JPH07274148A - Video telephone conference system among multi-spots - Google Patents

Abstract

PURPOSE:To simultaneously display the moving pictures of all attendants by allocating the maximum value of a transmission speed standard value as transmission speed for dynamic image transmission/reception and allocating the maximum transmission speed standard value if a remaining band which can be allocated exists. CONSTITUTION:When a conference attendant B asks for speaking to a chairman terminal equipment 100a, the speaking designation part 107 of the equipment 100a designates a speaker for a conference attendant terminal equipment 110b. At the same time, a dynamic image transmission speed designation part 105 allocates maximum transmission speed to the terminal equipment 110b of the attendant B in a range which does not exceed transmission speed calculated from the maximum transmission speed of a using network 130 and the number of the attendants. At that time, transmission speed which can be used for the other terminal equipments 110c and 110d is calculated from the maximum transmission speed of the network 130 which is used and from transmission speed allocated to the terminal equipment 110b and the change of transmission speed is indicated to the other terminal equipments 110c and 110d by the indication part 105. Thus, the attending attitude of the other conference attendants is recognized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multipoint videophone conference system, and more particularly to a moving image between all conference terminal devices including a moderator terminal device even if the transmission band of the network used is limited. The present invention relates to a multipoint video conference system capable of transmitting and receiving information.

[0002]

2. Description of the Related Art Conventionally, a multipoint videophone conference system is, for example, an ITU (International Telecommunication System).
(s) Union: International Telecommunication Union) Recommendation H. 231 (Multipoi
nt control units for audiovisual systems using dig
ital channels up to 2 Mbit / s), and H.264. 243 (Pr
ocedures for establishing communication between th
ree or more audiovisual terminals using digital ch
annels up to 2 Mbit / s), each call is connected from each conference terminal device to the multipoint control unit, and the voice controls all the voices of the conference participants by the multipoint control unit. Then, the conferences are simultaneously transmitted to each conference terminal device, and only one movie image selected from the conference terminal device or the moderator terminal device is simultaneously transmitted to each conference terminal device to hold a conference.

[0003]

However, in the above-mentioned conventional multipoint video conference system, the voices of the conference participants can be transmitted and received at the same time and with a constant quality, but the moving image is used. Due to the limitation of the transmission band of the network, only one moving image can be simultaneously transmitted to the terminal devices of the conference participants.

For this reason, each conference participant cannot see the state of the conference participant other than the displayed moving image from the screen, and, for example, the conference participant who is presently speaking to the terminal device of the moderator. When the moving image is displayed, there is a problem that the moderator does not notice even if another conference participant makes a new request to speak by raising his hand or the like.

In this case, the other conference participants who want to request a new speech will obstruct the speech of the conference participant who is currently speaking by voice and display the intention of the speech.

An object of the present invention is to construct a multi-point videophone conference system, even if a network having a limited transmission band is used, by displaying the moving images of all the conference participants in each conference terminal device. It is to provide a multipoint video-phone conference system capable of simultaneously displaying a video image of a specific conference participant and displaying the video image of a specific conference participant separately from the video images of other conference participants.

[0007]

Among the inventions disclosed in the present application, a brief description will be given to the outline of typical ones.
It is as follows.

That is, a multipoint videophone for connecting a moderator terminal device and a plurality of conference terminal devices via a network having a limited transmission band, and transmitting and receiving voice and moving images between the terminal devices to hold a conference. In the conference system,
The moderator terminal device implicitly divides the maximum transmission rate of the network by the current number of conference participants including the moderator, and sets the maximum transmission rate standard value that does not exceed the transmission rate of the result of the division to the conference participation state. The first process of allocating to each of the conference terminal devices as a transmission rate for moving image transmission / reception, and the conference terminal device of the conference participant in the speaking state can allocate a transmission rate higher than the currently assigned transmission rate. A transmission rate allocating means is provided for checking whether or not a band exists and, if it exists, a second process for allocating the maximum transmission rate standard value.

