Compressed Domain Image Indexing and Retrieval Based on the Minimal Spanning Tree

In this paper, a method for content-based retrieval of JPEG images is presented, utilizing features directly from the discrete cosine transform (DCT) domain. Image indexing is achieved by extracting color and texture feature vectors, using an efficient technique applied on the DCT coefficients. Similarity between the query- and database-images is provided based on a statistical graph matching approach. The proposed measure makes use of the Wald-Wolfowitz test, a nonparametric test that assesses the commonality between two different sets of multivariate observations. Experimental results demonstrate the enhanced performance of our approach, compared to previously reported methods