Virtual Instruments Online Experiments And Network Video Surveillance Technology

With the development of multimedia and network technology, especially its use in the net-eduation, e-learning has become a new direction in the higher education reform. Multimedia network teaching uses a wide range of advanced technological means. Video technology and Internet-based information technology, as the most frequent used techologies, especially internet-based asynchronous teaching, allows the students' self-study to be the same as the traditional teaching. Because of the network advantages of various aspects in teaching, in recent years, multimedia network teaching develops rapidly. Its scale is becoming larger and larger, with more and more subjects and advanced technological means involved in.According to this line of thought, the paper attempted to develop a web-based virtual instrument system, designed the programs and published them through the B/S model to the internet, so that a variety of virtual instrument experiments can be done through network. This can allow remote students to browse the instrument pannel at the same time carrying out real-time operation. Students would control the server-side equipment through the client control panel.In order to achieve the goal of "seeing believes" in net-experiments, a simple and easy video surveillance system was developed. A web camera was placed at the server-side, which could photograph the real time vedio and send it to the client through internet, so that the client can monitor the user host terminal equipment. To achieve this monitoring function, the technical route was to use VFW (Video for Windows) for server-side video capturing, and then do the digital image processing and video compression. Server and the clients'data communications were through the socket programming and TCP/IP protocol. Clients received video data and coded information before the decompression, finally displayed it on the monitor.