基于输运方程的混合式体绘制模型

COMPOSED VOLUME RENUERING MODEL BASED ON TRANSFER EQUATION

作者从物理光学中输运理论的输运方程出发，在散射项的计算上，提出了体散射强度和面散射强度的计算，以及用边界因子组合该两项散射强度作为质点粒子在该点的总的散射光照强度的体绘制光照模型．该模型改变了目前体绘制所普遍采用的分割和计算光照强度分别进行的方法，将边界分割算子的值作为面散射强度的权结合到体绘制光照强度的计算中．作者将该体光照模型应用到超声波、ＣＴ和ＭＲ等体数据的直接体绘制上，其结果不仅提供了丰富的细节，而且具有清晰的隐含分界面．

Based on the transfer equation of transport theory in optical physics, a new volume rendering model. composed volume rendering model, is described.The calculating of scatter term is decomposed into the calculation of volume scatter intensity and surface scatter intensity, which are then composed with the edge detection operator. This model changes the most current volume rendering pipeline,which recognized the segmentation and illumination intensity calculation as two separated parts. In this model, the value of edge dection operator in segmentation is taken as the weight of surface scatter intensity in the composition of scatter illumination intensity. This model has been applied to the ray casting direct volume rendering of ultrasonic wave, CT and MR 3D data sets. The resultant images show not only rich details but also clear hidden surfaces.