[0009]

According to the above means, when constructing a multipoint videophone conference system using a network having a limited transmission band, the moderator terminal device determines the maximum transmission rate of the network as a moderator. A first value is assigned to each conference terminal device in the conference participation state as a moving image transmission / reception transmission speed, and the maximum value of the transmission speed standard value that does not exceed the transmission speed of the result of the encryption is included The processing and the conference terminal device of the conference participant in the speaking state are checked whether or not there is a remaining bandwidth that can be assigned a transmission rate higher than the transmission rate currently being assigned. Since the second processing for allocating the transmission speed standard value is performed, the moving images of all the conference participants can be simultaneously displayed on each conference terminal device, and the speaker and the other conference participants can be distinguished from each other. Can Kill.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a system configuration diagram showing the overall configuration of an embodiment of a multipoint videophone conference system according to the present invention.

In FIG. 1, reference numeral 100a is a moderator terminal device, 101 is a TV camera for capturing a moving image of the moderator A, 102 is a moving image encoding unit for encoding and transmitting the captured moving image, and 103 is A display device, 104 is a moving image decoding unit that decodes the received moving image, 105 is a conference participation receiving unit that receives a terminal device that participates in the conference, and 106 manages the transmission speed of the network to be used, and is a conference participant terminal. A moving image transmission rate assigning unit that assigns a moving image transmission rate to a device, 107 a speaker designating unit that designates a speaker, 108 a central processing unit (hereinafter referred to as CPU), 1
Reference numeral 09 denotes a main storage device (hereinafter referred to as MS) that stores various programs.

Reference numeral 110b is a conference participant terminal device of the conference participant B, 111 is a TV camera, 112 is a display device,
Reference numeral 113 is a moving picture coding unit, 114 is a moving picture decoding unit, 1
Reference numeral 15 is a moving image transmission rate change receiving unit for changing the transmission rate assigned from the moderator terminal device 100a, and 116 is C
PU 117 is MS.

Reference numerals 120a and 120b are line control units, and 130 is a network as a transmission line. In this embodiment, ISD is used.
A wide area communication network such as N (Integrated Service Digital Network) is assumed.

Reference numeral 110c is a conference participant terminal device of the conference participant C, and 110d is a conference participant terminal device of the conference participant D.

In the present embodiment, the maximum transmission rate will be used instead of the maximum transmission band of the network 130 used.

Also, the TV camera 101 in the moderator terminal device 100a and the conference participant terminal device 110b,
111, display devices 103 and 112, CPUs 109 and 11
6 and MS 110, 117 can be implemented using existing industrial TV cameras, monitor TVs, CPUs and memories.

The moving picture coding units 101 and 113 and the moving picture decoding units 104 and 114 can be realized by existing picture coding and decoding techniques.

Then, the conference participation reception unit 10 according to the present invention.
5, moving picture transmission rate assigning section 106, speaker designating section 1
07 and the moving image transmission speed change accepting unit 115 are stored as programs in the MS 109 and MS 117, respectively, and the present invention stores these programs in the CP.
It is realized by the execution of U109 and U116.

FIG. 2 is an explanatory diagram for explaining the state of the conference participants on the screen of the display device of the moderator terminal device in the multipoint videophone conference system of this embodiment.

In this embodiment, the case where there are four conference participants will be described.

FIG. 2 shows the screen of the display device 112 of the moderator terminal device 100a. FIG. 2A shows a screen at the start of the conference, and the moderator terminal device 10 of the moderator A.
On the screen of the display device 103 of 0a, one conference participant B
Is displayed.

FIG. 2B shows a screen when the conference participant C subsequently participates in the conference, and FIG. 2C shows a screen when the conference participant D participates in the conference. Yes, the state in which the conference participant B is speaking is displayed.

Here, the transmission rate (hereinafter referred to as the required transmission rate) required to simultaneously display the moving images of all the conference participants on all the terminal devices including the moderator is given by the following equation.

