JPS62108689A - Inter-multiple points television conference system - Google Patents

Abstract

PURPOSE:To display plural images simultaneously without increasing a facility cost, such as a transmission line by connecting each conference room with one line of image and sound line, and performing the multiplex transmission of the images at plural points. CONSTITUTION:When a request for a conference between multiple points is issued, a call is placed from a terminal similarly as a telephone call, and each conference device and an inter-multiple points conference control device are connected with each other. In conference, each of conference devices 101-104 picks up the images of attendants at its own room, and also, collects voices and sends them to an intermultiple points conference control device 121 through transmission lines 111-114. At the inter-multiple points conference control device 121, picture signals in two conference rooms in discussion with each other at that time out of the picture signals sent from each conference room are selected, and the picture signals 200 and 201 in the two conference rooms are multiplexed and one television screen signal is constituted. At such a time, the picture signals 200 and 201, the upper and the lower parts of which are eliminated, are synthesized as the images long from side to side.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field to which the Invention Pertains) The present invention connects conference rooms at a plurality of distant locations through a television image line and an audio line. The present invention relates to a multipoint video conferencing system that makes it possible to perform the following tasks.

(Prior Art) A video conference system is known in which a conference is held between remote locations by connecting the remote locations through a television image line and an audio line and mutually transmitting and receiving images and voices of conferees.

These video conference systems include a normal point-to-point video conference system that targets meetings between two locations, and a multi-point video conference system that targets conferences between a plurality of locations.

Of these, the latter point-to-point conference method conventionally involves connecting multiple points in a mesh-like manner with video and audio lines and displaying images of each conference room in parallel, and a method in which a point-to-point conference control device is installed within the communication network. , a method is known in which images from each point are once collected in this point-to-point conference control device, and images of the requested point are selected and distributed to each point.

However, the former method has the drawback that it requires multiple video and audio lines, both subscriber lines and relay lines, to connect each point in a mesh-like manner, which increases the equipment cost (1-1) and the service cost.

In addition, in the latter method, only one ground image can be seen at each point in time in each conference room, and phase t7. During debates, images of both parties cannot be viewed at the same time, making it difficult to grasp the reactions of the debaters, making it difficult to use.

(Object of the Invention) An object of the present invention is to provide an easy-to-use multipoint video conference system that can display a plurality of images simultaneously without increasing equipment costs such as transmission lines.

(Structure of the Invention) The present invention connects each conference room with a single image and audio line and uses technology to multiplex transmit images from multiple locations. This is a method that allows you to view images of.

(Embodiment) FIG. 1 is a block diagram showing a system configuration in an embodiment of the present invention, in which 101 to 104 refer to a video conference device that extracts and transmits video and audio from one's own room, and displays and reproduces received images and audio; 111 to 14 are transmission lines for bidirectionally transmitting video and audio provided corresponding to the video conference devices 101 to 104, 120 is a video and audio exchange, and J21 is an inter-point conference control device.

Figure 2 is a diagram showing the principle of the multiplexing method for image signals.
0 and 201 are image signals before multiplexing, and 202 are image signals after multiplexing.

Next, the operation of the point-to-point conference method according to the method of the present invention will be explained using FIGS. 1 and 2.

When a point-to-point conference request occurs, a call is made from the terminal in the same way as a normal telephone or the like, and each conference device and the point-to-point conference control device are interconnected. During a meeting, each conference device 101-1
04 captures images of conference participants in its own room, collects sounds, and sends them to the point-to-point conference control device 121 through transmission circuits 111 to 114.

The point-to-point conference control device 121 selects the image signals of the two conference rooms that are currently in mutual discussion among the image signals sent from each conference room, and displays the television images of these two conference rooms as shown in FIG. Signals 200 and 201 are multiplexed to form a television one-screen signal 202.

Detection of a conference room during a discussion can be performed by comparing the audio levels from each conference room using the point-to-point conference control device.

