Study Of Volume Rendering Based On Medical CT Images

The visualization of medical images is an important application of scientific visualization in the medical field. It is a research hotspot in medical image processing at present. There is great applied prospect in medical research and clinic diagnosis using medical visualization. The purpose of visualization in medical images is to reconstruct 3D image models with 2D medical slice images by 3D visualization technologies. Meanwhile, it is to rebuild visual videos and lay out 3D configuration of human organs for further qualitative and quantitative analysis preferably.The courses of data preprocessing and accelerated rendering were studied and discussed deep in this paper. Surrounding the present basic theories and classical algorithms, some primary methods were improved and new algorithms were put forward, based on the 3D data sets of medical CT images sequence provided by Visible Human. Furthermore, the speed of rendering and the quality of result images have been improved.Filtering and interpolation are basic operational units in volume rendering of medical images. Median filtering and tri-interpolation are in common use. An effective and accelerated median filtering was presented and the tri-interpolation algorithm was improved. Meanwhile, based on several accelerated techniques of DVR, an efficient ray-casting algorithm was presented which improves the traditional ray casting algorithm. The algorithm mainly applies methods of polygon scan conversion and voxelization of casting rays. At the same time, the algorithm uses the method of determining the convex hull of a set and the intersectingalgorithm related directly to x, y, z family planes to clip data sets and rays.