JPH0983987A - Inter-multi-point communication controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a cheap inter-multi-point communication controller by providing video encoding parts which output encoded composite video data generated by encoding composite video data to time division multiplexing separation parts and whose number is smaller than that of the time division multiplexing separation parts. SOLUTION: The controller is provided with the time division multiplexing separation parts 2a to 2d, video decoding parts 3a to 3d, a control part 6, a video preparing part 4 and a video encoding part 50. The video encoding part 50 outputs encoded composite video data generated by encoding composite video data to the time division multiplexing separation parts 2a to 2d. As a conference picture prepared by the video preparing part 4 is common to the single conference then, the video encoding part on an equipment side 50 encode- processing this common conference picture is singly provided within an equipment 1a. Namely it is unnecessitated to provide the video encoding part 50 for encoding a video signal consisting of analog signals for each video terminals 10a to 10d and the cheap equipment 1a is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inter-multipoint communication control device for implementing a multi-point video conference using, for example, a video conference terminal.

[0002]

2. Description of the Related Art FIG. 5 shows, for example, JP-A-63-2769.
FIG. 13 is a configuration diagram showing a video conference system configured based on a conventional example described in Japanese Patent No. 38. As shown in FIG. 5, this video conference system includes a multipoint communication control device (hereinafter, referred to as a device) 1 and a video conference terminal (hereinafter, referred to as a terminal) 10 provided at each point (four places in FIG. 5). It consists of and. Note that the subscripts a to d added to the reference numerals will be omitted unless otherwise specified.

As shown in FIG. 5, the device 1 is a device-side time division device that separates a recording signal, which will be described later, into video data, audio data, and other data, and, conversely, combines these data and performs signal synthesis. Demultiplexer (hereinafter TDM on the device side
2, a device side image decoding unit 3 that performs the above-described image data decoding process, and an image creation unit 4 that combines the output images output and displayed on the terminal at each point.

The device 1 also includes a device-side video encoding unit 5 for encoding the conference video data of the video conference video created by the video creation unit 4.

The device-side video coding unit 5 has a coding frame memory for storing each video data in time series therein, and a portion of a pixel in which a motion compensation amount is transmitted or an operation is performed as described later. Only the data is encoded to reduce the amount of communication data.

Further, the device 1 is provided with a control unit 6 for giving a video production command to the video production unit 4 based on control data from the chairman terminal which will be described later.

The device-side TDM 2, the device-side video decoding unit 3, the video creating unit 4, and the device-side video encoding unit 5 are provided according to the number of terminals 10 connected to the device 1.

On the other hand, as shown in FIG. 6, the terminal 10 provided at each point has a recording means 11 for recording the pattern of the conference (video, audio, etc.), a recording means 11 composed of a recording device, and the like. The AD converter 12 for AD-converting the video data in the recorded signal recorded by the means 11, and the format type of the video data in the recorded signal are digital NTSC (Na
An input data format converter 13 is provided for converting from a National Television System Committee format to a digital CIF (Common Intermediate Form) format.

Here, the input data format conversion unit 1
3 also has a frame memory (however, a frame memory for format conversion) inside thereof as in the device side video encoding unit 5. Then, the digital NTSC format is converted to the digital CIF format by performing a thinning process or the like as described later.

Further, the terminal 10 is provided with a terminal side coding section 14 for coding the video data converted by the input data format conversion section 13 into the digital CIF format, and the coded video from the terminal side coding section 14 is also included. data,
Terminal side time division demultiplexing unit 15 (hereinafter referred to as time division demultiplexing unit for demultiplexing audio data and other data, and demultiplexing conference video data, conference audio data, and other data from the time division multiplexed data sent from the device 1 , TDM on the terminal side).

