Design And Implementation Of Rich Media Client Based On LASeR

With the development of multimedia technology, increasing bandwidth, the increasing number of mobile end-user, people's demand of experience became higher and higher. Rich media technology, with its rich forms of media content and real-time interactive experience, became the solution of the problem. this article analysised the basis of the rich media theory and technology in detailed, began the discussion to the implementation of the rich media client greatly, provided some practical consultation.Firstly, the rich media concept and the relationship of rich media technology with multimedia technology have been descibed, then provides the architecture of the rich media service. The SVG technology which provides the organizing methods of multiple media contents based on XML and the LASeR specification published by MPEG have been introduced. LASeR specification defines the scene description language and the update mechanism, specify the code description, spatial layout, timing initial synchronization and the modes of scene change. By the analysis of the LASeR related specifications and the typical process in rich media service, we concludes the functional requirements of the rich media client.Based on the analysis of rich media client functional requirements, we makes an logic abstraction into various fuctional modules. Considering the cooperating relationship among different modules, the graphic element tree module has been designed which wraps the public elements and operations of the DOM Tree, which reduces coupling between modules and brings a good software scalability. We also designes a event handling mechanism including event and adapter's definition to the handling of javascript with an enhancement of the client interaction and the quality of user's experience.In integrated development enviroment of Eclipse, all the modules such as the user interface layer,SVG displaying layer,graphic element tree layer and the scene parsing layer have been implemented by dint of batik toolkit, which is coded in java language. At last, with the integration of aboved modules, we buildes the rich media client in which not only the SVG scene tree can be rendered and the real-time interactive javascript event can be supported.Further more, by the construction of the simplied rich media server, we do the functional and performance testing to the client. Also, we analyze some shortcomings in the rich media client and point out the next research direction.