基于二维希尔伯特变换的相位一致模型图像特征检测方法  

The Algorithm of Image Features Detection from Phase Congruency Model Based on 2-D Hilbert Transform

作　　者：王珂[1] 肖鹏峰[1] 

机构地区：[1]南京大学地理与海洋科学学院地理信息科学系,南京210093

出　　处：《测绘学报》2010年第6期605-610,617,共7页Acta Geodaetica et Cartographica Sinica

基　　金：国家863计划(2008AA12Z106);国家自然科学基金(40801166;40771137)

摘　　要：相位一致方法是从频域中的相位信息理论中延伸出的一种图像特征检测方法。其原理是指图像特征如跃级边缘、线形、屋脊形和马赫带等,总发生在相位的最大叠合处。该原理通过构造局部能量模型,并经标准化后,度量其图像各个位置的相位一致值。在前人的基础上对该模型进行改进,提出以二维的希尔伯特变换代替一维希尔伯特变换,从而在全方向上考虑各点的相位一致。改进算法后,相位一致模型的分子部分,即局部能量,是利用去DC(Direct Current,直流)分量算子和二维希尔伯特变换算子以卷积的形式求取,从而简化算法实现过程。同时为了抑制噪音的影响,在相位一致模型中的分母部分中引入了图像DC分量。最后以自然图像和遥感图像为试验对象进行图像特征检测,结果表明该改进方法可以有效地提取图像特征。The algorithm of phase congruency developed from phase information of image in frequency domain,is employed for image feature detection.The theory of phase congruency is that image features,such as step edge,roof,Mach band and delta,always occur at points where the phases of harmonic components come to the maximum congruency.This algorithm is realized to extract the image features by constructing the local energy model being normalized to get the value of phase congruency of every point in image.This paper introduces the 2-D Hilbert transform instead of 1-D Hilbert transform to propose the algorithm of phase congruency for detecting the image features.The modified algorithm can take account of the full directions of the image features.Meanwhile,the proposed method simplifies the calculation of the numerator of local energy by convoluting the original image with the window operator to remove DC（Direct Current） component of current window and 2-D Hilbert transform respectively.Moreover,this algorithm makes the denominator of the model of phase congruency adding the DC component to suppress the noise of image.The modified algorithm of phase congruency is implemented into the natural image and remotely sensed imagery,and the results show that the modified algorithm is effective to detect image features.

关 键 词：相位一致 二维希尔伯特变换 局部能量 图像特征检测 

分 类 号：TP751.1[自动化与计算机技术—检测技术与自动化装置]