Shulou(Shulou.com)05/31 Report--

Hello everyone, Lin Fei to answer the above questions, visual conference system built, visual conference system many people do not know, now let's take a look at it!

What is a video conference system and what is its function?

For most enterprises, the construction of video conference system is a big investment. Therefore, how to give full play to the advantages of the built system in remote cooperation and multi-party communication to enable enterprises to quickly get the due return on investment is a problem that must be considered in the early planning of the system. Therefore, we need to analyze the planning requirements of enterprise video conference system one by one from the perspective of network and application.

Have good network adaptability.

It is the basis of the network video conference system, which is used to carry video, audio and all kinds of control information exchanged between video conference equipment distributed in different locations. At present, the information infrastructure construction of domestic enterprises is generally weak. Except for some large enterprises with private intranets, the information exchange between branches of small and medium-sized enterprises is mostly based on the Internet, usually using ADSL as the access method.

However, the communication network based on ADSL access and Internet transmission has many limitations, such as low network bandwidth (the nominal value of ADSL uplink rate is usually about 500K ~ 600K, and the actual available uplink bandwidth is about 300K), poor QoS guarantee capability (unable to provide end-to-end bandwidth stability), lack of public network IP address (resulting in NAT traversal problem). Therefore, when deploying the video conference system under such network conditions, the corresponding requirements for video conference equipment must be put forward in the planning stage. Here are some key indicators for reference.

The device must support video and audio coding technologies to ensure sound and image effects at low bandwidth. According to the current standard, audio coding can choose G.729 (bit rate is 8K) and G.722.1 (bit rate is 24K/32K), and video coding can choose H.264 (under the image quality, especially under the 100K~300K bandwidth, it can save 1.5 ~ 2 times the transmission bandwidth than the previous video coding methods).

The equipment must have good network adaptability to ensure the fluency and stability of the meeting. The main technologies to solve this problem are intelligent packet loss recovery, dynamic rate adjustment, automatic re-invitation after disconnection, QoS and so on. Intelligent packet loss recovery ensures the clarity and continuity of the conference when the network is congested through packet loss detection and retransmission mechanism, and dynamic rate adjustment dynamically adjusts the code rate of video conference by detecting packet loss rate, so as to automatically adapt to network performance, ensure the continuity of meetings and reduce transmission delay. Automatic disconnection and reinvitation can automatically reconnect MCU and video conference terminal after network interruption and recovery, without manual operation, including QoS DiffServ, IP priority and so on. By setting the QoS policy of the parameter matching network, the priority transmission of video and audio streams in the congested network environment can be guaranteed.

The device must provide proxy function to achieve transparent traversal of NAT and firewall. Existing multimedia communication protocols, such as H.323, SIP, MGCP and so on. Two-way video and audio communication cannot be achieved through NAT or firewall. To solve this problem, you can set up the proxy function in the system to traverse the NAT and firewall transparently. In order to simplify the network architecture, it is recommended that the proxy function module be built into the video conference system equipment (such as MCU and video conference terminal).

Support rich features

According to the characteristics of enterprises, the main applications of remote communication using video conferencing system are teleconferencing (including peer-to-peer and multi-party meetings), remote training, remote recruitment, remote trade and cooperation, and so on. Combined with these applications, the system should be able to ensure the actual effect through rich functional features. After practice, the following functions will play a good auxiliary role in video conferencing applications.

Media processing function. Including digital multi-picture and digital intelligent audio mixing. By using the multi-screen function, the moving images of multiple remote meeting locations can be displayed at the same time on a terminal display device, thus enhancing the experience of the meeting site. Through the use of intelligent audio mixing function, we can realize the discussion of multiple speakers at the same time. Besides, before the roll call, I

Dual video streaming function. With the support of the dual video stream function, the demonstration materials such as dynamic images, PPT and data reports of the venue can be transmitted at the same time in the remote conference, which enhances the visualization and practical effect of the application. This function is widely used for reporting meetings and distance training.

Data conferencing function. Through the standard T.120 data conference function, enterprises can use video conference system to achieve collaborative work, such as electronic whiteboard, application sharing, file transfer, text exchange and so on.

At the end of this article, I hope it will be helpful to you.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.