays the video received from the side terminal on the display screen, and a call transmission unit that transmits the video captured by the camera at the installation location of the main side terminal to each of the plurality of slave terminals. Equipped A call receiving unit that receives images from the master terminal, a call output control unit that displays the video received from the master terminal on the display screen, and a communication right grant from the master terminal A communication right grant information receiving unit that receives information, and a video captured by a camera at the location where the slave terminal is installed on the master terminal only when the communication right grant information is received and the mutual communication right is currently given. A video call system characterized in that a video call system is provided.

  In video lectures and video conferences, in reality, not all participants need images of all other participants. It is usually unthinkable that all participants are equal in lectures and meetings. It is normal for lecturers or lecturers to hold the hegemony at lectures, and chairpersons or moderators at meetings. Also, in many cases, many people speak at the same time. The present invention pays attention to such circumstances, and the video of the master terminal that holds the hegemony is constantly distributed to all slave terminals, while the video of the slave terminal is transmitted only to the master terminal. Furthermore, only the slave side terminal that currently has the mutual communication right transmits the video to the master side terminal.

  According to the present invention, although a system in which three or more parties can participate at the same time, the number of persons who exchange video with each other is limited, so even if the quality of the exchanged video is improved, the communication band is punctured. It reduces. In addition, the system can be operated with a relatively inexpensive investment without using a dedicated line, MCU, or IP multicast.

  The call transmission unit of the slave terminal collects the sound (collects the sound of the site) with the microphone at the location where the slave terminal is installed only when the right of mutual communication is received and the mutual communication right is currently given. The voice receiving unit of the master side terminal receives the voice that comes from the slave terminal that currently gives the mutual communication right, and sends the voice to the master terminal. The call output control unit of the side terminal outputs the sound received from the slave side terminal that currently gives the mutual communication right from the speaker, and the call transmission unit of the main side terminal is a microphone at the installation location of the main side terminal. The voice collected in step 1 is transmitted to each of the plurality of slave terminals, and the voice received from the slave terminal that is currently given mutual communication rights is sent to the slave terminal that is not currently given mutual communication rights. Make a call and receive a call from the slave terminal If the system receives voice from the main terminal, and the call output control unit of the slave terminal outputs the sound received from the main terminal from the speaker, the voice of the main terminal and Only the voice of the slave terminal having the mutual communication right is distributed to each participant. As a result, the communication bandwidth consumption can be further saved. In addition, each person's right to speak can be controlled as appropriate, and orderly lecture management and conference management become possible. In a simple way, you can block your private language and field.

  The communication right designation receiving unit of the master side terminal can receive a designation that the slave terminals that give mutual communication rights should be sequentially switched every predetermined time, and the communication right granting information transmitting unit of the master terminal is If it is a system that sequentially switches the slave terminal of the other party that sends the communication right granting information when the designation that the slave terminal that grants the mutual communication right should be switched sequentially every predetermined time is received, When viewed from the user, for example, the video (and audio) of the user of the slave terminal is automatically switched every tens of seconds to several minutes. As a result, it becomes easy to grasp the movement of the users of all the slave terminals.

  When the slave terminal receives an operation input indicating that a mutual communication right should be requested and an operation input indicating that the mutual communication right should be requested, the slave terminal mutually communicates with the master terminal. A communication right request information transmitting unit for transmitting communication right request information, which is information indicating that a communication right is requested, wherein the master terminal is a communication brought from a slave terminal that is not currently granted a mutual communication right. A communication right request information receiving unit for receiving right request information, and a communication right request output control unit for displaying on the display screen which communication terminal request information is received from which slave terminal; Then, the user of the slave terminal can request the mutual communication right from the user of the master terminal as required. In addition, it becomes possible for the user of the main terminal to select a partner to which the mutual communication right is given in consideration of the request of the user of the slave terminal.

  If the main terminal also has the function as the slave terminal, the master terminal and the slave terminal can be shared, which contributes to a reduction in the manufacturing cost of the terminal.

