JPH0730875A - Video conference system between many locations - Google Patents

Abstract

PURPOSE:To provide a video conference system between many locations with simple structure in which interleaving processing is executed at a terminal equipment side and picture synthesis processing is executed without converting a digital signal in the video conference controller. CONSTITUTION:The system is made up of coders 100-1 to 100-n revising a transmission picture into a QCIF with a control signal from a video conference controller 200 and the video conference controller 200. The video conference controller 200 is made up of a selection circuit 20 selecting optionally picture data at four spots from n-spots, decoding circuits 30-1 to 30-4 decoding picture data at 4-spot, a pattern synthesis circuit 40 synthesizing the picture data from the 4-spot onto a 1/4 division screen, a coding circuit 50 making high efficiency coding again and a distribution circuit 60 distributing the signal to n-spot.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multipoint video conference system using compressed images, and more particularly to a multipoint video conference system using screen synthesis.

[0002]

2. Description of the Related Art Conventionally, P × 64 CCITT standardized COD
In the multipoint video conference system configured by using EC on the terminal side, P × 64 CCITT standardized COD
QCIF (Quarter Com) encoded by EC
The encoded data is transmitted to the multipoint video conference control device via a transmission line, and the D / A in the multipoint video conference control device is transmitted.
It is converted to an analog signal by the converter, subjected to thinning processing at the analog level, and then each of the analog image signals at each point subjected to the thinning processing is screen-synthesized,
The screen-synthesized signal is converted into a digital signal by an A / D converter and further multiplexed with a separately processed audio signal or the like.

[0003]

Conventional P × 64 CCI
In a multipoint video conference system that is configured by using TT standardized CODEC on the terminal side, thinning processing of image data at each point is performed in the multipoint video conference control device, and further, the multipoint video conference is performed. In the conference controller,
The image data subjected to the thinning-out process is image-synthesized at an analog level. Therefore, since the thinning-out process and the image synthesizing process are performed at the analog level, the circuit used for the process is complicated and the cost becomes high.

The present invention solves the above-mentioned problems, performs thinning-out processing on the terminal side, and multipoint-to-multipoint with a simple structure capable of performing image combining processing as a digital signal in a multipoint-to-multipoint video conference control device. The purpose is to provide a video conference system.

[0005]

According to the present invention, n pieces of transmission data composed of image data and audio data transmitted from different n points are received, and the format of the transmission image among the transmission data is received. To QCIF to encode the signals of the n transmission images decimated to 1/4, and to output n QCIF encoded data, n P × 64 CCITT standardized CODECs, and a transmission line. A multipoint videoconference control device connected to the CODEC via the CODEC, the multipoint videoconference control device receiving the n QCIF encoded data via the transmission path, Separation means for separating the audio data from the QCIF encoded data and transmitting n QCIF image data, and QCIF image data at any four points of the n QCIF image data. Selection circuit for selecting and transmitting the data, four decoding circuits for respectively decoding the QCIF image data of the selected four points and transmitting the QCIF image decoded data, and the four QCIF image decoded data Screen synthesis circuit for synthesizing the four divided screens into one QCIF synthetic image data and transmitting the QCIF synthetic image data, an encoding circuit for encoding the QCIF synthetic image data by CIF and transmitting the CIF image encoded data, and the CIF. A distribution circuit for distributing the image coded data to n points respectively, and audio data at four points selected by the selection circuit among the n audio data separated by the separation means and processed separately. And a multi-point video conferencing system that multiplexes the CIF image coded data and sends the multiplexed data to the transmission path. The stem is obtained.

Further, according to the present invention, the separating means is formed of n line interfaces and n separating circuits, and the multiplexing means is composed of n line interfaces and n multiplexing circuits. A multipoint video conference system characterized by being formed is obtained.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A multipoint video conference system according to the present invention will be described with reference to FIGS. FIG. 1 (a) is a diagram showing an embodiment of a multipoint video conference system according to the present invention, and FIG. 1 (b) is a multipoint video conference used in the multipoint video conference system according to the present invention. It is a block diagram which shows the structure of a conference control apparatus. FIG. 2 is a diagram for explaining the operation of this embodiment.

