KR0166258B1 - Video mixer and video conference system using the same - Google Patents

Abstract

The present invention relates to a video mixer and a video conferencing system using the same, comprising: a plurality of decoders 11-1 to 11-4 for decoding video data received by a plurality of video cameras; A plurality of low pass filters 12-1 through 12-4 for low-pass filtering the outputs of the decoders 11-1 through 11-4, respectively; a plurality of condensers 13- down sampling the low-pass image data; 1-13-4); An image assembler 14 for receiving the outputs of the compactors 13-1 to 13-4 and assembling them into one image; And an encoder 15 that encodes the image assembled by the image assembler 14, so that the meeting can be performed while watching a meeting participant who is divided and distorted on the monitor, thereby reducing the number of monitors required. In addition, it is effective to see the appearance of the meeting attendees at the same time.

Description

Video Mixer and Video Conferencing System

1 is a block diagram showing a conventional video conferencing system.

2 is a block diagram showing a video conferencing system to which the present invention is applied.

3 is an exemplary view of a screen displayed in the terminal according to the present invention.

4 is a block diagram illustrating a video mixer according to the present invention.

* Explanation of symbols for main parts of the drawings

10: video mixer 11-1 to 4: decoder

12-1 ~ 4: Low pass filter 13-1 ~ 4: Reducer

14: Image Assembly Machine 15: Encoder

T1-T4: Video Conference Terminal V1-V4: Video Camera

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a videoconferencing system, and more particularly, to a video mixer for receiving a video signal from a plurality of videoconferencing terminals (hereinafter, referred to as a terminal), and then mixing and outputting them as a single output. It is about.

With the development of the communication system, the compression technology of digital video data has been developed, and the video conferencing system has appeared to allow people at a long distance to have a meeting while watching the image displayed on the monitor screen.

FIG. 1 is a schematic diagram showing a conventional video conferencing system composed of four terminals, each of which includes terminals T1 to T4 interconnected by a transmission channel capable of transmitting video data at high speed, and each terminal T1 to T1. T4) is attached to the video camera (V1 ~ V4) that converts the appearance of the person who attended the video conference to the electrical signal.

That is, in the conventional video conferencing system, a video camera (V1 ~ V4) is captured by a video camera (V1 ~ V4), converted into an electrical signal, encoded, and transmitted to the other party through a transmission channel. The video signal was received, decoded, and output to the monitors of the terminals T1 to T4.

For example, in a high-tech building equipped with a video conferencing system, Terminal 1 (T1) and Video Camera 1 (V1) are installed in the Planning Manager's Office on the second floor, and Terminal 2 (T2) and Video Camera 2 (V2) are located on the sales floor on the fifth floor. When the terminal 4 (T4) and the video camera 4 (T4) is installed in the director's office on the seventh floor, the video captured by the video camera 1 is transmitted to the respective terminals 2, 3, and 4 through the transmission channel. In addition, the video data captured by the video camera 2, the video camera 3, and the video camera 4 are received and displayed on the monitor.

In this case, images input from three video cameras may be simultaneously displayed on three monitors, or one of the three images may be selected and displayed on one monitor.

Therefore, since three monitors were required to simultaneously display three images, the number of monitors increased, and when only one image was selected and displayed, there was a problem in that other conference attendees were not seen.

In addition, when the four terminals as described above requires at least three channel capacities for data transmission, the transmission bandwidth of the transmission path should be wide or multiple transmission paths should be installed.

Accordingly, the present invention has been made to solve the above problems, by concentrating the video data to be transmitted and reducing the amount of transmission data by condensing each, and then mixing and outputting on one transmission channel to efficiently use the transmission channel. In addition, it is an object of the present invention to provide a video mixer of a video conferencing system to reduce the monitor required by displaying each conference counterpart on a single screen.

In order to achieve the above object, the apparatus of the present invention is a video conferencing system in which video data input from a plurality of video cameras is reduced, mixed, compressed and transmitted on each terminal, and each decoding of the video data. A plurality of decoders; A plurality of low pass filters for low pass filtering the outputs of the decoder, respectively; A plurality of condensers for down sampling the low pass image data; An image assembler that receives the output of the condenser and assembles it into one image; And an encoder for encoding the image assembled by the image assembler.

That is, the present invention pairs with a video conferencing terminal and receives the video of the attendees captured by the video cameras installed in the far distance, decodes, low-passes, and performs the shortening, and then edits the shortened video into one screen. It is to display all the meeting parties on one monitor.

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention.

The video conferencing system to which the present invention is applied includes a video camera (V1 to V4) which is installed together at a position of a terminal as shown in FIG. A video mixer (10) for decoding, low-pass filtering, and narrowing down image data received from the video cameras (V1 to V4), combining them into one screen, encoding the same, and outputting the same on one transmission path; The first to fourth terminals T1 to T4 receive the combined image from the video mixer 10 and decode the image to be displayed on the screen.

