JPH10136328A - Communication control system for multi-point communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To display a composited image by using a communication terminal having already been in existence in a field as it is within a framework of a currently available standard communication control system among communication terminals by multi-vendor system with respect to the communication control system for the multi-point communication system. SOLUTION: An image composition means 3a composites images sent from a plurality of communication terminals 1a-1z to send a composited image. A list transmission means 3b generates a list of each identification code corresponding respectively to the communication terminals 1a-1z and the image composition means 3a and transmits the list to a plurality of the communication terminals 1a-1z. A communication terminal references the list to select an identification number and gives it to an image output means 3c. The image output means 3c recognizes the communication terminal corresponding to the identification code or the image composition means 3a and outputs the image received from the communication terminal or the image composition means 3a to a prescribed communication terminal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication control method for a multipoint communication system, and more particularly, to a plurality of communication terminals having different operation specifications and a multipoint communication terminal connected to the plurality of communication terminals via a network. The present invention relates to a communication control method for a multipoint communication system including a communication central control device.

[0002] In recent years, the market for communication terminals for transmitting and receiving images and sounds in real time has been rapidly growing with the spread of digital integrated networks (ISDN).
In particular, with the rapid increase in the number of communication terminals shipped, not only is it used as a video phone for connecting each communication terminal one-to-one, but also as a video conference in which many communication terminals are connected simultaneously.

[0003] In the case of a video conference, a service for mixing sounds at all points and transmitting them to each point, a service for selecting an image of a specific point and transmitting it to each point, and synthesizing images of a plurality of points to make each area There is a demand for a multipoint communication service such as a service for transmitting to a point. A multipoint communication system that provides such a multipoint communication service is realized by interconnecting a large number of communication terminals with a center device via a digital integrated network (ISDN) or the like.

[0004]

2. Description of the Related Art In a video conference, there is a user demand that an operator of a communication terminal on the receiving side freely select a composite image of a plurality of points or an image of a specific point. Conventionally, a multipoint communication system provided by the same manufacturer and configured by devices having uniform specifications has been able to meet such demands.

[0005]

However, with an increase in the scale of the system, an unspecified number of communication terminals are connected via a public network, and a number of different manufacturers are provided in a multipoint communication system. There is a situation where communication terminals provided by (multi-vendor) are mixed. Since multi-vendor communication terminals have different specifications, the functions that multipoint communication systems can currently achieve are:
International Standard ITU-T / H. H.243 is limited to the following standard communication control method. a) The center device compares the level values of all the received voices from the communication terminals currently participating in the video conference,
A communication terminal having the maximum reception audio level is detected, and an image of a conference room or the like sent from the detected communication terminal is automatically displayed on another communication terminal. b) The operator of each communication terminal selects a specific communication terminal from among the communication terminals currently participating in the video conference, and displays an image sent from the specific communication terminal on the own communication terminal. . c) The operator of each communication terminal requests that the image of the own communication terminal be simultaneously broadcast to another communication terminal, and in accordance with this request, the image of that communication terminal is forcibly displayed on the other communication terminals. d) The operator of each communication terminal makes his / her own communication terminal recognized as the chair, and the operator of the communication terminal that has become the chair selects an image of any communication terminal and broadcasts it to other communication terminals simultaneously. In response to the request, the image of the selected communication terminal is forcibly displayed on another communication terminal. e) In addition, although the image of the conference room or the like is not displayed, the name of the conference room or the like of all communication terminals participating in the conference or the name of the conference room or the like of the communication terminal currently displaying an image is displayed in each communication terminal. Display to the operator.

[0006] As described above, in the communication control that can be performed between the communication terminals provided by the multi-vendor, in any case, only a single image sent from a single communication terminal is displayed on the communication terminal. There is no communication control function for displaying an image obtained by combining images sent from a plurality of communication terminals.

That is, in a video conference, a multi-vendor is provided by a multi-vendor in response to a user request that an operator of a receiving communication terminal wants to freely select a composite image of a plurality of points or an image of a specific point. The only function that can be realized by the current standard communication control method that can be performed between the communication terminals is to select an image at a specific point (the above item b).

[0008] Even if a control function related to a composite image is added to a standard communication control method that can be provided between communication terminals provided by a multi-vendor in the future, a huge number of existing functions already exist in the field. It is impossible to add a new function to the communication terminal in terms of the amount of work and cost.

[0009] The present invention has been made in view of the above points, and within the framework of the current standard communication control method that can be performed between communication terminals provided by a multi-vendor,
It is an object of the present invention to provide a communication control method for a multipoint communication system that can display a composite image even when a communication terminal already existing in a field is used as it is.

[0010]

According to the present invention, in order to achieve the above object, as shown in FIG. 1, a plurality of communication terminals 1a to 1z having different operation specifications and a plurality of communication terminals 1a to 1z are connected. In the communication control method of the multipoint communication system constituted by the multipoint communication central control device 3 connected via the network 2, the multipoint communication central control device 3 is transmitted from a plurality of communication terminals 1a to 1z. Image synthesizing means 3a for synthesizing the image and sending out the synthesized image;
A plurality of communication terminals 1a to 1z and image combining means 3
list sending means 3b for sending a list of each identification code respectively corresponding to a to a plurality of communication terminals 1a to 1z.
Receiving the identification code selected from the list sent by the list sending means 3b and sent from the first communication terminal, and sent from the communication terminal or the image synthesizing means 3a corresponding to the identification code. And an image output means 3c for outputting the output image to a predetermined communication terminal.

In the above configuration, a plurality of communication terminals 1a to 1z are provided by a multi-vendor,
Therefore, the communication terminals 1a to 1z have different operation specifications. Therefore, conventionally, the international standard ITU-T / H. Only the function of the H.243 communication control method can be realized.

However, in the present invention, the image synthesizing means 3a is provided to synthesize the images sent from the plurality of communication terminals 1a to 1z and to send out the synthesized image. A plurality of the image synthesizing means 3a may be provided so that different synthetic images are created respectively. here,
Although the description will be made assuming that one is provided, the same applies in principle to a plurality of cases.

The list sending means 3b assigns an identification code corresponding to the image synthesizing means 3a to an identification code corresponding to each of the communication terminals 1a to 1z.
To 1z in the same manner as the corresponding identification codes, and a list is created.
a to 1z.

A first communication terminal, which is one of the plurality of communication terminals 1a to 1z, selects a certain identification number with reference to the list sent by the list sending means 3b. This selection is exactly the same as in the conventional case where the selection is made based on a list consisting only of the identification codes corresponding to the communication terminals 1a to 1z, respectively. Therefore, provided by multi-vendor,
Even the communication terminals 1a to 1z having different operation specifications can be selected without any trouble.

