Multimedia Based Online Collaborative Learning System

With the rapid development of information technology, the styles of obtaininginformation and spreading knowledge have greatly changed. Due to the lack ofcommunication, interaction and learners’ individual learning, the traditional classroomteaching mode no longer satisfies the needs of modern life-long education. While onlinelearning based on the Web2.0technology provides a learning environment withabundant education resources without restriction of time and space for learners, andpromotes the collaborative learning and resource sharing between them, which pointsout the development direction of education in the future.Through analyzing the requirements of online learning platform for learners, thispaper illustrates the functions and targets of the multimedia based online collaborativelearning system, which is divided into two parts: content-based video retrieval andonline learning community. First of all, we focus on video structuring, the keytechnology in content-based video retrieval. According to the characteristics of lecturevideos, shot segmentation is achieved by calculating neighbor frame difference with thecolor histogram, and key frame extraction is accomplished through the region shape ofelectric slides and the grey change property. Based on the structured video modelconstructed by XML data, the content-based video retrieval is realized. Meanwhile, thetechnologies to develop the system, such as ASP.NET, C#language, SQL Server2005database and Ajax, are introduced. The functions and database of this system aredesigned, of which development is completed. The system focuses on online learningproviding content-based lecture video retrieval for learners as well as supportingknowledge creation, communication and sharing. After the test, the interactivity andstability of the system has achieved the expected effect. In the end, some thoughts forthe expansion of the system are presented and the further research is put forward.