Further, the terminal 10 decodes the conference video data separated from the video conference signal by the terminal-side TDM 15, and decodes the conference video data by the terminal-side decoding unit 16 and the conference-side video data decoded by the terminal-side decoding unit 16 in the digital CIF format. Output data format conversion unit 17 that performs format conversion from a digital to NTSC format, a DA conversion unit 18 that DA converts the conference video data that has been format converted by the output data format conversion unit 17, and an analog video composite signal from the DA conversion unit 18. Is provided with an output display unit 19 configured by, for example, a display.

Here, the output data format conversion unit 1
Similarly to the input data format conversion section 13, the reference numeral 7 also has a format conversion frame memory therein. Then, the digital CIF format is converted to the digital NTSC format by performing an interpolation process as will be described later.

Reference numeral 20 is a general term for communication lines connecting the device 1 and the terminal 10.

Next, the operation of the video conference system using the apparatus 1 thus constructed will be described with reference to FIG.

Consider a case where terminals 10a to 10d at four points participate and hold one video conference. When the video conference is held, the terminals 10a to 10d each perform the same operation, but the held conference always has a chairperson terminal that presides over the conference. The chairman terminal is the terminal 10a
As an example, the case where the conference information is transmitted from the terminal 10a to the multipoint control unit 1 will be described.

When a video conference is held, the audio data in the analog recording signal recorded by the recording unit 11a of the terminal 10a provided at the point A and including audio data and video data is AD-converted. 12a is digitally converted, and the input data format conversion unit 13 is further used.
sent to a.

As described above, the digital video data recorded by the recording means 11a and further AD-converted by the AD converter 12a has a data format of the digital NTSC system adopted in the ordinary television broadcasting system. There is. On the other hand, a digital CIF format format is adopted for video encoding processing in a video conference. Both types differ from each other in the number of vertical and horizontal pixels of video data per screen.

Therefore, the input data format conversion unit 1
3a performs format conversion of the video data from the digital NTSC format to the digital CIF format. Format conversion from digital NTSC format to digital CIF format
For example, with respect to video data for each screen configured by the digital NTSC system, which is stored in a format conversion frame memory (not shown) in the input data format conversion unit 13a in time series, a digital CI is selected from each screen.
This is performed by using a known image processing technique such as extraction processing for thinning out pixel portions corresponding to the F format display image. Then, the input data format conversion unit 13a
Outputs the video data converted into the digital CIF format to the terminal side encoding unit 14a.

Next, the terminal side encoding section 14a is stored in the encoding frame memory (not shown) provided therein in a time series order for each screen, and the predetermined time intervals after conversion into the digital CIF format are performed. Video data of
Compare each other in chronological order. Then, if the image on the screen is accompanied by so-called motion compensation of simply moving in parallel, the amount of motion compensation, and if there is a difference from the previous screen (there is a motion in the screen), Only the operated pixel portion is encoded and sequentially output from the terminal-side TDM 15a via the communication line 20a.

As described above, instead of sending the video data of the entire one screen for each screen, sending only the information of the pixel portion having the motion in the screen is the sending sent via the communication line 20a. This is to reduce the amount of data. Therefore, with respect to the portion having no motion, the previous pixel portion is used as it is in the image.

The encoded video data from the terminal 10a, which has been encoded, is multiplexed by the terminal-side TDM 15a as described above with the audio data and other control data for each data type, and output. The data is input to the device 1 via each communication line 20a.

The control data is created by a system console (not shown), and the control data specifies the channel used in each conference and the participating terminals participating in the same conference. This designation can be made only by the chair terminal. In this way, the pattern of the conference at the point A is input from the terminal 10a to the multipoint communication control device 1 as a recording signal.

In the device 1, the encoded recording signal from the terminal 10a received in time division via the communication line 20a is
The device-side TDM 2a separates the image data into audio data, control data, and the like. Of these, the image data is sent to the device-side image decoding unit 3. Further, the control data is sent to the control unit 6, and based on this control data, the video creation unit 4 forms the same conference as will be described later in the terminal 10a.
The video data from 10 to 10d are combined with each other.