[0025]

## EQU00001 ## Required transmission rate = maximum transmission rate / (number of conference participants + 1) ... Equation (1) Note that "+1" in Equation (1) represents the moderator.

Further, as shown in FIG. 2C, when the conference participant B is in the speaking state, the moderator terminal device 100a.
In order to distinguish it from other conference participants, if there is a margin in the transmission rate calculated from the maximum transmission rate of the network 130 used and the current number of conference participants, the conference participants of the conference participant B are The terminal device 110b is assigned a higher transmission rate than the other conference participant terminal devices 110 (c, d), but if there is no margin, the current transmission rate is maintained.

That is, when the transmission speed has a margin, the screen of the conference participant B, who is the speaker, is assigned a required transmission speed for displaying a more natural movement, and the other conference participants C, The screen of D is assigned a transmission speed of displaying an image close to a still image.

In FIG. 2, the size of the moving image of the conference participant B who is the speaker is made larger than the sizes of the moving images of the other conference participants. This is for the purpose of clearly indicating the conference participant B who is the speaker, and in fact, the sizes of the moving images of all the conference participants may be the same.

FIG. 3 is a flowchart showing signal transmission / reception between the conference participant terminal device and the moderator terminal device of this embodiment.

As shown in FIG. 3, first, the conference participant B
However, at the time of joining the conference, the conference participant terminal device 110b
From the moderator terminal device 100a, a request for participation in the conference is made (step 301).
The conference participation reception unit 106 of a has the conference participant terminal device 11
The transmission rate calculated from the equation (1) is instructed to 0b (step 302).

Next, when the conference participant C participates and similarly requests to participate in the conference (step 303), the moderator terminal device 100a determines the number of conference participants as in the case of the conference participant B. According to the above, the transmission rate calculated from the equation (1) is instructed to the conference participant terminal device 110c of the conference participant C (step 304).

At this time, the transmission speed instructed to the conference participant terminal device 110c has already been changed to the conference participant terminal device 110b.
If it is different from the transmission rate instructed in step 1, the conference participant terminal device 110c is instructed, and at the same time, the conference participant terminal device 110b is instructed to change to a new transmission rate (step 305).

Similarly, when the conference participant D participates in the conference, the moderator terminal device 110a is similarly requested to participate in the conference (step 306), and the transmission rate according to the number of participants in the conference is allocated (step 306). Step 307).

Next, the conference participant B receives the moderator terminal device 10
When a request is made to 0a (step 308), the speaker specifying unit 107 of the moderator terminal device 100a specifies a speaker for the conference participant terminal device 110b (step 309), and at the same time, the moving image is displayed. Transmission rate instruction unit 105
However, the largest transmission is made to the conference participant terminal device 110b of the conference participant B who is the speaker within a range not exceeding the maximum transmission rate of the network 130 being used and the transmission rate calculated from the number of conference participants. Assign a speed (step 310).

At this time, the moving image transmission speed instruction unit 105
From the maximum transmission rate of the network 130 being used and the transmission rate assigned to the conference participant terminal device 110b, the usable transmission rate for the other conference participant terminal devices 110 (c, d) is calculated, An instruction to change the transmission rate is issued to the other conference participant terminal devices 110 (c, d) (step 311).

Thus, the moderator terminal device 100a
A process of allocating a required transmission rate for simultaneously displaying moving images of all the conference participants on each terminal device based on the maximum transmission rate of the network 130 used and the number of conference participants, and a speaker and other conference participants. And a process of assigning a transmission speed for distinguishing the person from the person.

Next, a method of allocating a transmission rate according to the number of conference participants and speakers will be described.

FIG. 4 is a diagram showing an example of various management tables managed by the moderator terminal device of this embodiment.

In FIG. 4, reference numeral 400 denotes a moving image transmission rate management table for managing the transmission rate of moving images that can be transmitted from the maximum transmission rate of the network 130 used.
Reference numeral 10 is a network transmission rate management table that manages the maximum transmission rate of the network 130 to be used. In this embodiment, the maximum transmission rate is 1536 kbit / s, and these are managed as fixed data.

