基于CT扫描图像的砂岩石三维建模研究  

Research on 3D Modeling of Sandstone Based on CT Scanning Images

作　　者：黄贤胜 成卫青[1] 林伟 熊生春[2] HUANG Xian-sheng;CHENG Wei-qing;LIN Wei;XIONG Sheng-chun(School of Computer,Nanjing University of Posts and Telecommunications,Nanjing 210023,China;Institute of Porous Flow and Fluid Mechanics,Chinese Academy of Sciences,Langfang 065007,China)

机构地区：[1]南京邮电大学计算机学院,江苏南京210023 [2]中国科学院渗流流体力学研究所,河北廊坊065007

出　　处：《计算机技术与发展》2020年第7期115-119,共5页Computer Technology and Development

基　　金：国家自然科学基金(61170322);国家科技重大专项项目(2017ZX05013-001)。

摘　　要：为了得到岩心的快速成型文件,首先对采集到的致密砂岩岩心进行CT扫描,得到二维CT序列图像。初步介绍了VTK工具库和标准三维模型的格式文件-STL文件,阐述了三维建模的经典算法-MarchingCubes算法,了解了它的基本原理。然后通过获取到合适的阈值,基于形态学方法对CT图像进行数次膨胀和压缩处理,去除图像的虚边,并进行分层灰度化和背景切割等预处理操作。对MarchingCubes(MC)算法中的插值运算进行了简化,采取的方式是将体素边分为四等份,提取四等分点使得三角面片顶点坐标和法向量分量值的计算量大幅减小,利用改进后的MC算法对预处理后的图像进行三维重构,生成三维模型和STL文件。实验结果表明,改进后的MC算法能够提高三维建模的效率,重构出的模型也保持了相当高的精度。In order to obtain the rapid prototyping file of the core,the CT scan is performed on the collected tight sandstone core to obtain the 2 D CT sequence image. The format file of the VTK tool library and the standard 3 D model-STL file is introduced,and the MarchingCubes algorithm,a classical algorithm for 3 D modeling,is expounded and its basic principles are understood. Then,by obtaining the appropriate threshold,the CT image is expanded and compressed several times based on the morphological method to remove the virtual side of the image and perform preprocessing operations such as layered graying and background cutting. The interpolation operation in the Marching Cubes(MC) is simplified by dividing the voxel side into four equal parts and extracting the four equal points to make the calculation of triangular surface vertex coordinates and the normal vector component value significantly reduced. The improved MC algorithm is used to reconstruct the preprocessed image in three dimensions to generate a three-dimensional model and an STL file. The experiment shows that the improved MC algorithm can improve the efficiency of 3 D modeling,and the reconstructed model also maintains a high degree of precision.

关 键 词：三维建模 MC算法 形态学 VTK工具库 STL文件 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]