  According to the present invention, it is possible to realize high-quality video exchanged with a relatively inexpensive investment in a video lecture or video conference where there are three or more participants.

The figure which shows the outline | summary of the video call system of one Embodiment of this invention. The figure which shows the hardware resource which the terminal in the embodiment comprises. Functional block diagram of the terminal. Functional block diagram of the terminal. The figure which illustrates the information memorize | stored and accumulated in the telephone directory memory | storage part. The figure which shows the example of a screen display on a terminal. The figure which shows the example of a screen display on a terminal. The figure which shows the example of a screen display on a terminal. The figure which shows the example of a screen display on a terminal. The figure which shows the example of a screen display on a terminal. The flowchart which shows the procedure of the process which a terminal performs according to a program. The flowchart which shows the procedure of the process which a terminal performs according to a program.

  An embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the video call system according to the present embodiment has terminals 1 distributed in various places connected to an electric communication line 2 such as the Internet, a WAN (Wide Area Network), a LAN (Local Area Network) and the like. It is constructed to connect to each other via the communication. At least one of the terminals 1 is the master terminal 11, and the remaining plurality are slave terminals 12.

  As shown in FIG. 2, the terminal 1 includes a processor 1a, a main memory 1b, an auxiliary storage device 1c, an operation input device 1d, a microphone 1e, a speaker 1f, an audio codec 1g, a camera 1h, a display 1i, a video codec 1j, and a communication interface. Hardware resources such as 1k are provided, and these are controlled by a controller (system controller, I / O controller, etc.) 11 to perform a cooperative operation.

  The auxiliary storage device 1c is a hard disk drive, a flash memory, an optical disk drive, or the like.

  The operation input device 1d is a pointing device such as a push button that can be operated with a finger, a touch panel, or a track pad. In this embodiment, a remote controller that can wirelessly communicate with the terminal 1 is assumed.

  The audio codec 1g encodes the sound collected via the microphone 1e, or decodes the encoded sound information and outputs the sound from the speaker 1f. The video codec 1j encodes video captured through the camera 1h, decodes encoded video information, and displays and outputs it on the screen of the display 1i. Each of the audio codec 1g and the video codec 1j can be implemented as software instead of hardware.

  The communication interface 1g is a device for performing information communication via the telecommunication line 2 and is typified by NIC (Network Interface Card) or wireless LAN transceiver, but besides these, USB (Universal Serial Bus), IEEE 1394, etc. The interface can also be adopted.

  The terminal 1 is basically a dedicated device manufactured for the purpose of constructing this system. However, it does not prevent the terminal 1 according to the present invention from being configured by installing a program necessary for a general-purpose personal computer, workstation, video game machine or the like.

  A program to be executed by the processor 1a is stored in the auxiliary storage device 1c. When the program is executed, the program is read from the auxiliary storage device 1c into the main memory 1b and decoded by the processor 1a. The terminal 1 operates the hardware resource according to the program, and exhibits the function of the master terminal 11 shown in FIG. 3 and the function of the slave terminal 12 shown in FIG.

  The main terminal 11 includes a telephone directory storage unit 111, a call request transmission unit 112, a call reception unit 113, a call output control unit 114, a call transmission unit 115, a communication right request information reception unit 116, and a communication right request output control unit 117. A communication right designation receiving unit 118 and a communication right giving information transmitting unit 119.

  The telephone directory storage unit 111 stores identification information of one or more (for example, a maximum of 100) terminal 1 and attribute information related to the terminal 1 using a storage area of the main memory 1b or the auxiliary storage device 1c. . The identification information is information for identifying a communication destination represented by, for example, an IP address, a SIP (Session Initiation Protocol) address, and other URIs. The attribute information is information related to the other party's name or name, affiliation, location, and other destinations, and is character string information in this embodiment. FIG. 5 illustrates information stored in the telephone directory storage unit 111. The telephone directory storage unit 111 stores identification information and attribute information in association with an ID number or the like for each terminal 1 for other terminals 1 that can be candidates for a video call partner.