The selected identification number is sent from the first communication terminal to the image output means 3c. Image output means 3
c receives the transmitted identification code, recognizes the communication terminal or the image synthesizing means 3a corresponding to the identification code, and transmits the image transmitted from the communication terminal or the image synthesizing means 3a to a predetermined communication terminal. Output. The predetermined communication terminal may be the first communication terminal or may be all of the communication terminals 1a to 1z. If the selected identification number corresponds to the image combining means 3a, the combined image will be output to a predetermined communication terminal.

In this way, the first communication terminal, which is a certain communication terminal, is exactly the same as the conventional method in which a single image from a single communication terminal is selected and displayed on a predetermined communication terminal. By simply performing the operation, the composite image can be selected and displayed on a predetermined communication terminal.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. First, the principle configuration of the first embodiment will be described with reference to FIG. In the first embodiment,
An image synthesizing unit 3a for synthesizing images sent from the plurality of communication terminals 1a to 1z and sending out a synthesized image, and a list of each identification code corresponding to each of the plurality of communication terminals 1a to 1z and the image synthesizing unit 3a is stored in a plurality of lists. A list sending means 3b for sending to the communication terminals 1a to 1z, and an identification code selected by referring to the list sent by the list sending means 3b and sent from the first communication terminal is received. And an image output means 3c for outputting an image sent from the corresponding communication terminal or image synthesizing means 3a to a predetermined communication terminal.

A specific detailed configuration of the first embodiment will be described with reference to FIGS. FIG.
2 and the configuration described with reference to FIGS. 2 to 4 will be described after the description with reference to FIGS. 2 to 4.

FIG. 2 is a block diagram showing the configuration of the multipoint communication system according to the first embodiment. In the figure, a center device 10 as a multipoint communication central control device and a plurality of communication terminals 11a to 11z are integrated with a digital integrated network (IS).
The network is connected through a DN 12. A multiplexed signal is transmitted on the line of the digital integrated network 12, and the multiplexed signal includes coded image data, coded audio data, general data (still images, data handled by a computer, and the like), and a center device. 10 and multiple communication terminals 1
Communication control data between 1a to 11z is multiplexed. Encoding of image data and audio data is performed in order to compress the information amount of the image data and audio data so that the data can be transmitted through a narrow-band communication line.

In the center device 10, a line interface unit 10a is connected to a physical
Takes an electrical interface, each communication terminal 1a-1
Form a communication path with z. The audio processing unit 10b receives and decodes each audio data from the line interface unit 10a, performs audio mixing at all points, encodes the data, and transmits the encoded data to the line interface unit 10a. Image processing unit 10
c, receives and decodes each image data from the line interface unit 10a, selects an image at one point, or synthesizes images at a plurality of points, encodes them, and sends them to the line interface unit 10a. Send. The detailed internal configuration of the image processing unit 10c will be described later with reference to FIG. The data processing unit 10d receives general data from the line interface unit 10a, switches and distributes the data, and transmits the data to the line interface unit 10a. The overall control unit 10e controls each unit of the center device 10 and controls communication with other center devices. The operation unit 10f includes an overall control unit 10e and a user operation unit 1 described later.
Take interface to 3

The user operation unit 13 displays the operation status and the like of the center device 10 to the system operator,
It is used for an initial setting operation and an operation mode designation operation performed on the center device 10 by the system operator. Since the communication terminals 11a to 11z have the same configuration, only one of them will be described with reference to FIG.

FIG. 3 is a block diagram showing the internal configuration of the communication terminal and the devices attached to it (not shown in FIG. 2). In the figure, a line interface unit 14 takes a physical / electrical interface with the digital integrated network 12. The image processing unit 15 encodes image data sent from an image input / output unit 21 described later and transmits the encoded image data to the line interface unit 14 or receives and decodes image data from the line interface unit 14 to decode the image data. 21. The audio processing unit 16 includes an audio input / output unit 22 described later.
The audio data transmitted from the line interface unit 14 is encoded and transmitted to the line interface unit 14. The audio data is received from the line interface unit 14, decoded, and transmitted to the audio input / output unit 22. The data processing unit 17 performs switching and distribution of general data transmitted from the data input / output unit 23 described later, and transmits to the line interface unit 14 or performs switching and distribution of general data transmitted from the line interface unit 14. And sends it to the data input / output unit 23. The control unit 18 controls each unit of the communication terminal,
Communication control with the center device 10 is performed. Operation unit 19
Takes an interface between the control unit 18 and a user operation unit 20 described later.

The communication terminal includes a user operation unit 20,
The image input / output unit 21, the audio input / output unit 22, and the data input / output unit 23 are connected. The user operation unit 20 displays the operation status and the like of the communication terminal to the user, and performs line operation performed by the user on the communication terminal, image processing,
It is used for an operation of designating various modes of voice processing and data processing and an operation of switching a display point. The image input / output unit 21
An image monitor and a camera. The voice input / output unit 22
A speaker and a microphone. The data input / output unit 23
It is composed of devices for the user to input and output data.

FIG. 4 is a block diagram showing the internal configuration of the image processing section 10c. The coded image data transmitted from each of the communication terminals 11a to 11z via the digital integrated network 12 and the line interface 10a is input to the image processing unit 10c. The matrix switch 24 selects one of the encoded image data sent from each of the communication terminals 11a to 11z and outputs it to the output selection switch 28. The matrix switch 24 is particularly useful when each communication terminal is used for a service of displaying an image from each specific communication terminal on its own communication terminal. At the same time, a request for this service is received from a plurality of communication terminals. In this case, the matrix switch 24 outputs the encoded image data from each specific communication terminal.

The image decoder 25 is connected to each communication terminal 11a.
-11z, each communication terminal 11
The encoded image data sent from a to 11z are respectively decoded and output to the selector switch 26. The selector switch 26 selects a required image according to the image to be synthesized by the image synthesis encoders 27a to 27n, and outputs the selected image to each of the image synthesis encoders 27a to 27n. Selection of an image to be synthesized in each of the image synthesis encoders 27a to 27n is performed in advance by an operator using the user operation unit 13 to input an image, and the overall control unit 10e and the image processing unit 10c of the center device 10 are selected.
Is transmitted to the selector switch 26 via the image control unit 29. Each of the image synthesizing encoders 27a to 27n synthesizes the transmitted images, performs encoding thereafter, and outputs the resultant to the output selection switch 28. That is, the image synthesis encoder 2
By 7a to 27n, the same number of different composite images is created.

The output selection switch 28 is provided for each of the communication terminals 11a to 11z.
z, and selects one of the coded image data of the single image transmitted from z or the coded image data of the composite image created by each of the image compositing encoders 27a to 27n, and sends it to the corresponding communication terminal. Output.