Reference numeral 420 is a current conference participant number management table for managing the number of persons currently participating in the conference.
Reference numeral 0 denotes a current moving picture transmission rate management table for managing the transmission rate of moving pictures during a conference, which are managed as variable data.

In this embodiment, in order to simplify the reference processing of these various tables, a value of 0 kbit / s is set as the minimum value at the beginning of the moving picture transmission speed management table 400.

Next, the procedure for the moderator terminal device 100a to determine the transmission speed of the moving image of each conference participant terminal device 110 (b, c, d) using the data of these various tables will be described. To do.

FIG. 5 is a flow chart showing a processing procedure for determining the transmission speed of the moving image of each terminal device in this embodiment.

As shown in FIG. 5, first, from the contents of the current conference participant number management table 420, the number of conference participants in the current conference is set to "SANKASUU" (the number of participants), and the network transmission rate management table 410. The contents of "SA
Save to "IDAI" (maximum) (step 5)
01, 502).

Here, the value of "SANKASUU" does not include the number of moderators, and represents the number of all conference participants except the moderator.

Furthermore, "SAIDAI" is changed to "SANKA".
Network 13 to use the quotient divided by "SUU + 1"
It is saved in "HITSUSUYO" (required) as a required transmission rate of 0 (step 503).

[+] Of "SANKASUU + 1"
1 ”is the number of moderators, and the network 13 used.
In 0, the moving images of all the conference participants including the moderator,
Moderator terminal device 100a and all conference participant terminal devices 1
This is a step of calculating a required transmission rate for displaying simultaneously on 10 (b, c, d).

Next, the moving picture transmission speed management table 400
Search with the value saved in the above "HITSUSUYO",
The maximum moving image transmission speed is calculated within the range of the value not exceeding "HITSUSUYO", and is set to "SOKUDO" (speed) (step 504).

Here, if the calculated "SOKUDO"
Is equal to 0 kbit / s (step 50
5: YES). If a new conference participant is admitted, the transmission speed assigned for moving image transmission will be exceeded, so that the new conference participant is refused to participate in the conference (step 506).

The obtained "SOKUDO" is 0 kbit /
If it is not equal to s (step 505: No), a new conference participant to the conference is admitted, and the contents of the current moving image speed management table 430 are set to “GENSOKUDO” (current speed) (step 507). This setting "GE
NSOKUDO ”and“ SOKU ”obtained in step 504.
"DO" is compared (step 508).

As a result of this comparison, if "GENSOK
If "UDO" and "SOKUDO" are not equal (step 508: No), the obtained "SOKUDO" is set as a new moving image transmission rate in the current moving image transmission rate management table 430 (step 509), and each of them is set. To the conference participant terminal devices 110 (b, c, d) as a new moving image transmission rate (step 510).

If "GENSOKUDO" and "SOK"
If the "UDO" is equal (step 508: Yes), a new conference participant can be recognized while maintaining the current transmission rate, so that only the terminal device newly joining the conference can receive this "SOKUDO". The value of "" is designated (step 511).

Here, "GENSOKUDO",
Uppercase alphanumeric characters such as "SOKUDO" are values set in the work area for calculation.

FIG. 6 is a flowchart showing a processing procedure in which the moderator terminal device of this embodiment controls the transmission speed of the moving image of the speaker.

As shown in FIG. 6, first, the contents of the current moving image transmission speed management table 430 are changed to "GENSOKUD".
"O" (step 601), and if there is a conference participant who is currently speaking, save the moving image transmission rate to "GENSOKUDO" for the conference participant terminal device, for example, the conference participant terminal device 110b. An instruction is issued to change to the specified value (step 602).

