Spatial Arrangement of Color in Retrieval by Visual Similarity

In image search based on chromatic similarity, the effectiveness of retrieval can be improved by taking into account the spatial arrangement of colors. This can serve both to distinguish images with the same colors in different arrangement, and to capture the similarity between images with different colors but similar arrangements. We propose a model of representation and comparison which attains this goal by partitioning the image in separate entities and by associating them with individual chromatic attributes and with mutual spatial relationships. The effectiveness of the proposed model is assessed in a user-based evaluation. Experimental results show the capability of the model to join and balance chromatic and spatial similarity, thus improving the effectiveness of retrieval with respect to representations based on a global histogram.