The operations of the matrix switch 24, the selector switch 26, and the output selection switch 28 are controlled by an image controller 29. Image control unit 2
9 operates according to an instruction from the overall control unit 10e (FIG. 2) of the center device 10. For example, the communication terminal 11
If the operator of the communication terminal 11a (FIG. 2) inputs a request to view the transmission image of the communication terminal 11b from the user operation unit 20 (FIG. 3), the control unit 18 (FIG. 3) of the communication terminal 11a The communication control data is sent to the overall control unit 10e (FIG. 2). Upon receiving this, the overall control unit 10e of the center device 10 sends an instruction corresponding to the request to the image control unit 29 (FIG. 4) of the image processing unit 10c.
The image control unit 29 operates the matrix switch 24 and the output selection switch 28 in accordance with the instruction to select a transmission image from the communication terminal 11b and send it to the communication terminal 11a. Alternatively, for example, communication terminal 1
Assuming that the operator 1a inputs a request to view the composite image output from the image composite encoder 27a (FIG. 4) from the user operation unit 20, the control unit 18 of the communication terminal 11a and the overall control of the center device 10 are performed. An instruction corresponding to the request is transmitted to the image control unit 29 via the unit 10e,
The image control unit 29 operates the output selection switch 28,
The synthesized image output from the image synthesis encoder 27a is selected and sent to the communication terminal 11a.

Note that the plurality of communication terminals 1a to 1z shown in FIG.
1z, the line network 2 shown in FIG. 1 corresponds to the digital integrated network 12 in FIG. 2, the multipoint communication central control device 3 shown in FIG. 1 corresponds to the center device 10 in FIG. The image synthesizing means 3a shown in FIG.
1 and the list sending unit 3b shown in FIG. 1 correspond to the general control unit 1 shown in FIG.
0e, and the image output means 3c shown in FIG.
, The image control unit 29, the matrix switch 24, and the output selection switch 28.

Next, the operation of the multipoint communication system having the above configuration will be described. FIG. 5 is an operation sequence diagram of the multipoint communication system according to the first embodiment when the reception selection service is performed.

First, the overall control unit 1 of the center device 10
0e assigns terminal numbers to the communication terminals 11a to 11z, respectively. The terminal number is a number for identifying the communication terminal, and is assigned to the center device 10 in the order in which the communication terminals 11a to 11z are connected. Here, it is assumed that terminal numbers <1> to <n> are assigned to the communication terminals 11a to 11z, respectively.
Simultaneously with this assignment, the overall control unit 10e also regards the image synthesis encoders 27a to 27n as virtual communication terminals by regarding these as virtual communication terminals.
n>.

In such a state, as shown in the sequence S1, the international standard ITU-T / H. In accordance with the standard communication control method defined in H.243, for example, the communication terminal (A) 11a
e, requesting transmission of a list of all communication terminals participating in the video conference. The overall control unit 10e of the center device 10 includes the virtual terminals assigned to the image synthesis encoders 27a to 27n together with the terminal numbers <1> to <n> assigned to the communication terminals 11a to 11z. The numbers <C1> to <Cn> are also returned to the communication terminal (A) 11a together as a terminal list. In the communication terminal (A) 11a that has received the terminal list, the control unit 18 causes the user operation unit 20 to display the terminal list.

Next, in a sequence S2, referring to such a terminal list, the communication terminal (A) 11a
The operator designates, for example, the terminal number <C1> and requests the reception selection service according to the standard communication control method. The overall control unit 10e of the center device 10 receiving this
Recognizes that the terminal number <C1> is a number assigned to the image synthesis encoder 27a, and changes the image transmitted from the image transmitted to the communication terminal (A) 11a to the requested composite image. Perform a switch. That is, the overall control unit 10e of the center device 10 first sends a terminal number <C1> related to an image newly displayed on the communication terminal (A) 11a to the communication terminal (A) 11a. Then, an instruction is given to the image control unit 29 of the image processing unit 10c to output the synthesized image output from the image synthesis encoder 27a to the communication terminal (A) 11a. Upon receiving the instruction, the image control unit 29 controls the output selection switch 28 to output the synthesized image sent from the output port 1 of the image synthesis encoder 27a to the communication terminal (A) 11a.

In the sequence S3, the communication terminal (A)
The case where the operator 11a requests the reception selection service by designating the terminal number <C2>, for example, also follows the same procedure as the sequence S2.

As described above, according to the international standard ITU-T / H.
Even in a communication terminal that operates according to the standard communication control method defined in H.243, it is possible to select a composite image and display it on its own communication terminal.

FIG. 6 is an operation sequence diagram of the multipoint communication system according to the first embodiment in the case where the broadcast terminal designation service is performed by the communication terminal to which the chair has been given.

Although not shown in FIG. 6, first, the general control unit 10e of the center device 10
Terminal numbers <1> to <n> and virtual terminal numbers <C1> to <Cn> are assigned to 1a to 11z and image synthesis encoders 27a to 27n, respectively.

In such a state, as shown in sequence S4, the international standard ITU-T / H. According to the normal conference mode of the standard communication control method defined in H.243, for example, the communication terminal (A) 11a
Requesting the chairperson of the video conference to the general control unit 10e of the center device 10 in response to the request.
e gives the chairperson to the communication terminal (A) 11a.
Here, the communication terminal to which the chair has been granted can manage the progress of the conference, but at the same time, designates a specific communication terminal (broadcasting source) and transfers images from that communication terminal to all communication terminals. The function to display simultaneously is given. According to the present invention, in the standard communication control method, a composite image can be designated as a broadcast source.

That is, in the sequence S5, referring to the terminal list, the operator of the communication terminal (A) 11a to which the chairperson has been granted, for example, checks the terminal number <C1>.
To request the broadcast source designation service according to the chairperson meeting mode of the standard communication control method. The overall control unit 10e of the center device 10 receiving this receives the terminal number <C1>
Is a number assigned to the image synthesis encoder 27a, and the communication terminals (A to Z) 11a
The switching from each image transmitted to .about.11z to the requested image is executed. That is, the overall control unit 10e of the center device 10 first newly establishes communication terminals (A to A).
Z) Terminal numbers <C1> related to images displayed on 11a to 11z are assigned to communication terminals (A to Z) 11a to 11z.
Send to Then, it instructs the image control unit 29 of the image processing unit 10c to output the synthesized image output from the image synthesis encoder 27a to the communication terminals (A to Z) 11a to 11z. Upon receiving the instruction, the image control unit 29
By controlling the output selection switch 28, the image synthesis encoder 27
The composite image sent from the output port 1 of a is output to the communication terminals (A to Z) 11a to 11z.

The sequence S6 shows a case where the operator of the communication terminal (A) 11a to which the chair has been given a request for the broadcast source designation service by designating the terminal number <C2>, for example, which is also the same as the sequence S5. Steps.

As described above, according to the international standard ITU-T / H.
Even in a communication terminal to which the chairman's right has been given, which operates according to the standard communication control method defined in H.243, it is possible to select a composite image and display it on all communication terminals.

