JPH0454089A - Multi-point television conference system - Google Patents

Abstract

PURPOSE:To send a signal while multiplexing lots of picture information for an invalid block of a transmission signal by applying picture element and line thinning processing and compression code processing to picture information of N-sets at maximum respectively into 1/N as a transmitted compressed picture data signal and inputting the result to a picture exchange device where an optional compressed picture data signal is subjected to 1/N demultiplexing on request from each point for picture exchange. CONSTITUTION:A selection circuit 10 selects compressed picture data signals(a), (b), (c), (d) from points A, B, C, D according to a selection instruction on request from, e.g. a point M received from a control input terminal 2. Signals A1, B2, C1, D3 among compressed picture data signals from the points A, B, C, D adjusted to a prescribed phase are multiplexed to be one-frame structure by a time division multiplexer 30 and the result is sent to the point M via an output terminal 3. A television conference terminal equipment 50 at the point M uses a picture code decoder 56 to apply decoding processing to the received multiplexing signal and outputs a television picture signal to a receiver 55.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a multipoint video conference system, and particularly to a compressed image data signal exchange processing system.

[Conventional technology]

Conventionally, in this type of multipoint video conference system, when compressed image data signals from arbitrary multiple points among the conference participating points are combined using an image exchange device and transmitted to each point, one piece of image information is sent to each point. The image is thinned out to 1/N (N is the number of divisions for screen composition) and compressed and encoded, and is transmitted to an image exchange device via a high-speed digital line at a transmission speed of 1/N. A 1/N compressed image data signal received from a point is time-division multiplexed and sent to each point, and each point decodes the received compressed image data signal to create a TV image that is synthesized into N divided screens. The signal was regenerated and displayed on a receiver.

Next, 4-split screen composition will be explained as an example with reference to FIG. 5.6.7. FIG. 5 is a block diagram of the image exchange device, FIG. 6 is a time chart showing the operation of four-screen composition in the image exchange device, and FIG. 7 is a diagram showing the composite image display on the image receiving device.

As shown in a, b, c, and d of FIG. -1.
Input in 1-2.1-3.1-4 respectively. This received compressed image data signal is input to the selection circuit 10. The selection circuit 10 also receives compressed image data signals from points other than points A, B, C, and D that have been similarly thinned out to 1/4 and compressed and encoded. Selection circuit 10
receives a selection instruction from control input terminal 2, and selects points A, B, and C.
, D. The compressed image data signals received from the selected points A, B, C, and D each have a phase difference as shown in a, bc, and d in FIG. 6 because each point is independently synchronized. The selected compressed image data signals a, b, c,
d is phase-adjusted by the phase control circuit 20 as shown in e, f, g, h of FIG. It30
The signals are combined into one frame structure as shown in FIG. This time division multiplexed point A
, B, C, and D are decoded at, for example, point n, and a four-part composite image as shown in FIG. 7, for example, is displayed on the receiver.

[Problem to be solved by the invention]

In the conventional multipoint video conferencing system described above, the transmission speed of the compressed image data signal sent from each point to the image exchange device is 1/N (N is the number of divisions for screen composition). There is a drawback that the transmission speed equivalent to N-1 is wasted compared to the transmission speed of the compressed image data signal that is divided into N and combined and sent to the computer.

An object of the present invention is to perform pixel and line thinning processing, compression encoding processing, and transmitting each of up to N pieces of image information to 1/N for the number N of divisions to be synthesized in a video conference terminal device at each location. An object of the present invention is to provide a multipoint video conference system in which a compressed image data signal is input to an image exchange device, and the image exchange device synthesizes arbitrary compressed image data signals into N parts according to requests from each point and exchanges images. .

