CVPIC image retrieval based on block colour co-occurance matrix and pattern histogram

Compressed domain image processing techniques are becoming increasingly important. Compressed domain retrieval allows the calculation of image features and hence content-based image retrieval (CBIR) to be performed directly on the compressed data without the need for decoding it beforehand. The colour visual pattern image coding (CVPIC) technique represents a compression algorithm where the compressed form is directly meaningful. Based on CVPIC, we introduce a compressed domain retrieval algorithm that makes immediate use of the fact that colour and pattern information is readily available in the CVPIC domain. Colour features are exploited by building a block co-occurance matrix of colour indices while shape information is represented through pattern histograms. Combining these two types of descriptors results in an efficient and effective image retrieval method that even outperforms popular pixel-based algorithms such as colour histograms, colour coherence vectors and colour correlograms.