In FIG. 1A, 1-1, 1-2,
..., 1-n are input / output image signals at n points, and 100-
1, 100-2, ..., 100-n change the transmission image format to QCIF according to an instruction from the multipoint video conference control apparatus 200, and input image signal 1-
It is a P × 64 CCITT standardized CODEC that performs thinning processing of 1, 1-2, ..., 1-n, and further performs high efficiency coding. On the other hand, P × 64 CCITT standardized CODEC
CI transmitted from the multipoint video conference control device 200
When the F encoded data 2-1R, 2-2R, ..., 2-nR is received via the transmission path, the multiplexed CIF encoded data 2-1R, 2-2R ,. And outputs the output image signals 1-1, 1-2, ..., 1-n.

Reference numeral 200 denotes an encoding device 100- for n points.
1, 100-2, ..., 100-n receive QCIF encoded data 2-1S, 2-2S ,. C
IF (Common Intermediate Fo)
rmat) encoded data 2-1R, 2-2R, ..., 2-
It is a multipoint video conference control device that distributes nR.
The encoded data 2-1S / R, 2-2S / R, ..., 2
-NS / R includes both audio data and image data.

In FIG. 1B, 2-1S, 2-2
S, ..., 2-nS are QCIF encoded data transmitted from the n point to the multipoint video conference control apparatus 200 via the transmission path. 10-1, 10-2, ..., 10-n are
The received QCIF encoded data 2-1S, 2-2S,
, 2-nS are a line interface and a separation circuit for separating the audio data and the image data, respectively. Two
0 is a separation circuit 10-1, 10-2, ..., 10 for n points.
Receive QCIF image data of n points separated by -n,
It is a selection circuit for selecting any four points from the QCIF image data of the n points. 30-1, 30-2, 30-
3, 30-4 are QCI encoded by QCIF at 4 points
By decoding the F image data respectively, the QCIF image decoded data 3-1, 3-2, 3-3 of the 1/4 screen are obtained.
3 is a decoding circuit for obtaining 3-4. 40 is a quarter of the four points
QCIF image decoding data 3-1, 3-2, 3-3
3 is a screen compositing circuit that obtains QCIF composite image data 4 by compositing 4 screens 3-4. 50 is a QCI composed of four screens
Highly efficient encoding of the F composite image data 4 by CIF,
It is an encoding circuit for obtaining CIF image encoded data 5. 6
Reference numeral 0 is a distribution circuit that distributes the CIF image coded data 5 which is composed of four screens and coded by CIF to n points. 70
-1, 70-2, ..., 70-n are separation circuits 10-1, 1
0-2, ..., 10-n and separately processed audio data and the like, and CIF image coded data 5 synthesized by four screens and coded are multiplexed to obtain CIF coded data 2-1R, 2
A line interface and a multiplexing circuit for outputting -2R, ..., 2-nR to the transmission path.

