JP2644031B2 - Multipoint image composition method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Overview] Regarding a method of synthesizing a multi-point image in a video conference system, reduced screen data is transmitted together with normal screen data, and the reduced image extracted when each image of the conference room is synthesized on one screen. The purpose of this is to create a screen based on screen data and to simplify hardware and prevent image quality degradation. A transmission device that shoots a meeting pattern and transmits the image data, and monitors the received pattern of each meeting Multi-point master device that creates composite screen data based on image data sent from each conference room and distributes the composite screen data to each conference room And a communication line connecting each conference room with the multipoint master device, a normal screen data of a normal size and a reduced screen data of a reduced screen are provided in each conference room. And a transmitting device for transmitting image data to the multi-point master device. The multi-point master device obtains reduced screen data from the image data of the normal screen data and the reduced screen data of the reduced screen transmitted from each transmitting device. And a synthesizing device for creating one screen of synthetic screen data after adding display area information based on the reduced screen data extracted by the screen data extracting apparatus. It is configured to simplify the conference system.

[Industrial applications]

The present invention relates to a method for synthesizing a multipoint image in a video conference system.

2. Description of the Related Art As the use of videoconferencing has increased, it has been required to efficiently combine images of each conference room on one screen.

[Conventional technology]

A teleconference system in which a plurality of conference rooms are connected by a communication line and a conference is held between remote locations is provided in each conference room 1-1, 1-2,..., 1-N as shown in FIG. A camera 9, a codec 10 and a monitor 11 were provided, and the screen data of a meeting pattern captured by the television camera 9 was subjected to data compression encoding by the codec 10 and transmitted to the multipoint master device 2 via the communication line 3. . The multipoint master device 2 combines the image data sent from each of the conference rooms 1-1, 1-2,..., 1-N into one screen of screen data, and transmits the combined screen data to the communication line 3. Each meeting room 1-1, 1-2, ..., 1-N
To each conference room 1 in the form divided into monitors 11
.., 1-N are displayed.

The conventional multipoint master device 2 employs a configuration as shown in FIG. That is, each conference room 1-1, 1-
The image data sent from each of the conference rooms 1-1, 1-2,..., 1-N is received by a reception line control unit 12 provided for 2, N,. The image data that has been compression-encoded in 13 is decoded into original screen data. The screen data decoded by each decoding unit 13 is output to the pixel thinning unit 14.
For example, when a video conference is performed between four conference rooms, the screen data is thinned out every other one, and the thinned four screen data is combined to form one screen composite screen data. Screen data is stored in the video memory 15. The combined screen data of one screen stored in the video memory 15 is encoded by the encoding unit 16 and further transmitted to each of the conference rooms 1-1, 1-1 via the selection unit 17 and the transmission line control unit 18.
-2, ..., 1-N.

The selection unit 17 determines whether a plurality of composite images taken in each of the conference rooms 1-1, 1-2,..., 1-N are images of the other party's conference room as in a one-on-one conference. In the case of a single video selection, the receiving line control unit 12 corresponding to the other party's conference room directly transmits the selection of the other party's conference room via the selection unit 17 and the transmission line control unit 18. Image data is sent.

[Problems to be solved by the invention]

, 1-N of the conventional conference rooms 1-1, 1-2,..., 1-N are thinned out by the multipoint master device 2, and one screen of screen data is synthesized. -2, ..., 1-N, the encoding unit 16 and the decoding unit corresponding to each conference room
However, there is a disadvantage that the amount of hardware is increased due to the necessity of 13.

Also, with respect to image data, since the encoding / decoding is performed on the conference room side and the multipoint master device 2 side, respectively, and is performed twice, there is a disadvantage that the image quality deteriorates.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks by transmitting reduced screen data together with normal screen data, and creating the reduced screen data based on the extracted reduced screen data when combining the images of the conference room into one screen. It is intended to simplify hardware and prevent deterioration of image quality.

[Means for solving the problem]

In order to combine each image of the above conference room into one screen, if the screen data of each conference room can be thinned out before decoding, the amount of hardware can be reduced, but there is a limitation in the encoding algorithm. Scalar quantization, which performs quantization in pixel units, can be performed. However, in recent technology, a block-based processing method in which several pixels are processed collectively for low transmission speeds is common. Therefore, it is extremely difficult to thin out the screen data before decoding.

