A common problem in the field of color printing is closed loop color calibration, a process which generally requires a spectrometer. Light Emitting Diodes (LED) sensors are inexpensive and effective for measuring the net reflectance of certain frequencies of light. Sensor measurement of LED reflectance can be used to estimate spectral reflectance or color value (measured in CIELAB or CIEXYZ col...

The angle resolved reflectance factor of matte samples is measured with a goniophotometer and simulated using radiative transfer theory. Both measurements and simulations display the same characteristic dependence of the reflectance factor on the observation angle. The angle resolved reflectance spectra are translated to CIELAB col...

We apply a general form of affine transformation model to compensate illumination variations in a series of multispectral images of a static scene and compare it to a particular affine and a diagonal transformation models. These models operate in the original multispectral space or in a lower-dimensional space obtained by Singular Value Decomposition (SVD) of the set of images. We use a system ...

Color is one of the most important low-level features used in image analysis and retrieval. In this paper we introduce an algorithm for extracting compact color feature in the CIELAB color space. Our method is based on an ant colony clustering algorithm, which helps us develop a perceptually based image similarity metric. We propose a dominant color and area percentage model, which provides a v...

Introduction: The color stability of composite resins is a fundamental factor in their clinical behavior. Objective: To evaluate the color stability of composite resins of different colors exposed to a colabased soft drink after different storage periods. Additionally, three methacrylate-based materials and one silorane-based material were evaluated. Material and methods: Specimens of three met...

Karamucki T., Gardzielewska J., Rybarczyk A., Jakubowska M., Natalczyk-Szymkowska W. (2011): Usefulness of selected methods of colour change measurement for pork quality assessment. Czech J. Food Sci., 29: 212–218. A few selected methods of the meat colour change determination were compared with regard to their usefulness in the assessment of the quality of minced pork. The study was carried ou...

Color is one of the most effective visual variables since it can be combined with other mappings and encode information without using any additional space on the display. An important example where expressing additional visual dimensions is direly needed is the analysis of high-dimensional data. The property of perceptual linearity is desirable in this application, because the user intuitively ...

Theoretical analyses of spectral reflectances of natural surfaces suggest that their perceived colors can be well reproduced by approximations comprising combinations of three or four spectral basis functions. The aim of the present work was to assess psychophysically the number of basis functions necessary to reproduce entire natural outdoor scenes. Hyperspectral images of 20 such scenes were ...