基于协方差矩阵的仿射不变量  

Affine Invariants Based on Covariance Matrix

作　　者：刘亦书[1] 

机构地区：[1]华南师范大学地理科学学院,广东广州510631

出　　处：《小型微型计算机系统》2007年第7期1282-1286,共5页Journal of Chinese Computer Systems

基　　金：广东省自然科学基金博士启动项目(04300033)资助.

摘　　要：为了对仿射变形的物体进行有效和正确的识别,构造了一种新的仿射不变量.构造的主要过程是:先计算图像的协方差矩阵,接着计算该矩阵的特征值和特征向量,再构造出一组同心椭圆,这些椭圆以图像质心为中心,以两个特征向量为长、短轴,且轴长和两个特征值的平方根成正比,进而利用图像紧化原理和仿射变换的有关性质推导出一组仿射不变量.文中将仿射不变量用于模式识别,获得很高的识别率.The feature-based recognition of affine-deformed objects is important and challenging in pattern recognition and computer vision, finding efficient features which are invariant under affine transformation is the key to solving this problem. This paper concentrates on deriving such features as mentioned above, i.e. affine invariants. The covariance matrix of a given image is computed first, then its＇ eigenvalues and eigenvectors are calculated, with that a set of ellipses with the same center are constructed, lastly a set of affine invariants are derived based on image compactification theory and some properties of affine transformation. Numerical experiments are carried out and show that the performance of our affine invariants is promising.

关 键 词：协方差矩阵 仿射变换 仿射不变量 特征值和特征向量 紧化 椭圆 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]