Therefore, in the present invention, two-screen image data including normal screen data and reduced screen data are transmitted from each conference room to the multipoint master device, and when the images of the conference room are combined into one screen, the reduced screen data is used. Was created.

 FIG. 1 is a basic configuration diagram of the present invention.

1-1, 1-2,..., 1-N are conference rooms where conferences are held while viewing images in other conference rooms, and 2 is a multipoint master device, each of which is being conferenced. Receiving two screen image data of normal screen data and reduced screen data from the conference room, and creating a single screen composite screen data based on the reduced screen data for a conference involving three or more points. What transmits the synthesized screen data to each conference room being performed, 3 is a communication line and image data is transmitted digitally, 4 is a transmission device, which displays a conference pattern of the conference room photographed. As shown in FIG. 2, which will be described later, two screen image data of normal screen data and reduced screen data in which pixels are thinned out are transmitted to the multipoint master device 2, and 5 is a receiving device, which is a multipoint master device. The synthesized screen data sent from the master device 2 and the other party in the one-to-one conference A screen data extracting device which receives the normal screen data of the above-mentioned, and reproduces the conference pattern in a divided form or a normal single screen on the monitor 11; 7 for extracting reduced screen data from image data of two screens, i.e., reduced image data and reduced screen data. Reference numeral 7 denotes a synthesizing device, which is transmitted from the screen data extracting device 6 based on selection information of a conference room where a conference is being held. The one that receives reduced screen data, and adds display area information indicating where the reduced screen data is to be displayed on the monitor 11 of the receiving device 5 to create composite screen data of one screen. Reference numeral 8 denotes a line control device, and each conference room 1
.., 1-N and image data sent to each conference room 1-1, 1-2,..., 1-N.

[Action]

Now, for example, # 1 meeting room 1-1 to # 4 meeting room 1-4
Assuming that a conference is being held at the four points described above, the transmission devices 4 in the # 1 conference room 1-1 through the # 4 conference room 1-4 receive the # 1 conference with the timing shifted as shown in FIG. Image data of two screens of reduced screen data and # 1 normal screen data are transmitted to the multipoint master device 2 via the communication line 3 respectively. The # 1 to # 4 reduced screen data can be obtained by thinning one pixel at a time from normal screen data by each thinning circuit or the like.

Out of the image data of each of the two screens sent to the multipoint master device 2, # 1 and # 4 reduced screen data are extracted by the correspondingly provided image data extraction devices 6,
Since the extracted # 1 to # 4 reduced screen data are already shifted in timing at the time of transmission, the second
As shown in the drawing, the area information to be displayed is added to each of them, and the area information is created by the synthesizing device 7 as one screen of synthesized screen data. The combined screen data is sent to the # 1 conference room 1-1 to the # 4 conference room 1-4 via the line control device 8, respectively, received by each receiving device 5, and placed at a predetermined designated position in the # 1 conference room. The conference pattern of the rooms 1-1 to # 4 conference room 1-4 is projected on the screen of the monitor 11 in a divided form.

At the time of the two-point conference, the image data sent in the line control device 8 is sent back to the other party's conference room, and the reception device 5 reproduces the conference pattern on one screen.

〔Example〕

FIG. 3 shows an embodiment of a multipoint image synthesizing method according to the present invention, wherein reference numerals 2 and 6 correspond to those in FIG. 1, and 12, 17, and 18 correspond to those in FIG. Correspondingly, reference numeral 19 indicates a combination selection unit, 20 indicates a selection control unit, and 21 indicates a display area information addition unit.

From each of the conference rooms 1-1, 1-2,..., 1-N to the multipoint master device 2, the normal screen data of the normal size, the reduced screen data of the combined reduced size, and the image data of the two screens are transmitted to the conference. In a mode in which the timing is shifted between the rooms, for example, as described in FIG. 1 above, an example in which conferences are held at four points from the # 1 conference room 1-1 to the # 4 conference room 1-4 will be described. It is accepted by the receiving line control unit 12 provided correspondingly with the timing shift shown in FIG. The image data of two screens received by each receiving line control unit 12 is input to the respective screen data extracting device 6, and only the reduced screen data is extracted by the screen data extracting device 6, respectively. That is, # 1 reduced screen data is extracted from the image data transmitted from the # 1 conference room 1-1, and # 2 reduced screen data is extracted from the image data transmitted from the # 2 conference room 1-2. The # 3 reduced screen data is extracted from the image data transmitted from the third conference room 1-3, and the # 4 reduced screen data is extracted.
# 4 reduced screen data is extracted from the image transmitted from the conference room 1-4. When these # 1 reduced screen data to # 4 reduced screen data are input to the synthesizing selection unit 19, they already have a timing deviation, and the # 1 conference rooms 1-1 to # 4 from the selection control unit 20 Indicates these # 1 reduced screen data or # in response to a control signal designating the conference room 1-4.
Based on the 4 reduced screen data, the combined selection unit 19 creates one combined screen data, and the display area information adding unit 21 determines the display area information on which position on the display screen to display. It is added by the instruction, and the combined screen data shown in FIG. 2 is created.