At this time, video conference room images generally have multiple people lined up horizontally, and compared to normal TV images, the main image area is horizontally long, and the top and bottom areas reflect the ceiling and conference desk. Therefore, even if the top and bottom parts are cut, it is often sufficient as a conference image.

For this reason, when multiplexing image signals, the top and bottom portions of each of the image signals 200 and 201 are removed, only the portion where a person is shown horizontally is extracted, and the vertical width of each image signal is reduced to 1/1/2 of that of a normal television signal. Make it so that it becomes 2. After doing this, for example, if the vertical phase of the image signal 201 is delayed by 1/2 frame compared to the vertical screen phase of the image (M No. 200) and the two signals are superimposed, a composite multiplexed image signal 201 is generated. can be obtained.

The multiplexed image signal 202 obtained in this way is an image for one frame of a normal television image signal, and is transmitted to each of the conference devices 101 to 104 through one transmission line 111 to 114.
It is possible to transmit through.

Each conference device] 01 to 104 displays the multiplexed image signal sent in this way as a TV image signal, or separates it into two screens by performing the reverse operation to the multiplexing process. , displayed on two television receivers. This allows each conference room to view images of two conference rooms that are currently being discussed at the same time.

On the other hand, as for audio, the audio from each conference room is collected by a microphone and transmitted to the multi-point conference control device 121 through transmission lines 111 to 114.

The long point-to-point conference device 121 mixes the voices from other conference rooms, excluding the voices from each conference room's own room, and sends the mixture back to each conference room. This allows each conference room to hear all audio from other conference rooms.

Another method of processing audio is to exclude the audio from the own conference room from among the audio from each conference room, and select only a certain number of audio from the highest level in terms of audio level, for example, from two or three conference rooms. It is also possible to mix the information and send it back to each conference room.

In this way, if there are many conference points in a long point-to-point conference, for example, if there are more than 5 points, mixing the audio from all the points will increase the noise level of the audio and make it very difficult to hear. Or, due to acoustic coupling between microphones and speakers in each conference room, multiple acoustic loops may occur through the transmission path, which may easily cause ringing and make it difficult to hear. I can do it.

The multipoint conference control device 121 processes video and audio signals in a bipedal manner, allowing each conference room to simultaneously view the images of the two conference rooms currently being discussed and listen to the discussion status. I can do things.

Therefore, compared to the conventional method of switching and displaying only one image of the conference room where the speaker is present, this method has the feature that it is easier to understand the state of the meeting.

In addition, in the above explanation, a method was shown in which the images of the two conference rooms under discussion are selected as the two conference room images to be multiplexed in the long point-to-point conference device. It is also possible to select, multiplex, and combine signals based on requests from the rooms, and to control the transmission to each conference room individually. 2 more
It is also possible to allocate one screen to the image of the conference room where the speaker is present, and the other screen to the image of the conference room where the moderator is present.

By doing this, images of the two conference rooms under discussion can be viewed at the same time, and an image of a desired conference room can be viewed, increasing the usability of the conference system.

Next, a method of implementing each device that enables the above point-to-point conference operation will be explained.

FIG. 3 is a block diagram showing the configuration of the video conference devices 101 to 104, in which 300 is a TV camera, 301 is a VIK (
302 is a video transmission amplifier, 303 is a video reception amplifier, 304 is a video separation unit, 305 is a synchronization phase promotion unit, 306 is a V synchronization phase delay unit, 307 and 308 are displays Monitor, 309 is an audio transmitting amplifier, 310 is an audio receiving amplifier, 311 is a microphone, 31
2 is a speaker, and 313 is an operating device.

FIG. 4 is a block diagram showing the configuration of the point-to-long point conference control unit, in which 400 is a VIK separation unit, 401 is a control unit, 402 is a synchronization phase adjustment unit, 403 is a channel switching unit, 404 is an audio mixing unit, and 405 is a This is an audio level detection section.

Figure 5 is a diagram explaining the VIK signal in the television signal.
00 is the vertical synchronization signal section, 501 is the VIK signal section, 502
indicates the period of one video frame.