  The identification information and attribute information of the other terminal 1 may be manually input directly, or may be transmitted from another terminal 1 or a computer connected via the telecommunication line 2. The terminal 1 accepts input of identification information and attribute information of the other terminal 1 via the operation input device 1d or receives it using the function of the communication interface 1k and registers it in the telephone book (or address book). That is, it is stored in the telephone directory storage unit 111.

  It is also possible to store identification information and attribute information related to another terminal 1 that has made a video call in the past as a past call history in the telephone directory. In this case, as attribute information, information indicating whether the call was made (calling) from us or received (received) from the other party, and the date and time when the video call was made with the terminal 1 are shown. The time stamp and the like are also stored. In particular, as shown in FIG. 5, for a plurality of terminals 1 that have participated in a video lecture or video conference held in the past, information to that effect and a time stamp indicating the date and time of the lecture or conference are stored. I can leave.

  When holding a video lecture or video conference, the call request transmission unit 112 uses a function of the communication interface 1k to make a call request for making a video call with the terminal 1 participating in the lecture or conference. send. In order to start a video lecture or video conference, it is necessary to establish a session between the master terminal 11 and each slave terminal 12. In principle, the call request is transmitted from the master terminal 11 to the slave terminal 12. However, the mode in which the call request is transmitted from the slave terminal 12 to the master terminal 11 is not disturbed.

  The main terminal 11 displays on the screen of the display 1i a list of other terminals 1 that can be candidates for video call destinations, that is, candidates for participation in lectures or conferences. FIG. 6 shows a candidate list display example. The terminal 1 that is first displayed as a candidate is the terminal 1 that has participated in a lecture or a meeting in the past (the history information is left in the telephone directory storage unit 111). The main terminal 11 reads identification information from the telephone directory storage unit 111 for each of the plurality of candidate terminals 1. Then, based on the identification information, a live icon request that is information requesting the terminal 1 to transmit a live icon (symbol B in the figure) is transmitted. The live icon is a real-time video or still image taken at the place where the terminal 1 is installed. The size of the live icon (for example, 192 × 108 pixels) is smaller than the size of the image exchanged during the video lecture or video conference (for example, 1920 × 1080 pixels). The frame rate of the live icon is affected by the bandwidth of the telecommunication line 2 to which each terminal 1 is connected, but is about 5 fps or more.

  In the system of the present embodiment, in principle, the terminals 1 are interconnected in a peer-to-peer manner via the telecommunication line 2. That is, when conducting a video lecture or video conference, it is not necessary to use another relay server or a relay machine such as an MCU. When the identification information does not require address resolution such as an IP address, a live icon request can be immediately transmitted to the terminal 1 using the identification information. When the identification information requires address resolution, such as a SIP address, the invitee terminal 12 and the callee terminal 12 can be contacted by transmitting an invitation message to another computer (for example, a SIP proxy server) using the identification information. Establish a session between them, and then send a live icon request. Alternatively, the identification information is transmitted to another computer (for example, a DNS (Domain Name System) server) having an address resolution capability, and an IP address corresponding to the identification information is received from the computer, and the IP address, etc. A live icon request is transmitted to the terminal 1 using.

  The terminal 1 that has received the live icon request normally transmits the live icon captured by the camera 1h to the terminal 1 that has caused the live icon request. The main terminal 11 receives the live icon returned from each terminal 1, and displays it on the screen of the display 1i together with the attribute information (reference symbol A in the figure) of the terminal. Since the live icon cannot be displayed for the terminal 1 that has not received the live icon, an image or a character string indicating that fact is displayed. In the example shown in FIG. 6, the display of “Connecting ...” (reference symbol C in the figure) indicates that a live icon request is transmitted to the terminal 1 and a response is awaited. The display of “communication impossible” (symbol D in the figure) indicates that a response has not been returned until a certain time has elapsed after transmitting a live icon request to the terminal 1, that is, for some reason (the power supply of the terminal 1 is The communication line to which the terminal 1 is connected is interrupted, etc., indicating that it is impossible to establish a session with the terminal 1. A display of “not displayable” (symbol E in the figure) indicates that a live icon request is transmitted to the terminal 1, but the live icon request is rejected, in other words, a response that the live icon is not transmitted is live. Indicates that it was sent instead of an icon. In the display of “busy” (symbol F in the figure), a live icon request is transmitted to the terminal 1, but a response indicating that a video call is already being made with another terminal 1 is sent instead of the live icon. It shows that it has come.

