The quality of several colour image difference metrics, pixelwise CIELAB DEab, S-CIELAB, iCAM, Structural Similarity Index, Universal Image Quality and the hue-angle algorithm, have been investigated. These results were compared with the results from a psychophysical experiment in which the perceptual image difference was evaluated. Six original images were reproduced using six different colour...

The pellicle or seed coat of almond kernels is subject to darkening during long-term storage and may affect the marketability of the stored product. Environmental conditions during storage and genetic factors both affect the extent of darkening during the storage period. The degree of pellicle color change of five distinct almond accessions was examined during long-term storage at 2, 22 and 32 ...

Anthocyanin pigments readily degrade during processing and storage of foodstuffs, which can have a dramatic impact on color quality and may also affect nutritional properties. Total anthocyanin pigment content and indices for polymeric color and browning are easily measured with simple spectrophotometric methods. Once individual pigments are identified, their changes can be monitored by high-pe...

Color constancy in color image segmentation is an important research issue. In this paper we develop a framework, based on the Dichromatic Re ection Model for asserting the color highlight and shading invariance, and based on a Markov Random Field approach for segmentation. A given RGB image is transformed into a R'G'B' space to remove any highlight components, and only the vector-angle compone...

A new method of color image segmentation is proposed in this paper. It’s based on K-means algorithm in HSI space and has the advantage over those based on the RGB space. Both the hue and the intensity components are fully utilized. In the process of hue clustering, the special cyclic property of the hue component is taken into consideration. The paper gives the definition of the distance and th...

Three methods for summarising the characteristics of colour images are presented. They all rely on the ability to represent colours in terms of a 3D-polar coordinate system having independent brightness and saturation coordinates. The methods discussed are: hue statistics and saturation-weighted hue statistics, saturation-weighted hue histograms, and colour statistics histograms. The latter are...

Primate visual systems support an elaborate specialization for processing color information. Concentrating on the hue component, we observe that, contrary to Mondrian-like assumptions, hue varies in a smooth manner for ecologically important natural imagery. To represent these smooth variations, and to support those information processing tasks that utilize hue, a piecewise smooth hue field is ...

We present a systematic algorithm capable of searching for optimal colors for any lightness L* (between 0 and 100), any illuminant (D65, F2, F7, F11, etc.), and any light source reported by CIE. Color solids are graphed in some color spaces (CIELAB, SVF, DIN99d, and CIECAM02) by horizontal (constant lightness) and transversal (constant hue angle) sections. Color solids plotted in DIN99d and CIE...

The demand function for vaccines against typhoid fever was estimated using stated preference data collected from a random sample of 1065 households in Hue, Vietnam, in 2002. These are the first estimates of private willingness-to-pay (WTP) and demand functions for typhoid vaccines in a developing country. Mean respondent WTP for a single typhoid fever vaccine ranged from USD 2.30 to USD 4.80. M...