FIG. 6 is a diagram explaining the multiplexing method of image signals, (a),
(b) is two video signals to be multiplexed, (c) is a video signal after multiplexing, and A and r3 are video signals showing a human part at the center of the frame of the two video signals.

FIG. 7 is a diagram explaining the separation operation of the multiplexed composite signal.
a) is a multiplexed composite signal, (b) and (C) are two video signals after separation, and A and B are signals of a human image portion in the video signal.

Next, the configuration and operation of the video conference device and point-to-point conference control device according to the system of the present invention will be explained using FIGS. 3 to 7.

The video conference devices 101 to 104 have a configuration as shown in FIG.
Images of people in the meeting are captured by a television camera 300.

It passes through the VIK inserter 301 and the transmitter 101 and is sent out to the point-to-point conference control device.

At this time, the VIK signal insertion unit 301 receives the number of the other party's conference room that the conference device desires to display from the operating device 313, and inserts a code corresponding to the number into the television video signal.

Here, the VIK signal is interrupted by a control signal inserted in the vertical blanking period of the television signal with a pulse waveform like 501, as shown in Figure 5, and this control signal does not affect the video signal. This is a signal that can convey control information to the control end. The conference room number that the conference room that is inserted as the VIK that the conference room wishes to display will be transmitted to the point-to-point conference control device.

Also, the audio in the conference room is collected by the microphone 311 and sent to the point-to-point conference control device 121 through the audio transmission amplifier.

The point-to-point conference control device has a configuration as shown in FIG. 4, and video signals sent from each conference device first enter the v'rK signal detection section 400. Here, the number of the other conference room that each conference room wishes to display is extracted from the video signal as the XK signal.

This information is sent to the control unit 401 and used to control the synthesis of video signals.

The video signal synthesis operation is performed as follows. That is, the video signal sent from each conference room enters the synchronous phase adjustment section 402 after VIK detection. Here, the phase of each video signal can be adjusted to any desired phase by once accumulating the video signals sent from each conference room and then reading them out.

The channel switching unit 403 reads out the image of the target conference room from the phase adjustment unit 402 at the following phase based on the conference room number desired to be displayed from each conference room.

In other words, as shown in Fig. 6, two video signals (a) are multiplexed.
), the central parts A and B showing the human part of (b) are continuous,
It is read out at a phase timing that becomes one normal television video signal (c). That is, by switching the two video signals A and B at the center of one frame period and adding a synchronization signal in accordance with the switching, a series of television signals (c) can be synthesized.

On the screen, this composite television signal takes the form of a composite of two horizontally long conference room images separated at the center of the screen, as shown in FIG.

At the time of this synthesis, the following procedure can be used to multiplex images of two conference rooms containing discussants instead of the conference rooms designated to be displayed from each conference room.

That is, when the point-to-point conference control unit receives audio signals from each conference room, the audio level detection unit 405 compares the audio levels of each conference room. As a result, the top two conference rooms with the highest audio levels can be identified, and the video of those two conference rooms can be multiplexed using the same method as described above.Here, the level comparison and detection of the audio in each conference room is performed using normal audio. It is clear that this can be easily achieved using technology.

The video signals multiplexed and combined as described above are sent back to each conference device via the communication network. - Regarding the audio system, the audio sent from each conference room is mixed by the audio mixing unit 4'04, excluding the audio from the own room, and is sent back to each conference room.

Next, regarding the reception system of the conference device, the following configuration and operation are performed.

That is, when the conference apparatus shown in FIG. 3 receives the multiplexed video signal shown in FIG.

The separation unit 304 separates the upper half A and the lower half B of the image based on the vertical synchronization signal phase of the video signal, and separates each into the upper half A and the lower half B as shown in FIG.
As shown in b) and (c), the V synchronization phase promotion unit 305. V synchronous phase delay section 30
6 accelerates, delays and adds the synchronization phase.