Here, the terminals that make up the same conference are designated, and this designation is made only by the control data from the chairman terminal, the control data is sent to the control unit 6, and is further output to the video creating unit 4. To be done. Then, the video creation unit 4 performs processing such as reduction of video data from the terminals 10a to 10d that form the same conference and composition of reduced video data of the same conference, which will be described later, based on the control data.

The device-side video decoding unit 3a decodes the coded video data for each screen of the conference from the terminal 10a, and then sends it to the video creating unit 4 (other terminals 10b-1 to 10b-1).
The decoding process is similarly performed for the video data in the recording signal from 0d. ).

In the image creation unit 4, the terminals 10a to 10a that make up the same conference are based on the control data from the control unit 6.
A conference video to be output and displayed commonly to each terminal is created from the video data transmitted from d. The video creation is performed in the order of a video reduction process for fitting the video data on one screen and a video composition process for collecting the reduced video on one screen.

First, the image reduction processing is performed by reducing the areas of the images from the above four terminals to 1/4.
That is, regarding the reduction processing frame memory in the image creating unit 4 in which the image data for each screen converted into the digital CIF format is stored in time series, the length is set to 1 in both the vertical and horizontal directions from each screen. Pixel portions corresponding to 1/4 reduced video compressed to / 2 are thinned out and extracted. Therefore, for each screen, a pixel number of 1/4 is extracted from the pixels of the original image, and an image reduced to 1/4 is created.

The image synthesizing process is performed by connecting the four reduced images created as described above to each other to synthesize one output display image. The combination into one screen is performed for each screen at a predetermined time interval in chronological order. In this way, the output display unit 19 in FIG.
Combined conference video data that fits on one screen as shown in a to 19d is created.

Since the conference video data created as described above is output to the terminals 10a to 10d, respectively, the device-side video coding units 5a to 5d corresponding to the respective terminals.
(For example, the device side video encoding unit 5a corresponds to the terminal 10a). Device-side video encoding units 5a to 5d
Then, the same process as the encoding process in the terminal side encoding unit 14a in the terminal 10a is performed.

The device-side video encoding units 5a to 5d compare the conference video data stored in the internal encoding frame memory for each screen in chronological order with each other in chronological order. Then, as described above, the motion compensation or only the pixel portion having the motion is encoded, and the terminals 10a to 10d are respectively transmitted via the terminal side TDMs 15a to 15d.
In order.

The reason why only the information of the pixel portion having the motion in the conference video data is transmitted in this way is to reduce the amount of transmission data transmitted via the communication lines 20a to 20d as described above. . Therefore, with respect to the portion having no motion, the previous pixel portion is used as it is for the conference video data.

Then, the encoded conference video data is multiplexed by the device 1 with the audio data previously separated from the video data by the device side TDMs 2a to 2d and other data to form an encoded conference signal. Are output in a time-division manner for each type of data, and the communication lines 20a to 20
It is input to the terminals 10a to 10d via d.

With respect to the voice data, the voice of each point is synthesized as conference voice data by a voice synthesizing section (not shown) by using a known voice processing technique, and the synthesized voice data is multiplexed from the device 1 to each terminal. 10a-1
It is output to 0d.

The encoded video conference signal from the device 1 is transmitted by the terminal side TDM 15a at the terminal 10a.
Meeting audio data for each type of data in time division,
Separated into other control data. Of these, the conference video data is decrypted by the terminal-side decryption unit 16a and further transmitted to the output data format conversion unit 17a.

Therefore, the output data format conversion unit 1
7a performs format conversion of the conference video data from the digital CIF format to the digital NTSC format. Digital CIF format to digital N
Format conversion to TSC format, for example,
Digital CIs stored in a frame memory for format conversion (not shown) in the format conversion unit in chronological order
Regarding the conference video data for each screen configured by F method,
This is performed by using a known image processing technique such as pixel interpolation processing so as to correspond to a display image of digital NTSC format from each one screen. Then, the output data format conversion unit 17a outputs the conference video data converted into the digital NTSC format to the DA conversion unit 18a.

