Improvements Of Online Multimedia Conferencing System Based On Html5

With the development of internet, people increasingly complete their work through the internet, such as E-mail, search engine, JingDong shopping on-line, Qvna net and so on. Network communication has huge advantage, because its high transmitting speed reduces consumption of manpower, material and time. Multimedia Conferencing System (MCONF) makes the realistic conference holding on the internet, which makes organizing a meeting in different places easier. When the HTML5technology is put forward, some of its technology can be used to improve the functionality and performance of MCONF.The main work of this thesis is to improve the chat room module of the multimedia conferencing systems. This work is based on the WebSocket in HTML5. The WebSocket protocol is an upgrade edition of the HTTP1.1. The HTTP protocol is a stateless connection and the WebSocket connection is the opposite. The communication mechanism of WebSocket protocol is a state of full-duplex connection-oriented way. The HTTP head information will be sent by the WebSocket only in the initial request stage. When it is in a communication state, directly within the channel of the server and the browser will send and receive real-time messages, which had improved chat performance and user experience. With WebSocket communication mode, the chat message in the chat room module improves instant message communication upgraded to real-time message communication. In the new communication logic, a WebSocket communication channel open at the same time as the framework which is embeded in the browser page open. This channel connects the browser and the server and it is a full-duplex communication channel. In the browser side, establish a WebSocket communication channels must be new the WebSocket object of the DOM to create a new instance of the object on the page to manage the browser side of the channel. On the server side, use a Servlet inherited WebSocket Servlet class in Tomcat to manage server-side channel. The server side of all channels managed by the special Servlet. In this communication mode, all channels are used confld and user to uniquely identify. Fetching messages is no longer using AJAX or long polling. You receive a message while the message is sent to you. The messages storage is used the thread. The messages are stored in a message pool. When the thread stores the message from the message pool, the message can remove from the memory.This thesis also provides a new method for the achievement of video communication module. That is to say, the JMF framework and Applet embedded element technology can be displaced by video, canvas and WebSocket technology to achieve the video communication function. There into, information flow of the video can be transmitted to the video element controlled by the JavaScript for data source. The picture of the video can be captured and stored in Canvas. And then the data in the canvas can be sent to the remote canvas through WebSocket. Because of the fixed-hour work of the canvas, there will be no difference between the video information with picture and the video information with JMF when the timer is set reasonable.Finally, this thesis optimizes front end function of the original MCONF. According to the famous fourteen rules of the Yahoo engineer for front end performance optimization, it optimizes the CSS and JavaScript in the front end code of the MCONF.