  Thus, the master terminal 1 sends operation inputs for designating a plurality of slave terminals 12 to be participants in the video lecture or video conference from the candidates displayed on the screen via the operation input device 1d. Accept. The user of the master terminal 1 operates the operation input device 1d to move the cursor (symbol G in the figure), and clicks the information display column (symbols A and B in the figure) of the desired slave terminal 12. The main terminal 1 that has received this operation knows the terminal 1 corresponding to the clicked display field as a participant, and starts the video call to the terminal 1 based on the identification information related to the terminal 1. Send the requested call request. Even if the identification information related to the slave terminal 12 requires address resolution, if the session has already been established or address resolution has already been completed at the live icon request transmission stage, a call request is made directly to the slave terminal 12. Can be sent. Otherwise, session establishment or address resolution is performed in the same manner as when the live icon request is transmitted, and a call request is transmitted to the slave terminal 12. Incidentally, the terminal 1 that displays “communication impossible” or “busy” instead of the live icon cannot be designated as a participant (the cursor cannot be moved to the information display field related to the terminal 1). I am doing so.

  The call receiving unit 113 receives video and audio transmitted from the slave terminal 12 due to the transmission of the call request using the function of the communication interface 1k. However, transmission of video and audio to the master terminal 11 is limited to the slave terminal 12 that currently has a mutual communication right, and the call receiver 113 also receives the slave terminal 12. Only the video and audio captured and picked up at

  The call output control unit 114 displays the video during a call received from the slave terminal 12 on the screen of the display 1i, and outputs the voice during the call received from the slave terminal 12 from the speaker 1f. FIG. 7 shows a display output example of the image of the other party during the video call in the main terminal 11. On this call screen, a video (symbol H in the figure) taken by the slave terminal 12 that currently has a mutual communication right is greatly displayed. In addition, the call output control unit 114 displays on the call screen a small self-portrait (symbol I in the figure) captured by the camera 1h at the location where the main terminal 11 is installed.

  The call sending unit 115 sends the video captured by the camera 1h at the installation location of the main terminal 11 and the sound collected by the microphone 1e to all the slave terminals 12 participating in the video lecture or video conference. , Using the function of the communication interface 1k. In the present embodiment, the voice of the slave terminal 12 that currently has the right to communicate is distributed and shared to the terminals 1 of all participants via the master terminal 11. Therefore, the call transmitting unit 115 has the mutual communication right for all the slave terminals 12 that do not have the mutual communication right together with the own voice collected at the installation location of the main terminal 11. The voice received from the slave terminal 12 is also transmitted. At that time, the call transmission unit 115 sends out voice data obtained by superimposing the received voice on the voice collected by the microphone 1e.

  The communication right request information receiving unit 116 receives the communication right request information, which is information from the slave terminal 12 to request the mutual communication right, using the function of the communication interface 1k. The communication right request receiving unit also receives cancellation information, which is information indicating that the request for mutual communication right, which is provided from the slave terminal 12, is cancelled.

  The communication right request output control unit 117 displays on the screen of the display 1i which slave terminal 12 has received the communication right request information. FIG. 8 shows a display example of the communication right request. This control screen displays a list of attribute information (symbol J in the figure) and its current status for all slave terminals 12 participating in the video lecture or video conference. In the example shown in FIG. 8, “in communication” (symbol K in the figure) indicates that a session has been established with the slave terminal 12, and the slave terminal 12 of the other party has sent from the master terminal 11. The video and audio that are being played will be received. The display of “request to speak” (symbol L in the figure) indicates that the communication right request information has been received from the slave terminal 12. When the cancel information is transmitted from the slave terminal 12 that has brought the communication right request information and is received, the display of “request to speak” is returned to the display of “in communication”. Incidentally, the display of “disconnected” (symbol M in the figure) indicates that the session with the slave terminal 12 has been disconnected for some reason.