The composite screen data is distributed to each conference room,
From the display area information of the composite screen data, # 1 conference room 1-1
The selection unit 17 provided corresponding to the conference rooms # 1 to # 4 selects the passage of the composite screen data, and the transmission line control units 18 control the transmission lines # 1 to # 4. 1-
The synthesized screen data is transmitted to the respective sections.

Accordingly, the combined screen data is received in the # 1 meeting rooms 1-1 to # 4 meeting rooms 1-4 and displayed on the monitor 11 to be divided into four # 1 meeting rooms 1-1 to # 4 meeting rooms 1--1.
4 conference patterns are displayed at predetermined positions on one screen.

In the above explanation, explanations were given for four conference rooms.
It is needless to say that the conference pattern of each conference room is displayed in a divided form on one screen as in the above-mentioned case also in the case of the above multipoint.

In the case of a point-to-point conference, the image data received by the receiving line control unit 12 is selected by a selecting unit 17 provided corresponding to the other party's conference room. It is transmitted to each other's conference room through the unit 18.

[Effects of the Invention] As described above, according to the present invention, the normal screen data and the reduced screen data are transmitted to the multipoint master device after the timing is shifted for each conference room. Then, only reduced screen data is extracted and one screen of composite screen data is created, so decoding and encoding by the multipoint master device are required, and the reduced screen data is extracted as compared with the decoding and encoding. The screen data requires a very small amount of hardware such as an extraction device, so that the hardware amount of the entire system can be reduced.

Since the encoding and decoding can be performed only once, deterioration of the image quality can be prevented.

[Brief description of the drawings]

FIG. 1 is a diagram showing the basic configuration of the present invention, FIG. 2 is an explanatory diagram of the creation of composite screen data, FIG. 3 is an embodiment of a multipoint master device according to the present invention, and FIG. FIG. 5 and FIG. 5 show the configuration of a conventional multipoint master device. In the figure, 1-1, 1-2, ..., 1-N are conference rooms, 2 is a multipoint master device, 3 is a communication line, 4 is a transmitting device, 5 is a receiving device, 6 is a screen data extracting device, 7 Is a synthesizer, 8 is a line controller, 9 is a camera, 1
0 is a codec, 11 is a monitor, 12 is a line controller for reception, 13
Is a decoding section, 14 is a pixel thinning section, 15 is a video memory, 16
Denotes an encoding unit, 17 denotes a selection unit, 18 denotes a transmission line control unit, 19 denotes a combination selection unit, 20 denotes a selection control unit, and 21 denotes a display area information addition unit.

Claims (1)

(57) [Claims] A plurality of conference rooms (1) each having a transmitting device (4) for photographing a pattern of a conference and transmitting the image data of the conference, and a receiving device (5) for monitoring the received pattern of each conference. −
1, 1-2,..., 1-N) and image data sent from each conference room (1-1, 1-2,. A multipoint master device (2) for distributing the synthesized screen data to each conference room (1-1, 1-2,..., 1-N); and a multipoint master device (1-1, 1-2,. -N) and a communication line (3) connecting the multipoint master device (2) to a conference room (1-1, 1-2, ..., 1-N). A transmission device (4) for transmitting image data of normal screen data of a normal size and reduced screen data is provided, and transmitted from the transmission devices (4) to the multipoint master device (2). A screen data extraction device (6) for extracting reduced screen data from image data of normal screen data and reduced screen data of a reduced screen, and a screen data extraction device (6). A combination device (7) for creating combined screen data of one screen after adding display area information based on the reduced screen data extracted as described above.