[Means to solve the problem]

The multipoint video conference system of the present invention compresses and encodes a plurality of image information, time-division multiplexes it at a predetermined position, transmits it to an image exchange device, combines the plurality of image information, and performs time-division multiplexing. a video conference terminal device that receives the compressed image data signal from the image exchange device and decodes the plurality of compressed image data signals into one composite screen; and inputs the compressed image data signal from the video conference terminal device. In a multipoint video conferencing system comprising an image exchange device that performs screen compositing of a predetermined number of divisions and outputs the divided and composite compressed image data signal to the video conference terminal device, the number N of divisions to be composited is On the other hand, the image exchange device inserts a frame header into each of the compressed image data signals which have been subjected to pixel and line thinning processing to 1/N and compression encoding processing to each of the maximum N pieces of image information, and time-division multiplexing them. a video conference terminal device that decodes the compressed image data received from the image exchange device and displays a divided composite image on the image receiving device; Input the compressed image data signal and move to the specified N point (
a selection means for selecting a compressed image data signal to which a frame header is attached (N is an integer such that n≧N≧1 and allows duplication of the same point), and a compressed image data signal to be outputted by the selection means is respectively specified. A phase control means for adjusting the phase, and a time division multiplexing means for time division multiplexing N compressed image data signals adjusted to a predetermined phase by the phase control means at a predetermined position, each having n points. , and an image exchange device for exchanging compressed image data signals.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of an image exchange device showing one embodiment of the present invention, FIG. 2 is a time chart showing the operation of one embodiment of the present invention, and FIG. 3 is a composite image of one embodiment of the present invention. The display diagram, FIG. 4, is a block diagram showing the system configuration of the multipoint video conference according to the present invention.

FIG. 1 shows a selection circuit 1 that selects compressed image data signals from arbitrary plural points among compressed image data signals received from each point according to a control designation inputted from a control input terminal 2.
0, a phase control circuit 20 that adjusts the phase of the compressed image data signals of each point selected by the selection circuit 10 to generate a divided composite signal of one frame configuration, and a phase control circuit 20 that adjusts the phase of the compressed image data signal of each point selected by the selection circuit 10, and A time division multiplexing device 30 that performs time division multiplexing and input terminals 1-1.1-2.1-3゜1-4...1 for connecting compressed image data signals from each point.
-n, and an output terminal 3 at each point for sending out time-division multiplexed compressed image data signals.

FIG. 4 shows image capturing devices 51, 52, 53, and 54 that capture various information necessary for a video conference, an image receiving device 55 that displays a split screen composite signal of a transmission point, and image information output by each image capturing device. an image encoding/decoding device 56 that performs pixel and line thinning processing and compression encoding processing to 1/4, respectively, and decodes the multiplexed compressed image data signal received from the image exchange device and outputs it to the image receiving device; A teleconference terminal device 50 at point A, which consists of a time division multiplexing device 57 that multiplexes compressed image data signals of image pickup devices 51, 52, 53, 54 that have been thinned out and compressed and encoded, and the same as point A. It is composed of points B, . . . M having a similar configuration, and an image exchange bag 240.

Here, the number of divisions for screen composition is set to 4 divisions (N = 4),
An example will be described in which point M receives image information of points A, B, C, and D (C and D are not shown).

In FIG. 4, the television image signals output from the imaging devices 51, 52, 53, and 54 are decimated to 1/4 and compressed to 1/4, respectively, by an image encoding/decoding device 56. Imaging devices 51 and 52 subjected to compression encoding processing,
The compressed image data signals 53 and 54 are multiplexed in a multiplexing device 57 to form a divided and combined signal of one frame, and sent to the image exchange device 40 via a high-speed digital line 60.
sent to.

The compressed image data signal from point A input to input terminal 1-1 in FIG. 1 is input to selection circuit 10. ---1-
Points A, B, C via n.

It is assumed that similar compressed image data signals are input from points other than D.

The selection circuit 10 selects points A, B, based on a selection instruction inputted from the control input terminal 2, for example, based on a request from point M.
Compressed image data signals a, b, c, and d from C and D are selected (see FIG. 2).

A1 of compressed image data signal a. A2. A3. A4, Bl of b, B2. B3. B4, C1, C2, CB, C of c
4.D of d,,D 2. D, , D4 indicate four compressed image data signals each subjected to pixel and line thinning to 1/4, compression encoding processing, and a frame header inserted into each.

