The Design And Realization Of Interactive Whiteboard Recording And Playback System

Sharing Interactive Whiteboard is a very important assistant teaching module of online teaching, which is widely used as an interactive and rich sense of visual communication tool.Recording and playback the process of Sharing Interactive Whiteboard painting with Online classes is very important aid to student's independent learning. The traditional way of recording in the Online classes is screen recording that formed video files. Students can't make any mark painting operations during playback so that this approach is taped purely one-way traffic. And the picture definition is very poor that severely affecting network classroom experience. The screen recording can cause the amount of data in recorded file and the high consumption of system resources.Focusing on the problem, Interactive whiteboard Recording and playback System is the solution to the shortcomings of a conventional recording and broadcasting applications. This thesis researches the Windows message mechanism and whiteboard technology and intercepts painting messages from the network and the local painting to recording in real time simultaneous forming recording file in a custom format. This thesis uses the cache mechanism to control the playback and designs the message playback synchronization mechanism and the high precise timers under Windows to control the accurately handle of painting message. This thesis introduces how to programs with the library of.NET to implement the function of drawing which provides the interface to the drawing message presentation,and finally describes how to realize the playback of graphics processing by drawing object containers. The system can show distortion-free operation of whiteboard interaction with a small footprint, while students can mark and paint at the time of playback.Interactive Whiteboard Recording and Playback System provides the function to record and undistorted playback the interactive painting process on the Whiteboard. The playback can be controlled by pause, resume, jumped and other control operations. Finally, the functional and performance tests verified the integrity of system functionality and the reasonability of design.