FIG. 7 is an operation sequence diagram of the multipoint communication system according to the first embodiment when the own conference room broadcast source designation service is performed. Although not shown in FIG. 7, first, the overall control unit 10e of the center device 10
Terminal numbers <1> to <n> and virtual terminal numbers <C1> to <Cn> are assigned to the communication terminals 11a to 11z and the image synthesis encoders 27a to 27n, respectively.

In such a state, as shown in sequence S7, the international standard ITU-T / H. For example, the operator of the communication terminal (A) 11a requests the general control unit 10e of the center device 10 to send a broadcast address of the own conference room in accordance with the normal conference mode of the standard communication control method defined in H.243. This request requests that an image (meeting room image) output from the own communication terminal be simultaneously displayed on all communication terminals except the own communication terminal.

The overall control unit 10e of the center device 10 receiving this notification sends an on-air notification to the communication terminal (A) 11
Send to a. In addition, until now, communication terminals (B to Z)
Switching from each image transmitted to 11b to 11z to the requested image is executed. That is, the center device 1
First, the overall control unit 10e of the communication terminal (B-Z) 11b-1z assigns the terminal number <1> related to the image newly displayed at the communication terminal (B-Z) 11b-11z.
Send to 1z. Then, the image control unit 2 of the image processing unit 10c
9 is instructed to output the image output from the communication terminal (A) 11a to the communication terminals (B to Z) 11b to 11z. Image controller 29 receiving the instruction
Controls the matrix switch 24 and the output selection switch 28 to convert the image sent from the communication terminal (A) 11a to the communication terminals (B to Z) 11b to 11z.
Output to

Next, in the sequence S8, the center device 1
0, first, the terminal number <C related to the image newly displayed on the communication terminal (A) 11a
x> to the communication terminal (A) 11a. The terminal number <Cx> is a number assigned to the image synthesis encoder 27x, and the synthesized image output from the output port X of the image synthesis encoder 27x is a communication terminal (A) excluding the communication terminal (A) 11a. B to Z) are obtained by combining the images from 11b to 11z.

The overall control unit 10 of the center device 10
e gives an instruction to the image control unit 29 of the image processing unit 10c to output the synthesized image output from the image synthesis encoder 27x to the communication terminal (A) 11a.

As described above, according to the international standard ITU-T / H.
It is possible to display a synthesized image obtained by synthesizing images from all communication terminals except the own communication terminal on the communication terminal serving as the broadcast source of the own conference room, which operates according to the standard communication control method specified in H.243. Realize.

Next, a second embodiment will be described. Second
The configuration of this embodiment is basically the same as the configuration of the first embodiment. Therefore, in the description of the second embodiment, the configuration of the first embodiment is diverted, and only different components will be described.

FIG. 8 is a block diagram showing the internal configuration of the center device 10 according to the second embodiment. In the second embodiment, the center device 10 has a character code storage 10
g is provided. The character code storage unit 10g includes two storage areas 30, 31 as shown in FIG.
The storage area 30 stores the conference room names corresponding to the terminal numbers <1> to <m>, and the storage area 31 stores the output ports and the combination corresponding to the virtual terminal numbers <C1> to <Cn>. The annotation character of the image is stored. Storage area 30
Is stored in each of the communication terminals 11a to 11a.
The overall control unit 10e inquires of 11z about the name of each conference room, and the conference room name (character code) returned from each of the communication terminals 11a to 11z. The output ports stored in the storage area 31 are the numbers of the respective output ports of the image synthesis encoders 27a to 27n, and the annotation characters of the synthesized image are the synthesized images synthesized by the image synthesis encoders 27a to 27n. This is the name given to. The annotation character of the composite image is input in advance by the operator of the center device 10 using the user operation unit 13, and is written in the storage area 31 of the character code storage unit 10g by the overall control unit 10e.

FIG. 10 is a sequence diagram showing the operation of the second embodiment. As shown in the sequence S9, the international standard ITU-T / H. According to the standard communication control method defined in H.243, for example, the communication terminal (A) 11
a requests the total control unit 10e of the center device 10 to transmit a list of all communication terminals participating in the video conference. The overall control unit 10e of the center device 10 includes the image synthesis encoder 27 together with the terminal numbers <1> to <m> assigned to the communication terminals 11a to 11z.
virtual terminal number assigned to a to 27n <
C1> to <Cn> are also returned to the communication terminal (A) 11a together as a terminal list.

Next, in a sequence S10, referring to such a terminal list, the communication terminal (A) 11
a is based on the international standard ITU-T / H. According to the standard communication control method defined in H.243, the terminal number <1> is designated and the transmission of the conference room name is requested. Overall control unit 1 of center device 10
0e refers to the character code storage unit 10g, reads out the conference room name <AAAAAAA> corresponding to the terminal number <1>, and returns it to the communication terminal (A) 11a. Similarly, conference room names <BBBBBBB> to <XXXXXX> corresponding to the terminal numbers <2> to <m> are returned to the communication terminal (A) 11a.

In the sequence S11, referring to the terminal list, the communication terminal (A) 11a instructs the overall control unit 10e of the center device 10 to the international standard ITU-T / H.
According to the standard communication control method specified in H.243,
The transmission of the conference room name is requested by designating the terminal number <C1>. The overall control unit 10e of the center device 10 refers to the character code storage unit 10g and reads out the annotation characters <XXX, YYY, ZZZ combined display> of the combined screen corresponding to the terminal number <C1>, and calls this the conference room name. To the communication terminal (A) 11a. Similarly, terminal number <C2
> To <Cn> are also returned to the communication terminal (A) 11a as conference room names.

The names of the conference rooms returned in this way are displayed on the user operation unit 20 (FIG. 3) of the communication terminal (A) 11a when the terminal numbers <1> to <m are displayed.
>, <C1> to <Cn>. Thereby, when the operator of the communication terminal (A) 11a selects a desired image, it is possible to refer to the display of the conference room name which is easier to understand than the terminal number.

Next, a third embodiment will be described. Third
The configuration of this embodiment is basically the same as the configuration of the second embodiment. Therefore, in the description of the third embodiment, the configuration of the second embodiment is used. In the third embodiment, the configuration of the storage area of the character code storage unit 10g is different.

