Medical Image 3d Visualization Technology Research

3D visualization for medical image is currently one of a hot problem in computer graphics and is an important foundation of digital virtual human. In medical field, visualization for medical image series can obtain 3D image of organ which can aid surgeon to diagnose, plan or simulate surgical. Therefore, it is profound to research 3D visualization technology. This paper mainly research several key problems on visualization, including image preprocessing, visualization algorithm, 3D clipping and surgical simulator.In image reprocessing, this paper focuses on image segmentation. Because automatic image segmentation algorithm can not achieve ideal result, we present an interactive segmentation algorithm based on level set or active contour model. First this method segments several images by hand or by combination automatic segmentation with hand. Then, according to the analogy of adjoining medical image, the method segments adjoining image using level set or active contour model. Experiments show this algorithm achieves fast and accurate segmentation results.As for visualization algorithm, this paper mainly researches direct volume rendering (DVR) technology, introduces principle of DVR, analyzes and compares several DVR methods. Transfer function plays a key role in DVR. However, it is difficult to design a proper transfer function. In this paper, we introduce and analyze several methods for transfer function designing and experiment a method based gray or gradient histogram and improve it.In order to observe inner structure of volume data better, it is necessary to clip volume data. This paper proposes an interactive 3D clipping methods. The method firstly initiates a 2D or 3D clipping geometry. Then user can translate, rotate, zoom in or zoom out it. Asa result, the clipping geometry arbitrarily intersect with volume data. This method can be easily implemented.At last, this paper briefly analyzes virtual surgical system. This system has great perspective in clinic and medical education. However, many key technologies need to further research in order to implement it. With the development of technology, we believe it will be come into true.