The goal of the work reported in this dissertation is to develop methods for the acquisition and reproduction of high quality digital colour images. To reach this goal it is necessary to understand and control the way in which the different devices involved in the entire colour imaging chain treat colours. Therefore we addressed the problem of colorimetric characterisation of scanners and print...

Colour parameters of European beech were measured using CIELab system. 103 logs from 87 trees in 9 sites were cut into boards to study the variations of wood colour parameters. Both site and tree effect on colour were observed. Patterns of red heartwood occurrence were defined. When excepting red heartwood there was still a highly significant effect of site and tree; differences remained after ...

Two methods for colorimetric characterization of color scanner are proposed based on the measures of perceptual color difference error. The first method is used to minimize the total color differences between the actual and predicted color samples. The second one, which is a generalization of the existing cubic-root preprocessing technique, derives the mapping between the p’th root of scanner r...

Human skin colour measurements from four ethnic groups including 188 subjects were accumulated. Five to ten locations of each subject were measured by using two different instruments, a tele-spectroradiometer and a spectrophotometer. Three repeated measurements were accumulated for each location. Repeatability of the measurements at different locations from different ethnicities was examined us...

This work describes a first step towards the creation of an engineering model for the perception of color difference as a function of size. Our approach is to non-uniformly rescale CIELAB using data from crowdsourced experiments, such as those run on Amazon Mechanical Turk. In such experiments, the inevitable variations in viewing conditions reflect the environment many applications must run in...

This paper studies the restoration of color-quantized images. Restoration of color-quantized images is rarely addressed in literature, and direct applications of existing restoration techniques are generally inadequate to deal with this problem. In this paper, we propose a restoration algorithm for restoring color-quantized images. This algorithm makes good use of the available color palette to...

The effect of two anti-fungal treatments (metrafenone and boscalid + kresoxim-methyl) on the color and phenolic profile of Tempranillo and Graciano red wines has been studied. To evaluate possible modifications in color and phenolic composition of wines, control and wines elaborated with treated grapes under good agricultural practices were analyzed. Color was assessed by Glories and CIELab par...

This paper addresses the problem of interpolating missing color components at the output of a Bayer color filter array (CFA), a process known as demosaicking. A luma-chroma demultiplexing algorithm is presented in detail, using a least-squares design methodology for the required bandpass filters. A systematic study of objective demosaicking performance and system complexity is carried out, and ...

Color appearance models provide a powerful tool for achieving a viewing condition independent color representation. However, current color appearance models such as CIECAM97s and CAM97s2 are more complex than previous CIE device independent color spaces, such as CIELAB and CIELUV. Therefore it is important to understand how to correctly measure and set the input parameters. This paper provides ...

Human face detection plays an important role in many applications such as face recognition , human computer interface, biometrics, area of energy conservation, video surveillance and face image database management. The selection of accurate color model is the first need of the face detection. In this paper, a study on the various color models for face detection i.e. RGB, YCbCr, HSV and CIELAB a...