为了在普通微机上实现对医学体数据场的实时清晰绘制,给出了一种多种因素融合的光学属性赋值方法,进而提出一种新的医学体绘制算法。将医学体数据场进行分类,对于前景体素集采用LOD(Layer of Detail)技术进行重采样;然后用定义的光学属性赋值方法对采样点赋值,从而将物体距离视点的距离与物体距离光源的距离有效地结合起来。最后,采用基于空间跳跃的加速技术显示背景体素。实验结果表明:对于512×512×482×2 Byte大小的体数据在减少至原来大小2/3的情况下,在普通微机上能够达到2.5 frame/s的清晰绘制。本算法能够实现一般大小体数据场的实时绘制,而且组织器官显示清晰,符合人的视觉特征。

In order to realize real-time rendering for medical images on PCs,a scheme combining multi factors for assigning optical attribute to resampling points is defined,and then a novel rendering algorithm for medical volumetric data is presented.The volumetric data are classified into the foreground voxels and background voxels,and the foreground voxels are resampled using Layer of Detail(LOD) technique.Then,the optical attributes of resampling points are determined by the defined method,which is reasonably associated with the distances between object and viewpoint,as well as object and light source.Finally,the background voxels are displayed by the accelerated method based on space leaping resampling.The experimental results indicate the presented algorithm can reach up to 2.5 frame/s clearly on PCs for 512×512×482×2 Byte volumetric data,when it reduced to 2/3 times of the original size.It comes to the conclusion that the interactive volume rendering can be implemented for most medical volume data on PCs.Moreover,tissues or organs can be displayed clearly,which is more coincident with the human vision.