  The control screen is displayed only when the user of the main terminal 11 performs a predetermined operation via the operation input device 1d during a video lecture or video conference. The purpose of not always displaying the control screen is to prevent the mental concentration of the user of the main terminal 11, particularly a lecturer or a lecturer. If the user of the main terminal 11 has clicked the “return” button (symbol S in the figure), the control screen shown in FIG. 8 is hidden and shown in FIG. Return to the original call screen.

  Note that the above-described live icon may be displayed on the control screen shown in FIG. 8 instead of “in communication”, “disconnect”, or the like. In this case, the master terminal 11 that has received a predetermined operation for displaying the control screen transmits a live icon request to each slave terminal 12, and the slave terminal 12 that has received the live icon request captures a live icon image. And return it to the main terminal 11. Then, the main terminal 11 displays the received live icon in the control screen. Further, when the master terminal 11 receives an operation for concealing the control screen, that is, a click operation of the “return” button, information indicating that the slave terminal 12 requests transmission of the live icon to each slave terminal 12 is displayed. Send. Receiving this, the slave terminal 12 stops capturing and transmitting the live icon image.

  When the communication right request information is received during the period in which the call screen shown in FIG. 7 is displayed, the fact (N in the figure) is displayed small in the corner. The display indicating that the request for communication right has been received is deleted when cancel information is received from the same slave terminal 12.

  The communication right designation accepting unit 118 accepts an operation input for designating the slave terminal 12 to which the mutual communication right is to be given from among the plurality of slave terminals 12 via the operation input device 1d. The user of the master side terminal 1 operates the operation input device 1d on the control screen shown in FIG. 8 to move the cursor (symbol O in the figure) and displays it in the desired slave terminal 12 column. Click the “Select” button (symbol P in the figure). The master side terminal 11 that has received this operation knows the slave side terminal 12 corresponding to the clicked button as the terminal 12 that should be given the mutual communication right. However, for the slave terminal 12 which has already given the mutual communication right, an image or a character string (symbol Q in the figure) indicating that is displayed instead of the “select” button.

  Further, the communication right designation receiving unit 118 can receive a designation that the slave terminals 12 that give mutual communication rights should be sequentially switched every predetermined time. On the screen shown in FIG. 8, a button (symbol R in the figure) for automatically switching the destination to which the mutual communication right is given is displayed. These buttons are used to select the time of the switching cycle. In the illustrated example, one of “10 seconds”, “30 seconds”, “1 minute”, and “3 minutes” is selected. On the control screen shown in FIG. 8, the user of the main terminal 1 operates the operation input device 1d to move the cursor and clicks a button having a desired cycle time. The master side terminal 11 that has received this operation knows that it has been designated that the slave side terminal 12 to which the mutual communication right is to be switched in the time period corresponding to the clicked button.

  The communication right granting information transmitting unit 119 provides the communication right granting information, which is information indicating that the mutual communication right is given to the slave terminal 12 designated to be given the mutual communication right, and the function of the communication interface 1k. Use to send. The communication right granting information transmitting unit transmits the communication right granting information to the slave terminal 12 designated by the user of the master terminal 11, and at the same time, the slave terminal 12 having the mutual communication right until then. The communication right revocation information indicating that the mutual communication right is lost is transmitted to the terminal.

  When the user of the master side terminal 11 specifies that the slave side terminal 12 that grants the mutual communication right at every predetermined time should be sequentially switched, the user has the right of mutual communication at every time period selected by the user. The communication right revocation information is transmitted to the slave terminal 12 that is performing communication, and the communication right grant information is transmitted to the slave terminal 12 that does not have the mutual communication right corresponding to the next order.

  The slave terminal 12 includes a call request receiving unit 121, a call receiving unit 122, a call output control unit 123, a communication right request receiving unit 124, a communication right request information transmitting unit 125, a communication right granting information receiving unit 126, and a call transmitting unit. 127.

