In this paper, we present a method to represent achromatic and chromatic image signals independently for content-based image indexing and retrieval for image database applications. Starting from an opponent colour representation, human colour vision theories and modern digital signal processing technologies are applied to develop a compact and computationally e-cient visual appearance model for...

The Coordinated Clusters Representation (CCR) is a texture descriptor based on the probability of occurrence of elementary binary patterns (texels) defined over a square window. The CCR was originally proposed for binary textures, and it was later extended to grayscale texture images through global image thresholding. The required global binarization is a critical point of the method, since thi...

Colour remains one of the key factors in presenting an object and, consequently, has been widely applied in retrieval of images based on their visual contents. However, a colour appearance changes with the change of viewing surroundings, the phenomenon that has not been paid attention yet while performing colourbased image retrieval. To comprehend this effect, in this article, a chromatic contr...

Structural colour in the Morpho butterfly originates from submicron structure within a scale and, for over a century, its colour and reflectivity have been explained as interference of light due to the multilayer of cuticle and air. However, this model fails to explain the extraordinarily uniform colour of the wing with respect to the observation direction. We have performed microscopic, optica...

Colour harmony was investigated using direct visual observations of computer simulated displays and compared with predictions of different colour harmony theories. Ou and Luo [1] constructed a model of colour harmony (CH formula) based on a harmony pair comparison experiment. The present paper compares our results with harmony predictions of the CH formula, and of colour harmony models based on...