面向3D动画球幕电影的鱼眼图像制作方法

Method for Making Fisheye Images for 3D Animated Dome Shows

近年来,随着3D动画球幕电影的需求量不断提高,需要解决使用3D动画软件制作鱼眼图像存在的功能少、效率低等问题。基于球幕电影定义的等距鱼眼投影的数学模型,针对不同规格球幕影院的放映需求,利用虚拟球面变换,提出了制作鱼眼图像的具体方法和实现步骤。首先,将二维鱼眼图像中的每个像素映射到三维虚拟球面上,针对不同剧场放映特点,对球面坐标进行变换,再将球面坐标与3D动画空间坐标建立映射关系,最后对生成鱼眼图像进行抗锯齿处理优化。该方法可以通过编写可执行程序或者3D动画软件插件的形式实现,可调度CPU或GPU执行。使用该方法已参与完成制作多部球幕电影,并在国内外多个球幕影院中播放,能够有效地还原3D动画中所制作物体的形状比例,无任何扭曲,且使用场景灵活,易并行。

In recent years,with the increasing demand for 3D animated dome shows,there is a need to solve the problems such as few functions and low efficiency of using 3D animation software to produce fisheye images.Based on the mathematical model of equidistant fisheye projection defined by dome shows,the concrete method and realization steps of fisheye image production are put forward by using virtual sphere transform to meet the projection requirements of different specifications dome theaters.Firstly,each pixel in the 2D fisheye image is mapped to the 3D virtual sphere,the spherical coordinates are transformed for the projection characteristics of different theaters,the mapping relationship is then established between the spherical coordinates and the 3D animation space coordinates,and finally the generated fisheye image is optimized by anti-aliasing.The method is implemented through executable programs or 3D animation software plugins that can be scheduled for CPU or GPU.Using this method,we have participated in the production of several dome movies,and played in many dome theaters at home and abroad,which can effectively restore the shape proportion of the objects produced in 3D animation without any distortion,and the use of scenes is flexible and easy to parallel.