Rotation-invariant texture feature for two-stage image retrieval
Yahui Wu · Guangdian gongcheng · 2005
A method used for two-stage image retrieval with rotation-invariant texture feature is proposed against the common rotation problem of image. In coarse retrieval, the image is converted into a rotation-invariant but row-shifted image through polar transform. The approximate row-shifted invariant wavelet feature is extracted. Combined with coarse comparison algorithm, a coarse retrieval will be carried out for the whole image database to remove undesired images. The image after coarse retrieval will be processed through Gabor transform and a rotation-invariant feature will be got to perform the fine matching. The similarity is measured by Canberra distance. The results show that the method speeds up operation speed. When suitable parameters are selected under conditions of the same feature, its retrieval ratio has been improved for 1.625% higher than that of the fine retrieval method.