【作者】 白生祥；

【导师】 陈戈；

【作者基本信息】 中国海洋大学 ， 信号与信息处理， 2008， 硕士

【摘要】 随着计算机和多媒体技术的发展,具有人机交互功能的投影大屏幕显示系统逐渐成为不可或缺的会议辅助或教学设备。融合了大屏幕投影技术、精确定位技术等的交互式电子白板是这种人机交互系统的一个重要发展方向。在专门的应用程序的支持下,它可以构造一个大屏幕、交互式的协作会议或教学环境,可以利用特定的定位笔取代键盘和鼠标随意操控计算机。现阶段的国内外市场上,有多种技术可以实现电子白板精确定位,但大都需要专门的显示屏幕,难以实现超大面积且均成本高昂。鉴于此点,本文提出了两种新的设计思路,它们均采用低成本的CCD器件采集投影大屏幕的图像信息。其中,思路一是采用图像处理技术,由处理采集的实时图像信息实现定位;思路二是根据全电视信号的特点,设计专门的信号处理电路实现定位。对两种思路,本文分别搭建了相应的试验系统,进行了原理实验,并对实验结果做了分析。首先,本文详细阐述了基于实时视频图像处理的实现方案,介绍了视频采集的方法和视频数据的存储格式,并对系统性能进行了分析。其次,文中深入探讨了光学镜头产生几何畸变的原因和畸变校正的原理,采用多项式拟合法实现了畸变的校正,并对两种不同的灰度插值方法得到的校正结果进行了比较。再次,本文介绍了基于CCD全电视信号处理的定位技术原理,全面分析了CCD器件输出的黑白全电视信号的特点和串行通信格式。在此基础之上,重点介绍了全电视信号处理电路的设计方案并对实验中会导致定位误差的各因素作了分析。最后,论文总结了整个实验过程,并对尚待完善的地方作了分析展望。更多还原

【Abstract】 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.更多还原