FIG. 11 is a diagram showing a configuration of a storage area of a character code storage unit 10g according to the third embodiment. In the third embodiment, two storage areas 32 and 33 are provided in the character code storage unit 10g. The storage area 32 is the same as the storage area 30 of the second embodiment. The storage area 32 stores conference room names corresponding to the terminal numbers <1> to <m>. In the storage area 33, output ports corresponding to the virtual terminal numbers <C1> to <Cn>, terminal numbers to be combined, and annotation characters of the combined image are stored. The output ports stored in the storage area 33 are the numbers of the respective output ports of the image synthesis encoders 27a to 27n, and the synthesis target terminal number is the source of each image synthesized by the corresponding image synthesis encoder. Is the terminal number of the communication terminal. The combination target terminal number is input in advance by the operator of the center device 10 using the user operation unit 13 according to the combination screen. The annotation character of the composite image stored in the storage area 33 is automatically generated by the overall control unit 10 e of the center device 10 based on the terminal number column of the storage area 33 and the conference room name stored in the storage area 32. Created and stored. For example, the image synthesis encoder 27 corresponding to the terminal number <C2>
The terminal number of the communication terminal to be synthesized in b is shown in FIG.
Referring to the synthesis target terminal number column of the storage area 33 of No. 1, <1>, <2>, <3>, and <4> are indicated.
The conference room names corresponding to the terminal numbers <1>, <2>, <3>, <4> are represented by A in the storage area 32 of FIG.
AA, BBB, CCC, DDD are indicated. Therefore, the overall control unit 10e of the center device 10 joins such conference room names, and finally adds a character code of "composite display" to add the annotation characters "AAA, B" of the composite image.
BB, CCC, DDD combined display "is automatically created and written in the commentary character column of the combined image in the storage area 33.

FIG. 12 is a sequence diagram showing the operation of the third embodiment. As shown in the sequence S12, the international standard ITU-T / H. 243, each communication terminal (A to X) 1
Lines 1a to 11x are connected to the center device 10, and as a result, terminal numbers <1> to <n> are assigned to the communication terminals (A to X) 11a to 11x, respectively.

Immediately thereafter, the overall control unit 10e of the center device 10 requests the communication terminals (A to X) 11a to 11x to transmit the name of the own conference room as shown in a sequence S13. On the other hand, the control unit 18 of each of the communication terminals (A to X) 11a to 11x returns the name of each conference room to the overall control unit 10e of the center device 10, respectively. The returned conference room name is written in the storage area 32 of the character code storage unit 10g for each terminal number.

In the sequence S14, the center device 1
The zero overall control unit 10e automatically creates the comment character of the composite image as described above, and writes the comment character in the comment character column of the composite image in the storage area 33 of the character code storage unit 10g.

The following sequence S15, S16, S17
Are the sequences S9, S10, S1 of the second embodiment.
1 (FIG. 10), and the description is omitted.

As described above, in the third embodiment, as compared with the second embodiment, the annotation character of the composite image is automatically created, and the creation work of the operator of the center device 10 is not required.

Next, a fourth embodiment will be described. FIG.
FIG. 3 illustrates a system configuration according to the fourth embodiment. Here, a plurality of center devices 34 to 38 are connected via a digital integrated network.
Are the master stations, and center apparatuses 35 to 38, which are slave stations, are arranged in a star shape around the master station. A plurality of communication terminals are connected to each of the center devices 34 to 38 via a digital integrated network.

The present invention described in the first embodiment is implemented in a system block composed of one center device and a plurality of communication terminals connected to the center device.
Further, in the fourth embodiment, the international standard ITU-T / H.
Within the framework of the standard communication control method specified in H.243,
It is possible to handle composite images. This will be described with reference to FIGS.

FIGS. 14 and 15 are sequence diagrams showing the operation of the fourth embodiment. FIG. 14 shows the first half and FIG. 15 shows the second half. This sequence shows an example in which a communication terminal to which a chairperson has been granted transmits a composite image to all communication terminals.

First, communication terminals V, W, X, and Y are connected to a center device 34 serving as a master station, and communication terminals A, B, C, and D are connected to a center device 35 serving as a slave station. Suppose you have Then, the image combining encoder provided with the terminal number <CX> in the center device 34 outputs an image obtained by combining the output images of the communication terminals V, W, X, and Y. The image synthesis encoder to which the terminal number <CY> is assigned is a communication terminal A,
It is assumed that an image obtained by combining the output images of B, C, and D is output.

In the sequence S18, for example, the communication terminal A connected to the center device 35 serving as the slave station requests the own center device 35 to grant the chairman's right. This is relayed to the center device 34 serving as the master station and is certified.

The communication terminal A to which the chair has been granted is:
As shown in a sequence S19, the terminal number <CX> is designated, and a broadcast transmission is requested to the center device 35 serving as a slave station. This request is relayed to the center device 34 serving as the master station. The center device 34 serving as the master station issues a switching instruction to the center devices 35 to 38 serving as slave stations, and the center device 34 and the center devices 35 to 38 cooperate with each other to connect to the center devices 34 to 38, respectively. The terminal number <CX> is notified to the communication terminal. Then, the center devices 35 to 38 receive, from the center device 34, the synthesized image created by the image synthesis encoder of the terminal number <CX> in the center device 34, and perform all communication connected to the own center devices 35 to 38, respectively. Send to terminal. Center device 3
4 also transmits the composite image to all communication terminals connected to the own center device 34.

Further, as shown in the sequence S20, the communication terminal A to which the chairman's right has been assigned has the terminal number <CY.
And requests broadcast transmission to the center device 35 serving as a slave station. This request is sent to the center device 34 serving as the master station.
Will be relayed to. The center device 34 serving as the master station issues a switching instruction to the center devices 35 to 38 serving as slave stations, and the center device 34 and the center devices 35 to 38 cooperate with each other to connect to the center devices 34 to 38, respectively. The communication terminal is notified of the terminal number <CY>. Then, the center devices 34, 36 to 38 receive, from the center device 35, the synthesized images created by the image synthesis encoder of the terminal number <CY> in the center device 35, and the respective center devices 34, 3
The data is transmitted to all communication terminals connected to 6 to 38, respectively. The center device 35 also transmits the composite image to all communication terminals connected to the own center device 35.

As described above, the plurality of center devices 34 to 3
Even in a large-scale system in which 8 are interconnected, it is possible to handle a composite image without adding any function to the communication terminal.

Next, a fifth embodiment will be described. Fifth
The configuration of this embodiment is basically the same as the configuration of the first embodiment. Therefore, in the description of the fifth embodiment, the configuration of the first embodiment will be used, and only different components will be described.

FIG. 16 is a block diagram showing the internal configuration of the center device 10 according to the fifth embodiment. In the fifth embodiment, a voice comparator 39 and a display history storage unit 40 are provided in the center device 10. First, the audio comparator 3
9 will be described with reference to FIG.

