三维(3-D)几何建模是计算机视觉的热点和难点,研究采用线性最小二乘特征向量估计法拟合二次曲面片参数方程,提出欧氏变换下不变几何特征的提取技术,分析了物体表面的特征关系图(ARG,attribute relation graph)表达法,利用激光点云,基于二次曲面片与ARG实现了似二次曲面物体的3-D几何建模。
3D geometrical modeling is a hot and difficult problem in computer vision.the parameter equation of quadric patch is fitted by adopting the eigenvector estimate method of linear least squares.Second the extracton technology is expounded for differential coefficient invariable geometry attributes,such as curvature average value and entropy of curvature distribution,and the movement invariable geometry attributes,such as 0-order and 2-order 3D movement invariant of quadric patch.Third expression method of objects surface is analyzed based on attribute relation graph(ARG),the character value of each quadric patch and the relations among quadric patches are computed.Finally the ARG of whole surface of the points cloud model is built and the 3D geometrical modeling is completed with quadric patch and ARG by using laser points cloud.