The Application of DWT and SVD in Image Retrieval

Aiming at the color distributing feature of image, a feature extraction and image retrieval algorithm using Discrete Wavelet Transform (DWT) and Singular Value Decomposition (SVD) is proposed, which is based on child-block partition and area division. Firstly, divide the image into child-blocks, DWT the color value of each block, and extract the low frequency coefficients as the color feature of this block, and then divide the image into areas, some matrixes are composed with the DWT coefficients in this area, which are SVDed to gain the retrieval feature vector in order to compute the difference between images. Experiments show that the proposed algorithm reduces dimension well, obtains good recall and precision, and has good retrieval effect.