FIG. 17 is a diagram showing the internal configuration of the voice comparator 39. The voice comparator 39 sends the voice comparator 39
The level value of each voice sent from each of the communication terminals (A to Z) 11a to 11z is input. These audio level values are compared by the level comparator 39a, the communication terminal exhibiting the maximum level is specified, and the terminal number is notified to the counter control unit 39b. Counter 39c ~
39e are provided corresponding to the communication terminals (AZ) 11a to 11z, respectively.
Increments the count value of the counter corresponding to the notified terminal number by one. The above process is executed for each timing signal of a fixed cycle output by the timing circuit 39g. The counter value comparator 39f is provided in the timing circuit 3
The counter 39 has a predetermined period longer than the predetermined period of 9 g.
The respective count values of c to 39e are compared, and the terminal number of the communication terminal corresponding to the counter having the largest value is
This is notified to the overall control unit 10e of the center device 10. The communication terminal of the terminal number notified to the overall control unit 10e is, in fact, a communication terminal that frequently speaks in a video conference and has a person who speaks for a long time, and can be said to be an important communication terminal. .

Returning to FIG. 16, upon receiving this notification, the overall control unit 10e writes the terminal number into the display history storage unit 40. The storage area of the display history storage unit 40 is configured as shown in FIG. 18, and each time a notification is received from the voice comparator 39, the terminal number is written in the “latest time” column,
The terminal number previously stored in the “Latest” column is moved to the “Latest-1st” column. Similarly, until then, "Latest-
The terminal number stored in the "first time" field is repeatedly moved to the "latest-second time" field.

The overall control unit 10e automatically selects a plurality of images to be synthesized by a specific image synthesis encoder with reference to the display history storage unit 40. That is, when the number of images to be combined in the specific image combining encoder is four, the display history storage unit 40
Out of the terminal numbers stored in the "most recent" column to the "latest-third" column, and synthesizes respective images from the corresponding communication terminals.

FIG. 19 is a diagram showing, over time, a combined image combined by a specific image combining encoder based on the storage example of the display history storage unit 40 shown in FIG.
That is, first, at the timing t1, it is assumed that the communication terminal (F) 11f is detected as the communication terminal having the maximum audio level, and the communication terminals (GI) 11g to 11i have been detected at the previous timing. In this case, in a specific image synthesis encoder, images from communication terminals (FI) 11f to 11i are synthesized.
At the next timing t2, it is assumed that the communication terminal (E) 11e is detected as the communication terminal having the maximum audio level. Therefore, the image of the communication terminal (E) 11e is used in place of the communication terminal (I) 11i which is the oldest and has the highest audio level among the four, and is synthesized.
Similarly, at the next timing t3, it is assumed that the communication terminal (D) 11d is detected as the communication terminal having the maximum audio level. Therefore, the image of the communication terminal (D) 11d is used in place of the communication terminal (H) 11h which is the oldest and has the maximum audio level among the four, and is synthesized. Thus, it is assumed that the same processing is performed, and the communication terminal (A) 11a is detected as the communication terminal having the maximum audio level at the timing t6. Therefore,
Instead of the communication terminal (E) 11e which is the oldest and has the highest audio level among the four, the communication terminal (A) 1
The image of 1a is used and synthesized. Such change of the image to be synthesized is realized by the overall control unit 10e of the center device 10 giving an instruction to the image control unit 29 of the image processing unit 10c, and the image control unit 29 switching the selector switch 26 to operate.

As a result, the specific image synthesis encoder is
Based on images from important communication terminals such as the presence of a person who frequently speaks in a video conference, a composite image is created in consideration of the passage of time. Moreover, this composite image is automatically created.

Next, a sixth embodiment will be described. Sixth
The configuration of the fifth embodiment is the same as the configuration of the fifth embodiment. Therefore, in the description of the sixth embodiment, the configuration of the fifth embodiment is used. In the sixth embodiment, the configuration of the storage area of the display history storage unit 40 is different from that of the fifth embodiment.

FIG. 20 is a diagram showing a configuration of a storage area of the display history storage unit 40 according to the sixth embodiment. That is, when the reception selection service (FIG. 5) is requested from each communication terminal, the overall control unit 10e of the center device 10 stores the terminal number of the designated communication terminal (not including the composite image) in the display history. "Latest episode" of part 40
Field, and the terminal number previously stored in the “Latest” column is moved to the “Latest-1st” column. Similarly, a repetitive process of moving the terminal number stored in the “latest-first” column to the “latest-second” column until then is performed.

The overall control unit 10e automatically selects a plurality of images to be synthesized by a specific image synthesis encoder with reference to the display history storage unit 40. That is, when the number of images to be combined in the specific image combining encoder is four, the display history storage unit 40
Out of the terminal numbers stored in the "most recent" column to the "latest-third" column, and synthesizes respective images from the corresponding communication terminals.

FIG. 21 is a diagram showing, in time, a combined image combined by a specific image combining encoder based on the storage example of the display history storage unit 40 shown in FIG.
Since this is the same as the case of the fifth embodiment shown in FIG. 19, the description is omitted.

As a result, the specific image synthesis encoder is
Based on the image from the communication terminal selected and received in the video conference, a composite image is created in consideration of the passage of time. The image from the communication terminal selected for reception is likely to be an important image, and a composite screen obtained by combining a plurality of these images from the latest one is useful for a smooth conference proceeding. Moreover, this composite image is automatically created.

Next, a seventh embodiment will be described. Seventh
The configuration of the fifth embodiment is the same as the configuration of the fifth embodiment. Therefore, in the description of the seventh embodiment, the configuration of the fifth embodiment is used. The seventh embodiment differs from the fifth embodiment in the configuration of the storage area of the display history storage unit 40.

FIG. 22 is a diagram showing a configuration of a storage area of the display history storage unit 40 according to the seventh embodiment. That is, when the broadcast terminal designation service (FIG. 6) is requested from the communication terminal to which the chairperson has been granted, the overall control unit 10e of the center device 10 determines the terminal number of the designated communication terminal (the composite image is Is written in the "Broadcast source selection history" column of the "Latest time" column of the display history storage unit 40, and at the same time, the terminal number of the chairperson communication terminal that made the request is entered in the "Latest time" column. Write in the "Chairman's terminal history" column. Then, the terminal numbers stored in the "Broadcast source selection history" column and the "Chairman terminal history" column of the "Latest time" column are moved to the "Latest-1st time" column. Similarly, a repetitive process of moving each terminal number stored in the “latest-first” column to the “latest-second” column until then is performed.

The overall control unit 10e automatically selects a plurality of images to be synthesized by a specific image synthesis encoder with reference to the display history storage unit 40. That is, when the number of images to be combined in the specific image combining encoder is four, the display history storage unit 40
And the terminal number stored in the "Chairman's terminal history" column of the "Last time" column of the "Last time" column of the "Broadcast source selection history" column of the display history storage unit 40. And reads the terminal numbers stored up to "" and combines the images from the corresponding communication terminals.

