【作者】 童小红；

【导师】 秦新强；

【作者基本信息】 西安理工大学 ， 应用数学， 2005， 硕士

【摘要】 随着计算机图像处理技术的发展,使得医学图像的三维重建变得可能,并逐渐成为目前的一个新的研究热点。医学图像三维重建是一个多学科交叉的研究领域,是计算机图形学和图像处理在生物医学工程中的重要应用。它涉及数字图像处理、计算机图形学以及医学领域的相关知识。医学图像三维重建及可视化在诊断医学、手术规划及模拟仿真、整形及假肢外科、放射治疗规划、解剖教学等方面都有重要应用。因此,对医学图像三维重建的研究,具有重要的学术意义和应用价值。 本文研究了医学图像三维表面绘制的两种方法及其基本原理,对基于规则体数据抽取等值面的经典算法Marching Cubes(简称MC)方法进行了详细的讨论。MC算法存在重建速度慢、数据存储冗余等缺点。对此提出了对标准MC方法的改进。第一个改进是:在等值面上样本点的状态依赖于它所连接的边同等值面相交的数目;第二个改进是:两相邻样本点中等值面多边形顶点被定位于中点,使得共面三角片合并为一个多边形;第三个改进是:用等值面的多边形连接方法代替三角形连接方法从而减少了生成多边形的数量,减少了生成多边形的数量,提高了算法效率。实验结果表明本文提出的算法加快了MC算法的速度,显示结果几乎没有差别。更多还原

【Abstract】 With the development of computer image processing technology, 3D reconstruction of medical image is possible, and being a new research hotspot gradually. 3D reconstruction from medical images is a multi-disciplinary subject. It is an important application of computer graphics and image processing in biomedicine engineering. It relates to the subjects of digital image processing, computer graphics and some related knowledge of medical. 3D reconstruction and visualization of medical images are widely used in diagnostic, surgery planning and simulating, plastic and artificial limb surgery, radiotherapy planning, and teaching in anatomy. Study on 3D reconstruction from medical images has important significance on science and worthiness in practical application.This paper introduces two methods of 3D medical image surface rendering and the principle, and gives a detailed study on the Marching Cubes algorithm which is a classical algorithm to extract iso-surface from regular volume data. Marching Cubes algorithm has disadvantages of low reconstructing speed and data redundancy. An algorithm is presented to improve this algorithm performance. It modified the standard Marching Cube algorithm by two ways. The first modification is that the status of a sample point on the iso-surface depends on the number of edges intersected by the iso-surface. The second modification is that polygon vertices between two adjacent sample points arelocated at the middle point, which leads to co-planar triangles being merged into a polygon. The third modification is that the generated triangles are substituted by polygons. Thus reduces the number of polygons generated and increases the efficiency of the Marching Cube algorithm. The experiment results show that this algorithm accelerates the speed of Marching Cubes algorithm and the difference of the display performance is little.更多还原