The DA converter 18a converts the conference video data into an analog signal, and the conference video data is output to the output display unit 1.
The output is displayed from 9a. In this way, the video of each video conference from the recording means 11a to 11d at each point is output to the output display units 19a to 19d as an output display screen at each point, for example, as shown in FIG.

[0037]

As described above, in the conventional apparatus 1, the terminal 10a is used to hold the video conference.
It is necessary to respectively provide device-side video encoding units 5a to 5d for encoding the analog conference video signals for each of the terminals -10d, and the frame memories required for the encoding process also correspond to the terminals 10a to 10d, respectively. Therefore, there is a problem that the device 1 becomes expensive.

The present invention has been made to solve the above problems, and a video encoding unit for encoding a video signal of a conference composed of analog signals is provided in each multipoint communication control device for each terminal. An object is to obtain an inexpensive multipoint communication control device that eliminates the need.

[0039]

A multipoint communication control device according to the present invention inputs multiplexed terminal information from a plurality of video terminals to separate terminal video data from the terminal information, and a code to be described later. A plurality of time-division demultiplexing units that multiplex conference video data and other data to send to a video terminal, a plurality of video decoding units that decode terminal video data from a plurality of video terminals, and terminal information. The control unit that outputs a control command based on the included control data, the image creation unit that creates the conference video data by combining the decoded data decoded by the plurality of video decoding units based on the control command, and the combined video data. The number of video coding units is smaller than the number of time division demultiplexing units for outputting the coded composite video data generated by coding to the plurality of time division demultiplexing units.

Further, the video encoding unit is provided in accordance with the type of communication capacity with the video terminal.

Further, the video encoding unit is provided in accordance with the number of multipoint communication simultaneously performed in parallel between different video terminal groups of a plurality of video terminals.

[0042]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1. FIG. 1 is a diagram showing the configuration of a multipoint-to-point communication control apparatus according to Embodiment 1 of the present invention. In FIG. 1, the same or corresponding parts as those of the conventional example are designated by the same reference numerals, and the description thereof will be omitted. In the first embodiment, it is assumed that four terminals 10a to 10d participate in one video conference as in the conventional example.

For one conference, it is sufficient if the conference images common to the conference can be prepared for the terminals 10a to 10d that form the conference. Since the conference screen generated by the image creating unit 4 is common to the one conference, the device-side image encoding unit 50 that encodes this common conference image.
Is provided in the device 1a in common for one conference. Then, the encoded common conference video is distributed and supplied to each terminal participating in this conference.

In the apparatus 1a thus constructed, as in the conventional case, the conference recording signals such as video and audio are generated from each of the terminals 10a to 10d and sent to the apparatus 1a. Then, decryption processing is performed inside the device 1a,
The operation of conference video creation processing and conference video encoding processing is
The procedure is similar to that of the conventional example.

The apparatus-side video encoding unit 50 provided in common for this conference encodes and encodes the conference video data common to this conference by the technique using the frame memory as shown in the conventional example. Meeting video data is sent to terminals 10a-10
device-side TDMs 2a to 2d each corresponding to d
Respectively.

As in the conventional case, the device side TDMs 2a to 2d are provided.
Each of the terminals 10a to 10d by multiplexing audio data and other control data with the conference video data.
Output to The operation of performing a predetermined output process in the terminals 10a to 10d and outputting and displaying the conference video on the output display units 19a to 19d is the same as in the conventional example, and the description thereof will be omitted.