FIG. 23 is a diagram showing, in time, a combined image combined by a specific image combining encoder based on the storage example of the display history storage unit 40 shown in FIG.
That is, at the timing t1, first, the communication terminal of the chair is the communication terminal (X) 11x, and the communication terminal selected by broadcasting is the communication terminal (F) 1
1f, and it is assumed that the communication terminals (G, H) 11g and 11h have been selected by broadcast at the timing before that. In this case, in the specific image synthesis encoder, the communication terminal (X) 11x and the communication terminals (F to H)
Each image from 11f to 11h is synthesized. At the next timing t2, assuming that the communication terminal of the chair is the communication terminal (A) 11a and the communication terminal selected by broadcast is the communication terminal (E) 11e, the communication terminal (A) 11a of the chair is Images and
The image of the communication terminal (E) 11e is used in place of the communication terminal (H) 11h, which is the oldest broadcast terminal among the three communication terminals already selected for broadcasting.
And two images are combined. Similarly, at the next timing t
In 3, the chair's communication terminal is the communication terminal (A)
11a and the communication terminal selected by broadcasting is the communication terminal (D) 11d, the image from the communication terminal (A) 11a of the chairman and the three communication terminals already selected by broadcasting are selected. Instead of the communication terminal (G) 11g which is the oldest and selected by broadcasting, three images using the image of the communication terminal (D) 11d are combined. Thus, the same processing is performed. At timing t5, assuming that the communication terminal of the chair is the communication terminal (A) 11a and the communication terminal selected by broadcast is the communication terminal (B) 11b,
In place of the chairman's image from the communication terminal (A) 11a and the communication terminal (E) 11e, which is the oldest and selected from the three communication terminals already selected by broadcasting,
The three images using the image of the communication terminal (B) 11b are combined.

As a result, the specific image synthesis encoder is
Based on the image from the communication terminal to which the chairman's right has been granted in the video conference and the images from the communication terminal selected by broadcasting, a composite image taking into account the passage of time is created. Each image from the communication terminal to which the chair has been granted and the broadcast selected communication terminal is likely to be an important image, especially the images from the broadcast selected communication terminal from the latest one. The composite screen composed of a plurality of sheets is useful for a smooth conference proceeding. Moreover, this composite image is automatically created.

In the seventh embodiment, the image from the communication terminal to which the chairman's right has been assigned is added to the composite image. The image from the communication terminal that is being used may not be used, and only each image from the communication terminal selected by broadcasting may be combined.

Next, an eighth embodiment will be described. 8th
The configuration of the fifth embodiment is the same as the configuration of the fifth embodiment. Therefore, in the description of the eighth embodiment, the configuration of the fifth embodiment is used. In the eighth embodiment, the configuration of the storage area of the display history storage unit 40 is different from that of the fifth embodiment.

FIG. 24 is a diagram showing a configuration of a storage area of the display history storage unit 40 according to the eighth embodiment. When each communication terminal requests the local conference room broadcast source designation service (FIG. 7), the overall control unit 10e of the center device 10 determines the terminal number of the designated communication terminal (composite images are not targeted). “Latest time” in the display history storage unit 40
Field, and the terminal number previously stored in the “Latest” column is moved to the “Latest-1st” column. Similarly, a repetitive process of moving the terminal number stored in the “latest-first” column to the “latest-second” column until then is performed.

The overall control unit 10e automatically selects a plurality of images to be synthesized by the specific image synthesis encoder with reference to the display history storage unit 40. That is, when the number of images to be combined in the specific image combining encoder is four, the display history storage unit 40
Out of the terminal numbers stored in the "most recent" column to the "latest-third" column, and synthesizes respective images from the corresponding communication terminals.

FIG. 25 is a diagram showing, over time, a combined image combined by a specific image combining encoder based on the storage example of the display history storage unit 40 shown in FIG.
Since this is the same as the case of the fifth embodiment shown in FIG. 19, the description is omitted.

As a result, the specific image synthesis encoder is
In a video conference, a composite image is created based on an image from a communication terminal designated as a broadcast source in the own conference room, taking into account the passage of time. The image from the communication terminal designated as the broadcaster of the own conference room is likely to be an important image, and a composite screen obtained by combining a plurality of these images from the latest one is useful for the smooth progress of the conference. Moreover, this composite image is automatically created.

[0091]

As described above, according to the present invention, an image synthesizing means is provided so that images sent from a plurality of communication terminals are synthesized and a synthesized image is sent out. In addition, the list sending means, the identification code corresponding to the communication terminal, the identification code corresponding to the image synthesis means,
A list is created in the same manner as the identification code corresponding to each communication terminal, and the list is sent to a plurality of communication terminals.

Thus, a plurality of communication terminals are provided by a multi-vendor, so that each communication terminal has a different operating specification and, conventionally, the international standard I
TU-T / H. Even if only the function of the communication control method of H.243 can be realized, the synthesized image can be displayed on a predetermined communication terminal only by the communication terminal selecting the identification code related to the image synthesizing means from the list.

As described above, the communication terminal selects a composite image by performing exactly the same operation as selecting a single image from a single communication terminal and displaying it on a predetermined communication terminal, as in the related art. As a result, it can be displayed on a predetermined communication terminal.

Thus, within the framework of the current standard communication control method available between the communication terminals provided by the multi-vendor, the composite image can be displayed even if the communication terminals already existing in the field are used as they are. Becomes possible.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is a configuration diagram of a multipoint communication system according to a first embodiment.

FIG. 3 is a block diagram showing an internal configuration of a communication terminal and devices attached thereto.

FIG. 4 is a block diagram illustrating an internal configuration of an image processing unit.

FIG. 5 is an operation sequence diagram of the multipoint communication system according to the first embodiment when the reception selection service is performed.

FIG. 6 is an operation sequence diagram of the multipoint communication system according to the first embodiment in a case where a broadcast terminal designation service is performed by a communication terminal to which a chairperson has been given.

FIG. 7 is an operation sequence diagram of the multipoint communication system according to the first embodiment when the own conference room broadcast source designation service is performed.

FIG. 8 is a block diagram illustrating an internal configuration of a center device according to a second embodiment.

FIG. 9 is a diagram illustrating a configuration of a storage area of a character code storage unit.

FIG. 10 is a sequence diagram showing an operation according to the second embodiment.

FIG. 11 is a diagram illustrating a configuration of a storage area of a character code storage unit according to a third embodiment.

FIG. 12 is a sequence diagram showing an operation of the third embodiment.

FIG. 13 is a diagram illustrating a system configuration according to a fourth embodiment.

FIG. 14 is a sequence diagram showing an operation of the fourth embodiment, showing the first half thereof.

FIG. 15 is a sequence diagram showing an operation of the fourth embodiment, showing the latter half thereof.

FIG. 16 is a block diagram showing an internal configuration of a center device according to a fifth embodiment.

FIG. 17 is a diagram showing an internal configuration of a voice comparator.

FIG. 18 is a diagram illustrating a configuration of a storage area of a display history storage unit.

FIG. 19 is a diagram showing a synthesized image synthesized by a specific image synthesis encoder in time sequence.