Next, the operation of the multipoint video conference system according to the present invention will be described. As shown in FIG. 2A, n
The input images 1-1 to 1-n at the points show image signals of one-half screen. Next, the encoding device 10 at the n point
The transmission image format is changed to QCIF by -1, 10-2, ..., 10-n. Input image signal 1-1,
, 1-2, ..., 1-n are subjected to thinning processing, and are further encoded to be QCIF encoded data 2-1S to 2-2.
FIG. 2B shows the data of one screen converted to −nS and encoded by this QCIF. Next, the QCIF encoded data 2-1S to 2-nS is input to the n input sections of the multipoint video conference control device 200, and image data for any four points is selected from among them. Next, the four decoding circuits 30-1, 30-2, 30-3, and 30-4 decode the selected four QCIF image data, and Q
The CIF image decoded data 3-1 to 3-4 are obtained. Figure 2
(C) is Q obtained by decoding the QCIF image data.
3 shows CIF image decoded data 3-1 to 3-4.
Next, the QCIF image decoded data 3 of 1/4 of 4 points
Each of -1 to 3-4 is screen-combined by the screen compositing circuit 40 into image data for one screen divided into four. As a result, QCIF composite image data 4 in which four screens are combined is obtained as shown in FIG. Next, the QCIF composite image data 4 is subjected to high efficiency encoding by CIF by the encoding circuit 50, and as a result, CIF image encoded data 5 is obtained as shown in FIG. Next, in the distribution circuit 60, the CI
The F image coded data 5 is distributed to n points, and the n CIF image coded data 5 distributed to the n points are line interface and multiplexing circuits 70-1, 70-2 ,.
2 is multiplexed with voice data separately processed by 0-n.
CIF encoded data 2-1R to
It is sent to the transmission line as 2-nR. Next, FIG. 2 (g)
, The output images 1-1 to 1-n output to the terminal at the n point are P × 64 CCITT standardized C
It is an output image which is screen-combined into four parts which are respectively decoded by ODEC10-1, 10-2, ..., 10-n.

[0012]

According to the present invention, the thinning processing is performed in advance on the terminal side and the image synthesis processing is performed as it is as a digital signal in the multipoint video conference control device, so that the circuit used for the image synthesis processing is simplified. The cost can be reduced, and as a result, the structure of the multipoint video conference system can be simplified.

Further, since the image synthesizing process is performed with the digital signal as it is, various adjustments in the image synthesizing process are almost unnecessary as compared with the image synthesizing process at the analog level.

[Brief description of drawings]

FIG. 1 (a) is a diagram showing an embodiment of a multipoint video conference system according to the present invention, and FIG. 1 (b) is a multipoint video conference system according to the present invention. It is a block diagram which shows the structure of a point-to-point video conference control apparatus.

FIG. 2 is a diagram illustrating the operation of an embodiment of a multipoint video conference system according to the present invention.

[Explanation of symbols]

 20 selection circuit 40 screen composition circuit 50 encoding circuit 60 distribution circuit 200 multipoint video conference control device

Claims (2)

[Claims] 1. Received n pieces of transmission data composed of image data and audio data transmitted from different n points respectively, and of the transmission data, the format of the transmission image is changed to QCIF to be 1/4. The n P × 64 CCITT standardized COs for encoding the signals of the n transmission images thinned out to the nth and transmitting n QCIF encoded data
DEC and a multipoint video conference control device connected to the CODEC via a transmission line, the multipoint video conference control device including the n QCIF encoding devices via the transmission line. Separation means for receiving the data, separating the audio data from the QCIF encoded data, and transmitting n QCIF image data, and selecting QCIF image data at any four points from the n QCIF image data Selection circuit for transmitting the data and the QCIF of the selected four points
Four decoding circuits for respectively decoding the image data and transmitting the QCIF image decoded data, and the four QCIs.
The F image decoded data is combined into a 4-split screen, and one Q
A screen synthesizing circuit for transmitting as CIF synthesized image data,
The QCIF composite image data is encoded by CIF, and CI
An encoding circuit for transmitting F image encoded data;
A distribution circuit for distributing the F image coded data to n points respectively, and 4 selected by the selection circuit from the n audio data separated by the separation means and processed separately.
An inter-multipoint video conference system comprising audio data at a point and multiplexing means for multiplexing the CIF image coded data and transmitting the multiplexed data to the transmission path. 2. The multipoint video conference system according to claim 1, wherein said demultiplexing means is composed of n line interfaces and n demultiplexing circuits, and said multiplexing means is n line interfaces and n line interfaces. A multipoint video conferencing system characterized by being formed by individual multiplexing circuits.