Combining wavelet saliency, color and DCT coefficients for content-based image retrieval

Abstract

This paper presents an approach for content-based image retrieval extracting salient points and regions from images, and also aggregating color and DCT values in a signature descriptor for recognition. Salient points and regions are extracted from each image by a wavelet decomposition over the color channels where the highest coefficients in coarsest levels are the centers of salient regions in finest resolution. These local regions are support for extracting color histograms and a set of DCT magnitudes in order to derive a signature for the image. A feature vector combining histograms of color channels and DCT values is proposed and tested as signature of the image. Public COIL, Caltech, and ZuBuD images datasets are used for testing. Results comparing variations of the descriptor based on wavelet saliency are given on all those image datasets supporting potential for the proposed method.