The video signals separated in this manner are sent to display monitors 307 and 308, respectively, and displayed.

In this case, the fact that the video signal is displayed at the center of the display screen will be clear from the rewrite of the synchronizing signal phase.

Regarding audio, the signal sent from each point-to-point conference device through the mixer 14 is reproduced by the speaker 312 via the audio receiving amplifier 310.

That is, it can be seen that the above-mentioned multi-screen simultaneous display operation can be performed by the conference device and the point-to-point conference control device having the configurations shown in FIGS. 3 and 4.

(Effects of the Invention) As explained above, according to the method of the present invention, each conference device can transmit and display images of multiple conference rooms simultaneously using only one line, so it is possible to easily use multiple conference rooms without increasing transmission costs. It has the advantage of being able to implement point-to-point meetings.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the system configuration in an embodiment of the present invention, FIG. 2 is a diagram showing the principle of the image signal multiplexing method, FIG. 3 is a block diagram showing the configuration of the video conference device, and FIG. The figure is a block diagram showing the configuration of the long point-to-long point conference conference control unit, FIG. 5 is a diagram explaining the VIK signal in the television signal, FIG. 6 is a diagram explaining the multiplexing method of image signals, and FIG. FIG. 3 is a diagram illustrating a separation operation of multiplexed signals. 101.102,103,1.04...TV conference device, 111.112,113,11.4...Transmission line,
120... Video and audio exchange, 121... Point-to-point conference control device, 200.201... Image signal before multiplexing, 202...
- Image signal after multiplexing, 300... Television camera, 301... Insertion section in VI', 302... Video transmitting amplifier, 303... Video receiving amplifier, 304... Image separating section, 305. ... V-synchronization phase promotion section, 306 ... V-synchronization phase delay section, 307.308 ... Display monitor, 309 ... Audio transmission amplifier, 310 ... Audio reception amplifier, 311 ... Microphone, 3
12... Speaker, 313... Controller, 400...
- VIK separation section, 401... Control section, 402... Synchronization phase adjustment section, 403... Channel switching section, 404... Audio mixing section, 405... Audio level detection section, 500... Vertical synchronization signal section, 501-VIK signal section, 502... One frame period of video. Patent Applicant Nippon Telegraph and Telephone Corporation Figure 1, Figure 2 Figure 5 5o○ 500-t! a) 111i-'p501-VI
Kization P 502 Ice statue 1 frame viewing Figure 6 Figure 7

Claims (3)

[Claims] (1) A television camera that captures images of people in a conference room, a video transmission amplifier that sends the video signal to a transmission path, a reception amplifier that receives the video signal sent from the transmission path, and a display device that displays the video signal; A microphone that collects conference audio,
A television consisting of an audio transmitting amplifier that sends audio signals to a transmission path, an audio receiving amplifier that receives audio signals, an audio reproduction speaker, an operator that instructs the conference room image, and a VIK insertion unit that inserts the instruction signal into the video signal. A conference device, a VIK detection unit that separates the transmission path and VIK signals, a phase adjustment unit that adjusts the phase of video signals sent from multiple conference rooms, a channel switching unit that switches and combines multiple video channels, and multiple conference rooms. The multipoint conference control device consists of an audio signal level comparison section that compares the levels of audio signals sent from multiple conference devices, and an audio mixing section that mixes the audio. A multi-point TV characterized by having the function of multiplexing the video signals of two conference rooms into the upper half and lower half of one screen, forming a video signal for one television line, and sending it back to each conference room. Conference method. (2) Multiplexing video signals with a multipoint conference control device 2
Claim (1) characterized in that images of two conference rooms under discussion are selected and multiplexed as one conference room video signal based on a comparison of audio signal levels from each conference room.
Multipoint video conferencing method described in Section 1. (3) Multiplexing video signals with a multipoint conference control device 2
A multi-point connection according to claim (1), characterized in that videos of two conference rooms instructed based on a display request control signal from each conference room are multiplexed as one conference room video signal. Video conference method.