  The call request receiving unit 121 receives a call request transmitted from the main terminal 11 that is a partner of a video call by using the function of the communication interface 1k. Upon reception of the call request, it is determined that the slave terminal 12 and the master terminal 11 participate in mutual communication and that the slave terminal 12 participates in a video lecture or video conference hosted by the master terminal 11.

  The call receiver 122 receives video and audio transmitted from the main terminal 11 by using the function of the communication interface 1k. The video received by the call receiving unit 122 is a video shot at the main terminal 11. On the other hand, the voice received by the call receiving unit 122 is only the voice collected by the main terminal 11 when the slave terminal 12 currently has the mutual communication right. Is the voice collected at the master terminal 11 and the voice collected at the slave terminal 12 having the mutual communication right.

  The call output control unit 123 displays a video during a call received from the main terminal 11 on the screen of the display 1i and outputs a voice during a call received from the main terminal 11 from the speaker 1f. FIG. 9 shows a display output example of the image of the other party during the video call in the slave terminal 12. On the call screen, a video image (symbol T in the figure) taken by the main terminal 11 is greatly displayed. In addition, the call output control unit 123 displays a small image of the self (photograph U in the figure) captured by the camera 1h at the place where the slave terminal 12 is installed in the call screen.

  The communication right request accepting unit 124 accepts an operation input for requesting a mutual communication right from the user of the main terminal 11 via the operation input device 1d. On the call screen of the slave terminal 12, a “speak request” button (reference symbol V) is displayed. On the screen shown in FIG. 9, the user of the slave terminal 12 who wishes to grant the mutual communication right operates the operation input device 1d to move the cursor (not shown) and clicks the “Request to speak” button. To do. The slave terminal 12 that has received this operation knows that it has been instructed to request the mutual communication right.

  The communication right request information transmitting unit 125 transmits the communication right request information to the main terminal 11 using the function of the communication interface 1k when receiving an operation input for requesting the mutual communication right. .

  After transmitting the communication right request information, an image or character string (symbol W in the figure) indicating that is displayed on the call screen of the slave terminal 12 as shown in FIG. Instead of this, a “desired stop” button (symbol X in the figure) is displayed. When the user of the slave terminal 12 has performed an operation of clicking the “cancel request” button, the cancel information is transmitted to the master terminal 11 and the “desired to speak” display is erased. Change the "Cancel request" button back to the "Request to speak" button.

  The communication right grant information receiving unit 126 receives the communication right grant information provided from the main terminal 11 by using the function of the communication interface 1k. Further, the communication right grant information receiving unit 126 also receives the communication right revocation information provided from the main terminal 11.

  The call transmission unit 127 receives the video captured by the camera 1h and the sound collected by the microphone 1e only when the communication right granting information is received and the mutual communication right is currently given. The main terminal 11 is transmitted using the function of the communication interface 1k. After receiving the communication right revocation information from the main terminal 11, since the mutual communication right is lost, transmission of its own video and audio toward the main terminal 11 is stopped. Even during the period before the mutual communication right is given, it does not transmit its own video and audio.

  A procedure of processing executed by the terminal 1 constituting the video call system of the present embodiment during the video lecture or video conference will be outlined. As shown in FIG. 11, the master terminal 11 receives the video and audio transmitted from the slave terminal 12 having the mutual communication right (step S1), and receives the received video and audio via the display 1i and the speaker 1f. (Step S2). At the same time, the self-image captured by the camera 1h and the own sound collected by the microphone 1e are transmitted to all the slave terminals 12 participating in the video lecture or video conference (step S3). In step S3, the slave terminal 12 that does not have the mutual communication right superimposes and transmits the voice received from the slave terminal 12 that has the mutual communication right on its own voice.

  When the master terminal 11 receives the communication right request information from any of the slave terminals 12 (step S4), it informs that the user of the slave terminal 12 is requesting the mutual communication right. Information is displayed on the screen of the display 1i (step S5).

