基于真实环境图象的三维动态仿真系统研究

针对在城市规划中，建筑设计方案的计算机三维图形与真实环境图象进行匹配及合成的问题，研究和提出了一种基于摄影测量学返透视原理的，对实际环境摄像经抽样采集的图象序列进行亮度、方差及平均色度合成的图象分析方法，并研究了一种基于单象空间后方交会解析摄影测量技术一阶渐近迭代计算的求解虚拟摄像参数的算法，同时提出了基于关键帧技术的适合于图象合成时，计算分割区域随时间变化的动态掩模算法，还在太阳系行星运动规律的基础上，建立了适合于计算机虚拟三维世界坐标系的日照模型，以及相应的求解任意时刻、任意经纬度虚拟世界坐标位置处的虚拟太阳光源方向和强度的算法。这些算法已被应用到基于真实环境图象的三维动态仿真系统中，实验结果表明，这些算法是行这有效的。

3D Dynamic Simulation System Based on Real Environmental Images

The investigation of the problem that concerns the match and composition between the virtual 3D computer graphics or image for the architecture planed to build and the real environment image sequence has been carried out. The major research way is to make anti-perspective calculation on the image sequence extracted from the video clip about the real environment based on photogrammetry and make analysis of lighteness, average square error and average chroma on the image sequence. The algorithm has been studied to get the parameters of the virtual camera by calculating out the parameters of the real camera with linear asymptote iterative calculation based on the technology of single photo analytical photography in photogrammetry. The algorithm of dynamic masking has been put forward to synthesize virtual image sequence and real environment image sequence based on keyframe technology when the segmentation edge varies with time. The model of virtual sunlight in computer' s virtual 3D world coordinate space has been established based on the rules of the elliptical motion of planet in the solar system and the rules of earth' s rotation to simulate the sunlight at any time in a year and in any position with arbitrary longitude and latitude in the world. These algorithms have been applied to the 3D dynamic simulation system based on real environment images. The result of experiments proves that these algorithms are effective.