According to the first embodiment, the multiplexed terminal information is input from a plurality of video terminals to separate the terminal video data from the terminal information, and at the same time, the coded combined video data described later and other data are separated. Included in the terminal information are a plurality of time division demultiplexing units 2a to 2d that are multiplexed and sent to the video terminal, a plurality of video decoding units 3a to 3d that decode the terminal video data from the plurality of video terminals 10a to 10d, respectively. A control unit 6 which outputs a control command based on the control data
A plurality of video creating units 4 that combine the decoded data decoded by the plurality of video decoding units 3a to 3d based on a control command to generate composite video data, and a plurality of coded composite video data generated by encoding the composite video data. Time division demultiplexing units 2a-2
Since the number of video encoding units 50 is smaller than the number of time division demultiplexing units 2 to be output to d,
It is only necessary to provide a smaller number of device-side image encoding units 50 than the number of terminals 10a to 10d, and it is necessary to provide each image terminal 10 with an image encoding unit 5 for encoding an image formed of an analog signal. Is eliminated, and an inexpensive multipoint communication control device can be obtained.

Embodiment 2 In the first embodiment, the terminal 10
It is assumed that the data communication capacities of the data communication performed between the a to 10d and the multipoint control unit 1a via the communication lines 20a to 20d are the same, but the terminals forming one video conference. There may be a case where the communication capacities having different communication capacities are mixed in the side (there are plural kinds of communication capacities).

FIG. 2 is a diagram showing the configuration of the multipoint-to-point communication control apparatus according to the second embodiment of the present invention. In FIG. 2, parts that are the same as or correspond to those in the conventional example and the embodiment are given the same reference numerals, and description thereof will be omitted. In FIG. 2, it is assumed that also in the second embodiment, four terminals participate to hold one video conference. Then, among these terminals 10a to 10d, the terminals 10a and 10b have a communication capacity of 64 kbps, and the terminal 10
c and 10d have a communication capacity of 128 kbps, and the device 1 is connected via the communication lines 20a, 20b and 20c, 20d, respectively.
It shall communicate with b.

Since terminals forming one video conference include those that communicate with two kinds of communication capacities having different communication capacities, the two kinds of device side corresponding to each communication capacity are provided inside the device 1b. Video coding units 50a and 50b are provided. The device side video encoding unit 50a has a communication capacity of 64 kbps.
Corresponding to the terminals 10a and 10b, and the device-side video encoding unit 50b has a communication capacity of 128 kbps.
It corresponds to c and 10d.

The operation of the multipoint control device thus configured will be described. The recording signals output from the terminals 10a to 10d are transmitted to the device-side TDM 2a to
2d, and the video data is extracted from the recording signals by the device side TDMs 2a to 2d. The extracted video data is sent to the device-side video decoding units 3a to 3 respectively.
is input to d. The control data from the chair terminal is also extracted and sent to the control unit 6.

After that, the video data is decoded by the device-side video decoding units 3a to 3d as in the conventional case. Then, based on the control data sent from the chairman terminal to the control unit 6, one video conference video data is created for each time series from the decoded video data of these four conferences (video 1
/ 4 reduction, conference video composition). Then, the created conference video is input to the device-side video encoding units 50a and 50b corresponding to the two types of communication capacities of the terminal, respectively.

The device side image encoding units 50a and 50b perform respective encoding processes using the frame memory as described above. The conference video data after the encoding process is supplied to the device-side TDM 2 corresponding to the terminals connected to the device-side video encoding units 50a and 50b, respectively.

The conference video data supplied to each of the device side TDMs 2a to 2d is multiplexed with audio data and other control data and sent to the terminals 10a to 10d, and each terminal 10 performs the same processing as the conventional one. Output the conference video.

According to the second embodiment, the device-side video coding units 50a and 50b are provided for each type of communication capacity performed between the video conference terminals 10a to 10d and the multipoint communication control device 1b. Therefore, even if terminals having different communication capacities are mixed in terminals forming one video conference, the video conference can be performed.

