Research Of Human-machine Interactive Large Screen Display System Based On CCD

Along with the computer science and multimedia technology progress, the human-machine interactive large screen display system is gradually becoming an essential conciliar or educational equipment. The interactive whiteboard is an important research direction in this area which synchronizes large screen projection technology with accurate position measurement technology to. Under a special application procedure support, it could create an alternant conference or teaching environment, in which we can operate computer arbitrarily by using a special pen instead of keyboard and mouse.At present, there are many kinds of methods used for realizing position measurement in both domestic and foreign markets. But for most of them, which need a special screen for displaying, it is difficult to produce large area, is costly. In view of the fact, two new ideas are presented to locate and trace the spot target, and both of them use low cost CCD devices for capturing image information. In the first method the position of the spot target is obtained by adopting real-time image processing technology while in the second one it is realized by using signal processing technology. The experiments are done on each of the two methods in the thesis, and the results are analyzed subsequently.In this thesis, the method based on real-time video image processing is introduced firstly, in this part, the format of YUV video data and video capturing method are fully introduced. In addition, it has been made that the rectification to correct geometric distortion caused by the inherent characteristic of optical lens, and polynomial warping and scale rebuilding method to do the experiment has been adopted. Moreover, the system principles and the process of overall system design are introduced in this part, the design scheme of CCD output signal processing circuit is discussed in detail, and the factors which affect the system precision have been especially analyzed. Finally, the whole work is summarized and the trend of the development of the whole system is discussed briefly.