  Further, when the master terminal 11 receives an operation input for designating the slave terminal 12 that gives the right of mutual communication by the user of the master terminal 11 (step S6), the master terminal 11 receives the designated slave terminal 12 from the user. Communication right granting information is transmitted toward (step S7). At the same time, the communication right revocation information is transmitted to the slave terminal 12 that has had the mutual communication right so far (step S8).

  The main terminal 11 repeats the above steps S1 to S8 until the end of the video lecture or video conference (step S9).

  As shown in FIG. 12, the slave terminal 12 receives the video and audio transmitted from the master terminal 11 (step S10), and outputs the received video and audio via the display 1i and the speaker 1f (step S10). S11).

  The slave terminal 12 receives the communication right request information for the master terminal 11 when receiving an operation input for requesting the mutual communication right by the user of the master terminal 12 (step S12). Transmit (step S13).

  Then, the slave terminal 12 is given the mutual communication right (step S14), in other words, on the condition that the communication right grant information is received from the master side terminal 11, the own terminal 12 has taken its own image. The video and the voice collected by the microphone 1e are transmitted to the main terminal 11 (step S15). The transmission of its own video and audio continues until the given mutual communication right expires, that is, until communication right revocation information is received from the main terminal 11.

  The slave terminal 12 repeats the above steps S10 to S15 until the end of the video lecture or video conference (step S16).

  The present invention is not limited to the embodiment described in detail above. First, in the above embodiment, among the plurality of slave terminals, only the terminal that is currently given the mutual communication right is supposed to be able to transmit the voice. It is good also as what can transmit / receive arbitrarily. The bit rate of audio data is an order of magnitude smaller than that of video data, and transmission from all terminals participating in a lecture or conference to all other terminals does not necessarily cause a shortage of communication bandwidth. Because it is considered.

  In the above embodiment, the mutual communication right is given to only one slave terminal. However, the mutual communication right may be given to a plurality of slave terminals simultaneously. In this case, a plurality of slave terminals to which mutual communication rights are given are transmitted to the master terminal as their own video (and audio), and the master terminal that receives them transmits video from a plurality of slave terminals. (And voice) are output simultaneously.

  A plurality of main terminals may be provided. In this case, the own video (and audio) is transmitted from the slave terminal having the mutual communication right to each master terminal. It is also allowed for the main terminals to mutually transmit and receive their own video (and audio).

  Further, in the above embodiment, video, audio, communication right granting information and other information are transmitted and received between terminals in a peer-to-peer form. However, these may be transmitted and received via a relay device such as an MCU or a relay server. It does not prevent it.

  In addition, the specific configuration of each unit, the processing procedure, and the like can be variously modified without departing from the spirit of the present invention.

  The present invention can be used, for example, as a system for realizing a video lecture or video conference between multiple points.

DESCRIPTION OF SYMBOLS 1 ... Terminal 11 ... Master side terminal 12 ... Slave side terminal

Claims (9)

