An Improved Fast Ray Casting Volume Rendering Algorithm of Medical Images*

摘要

Ray casting algorithm is widely used in three-dimensional visualization of medical image, which can produce superior quality image besides simple theory. However, its rendering velocity is very slow because of huge amounts of rays and repeated resample of the data. An improved fast algorithm of ray casting volume rendering is presented which can figure out composition segment fleetly and reduce interpolation calculation by intersection point computation of the ray and a family of planes. The re-sampling speed is improved by taking advantage of segment composition method. And the efficiency of ray casting is increased greatly by utilizing boundary box technique which avoids intersection point computation with useless planes. The experiment results show that the improved acceleration algorithm can produce the required quality images, at the same time reduce the total operations remarkably, and speed up the volume rendering.