FIG. 20 is a diagram illustrating a configuration of a storage area of a display history storage unit according to the sixth embodiment.

FIG. 21 is a diagram showing a time sequence of a combined image combined by a specific image combining encoder according to the sixth embodiment.

FIG. 22 is a diagram illustrating a configuration of a storage area of a display history storage unit according to the seventh embodiment.

FIG. 23 is a diagram showing a synthesized image synthesized by a specific image synthesis encoder according to the seventh embodiment over time.

FIG. 24 is a diagram illustrating a configuration of a storage area of a display history storage unit according to the eighth embodiment.

FIG. 25 is a diagram showing a time sequence of a combined image combined by a specific image combining encoder according to the eighth embodiment.

[Explanation of symbols]

 1a to 1z Plural communication terminals 2 Network 3 Multipoint communication central controller 3a Image synthesizing means 3b List sending means 3c Image output means

Claims (13)

[Claims] 1. A communication control system for a multipoint communication system comprising a plurality of communication terminals having different operation specifications and a multipoint communication central control device connected to the plurality of communication terminals via a network. Image synthesizing means for synthesizing images sent from a plurality of communication terminals and sending out a synthesized image; and sending a list of the identification codes respectively corresponding to the plurality of communication terminals and the image synthesizing means to the plurality of communication terminals. Receiving the identification code selected from the list transmitted by the list transmission means and transmitted from the first communication terminal, and receiving the identification code corresponding to the identification code, Image output means for outputting the image sent from the communication terminal to a predetermined communication terminal. Communication control system of point communication system. 2. The communication control method according to claim 1, wherein the predetermined communication terminal is the first communication terminal. 3. The list sending means requests the plurality of communication terminals to send a character code for identifying the own communication terminal, and receives a character code sent from each communication terminal. Means, a character code received by the receiving means, and a character code named by an operator for the image synthesizing means,
2. A communication control system for a multipoint communication system according to claim 1, further comprising: character code sending means for sending to said plurality of communication terminals in association with said identification code. 4. The list sending means requests the plurality of communication terminals to send a character code for identifying the own communication terminal, and receives a character code sent from each communication terminal. Means, from among the character codes received by the receiving means, extract a character code of a communication terminal of a transmission source of each image synthesized by the image synthesizing means, and combine the extracted character codes to form the image. A character code creating unit that automatically creates a character code corresponding to the combining unit; a character code received by the receiving unit; and a character code created by the character code creating unit, which is associated with the identification code. A character code sending means for sending the character code to the plurality of communication terminals. Control system. 5. A chairperson granting means for granting a chairman right to a communication terminal that has requested a chairmanship of a video conference,
2. The communication terminal according to claim 1, wherein the first communication terminal is an all communication terminal when the first communication terminal is requested and granted to the chairperson granting means.
The communication control method of the multipoint communication system described in the above. 6. When the first communication terminal requests the image of the own communication terminal to be transmitted to all communication terminals other than the own communication terminal, the first communication terminal transmits the image from the image synthesizing unit to the first communication terminal. A transmitting unit that transmits the transmitted image, wherein the first communication terminal requests the image of the own communication terminal to be transmitted to all communication terminals other than the own communication terminal; The communication control method according to claim 1, wherein the communication terminals are all communication terminals except the first communication terminal. 7. The image synthesizing means comprises: a detecting means for detecting, at a predetermined timing, a communication terminal outputting a maximum level of sound from the plurality of communication terminals; Recording means for continuously recording the identification code of the communication terminal detected for each, reference to the recorded content of the recording means, a selection means for selecting a predetermined number of communication terminals, and each of the selected by the selection means The communication control method for a multipoint communication system according to claim 1, further comprising: synthesizing means for synthesizing an image sent from the communication terminal into one screen. 8. The image synthesizing means, when a service that allows a communication terminal to select an image to be displayed on its own communication terminal is applied, records an identification code of the communication terminal corresponding to the selected image. Means, referring to the contents continuously recorded by the recording means, and selecting means for selecting a predetermined number of communication terminals; images transmitted from the respective communication terminals selected by the selection means on one screen. The communication control method for a multipoint communication system according to claim 1, further comprising: combining means for combining. 9. The image synthesizing means, wherein a chairman of a video conference is given to the second communication terminal, and all images transmitted from the third communication terminal are communicated based on an instruction from the second communication terminal. A recording means for recording an identification code of the third communication terminal when a service for broadcasting to the terminal is applied; and a predetermined number of communication 2. The multipoint communication system according to claim 1, further comprising: a selecting unit configured to select a terminal; and a combining unit configured to combine an image transmitted from each communication terminal selected by the selecting unit into one screen. Communication control method. 10. The image processing apparatus according to claim 1, wherein the combining unit combines the image sent from each of the communication terminals selected by the sorting unit and the image sent from the second communication terminal into one screen. 10. The communication control method for a multipoint communication system according to item 9. 11. The image synthesizing means, when a service for broadcasting the image output from the second communication terminal from the own communication terminal to all the communication terminals except the own communication terminal is applied, the second image forming means includes: Recording means for recording an identification code of the communication terminal of the communication terminal; selecting means for selecting a predetermined number of communication terminals by referring to the contents continuously recorded by the recording means; and each communication selected by the selection means. 2. A communication control method for a multipoint communication system according to claim 1, further comprising: synthesizing means for synthesizing an image sent from the terminal into one screen. 12. The communication terminal according to claim 7, wherein said selecting means preferentially selects a newly recorded communication terminal by referring to contents continuously recorded by said recording means. The communication control method of the multipoint communication system according to any one of the above. 13. A system block comprising a plurality of communication terminals having different operation specifications and a multipoint central control unit connected to the plurality of communication terminals via a circuit network. In a communication control system of a multipoint communication system in which point communication central control devices are connected to each other via a circuit network, provided in each multipoint communication central control device and sent from a plurality of communication terminals in the own system block. Image synthesizing means for synthesizing an image and sending out a synthesized image; and a plurality of communication terminals provided in each multipoint communication central controller and corresponding to the image synthesizing means of the own multipoint communication central controller. A list sending means for sending a list of identification codes to each communication terminal in all system blocks, and a setting at each multipoint communication central control device. Selected by referring to the list sent by the list sending means,
Receiving the identification code sent from the first communication terminal,
When the communication terminal or the image synthesizing unit corresponding to the identification code belongs to the own system block, an image transmitted from the communication terminal or the image synthesizing unit corresponding to the identification code is output to a predetermined communication terminal.
Image output means, provided in each multipoint communication central control device, selected by referring to the list sent by the list sending means,
Receiving the identification code sent from the second communication terminal,
When the communication terminal or the image combining means corresponding to the identification code belongs to another system block, the output of the communication terminal or the image combining means corresponding to the identification code is output from the first image output means of the other system block. And a second image output means for receiving an image and outputting the image to a predetermined communication terminal.