Embodiment 3 Although the case where one video conference is held is shown in the first embodiment, a plurality of video conferences may be simultaneously held in parallel. FIG. 3 is a diagram showing the configuration of the multipoint-to-point communication control apparatus according to Embodiment 3 of the present invention. In FIG. 3, those parts which are the same as or correspond to those of the conventional example and the embodiment are designated by the same reference numerals, and description thereof will be omitted.

In FIG. 3, the apparatus-side video encoding unit 50 has the apparatus 1 for each conference to be held (for each conference presided over by the chair terminal).
It is provided within the range of the number of meetings that can be held in parallel at the same time due to the processing capacity of c. In FIG. 3, device-side video encoding units 50A to 50C are provided, and up to three conferences can be held in parallel at the same time. Then, the device-side video encoding units 50A to 5 provided for each conference to be held.
0C is used properly according to the conference to be held.

Further, the device side image encoding units 50A to 50C
The input switching unit 21 is provided on the input side of the device, and based on the control data sent from the chairman terminal to the control unit 6, the conference video data output from the video creating unit 4 is sorted for each conference and the device side video encoding is performed. It is adapted to be input to the sections 50A to 50C.

Further, the device side image coding units 50A-50
An output switching unit 22 is provided on the output side of C, and based on the control data sent from the chairman's terminal to the control unit 6, the conferences encoded by the device side image encoding units 50A to 50C corresponding to each conference. The video data is distributed to each terminal participating in the conference, and the device-side TDM 2a-
It is designed to be output to the terminals participating in each video conference via 2d.

The operation of the multipoint control device thus configured will be described. A conference held as described above always has a chairperson's terminal that presides over the conference. Here, two conferences A and B are held simultaneously in parallel, and terminal 1
0a is the conference A, and terminal 10b is the conference B.

From the chairman terminal 10a, the pattern of the conference at the point a is input to the device 1c as a recording signal together with other control data signals. On the other hand, from the chairman's terminal 10b, point b
The pattern of the conference at is input to the device 1c as a recording signal together with other control data signals. In these control data, the channel used in each conference and the terminals participating in each conference are specified.

The control data sent from the chair terminals 10a and 10b are separated by the device side TDMs 2a and 2b, respectively, and input to the control unit 6. The control unit 6 outputs the respective control data to the image creation unit 4, the input switching unit 21, and the output switching unit 22, respectively.

On the other hand, similarly to the above-mentioned conventional example, the patterns of the conference at each point are input to the apparatus-side TDM 2 as recording signals from the terminals other than the chairperson's terminal that participate in each conference. The recording signal input to the device-side TDM 2 is separated into video data, audio data, and other data, and the video data is decoded by the device-side video decoding unit 3 corresponding to each device-side TDM 2 one by one. Further, it is input to the screen creation unit 4.

In the image creating section 4, the image screen is reduced and the image screens are combined as in the conventional case. Here, as described above, the conference A centering on the chair terminal 10a, the chair terminal 10
Since the conference B centering on b is held in parallel at the same time, the images from the terminals participating in each conference are reduced at a predetermined rate for each conference, and each conference is divided into each conference. The screens of the participating terminals are combined at the same time, and the images of each conference are created in time series.

The created conference video at each conference is output from the video creating unit 4 and input to the input switching unit 21. The input switching unit 21 distributes and outputs the conference video data to the device-side video encoding unit 50 corresponding to each conference based on the control data described above.

In each of the device side image encoding units 50,
Encoding processing using a frame memory similar to the conventional one is performed for each conference and output to the output switching unit 22. The output switching unit 22 outputs the video data for each conference to the device-side TDM 2 corresponding to the terminals participating in each conference on a one-to-one basis based on the control data described above.

As in the conventional case, each device side TDM2
The conference video data supplied to the
It is multiplexed with other control data and sent to each terminal.
Then, each terminal performs the same processing as the conventional one and outputs and displays the conference video. The voice data is subjected to a predetermined voice synthesis process as in the conventional example.

