Design And Implementation Of Video Conference Controlling System Based On Multitreading

As the advancement of computer, communications, image compressing technologies etc, multimedia technology has been developed rapidly. Video conference system (VCS) is an important branch of multimedia application, which has got more and more attention. It can offer users with direct and general communication, which can save time, reduce cost, improve productivity. It also has been playing an important role in sociality information intercommunication.This paper regards centralized VCS based on Internet as investigated subject. Combining with the research status of the subject, it introduces the two VCS international standard H.323 protocol standard and SIP protocol standard, and also compares with each other. The thesis also makes research on the keystone technology of transmitting of stream media,coding and decoding of audio/video frequency,NAT traveling etc, and makes some improving.Through reading a great deal of domestic and overseas documents and referring to general architecture of video conference system, this paper proposes a centralized VCS based on multithreading, and gives the system structure and logistic function structure. The paper also designs and implements the conference controlling system concretely, introduces the work elements,function module and implementation method.VcomOffice system is composed of client and server, and the server is also divided into conference controlling server (CCS) and stream media transmitting sever (SMTS). CCS is the administrator of conference flow and the executor of system inner affair. SMTS is used to control and transmit audio/video data. The system adopts Socket programming technology in Linux, multithreading buffer pool to receive and transmitting. The paper also gives conference flow and its implementation means of the system which can realize the general video conference function, and it can become a powerful applied video conference system, with its extending.At last, the thesis summarizes the research results of the subject, and makes a prospect of the next task aim and research direction.