基于分段积分的医学体数据剖切绘制算法  

Piecewise integration based rendering and clipping for medical data

作　　者：李冠华[1] 欧宗瑛[1] 韩军 赵德伟[3] 王卫明[3] 

机构地区：[1]大连理工大学精密与特种加工教育部重点实验室,辽宁大连116024 [2]大连现代高技术公司,大连 [3]大连大学附属中山医院,大连

出　　处：《光电子．激光》2008年第9期1269-1273,共5页Journal of Optoelectronics·Laser

基　　金：国家“863”高技术研究发展计划资助项目(863-306-ZD13-03-6);大连市科技计划资助项目(2005E21.SF134)

摘　　要：提出一种抛物线插值的体绘制分段积分方法,并改进了基于剪切几何纹理化的体数据剖切绘制。首先将采样段内的颜色值用抛物线插值近似代替,计算各采样段的光强值,代替采样点用于体绘制积分方程,即使低采样率下仍能获得较好的图像质量。对体数据进行剖切绘制时,与传递函数相结合,根据剪切几何形状和位置修改体数据中的相应体素值,使之对最终绘制图像不作贡献,达到剪切绘制的目的,并实现了基于剪切几何和基于体数据阈值分割的剖切算法。试验结果表明,本文方法明显提高了绘制图像的质量,降低了剖切绘制时的内存使用,同时提高了剖切绘制的速度。A novel piecewise integration is proposed for direct volume rendering and the algorithm of dipping is improved based on volumetric textures, Firstly, the intensity of each sampling segment is computed with parabola interpolation for colors within each segment,and then instead of the intensities of the sampling points,the intensities of the sampling segments are used for direct volume rendering function The improved clipping method combines the volumetric textures of clipping geometry with transfer function. When the volume data is clipped,voxels are reset according to the clipping geometry shape and position so that they have no contribution to the rendered image, Clipping algorithms based on clipping geometry and threshold segmentation are realized respectively in the paper, The experiments show that our methods can improve the quality of rendered image greatly, and the clipping rendering speed is increased,

关 键 词：直接体绘制 分段积分 体数据剖切 可编程图形硬件 

分 类 号：R318.51[医药卫生—生物医学工程]