A system for realizing a video call function involving transmission / reception of video between a master terminal and a plurality of slave terminals via a telecommunication line,
The master terminal
A communication right designation accepting unit for accepting an operation input for designating a slave terminal to which a mutual communication right should be given from among a plurality of slave terminals;
A communication right granting information sending unit for sending communication right granting information which is information indicating that a mutual communication right is given to a slave terminal designated as being given the mutual communication right;
A call receiver that receives images from a slave terminal that is currently granting mutual communication rights;
A call output control unit that displays on the display screen the video received from the slave terminal that currently gives the mutual communication right;
A call transmission unit configured to transmit video captured by the camera at the installation location of the primary terminal to each of the multiple secondary terminals;
The slave terminal
A call receiving unit for receiving images from the main terminal,
A call output control unit for displaying video received from the main terminal on the display screen;
A communication right grant information receiving unit for receiving the communication right grant information brought from the main terminal;
A call sending unit for sending video taken by the camera to the master side terminal only when receiving the right to grant communication and the mutual right to give is currently given. A video call system characterized by The call transmission unit of the slave terminal receives the voice granted by the microphone at the installation location of the slave terminal only when the right of mutual communication is received and the right of mutual communication is given to the master terminal. Outgoing,
The call receiving unit of the master side terminal receives the voice from the slave terminal currently giving the mutual communication right,
The call output control unit of the master terminal causes the speaker to output the sound received from the slave terminal currently giving the mutual communication right,
The call transmitting unit of the main terminal transmits the sound collected by the microphone at the installation location of the main terminal to each of the plurality of slave terminals, and currently gives the mutual communication right To the slave terminal that is not currently granted the right to interact,
The call receiving unit of the slave terminal receives the voice from the master terminal,
The video call system according to claim 1, wherein the call output control unit of the slave terminal outputs sound received from the master terminal from a speaker. The communication right designation accepting unit of the master side terminal can accept the designation that the slave side terminals that give mutual communication right every predetermined time should be switched sequentially,
The communication right granting information sending part of the master side terminal receives the designation that the slave side terminals that give mutual communication rights should be sequentially switched every predetermined time, and the slave side of the other party that sends the communication right granting information The video call system according to claim 1 or 2, wherein the terminals are sequentially switched. The slave terminal is
A communication right request accepting unit that accepts an operation input indicating that a mutual communication right should be requested;
A communication right request information transmitting unit for transmitting communication right request information, which is information indicating that a mutual communication right is requested to the main terminal when an operation input indicating that the mutual communication right should be requested is received; Equipped,
The main terminal is
A communication right request information receiving unit that receives communication right request information that is provided from a slave terminal that is not currently granted a mutual communication right;
4. The video call system according to claim 1, further comprising a communication right request output control unit for displaying on the display screen which communication terminal request information has been received from which slave terminal. The video call system according to claim 1, 2, 3, or 4, wherein the master terminal also has a function as the slave terminal. It is used for configuring the video call system according to claim 1, 2, 3, 4 or 5,
A communication right designation accepting unit for accepting an operation input for designating a slave terminal to which a mutual communication right should be given from among a plurality of slave terminals;
A communication right granting information sending unit for sending communication right granting information which is information indicating that a mutual communication right is given to a slave terminal designated as being given the mutual communication right;
A call receiver that receives images from a slave terminal that is currently granting mutual communication rights;
A call output control unit that displays on the display screen the video received from the slave terminal that currently gives the mutual communication right;
A main-side terminal comprising: a call transmission unit configured to transmit a video photographed by a camera at a location where the main-side terminal is installed to each of a plurality of slave terminals. It is used for configuring the video call system according to claim 1, 2, 3, 4 or 5, comprising:
A communication right designation accepting unit that accepts an operation input for designating a slave terminal to which a mutual communication right should be given from among a plurality of slave terminals.
A communication right granting information sending unit for sending communication right granting information, which is information indicating that a mutual communication right is given to a slave terminal designated to be given a mutual communication right,
A call receiver that receives images from slave terminals that currently give mutual communication rights,
A call output control unit that displays video received from a slave terminal currently giving mutual communication right on the display screen, and
A program that functions as a call transmission unit that transmits video captured by a camera to each of a plurality of slave terminals at the installation location of the master terminal. It is used for configuring the video call system according to claim 1, 2, 3, 4 or 5,
A call receiving unit for receiving images from the main terminal,
A call output control unit for displaying video received from the main terminal on the display screen;
A communication right grant information receiving unit for receiving the communication right grant information brought from the main terminal;
Only when receiving the communication right granting information and when the mutual communication right is currently given, the slave is provided with a call sending unit that sends the video taken by the camera to the master side terminal at the installation location of the slave side terminal. Side terminal. It is used for configuring the video call system according to claim 1, 2, 3, 4 or 5, comprising:
A call receiver that receives images from the main terminal,
Call output control unit that displays video received from the main terminal on the display screen,
A communication right grant information receiving unit for receiving the communication right grant information brought from the main terminal, and
A program that functions as a call transmission unit that transmits video captured by a camera at a location where a slave terminal is installed to a master terminal only when the communication right grant information is received and the mutual communication right is currently given.

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