The selected compressed image data signals a, b, c, d are
As shown in the figure, the 0-phase control circuits 20, which have different phases, follow the selection instruction from the M point inputted from the control input terminal 2, and use the frame header to select, for example, A 1
．． B 2, C1, D, are extracted, and Fig. 2 e, f, g,
As shown in h, each phase is adjusted to the designated phase from point M. Points A, B, and C adjusted to a predetermined phase
, D among the compressed image data signals A1. B2. C.I.
, D3 are multiplexed by the time division multiplexer 30 into one frame configuration as shown in 211gj, and sent to the point M via the output terminal 3. The video conference terminal bag [50 at point M converts the received multiplexed signal into an image code and
The decoding device 56 performs decoding processing and outputs the television image signal to the image receiving device 55. The image receiving device 55 includes A1. B2. C,,D.

A 4-part composite image is displayed.

In this way, from among the multiple different image information that each point sends after image and line thinning processing and compression encoding processing,
In accordance with a request from a transmission point, arbitrary image information can be multiplexed into a predetermined number of divisions and composites and then transmitted. Therefore, for example, person A at point A, OH at point B
P calligraphy image B2. The receiving side can freely select the person image C at point C, the image D3 drawn on the electronic blackboard at point D, etc., and hold a meeting.

In this example, four types of image information are divided into 1/2 at each location.
4 was subjected to thinning processing and compression encoding processing, and one image information was extracted from the compressed and encoding processed image information of each point using an image exchange device and combined into 4 parts. It goes without saying that the divisional composition is not particularly limited. [Effects of the Invention] As explained above, the present invention is capable of combining a maximum of N divisions for the number of divisions to be composited in a video conference terminal device at each location. The image information of 1/N is subjected to pixel and line thinning processing and compression encoding processing, and a compressed image data signal ′, which is transmitted with a frame header attached to each, is input to the image exchange device. By combining arbitrary compressed image data signals into N parts according to requests from each point and exchanging images, it is possible to multiplex and transmit a lot of other image information into the invalid section of transmission speed that was previously wasted. This has the effect of providing more information at the same time in a meeting.

Furthermore, by requesting arbitrary image information from any point from each point, it is possible to easily implement an image exchange system for multipoint video conferences over digital lines.

...high-speed digital line.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an image exchange device showing one embodiment of the present invention, FIG. 2 is a time chart showing the operation of one embodiment of the present invention, and FIG. 3 is a composite image of one embodiment of the present invention. 4 is a block diagram showing the system configuration of the multipoint video conference of the present invention, FIG. 5 is a block diagram of the image exchange device, and FIG. 6 is a diagram showing the operation of 4-screen composition in the image exchange device. The time chart shown in FIG. 7 is a diagram showing a composite image display on the image receiving device.

Claims (1)

[Claims] 1. Compressing and encoding a plurality of image information, time-division multiplexing it at a predetermined position, transmitting it to an image exchange device, and combining and time-division multiplexing the plurality of image information. a television conference terminal device that receives an image data signal from the image exchange device and decodes a plurality of the compressed image data signals into one composite screen; In a multipoint video conference system comprising an image exchange device that performs screen synthesis of the number of divisions and outputs the compressed image data signal resulting from the division and composition to the video conference terminal device, the maximum N
A frame header is inserted into each of the compressed image data signals obtained by performing pixel and line thinning processing to 1/N and compression encoding processing on the respective image information, time division multiplexing, and transmission to the image exchange device; , a video conference terminal device that decodes the compressed image data received from the image exchange device and displays a divided composite image on a receiver device. 2. Input the compressed image data signal from n points (n>1, an integer), and add a frame header for the specified N points (N is an integer, n≧N≧1, allowing duplication of the same point). a selection means for selecting a compressed image data signal output by the selection means; a phase control means for adjusting each compressed image data signal outputted by the selection means to a designated phase; 2. The image exchanger according to claim 1, wherein the image exchanger has time division multiplexing means for time division multiplexing the compressed image data signals at predetermined positions for each of n points, and performs an exchange process of the compressed image data signals. Device.