小波域Copula 多维模型纹理检索

Abstract

In this paper, an effective texture retrieval method using copula multidimensional model on wavelet domain is proposed. For make up for the shortcomings of the single statistical model on wavelet subband, a treedependence structure on wavelet domain is constructed, and copula multidimensional distribution is implemented on the tree-dependence structure of wavelet domain. Tree-dependence structure can capture both the dependences of inter-scale and neighbor-dependence structures, and it has fewer dimension and fewer number of copula models comparing to the neighbor-dependence structure. Because of the complexity of the copula multidimensional model, it is difficult to deduce the Kullback-Leibler distance (KLD) of copula model. This paper puts forward a kind of retrieval method based on KLD of copula multidimensional model, which is consisted of two components: The KLD of marginal distributions and the KLD of copula function. The experimental results on VisTex and Brodatz databases show that the proposed retrieval method has low computational complexity and high retrieval accuracy, and it is more effective than the state-of-the-art copula methods on wavelet domain. The proposed texture retrieval method can be extended to other wavelet domains such as complex wavelet and directional wavelet domains.