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Abstract

Humans recognize objects visually on the basis of material composition as well as shape. To acquire a certain level of photorealism, it is necessary to analyze, how the materials scatter the incident light. The key quantity for expressing the directional optical effect of materials on the incident radiance is the bidirectional reflectance distribution function (BRDF). Our work is devoted to the BRDF measurements, in order to render the synthetic images, mostly of the metallic paints. We measured the spectral reflectance off multiple paint samples then used the measured data to fit the analytical BRDF model, in order to acquire its parameters. In this paper we describe the methodology of the image synthesis from measured data. Materials such as the metallic paints exhibit a sparkling effect caused by the metallic particles scattered within the paint volume. Our analysis of sparkling effect is based on the processing of the multiple photographs. Results of analysis and the measurements were incorporated into the rendering process of car paint

Abstract

Measurement of the appearance of an object consists of a group of measurements to characterize the color and surface finish of the object. This group of measurements involves the spectral energy distribution of propagated light measured in terms of reflectance and transmittance, and the spatial energy distribution of that light measured in terms of the bidirectional reflectance distribution function (BRDF). In this article we present the virtual gonio-spectrophotometer, a device that measures flux (power) as a function of illumination and observation. Virtual gonio-spectrophotometer measurements allow the determination of the scattering profile of specimens that can be used to verify the physical characteristics of the computer model used to simulate the scattering profile. Among the characteristics that we verify is the energy conservation of the computer model. A virtual gonio-spectrophotometer is utilized to find the correspondence between industrial measurements obtained from gloss meters and the parameters of a computer reflectance model.

Abstract

The field of predictive rendering concerns itself with those methods of image synthesis which yield results that do not only look real, but are also radiometrically correct renditions of nature, i.e., which are accurate predictions of what a real scene would look like under given lighting conditions. A real coating consists of pigments, effect pigments, clear lacquer and glaze. A novel and unique combination of real parameters that are commonly measured in the industry and a theoretical reflectance model consisting of measurable parameters is required. Here, the authors design perception parameters and put them into well known surface reflection functions such as He and Torrance. The original contributions are the study of the sub-surface scattering of real paint and the prediction of its appearance in rendered images by the proposed model of light reflection beneath the paint surface.

References [1] Dougherty, E.R., Astola J. (1993). Mathematical Non-Linear Image Processing, Kluwer Academic Publishers, London [2] Haindl, M., Filip, J. (2013). Visual Texture. Accurate Material Appearance Measurement, Representation and Modeling, Springer [3] Julesz, B. (1981). Textons, the elements of texture perception and their interaction, Nature 290, 91-97 [4] Manjunath, B.S., Ma, W.Y. (1996). Texture features for browsing and retrieval of image data, IEEE Transactions on Pattern Analysis and Machine Intelligence (PAMI) 18(8), 837-42 [5] Petrou, M., Sevilla

of the lung function results of the two groups was appropriate and meaningful. All the infants were electively intubated at birth because of their immaturity, according to the standard policy of the NICU. Infants who are born very prematurely can require on going respi- ratory support because of factors other than se- vere lung disease; these include poor respiratory J. Perinat. Med. 27 (1999) muscle function and respiratory control. The in- fants were diagnosed as having RDS or not, by the clinician in charge because of their chest ra- diograph appearance

. 311, Nr. 1, 2011. 10. „BYK-Gardner GmbH, Orange Peel and DOI Meters“, https:// www.byk.com/en/instruments/products/appearance- measurement/orange-peel-doi-meter.html, accessed on 2014- 02-13. 11. M. Ziebarth, M. Vogelbacher, S. Olawsky und J. Beyerer, „Ob- taining 2d surface characteristics from specular surfaces“, in German Conference on Pattern Recognition, 2014. 12. D. Pérard, „Automated visual inspection of specular surfaces with structured-lightning reflection techniques“, Dissertation, University of Karlsruhe, 2000. 13. S. Werling, M. Mai, M. Heizmann und J

5 20. Whereas numerous studies exist on the electron attachment to the N2O monomer (see for in- stance the recent paper [10] and references given therein) and on the elec- tron impact ionization of gaseous N2O (see for instance all the appearance measurements listed in [11]), the number of previous studies concerning the interaction of free electrons with N2O clusters is very limited. On the one hand, Linn and Ng [12] measured the ionization threshold of the (N2O)12 dimer ion in a photoionization mass spectrometric (PIMS) study to lie at 12.356 0.02 eV and on the

240 240 2 40 240 2 40 240 240 For leading review on ionization potentials of transient molecules see: R.D.Levin, S.G Lias. "Ionlzatlon potential and appearance measurements, 1971-1981", Natl. Stand. Ref. Data. Ser., Natl. Bur. Stand. (U.S.), No 71 (1982). * Physical properties of carbenes and carbene analogues 277 Molecule and und state Vrm 1' Table 4. The excited states energies of,three-atom carbenes and their analogues References Excited state Excitation energy term from the ground state, eV L 3 4 :CH2, 3B1 :CF2, 1 A1 :CHI?, 'A' :CC12, 1 A

International standards and regulations The following section is reprinted from the application note: “Test methods for color measurement,” with kind permission from HunterLab, www.hunterlab.com. More information on color measurement methods and regulations can be found at http://www.hunterlab.com/application-notes.html The world governing body for color and appearance measurement is the CIE, Commission Internationale de l’Eclairage, or the International Commission on Illumination. They can be found online at www.cie.co.at. Their fundamental pub- lication is

) plane. In fact, they often occur for measurements of any two neutrino and/or antineutrino appearance probabilities, even if they are not at the same L and Eν [319], as long as each measurement is made at fixed L and E. Making a third appearance measurement resolves the (δ, θ13) ambiguity and reduces the regions where the remaining degeneracies occur to lines in (δ, θ13) space. Making a fourth appearance measurement reduces the occurence of these degeneracies to isolated points in the (δ, θ13) plane. A fifth measurement then in principle removes all remaining