Theory of Colour Harmony and Its Application

The colour represents an essential element of visual and graphic communications. It plays an important role in the perception of visual design and it is significant for all participants in the process of planning, developing and promoting graphic products. Designers are interested in a psychological and presentational aspect of colours, while to the technologists the colour represents one of the most important quality attributes. The process of choosing colours that are harmonious, usable and efficient is complex. In addition, many designers have inadequate background knowledge of colour theory, which could help them with the selection of colours. As a result, designers usually spend a great deal of time and expend significant effort in choosing appropriate colour combinations. In this article, the importance of colour harmony and its application when extracting colours, rating and generating colour schemes is presented

Image recoloring induced by Palette Color Associations

In this paper we present a non-interactive method for recoloring a destination image according to the color scheme found in a source image. The approach is motivated by trying to invert the working process employed in oil painting, and results are demonstrated by application to several well-known oil paintings. The algorithm uses several color models, but leans most heavily on the Lαβ color space. We first color segment each image bottomup by iteratively merging groups of pixels into connected regions of similar color. During color segmentation, a color “texture” tree is generated and associated to each region. Next, we construct classes of regions by compensating for color duplication and color similarity within the set of averaged color values obtained from regions. We extract a color palette for each image by choosing the colors of canonical region representatives from these classes. Once this palette is constructed for each image, any inverse map from the set of destination palette colors to the set of source palette colors induces a forward map from the classes of regions in the source image to sets of classes of regions in the destination image. For each source class in the range of the inverse map we transfer color from its canonical region representative to each of the associated destination regions. Color transfer occurs at the level of pixels, and uses the color texture trees associated to the regions. Our recoloring method attempts to maintain the destination image’s original value structure. This is accomplished by transferring only the α and β channels from the source. To make our method computationally tractable, we work within an image pyramid, transferring color layer by layer