Research On Key Technology Of Interactive Multimedia

The interactive multimedia system has been widely used because of its characteristics of good interaction and flexible operation. This paper taking multi-media teaching facilities as the main study object, through the key technology research, such as touchscreen technology and USB communication, solves the problem that the traditional multimedia system is lack of flexibility which blackboard writing has. The overall design of interactive multimedia system includes the design of Lower Computer platform and the design of Host Computer software platform. The design takes four-wire resistive touchscreen as the carrier, uses universal serial bus for the communication between Host Computer and Lower Computer, and designs a friendly man-machine interface in an integrated environment of VC++ 6.0. Universal Serial Bus can guarantee the A/D conversion information of touchscreen senting to Host Computer immediately, effectively and accurately. Touch-screen information processing and display, allows users to operate on the software platform freely, thus completing the interactive multimedia design.The design of Lower Computer includes the hardware circuit and microcontroller firmware programming. Hardware circuit uses ADS7843 and PDIUSBD12 to carry out circuit design of touchscreen conversion and USB interface. MCU firmware design focuses on the structure and the realization of firmware, HID class devices developing, report descriptors establishment and ADS7843 sampling program design.Software platform design of Host Computer, which is based on the MFC application framework, uses the object-oriented methods. This paper specifically describes the realization of the document and view for the basic vector graphics system, the logical coordinates and device coordinates conversion and the method of mouse interaction drawing graphic. And it achieves interactive drawing capabilities of line, continuous line, round, round regional and tagging texts.This paper completes the design goals of a combination for the multimedia classroom teaching and the traditional blackboard teaching, and enhances flexibility and interactivity of multimedia teaching. The design purpose achieves through the research on key technology of interactive multimedia. Test results meet the system requirements after the debugging and analysis.