基于单指令多数据流扩展的光线投射算法优化

Optimization of the Ray-casting Algorithm Based on Streaming Single Instruction Multiple Datum Extension

光线投射算法是目前医学图像可视化领域应用范围最广、成像效果最好的算法之一。由于大量的采样、梯度、光照和混合计算,所以该算法的运算开销也比较大。单指令多数据流扩展(SSE)指令集支持向量计算可以很好的支持光线投射算法的特性,通过将梯度、光照和混合计算向量化,不仅可以明显提升算法的执行效率,而且可以绘制出高质量的可视化结果。

At present,ray-casting algorithm is the most widely used algorithm in the field of medical image visualization,and it can achieve the best image quality.Due to large amounts of computation like sampling,gradient,lighting and blending calculation,the cost of ray-casting algorithm is very large.The characteristic of Streaming single instruction multiple datum extensions（SSE） instruction-supporting vector computation-can satisfy the property of ray-casting algorithm well.Therefore,in this paper,we improved the implementation efficient significantly by vectorization of gradient,lighting and blending calculation,and still achieved a high quality image at the same time.