Next, the number of participants in the current conference is read from the current conference participant number management table 420, and "SAKA
"SUU" and the contents of the network transmission rate management table 410 are saved in "SAIDAI" as the maximum transmission rate assigned to the moving image (steps 603 and 604).

Next, "GEN" is added to "SAKASUU-1".
The value multiplied by “SOKUDO” is saved in “SAIDAI”, and from “SAIDAI” saved in step 604,
"GENSOKUDO" is added to this "SAKASUU-1"
The value obtained by subtracting the value multiplied by is set to "KYOYOU" (permissible) (step 605) to investigate how much transmission capacity remains in the currently used network 130.

Then, the moving image transmission speed management table 40
The value described in 0 is set to the above-mentioned "KYOYO
The value of "U" is searched, the maximum moving image transmission speed is found within the range of "KYOYOU", and "SOKUDO" is calculated.
(Step 606), and the set "SOKU
The value of “DO” is compared with the value of “GENSOKUDO” (step 607).

If the set value of "SOKUDO" and the value of "GENSOKUDO" are equal (step 607: Yes), the moving image transmission speed of the speaker cannot be increased more than the present speed, and therefore the processing is performed. finish.

If not equal (step 607: N
o) Since it is possible to increase the moving image transmission speed higher than the current moving image transmission speed, the moving image transmission speed is changed with respect to the terminal device requesting to speak the value of “SOKUDO”, for example, the conference participant terminal device 110b. (Step 60)
8).

At this time, another conference participant terminal device 110
For (c, d), a transmission rate less than or equal to the transmission rate used by the speaker is calculated and an instruction to change the transmission rate (not shown).

The present embodiment will be described below with reference to the procedures of FIGS. 5 and 6 by using the specific numerical values shown in the various management tables of FIG.

The number of participants in the conference is 4 including the moderator, and the transmission speed of the network 130 used is 6
4 kbit / s, 128 kbit / s, 384 kbit
/ S and 768 kbit / s, the maximum transmission speed that can be used for moving image transmission is 1536 kbit / s
And

First, when the conference participants are the moderator A and the conference participant B, the required transmission rate is 768 kbi.
Since it is t / s, a high-quality moving image can be displayed on each terminal device.

Next, when the third conference participant C participates in the conference, the moderator terminal device 100a sets the transmission speed to the conference participant terminal device 110b at 768 kb.
While instructing to change from it / s to 384 kbit / s, for the conference participant terminal device 110c,
It is instructed to transmit the moving image at the transmission speed of 384 kbit / s.

When the conference participant D participates in the conference and the number of conference participants becomes four, the moderator terminal device 100
a is the above formula (1) “maximum transmission rate / (number of participants +
1) ”, 1536 ÷ (3 + 1) = 384 kbi
Although the transmission rate of t / s is obtained, if this transmission rate is assigned to each terminal device, more than the current participants cannot join the conference, so the conference participant terminal device 110
128k lower transmission rate than (b, c, d)
Instruct to send a moving image at bit / s.

When a specific conference participant, for example, conference participant B, requests to speak, step 60 in FIG.
Formula of 5

[0068]

[Formula 2] 1536− (4-1) × 128 = 1152k using “maximum transmission rate− (number of participants−1) × current rate”
Since the transmission rate of bit / s is obtained, 384 kbit / s in the moving image transmission rate management table 400 shown in FIG.
The conference participant terminal device 110b is instructed to transmit the moving image at a transmission rate of s or 768 kbit / s.

Also in this case, the conference participant terminal device 110b
On the other hand, if the transmission rate of 768 kbit / s is assigned, it means that more than the current participants cannot participate in the conference, and therefore the moving image is instructed to be transmitted at the transmission rate of 384 kbit / s which is one rank lower.

As can be seen from the description of this embodiment,
In the multipoint video conference system according to the present invention, from the maximum transmission rate of the network 130 to be used,
A transmission rate according to the number of participants in the conference can be assigned to each conference participant terminal device 110 (b, c, d).