According to the third embodiment, the device side image encoding units 50A to 50C are provided for each of the image conferences held simultaneously in parallel, and the device side image of the conference image data is output based on the output of the control unit 6. The input switching unit 21 that switches the input to the encoding units 50A to 50C, and the time-division multiplexing device 1 from the device-side image encoding units 50A to 50C based on the output of the control unit 6.
Since the output switching unit 22 for switching the output to the device is provided, it is possible to reduce the processing load of the device-side video encoding unit 50 when a plurality of video conferences are held simultaneously in parallel.

Fourth Embodiment The multipoint communication control apparatus according to the third embodiment has shown the example in which a plurality of conferences can be held at the same time. However, the communication capacity as shown in the second embodiment is set in the terminals forming each conference. In some cases, terminals with different numbers are mixed.

FIG. 4 is a diagram showing the structure of the multipoint-to-point communication control apparatus according to the fourth embodiment. In FIG. 4, the same or corresponding parts as those of the conventional example and the embodiment are designated by the same reference numerals. The description is omitted.

As shown in FIG. 4, the chairperson terminal of the conference A is set to 1
0a, the chairperson terminal of the conference B is 10b, and simultaneously, in parallel, each conference of the conferences A and B includes terminals that process with two types of communication capacities of 64 kbps and 128 kbps as shown in the second embodiment. It is assumed that

Then, for encoding processing of each conference, device-side image encoding units 50Aa and 50Ab for processing of conference A and device-side image encoding unit 50 for processing of conference B are performed.
Ba and 50Bb are provided respectively. Of these, the device-side video encoding units 50Aa and 50Ba have a communication capacity of 64 kb.
The device side video encoding units 50Ab and 50Bb correspond to a communication capacity of 128 kbps.

Further, the input switching unit 21 is provided on the input side of the device side image encoding unit 50, and the conference image data output from the image forming unit 4 is distributed for each conference and the device side image encoding unit 50Aa, Input is made to 50Ab, 50Ba, and 50Bb.

Further, the device side image encoding units 50Aa, 5
Output switching units 22a to 22d are provided corresponding to 0Ab, 50Ba, and 50Bb, respectively, and a device-side video encoding unit 50A corresponding to each communication capacity of each conference.
The conference video data encoded by a, 50Ab, 50Ba, and 50Bb is distributed to each terminal participating in the conference, and is input to the terminals participating in each conference via the device-side TDMs 2a to 2d corresponding to each terminal. Has become.

Then, the control data from the chairman's terminal is sent to the control section 6, and based on this control data, from the video data sent from each terminal, for each conference in the screen creating section 4 as will be described later. Creation of conference video data, input device 21 to conference video data device side video encoding unit 50A
a, 50Ab, 50Ba, 50Bb, and the encoded conference video data from the output selecting means 22 is distributed to each conference participating terminal.

In the device 1d thus configured, the video image creating section 4 creates a video image screen for each conference based on the control data described above, as in the second embodiment. Then, the conference video data respectively created are input by the input switching unit 21 to the device-side video encoding units 50Aa, 50Ab, 5Ab, 5Ab, 5Ab, 5Ab according to the conference based on the control data.
It is output to 0Ba and 50Bb.

Device-side video coding units 50Aa, 50Ab,
In 50Ba and 50Bb, encoding processing using a frame memory similar to the conventional one for each communication capacity as in the third embodiment is performed and output to each output switching unit 22.
The output switching units 22a to 22d, based on the control data,
The conference video data is output to the device-side TDM 2 connected to the terminals participating in each conference in a one-to-one correspondence.

Each device-side TDM 2 multiplexes the audio data and other data with the video data and outputs the multiplexed data to the terminals. The respective terminals perform the above-described predetermined processing to display the output.

