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K-NN框架下对小波系数补丁Kullback散度的图像检索

Image Retrieval via Kullback Divergence of Patches of Wavelets Coefficients in the k-NN Framework
课程网址: http://videolectures.net/etvc08_barlaud_irvkd/  
主讲教师: Michel Barlaud
开课单位: 尼斯索菲亚安蒂波利斯大学
开课时间: 2008-12-05
课程语种: 英语
中文简介:
本文提出了一个框架来定义图像处理中两个图像之间相似性(或相异性)的客观度量。问题是双重的:*定义一组捕获与给定任务相关的图像中包含的信息的功能,并*定义此功能空间中的相似性度量。在本文中,我们提出了一个特征空间以及对该空间的统计度量。我们的特征空间是基于图像在多尺度变换域中的全局描述。在分解成拉普拉斯金字塔后,系数被排列在尺度内/尺度间/通道间斑块中,这些斑块反映了存在特定结构或纹理时相邻系数的依赖性。在每个尺度上,这些补丁的概率密度函数(pdf)被用作相关信息的描述。由于多尺度变换的稀疏性,最显著的斑块称为稀疏多尺度斑块(SMP),能够有效地描述这些PDF。在比较这些概率密度函数的基础上,我们提出了一种统计测度(Kullback-Leibler散度)。有趣的是,这个度量是通过非参数k-最近邻框架估计的,而不显式地构建pdf。该框架通过实例图像检索方法应用于查询。对两个公开可用数据库的实验显示了我们的SMP方法在这项任务中的潜力。特别是,它与基于SIFT的检索方法和基于模糊分割的两种方法(UFM和CLEAK方法)进行了比较,对图像的不同几何和辐射变形具有一定的鲁棒性。
课程简介: This talk presents a framework to define an objective measure of the similarity (or dissimilarity) between two images for image processing. The problem is twofold: * define a set of features that capture the information contained in the image relevant for the given task and * define a similarity measure in this feature space. In this paper, we propose a feature space as well as a statistical measure on this space. Our feature space is based on a global description of the image in a multiscale transformed domain. After decomposition into a Laplacian pyramid, the coefficients are arranged in intrascale/ interscale/interchannel patches which reflect the dependencies of neighboring coefficients in presence of specific structures or textures. At each scale, the probability density function (pdf) of these patches is used as a description of the relevant information. Because of the sparsity of the multiscale transform, the most significant patches, called Sparse Multiscale Patches (SMP), describe efficiently these pdfs. We propose a statistical measure (the Kullback-Leibler divergence) based on the comparison of these probability density function. Interestingly, this measure is estimated via the nonparametric, k-th nearest neighbor framework without explicitly building the pdfs. This framework is applied to a query-by-example image retrieval method. Experiments on two publicly available databases showed the potential of our SMP approach for this task. In particular, it performed comparably to a SIFT-based retrieval method and two versions of a fuzzy segmentation-based method (the UFM and CLUE methods), and it exhibited some robustness to different geometric and radiometric deformations of the images.
关 键 词: 特征空间; 相似性度量; 概率密度函数; 稀疏变换
课程来源: 视频讲座网
最后编审: 2019-11-30:lxf
阅读次数: 52