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Perceptual Colour Features for Natural Scene Image Description and Retrieval

In this paper, we propose new image features called perceptual colour features. The features are based on twenty basic colours called emotional colours, which are used to describe the relationship between colours and emotions in psychological studies. We analyzed a colour image in L*a*b* and L*C*h colour spaces to link to emotions. Then, the perceptual colour features are derived from the histogram of the twenty emotional colours. We have demonstrated effectiveness of the perceptual colour features with an emotion based image retrieval application. Experiments were performed on a set of impressive natural scene images. The retrieval results were analyzed by both objective evaluation and subjective evaluation. The results revealed that the proposed perceptual colour features outperformed the conventional colour histogram features both in terms of precision and consistency with users' perception.