【作者】 赵猛；

【导师】 金一丞；

【作者基本信息】 大连海事大学 ， 交通信息工程及控制， 2010， 博士

【摘要】 随着计算机图形图像技术的发展,仿真系统中单视点图像所营造的虚拟环境使人觉得越来越不能满足需求。用户希望像真实环境中一样能够感受到虚拟场景中的物体与用户之间以及物体之间的相对深度信息,于是立体显示技术逐渐被引入到大屏幕多人沉浸式仿真系统应用当中。本文结合人眼在真实环境中建立立体视觉的生理过程,分析了基于双目视差模型的平面幕立体显示的生理局限性,为了使生成的双眼图像视差在人眼的可融合范围内,提出了双眼图像间的视差控制方法。根据给定显示设备和虚拟场景的尺度,提出了一种精确计算虚拟相机分离距离的方法,该方法可以适用于不同的物理显示设备和不同尺度的虚拟场景模型。提出采用分割场景深度的方法,使近景物体映射到物理屏幕较大的融合范围内,从而增大近景物体的深度感知范围。搭建了大屏幕多人沉浸式CAVE立体显示系统,给出了适合于工程上搭建“经济型”CAVE系统的几种实现方法。提出了一套适用于CAVE的图像几何校正方法,通过重投影变换计算出B样条曲面控制点坐标并且绘制B样条曲面,将预存在纹理内存中的双眼视景图像分别映射到各自的B样条曲面上。通过对左右眼立体图像分别进行几何校正,实现了CAVE多通道立体显示的无缝拼接。通过调整B样条曲面的控制点坐标以及曲面阶数,实现了左右立体图像局部位置的调整以及图像平滑度的调整。CAVE系统作为六自由度仿真器的仿真环境支持平台,针对其视坐标系的建立,提出了初始VUP矢量的概念,将初始VUP矢量绕n矢量的旋转与虚拟相机横摇角的概念联系起来,由此得出任意VUP矢量的计算方法。作者将基于CAVE系统的多通道立体显示技术成功地应用在直升机模拟器和集装箱装卸仿真系统中。更多还原

【Abstract】 With computer graphic technology continuing to develop, the virtual environment created by single-view images can not meet the requirement of users. Users want the virtual environment as the real world where the relative depth information between virtual objects and users or between virtual objects can be felt. Thus, stereo display technology has been gradually introduced into the application of large screen, muti-user and immersive simulation system.Compared with the physiological processes of establishing stereo vision in real world by human eyes, physical limitations of stereo displaying on screen based on binocular parallax models is analyzed. In order to generate parallax of two eyes images within the fusion area, parallax control methods are proposed. According to the given display device and the scale of the virtual scene, a precise calculation method of the virtual camera separation distance is given. The method can be applied to different physical display devices and different scale models of the virtual scene.The paper puts forward a way to split the scene depth. With the method, close-range objects can be mapped to the the larger fusion area of physical screen.Thereby the scope of close-range depth perception of objects is increased. The CAVE stereo display system is bult. Several ways suitable for projects on constructing stereo display system based on economical cave are given. A calibrating method suitable for CAVE is proposed. According to the reprojection, we calculate the control points, render the B-spline surfaces and map the textures to the B-spline curved surfaces of two eyes respectively. Thus, by calibrating geometry of two eyes images respectively, seamless joining is implemented in multi-channel stereo displaying system of CAVE. The position and smoothness of partial image can be calibrated by fine turning of control points and order of B-spline curved surfaces. For the construction of view coordinate system in the CAVE system which serves the six degrees of freedom simulatior, the concept of the initial vector VUP is proposed, and we establish contact between the roll of the analog camera and the initial vector VUP which rotates around the vector n. Then the general calculation method of the arbitrary vector VUP is deduced. At last, the application of multi-channel stereo displaying technology based on CAVE is successfully applied to helicopter simulator and container crane loading simulation system.更多还原