Here, the video camera is installed together at the position of the terminal 1 so that the video camera 1 (V1) and the terminal 2 (T2) and the video camera 1 (V1), which is output together on the transmission path after soaking the image of the meeting participant is installed together Video camera 2 (V2) and terminal 3 (T3) are installed together to capture the video of the video after coding and output it on the transmission path to take the video of the conference attendant after coding and output to the transmission path 3 (V3) and the terminal 4 (T4) is installed together, the video camera 4 (V4) to take the image of the attendees of the conference and then code and output on the transmission path.

At this time, the transmission path from the video cameras V1 to V4 to the video mixer 10 and the transmission path from the video mixer 10 to the terminals T1 to T4 may be installed with cables at a close distance. In case of a long distance, the transmission line may be formed through a local area network or a public network.

In addition, the terminals T1 to T4 are provided with video signal receiving means for ding after receiving the video signal and a monitor for displaying the decoded video. In the drawing of FIG. Although the terminals V1 to V4 and the terminals T1 to T4 are separated from each other, the terminals T1 to T1 and the corresponding video cameras V1 to V4 are usually installed at the same position.

In the video conferencing system as described above, the video camera 1 (V1) and the terminal 1 (T1) are installed at the same position, and output the video of the meeting participant located in front of the video camera 1 (V1) to the video mixer 10, and the video mixer ( 10) After receiving the mixed video signal from the decoded, the video of the conference attendees including themselves is divided and displayed on one screen as shown in FIG. In this case, when the video conferencing system is composed of four video cameras and terminals as in the embodiment of the present onset, the video input to the video mixer 10 is 4 channels, and the video output from the video mixer 10 is 1 channel. The image data should be reduced to at least one quarter so that the four condensed images are combined to form a capacity of one channel.

The video mixer according to the present invention applied to the videoconferencing system as described above includes a plurality of decoders 11-1 to 11- that decode video data received from the plurality of video cameras as shown in FIG. 4) and; A plurality of low pass filters 12-1 through 12-4 for low-pass filtering the outputs of the decoders 11-1 to 11-4; A plurality of condensers 13-1 to 13-4 for down sampling the low-pass image data; An image assembler 14 for receiving the outputs of the compactors 13-1 to 13-4 and assembling them into one image; And an encoder 15 assembled by the image assembler 14 to encode an image.

Next, the effect of this invention comprised as mentioned above is demonstrated.

First, the video mixer 10 according to the present invention can display the appearance of the conference attendees on one monitor by appropriately dividing the monitor screen according to the number of terminals (that is, the number of conference attendees) constituting the video conference system. It is necessary to publish the video data soared by the video camera at an appropriate reduction ratio according to the number of conference attendees. In the embodiment of the present invention, since four terminals are used, as shown in FIG. 3, one screen is divided into four to display the appearance of a meeting participant. Therefore, in the embodiment of the present invention, the extraction rate of the accumulator is 4: 1.

When the video cameras installed with the respective terminals are soared and the encoded image data is input to the video mixer 10 through the transmission channel, the decoders 11-1 to 11-4 decode the image data inputted from the respective channel. After that, the low-pass filters 12-1 to 12-4 are output, and the low-pass image data is reduced at a predetermined reduction rate in the accumulators 13-1 to 13-4. Images shrunk in the condenser 13-1 to 13-4 are assembled into image data of one screen in the image organizer 14, and then compressed and encoded again by the encoder 15 to transmit each terminal (through a transmission path). T1 ~ T4). Therefore, in each terminal (T1 ~ T4), the meeting participant can conduct the meeting while watching the other participant who is divided and displayed on the monitor, which reduces the number of monitors required and can simultaneously view the participant. have.

As described above, the video mixer according to the present invention can efficiently use a transmission channel by shortening the image data input through multiple channels and outputting the same on one transmission channel. In this case, it is possible to proceed with the meeting while watching the appearance of the meeting participant divided on the monitor, thereby reducing the number of monitors required and simultaneously seeing the appearance of the meeting participant.

Claims (2)

A plurality of decoders 11-1 to 11-4 for decoding image data received from a plurality of video cameras, respectively; A plurality of low pass filters 12-1 through 12-4 for low-pass filtering the outputs of the decoders 11-1 through 11-4, respectively; a plurality of condensers 13- down sampling the low-pass image data; 1 to 13-4): An image assembly unit 14 for receiving the outputs of the condenser 13-1 to 13-4 and assembling the images into one image: and encoding the image assembled by the image assembly unit 14. A video mixer composed of an encoder (15). A video camera (V1 to V4) installed together at the location of the terminal to capture an image of a meeting party, and then code and output the video on a transmission path; A video mixer (10) for decoding the image data received from the video cameras (V1 to V4), low-pass filtering, and reducing the data at a predetermined reduction ratio and then adding them together into one screen; And first to fourth terminals (T1 to t4) for receiving the summed image from the video mixer (10) and then decoding and displaying the image on a screen.