基于映射的复轮廓波变换纹理图像检索系统

Mapping based complex contourlet transform texture image retrieval system

轮廓波变换纹理检索系统检索率比较低的根本原因在于轮廓波变换域系数的振荡性和移变敏感性。为了克服轮廓波变换的这些缺陷,提出了一种基于映射的复轮廓波变换。在该变换的基础上,采用变换域子带系数的能量和标准偏差序列作为特征向量,以Canberra距离为相似度度量标准,构造了一种纹理图像检索系统。实验结果表明,在特征向量长度、检索时间、所需存储空间基本相同的情况下,基于映射的复轮廓波变换检索系统比轮廓波变换检索系统具有更高的检索率。

The ultimate reason of low retrieval rate of contourlet transform texture image retrieval systems lies in the coefficients oscillating and shift sensitive characters. In order to overcome the defects of contourlet transforms, a mapping based contourlet transform is proposed, and a texture image retrieval system based on the new transform is proposed in which the feature vectors are formed by cascading the energy and standard de- viation of each sub-band in the mapping based contourlet domain, and a Canberra distance is used as similarity metric. Experimental results show that the image retrieval system is superior to that of the original contourlet transform with almost same length of feature vectors, retrieval time and memory.