Thus, the moving images of all the conference participants participating in the conference can be simultaneously displayed on each conference participant terminal device 110 (b, c, d) including the moderator terminal device 100a. Therefore, the behavior of the conference participant who wants to speak next can be easily recognized.

For the speaker, for example, the conference participant terminal device 110b of the conference participant B, step 608.
As described above, another conference participant terminal device 110
By assigning a higher transmission rate than (c, d), it is possible to distinguish the other conference participant from the conference participant B who is the speaker.

In this embodiment, the speaker designating section 107 is used.
Although the example in which is prepared in advance as a program has been described, this specifying method can be performed, for example, by the moderator terminal device 100.
The display screen of a may be clicked with a pointing device such as a mouse, or a method of inputting numbers or symbols of conference participants using an input / output device such as a keyboard.

Further, in this embodiment, the network 13
Although the explanation has been made assuming that a wide area integrated digital network such as ISDN is assumed to be 0, the network 130 is a LAN (Local Are
a Network), in the case of a narrow area network,
By managing the number of frames of moving images transmitted and received per second instead of the transmission rate, the same effect as that of the present embodiment can be obtained.

[0075]

The effects obtained by the typical ones of the inventions disclosed in this application will be briefly described as follows.
It is as follows.

(1) When constructing a multipoint videophone conference system, even if a network with a limited transmission band is used, the moving images of all the conference participants are simultaneously displayed on each terminal device. can do.

By (2) and (1), it is possible to recognize the behavior of the conference participant who wants to speak next and the attitude of other conference participants to participate in the conference.

(3) A specific conference participant, for example, currently,
A speaker and another conference participant are distinguished by assigning a higher transmission speed to the terminal device of the conference participant who is speaking compared to the transmission speed of the moving image of another conference participant. be able to.

[Brief description of drawings]

FIG. 1 is a system configuration diagram showing an overall configuration of an embodiment of a multipoint videophone conference system according to the present invention.

FIG. 2 is an explanatory diagram for explaining a state of conference participants on the screen of the display device of the moderator terminal device in the multipoint videophone conference system of the present embodiment.

FIG. 3 is a flowchart showing signal transmission / reception between a moderator terminal device and a conference participant terminal device according to the present embodiment.

FIG. 4 is a diagram showing an example of various management tables managed by the moderator terminal device of the present embodiment.

FIG. 5 is a flowchart showing a processing procedure for determining a moving image transmission rate of each terminal device in the present embodiment.

FIG. 6 is a flowchart showing a processing procedure in which the moderator terminal device of the present embodiment controls the transmission speed of the moving image of the speaker.

[Explanation of symbols]

100a ... moderator terminal device, 101, 111 ... TV camera, 102, 113 ... Moving image coding unit, 103, 112
... Display device, 104, 114 ... Moving image decoding unit, 105
... conference participation receiving unit, 106 ... moving image transmission rate assigning unit, 107 ... speaker designating unit, 108, 116 ... central processing unit (CPU), 109, 117 ... (MS), 110
(B, c, d) ... Conference participant terminal device, 115 ... Transmission rate change receiving unit, 120a, b ... Line control unit, 130 ... Network.

Claims (1)

[Claims] 1. A multipoint videophone for connecting a moderator terminal device and a plurality of conference terminal devices via a network having a limited transmission band, and transmitting and receiving voice and moving images between the respective terminal devices to hold a conference. In the conference system, the moderator terminal device implicitly divides the maximum transmission rate of the network by the current number of conference participants including the moderator, and the maximum transmission rate standard value that does not exceed the transmission rate of the result of the division. Is assigned to each conference terminal device in the conference participation state as the transmission rate for moving image transmission / reception, and the conference terminal device of the conference participant in the speaking state is set to a transmission rate equal to or higher than the currently assigned transmission rate. It is characterized by comprising a transmission rate allocating means for checking whether or not there is an allocatable remaining band and, if there is, a second process for allocating the maximum transmission rate standard value among them. Point-to-point videophone conference system.