According to the fourth embodiment, the video conferencing terminal 10 in the video conference held simultaneously in parallel by the device side video encoding units 50Aa, 50Ab, 50Ba, 50Bb.
Is provided for each type of communication capacity to be performed between the multipoint communication control device d1 and the multipoint communication control device d1, and the device side video encoding units 50Aa, 50Ab, 50B of the conference video data are output based on the output of the control unit 6.
a, an input switching unit 21 for switching the input to 50Bb,
The device side video encoding unit 50A based on the output of the control unit 6
Since the output switching unit 22 provided for each time division multiplexer 2 for switching the input to the time division multiplexer 2 from a, 50Ab, 50Ba, 50Bb is provided, a plurality of conferences are held concurrently in parallel. In each case, 1 for each meeting
Even when terminals having different communication capacities are mixed in the terminals forming one video conference, the respective video conferences can be held.

According to the present invention, multiplexed terminal information is input from a plurality of video terminals to separate the terminal video data from the terminal information, and the coded composite video data described later and other data are multiplexed. A plurality of time division demultiplexing units for sending to the video terminal, a plurality of video decoding units for decoding the terminal video data from the plurality of video terminals, and a control command output based on the control data included in the terminal information. A control unit, a video creation unit that combines decoded data decoded by a plurality of video decoding units based on a control command to generate composite video data, and a plurality of encoded composite video data generated by encoding the composite video data. Since the number of video encoders is less than the number of time-division demultiplexers to be output to the time-division demultiplexer, the video composed of analog signals for a certain multipoint communication is provided. The video encoding unit for encoding is the need is eliminated to provide for each video terminal, it is possible to obtain a communication control device between an inexpensive multipoint.

Since the video encoding unit is provided according to the type of communication capacity to be performed with the video terminal, terminals having different communication capacities are mixed in the terminals forming multipoint communication. Even in the case, multipoint communication can be performed.

Further, since the video encoding unit is provided according to the number of multipoint communication which are simultaneously performed in parallel between different video terminal groups of the plurality of video terminals, the parallel simultaneous transmission of a plurality of multipoint communication is performed. It is possible to reduce the processing load of the video encoding unit when the event is held.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a multipoint communication control apparatus according to a first embodiment.

FIG. 2 is a configuration diagram of a multipoint-to-point communication control apparatus according to the second embodiment.

FIG. 3 is a configuration diagram of a multipoint communication control apparatus according to a third embodiment.

FIG. 4 is a configuration diagram of a multipoint-to-point communication control device according to a fourth embodiment.

FIG. 5 is a configuration diagram of a conventional multipoint communication control device.

FIG. 6 is a configuration diagram of a conventional multipoint communication control device.

FIG. 7 is a diagram showing an example of output display on an output display unit 19 of a terminal 10 in a conventional video conference.

[Explanation of symbols]

 21 input switching section, 22 output switching section.

Claims (3)

[Claims] 1. Inputting multiplexed terminal information from a plurality of video terminals to separate the terminal video data from the terminal information, and at the same time, by multiplexing coded composite video data described later and other data, the video A plurality of time division demultiplexing units for sending to the terminal, a plurality of video decoding units for respectively decoding the terminal video data from the plurality of video terminals, and outputting a control command based on the control data included in the terminal information. A control unit, a video creation unit that synthesizes the decoded data decoded by the plurality of video decoding units based on the control command to generate synthetic video data, and the coded synthesis that is generated by encoding the synthetic video data. A multipoint-to-point communication control apparatus comprising: a plurality of time-division demultiplexing units that output video data to a plurality of time-division demultiplexing units. 2. The multipoint communication control device according to claim 1, wherein the video encoding unit is provided according to the type of communication capacity to be performed with the video terminal. 3. The video encoding unit according to claim 1, wherein the video encoding unit is provided in accordance with the number of multipoint communication simultaneously performed in parallel between different video terminal groups of a plurality of video terminals. Multipoint communication control device.