A study was performed on multiscale model of adaptation, spatial vision and color appearance. The aim of the model is to predict various visual phenomena which simple tristimulus colorimetry can not adequately describ...
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A study was performed on multiscale model of adaptation, spatial vision and color appearance. The aim of the model is to predict various visual phenomena which simple tristimulus colorimetry can not adequately describe. The model simulates luminance, pattern and color processing of the human visual system to accurately predict the color appearance attributes of spectral stimuli in complex surroundings under a wide range of illumination and viewing conditions.
This paper describes a technique for using a simple shading method, such as the Phong lighting model, to approximate the appearance calculated by a more accurate method. The results are then suitable for rapid display...
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A technique for calibrating a charge coupled devices (CCD) camera for direct colorimetric comparison between the captured images of the real environment and synthetic images of the simulated environments is presented....
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A technique for calibrating a charge coupled devices (CCD) camera for direct colorimetric comparison between the captured images of the real environment and synthetic images of the simulated environments is presented. The comparison is used to validate lighting algorithms used for computing synthetic images. The calibration model relating the pixel signal to various physical factors is tested using the CCD camera and an integrating sphere uniform light source.
In this paper we develop a computational model of visual masking based on psychophysical data. The model predicts how the presence of one visual pattern aects the detectability of another. The model allows us to choos...
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The paper presents Act, an object oriented library for projects from specialized 3D graphics applications to simple interactive educational programs. Act meets the needs of both occasional and expert graphicsprogramm...
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The paper presents Act, an object oriented library for projects from specialized 3D graphics applications to simple interactive educational programs. Act meets the needs of both occasional and expert graphicsprogrammers, offering a high level access to the OpenGL library and additional features including object creation, manipulation, and interaction. An interpreted language allows the Act library to be extended easily and dynamically.
In this paper, we discuss the use of computergraphics techniques to model and explain the structures commonly observed in color histograms of images. This includes an accurate simulation of the physical reflection an...
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In this paper, we discuss the use of computergraphics techniques to model and explain the structures commonly observed in color histograms of images. This includes an accurate simulation of the physical reflection and transport behavior of light energy within 3D environments, the precise modeling of an image capturing system, and an interactive visualization module to display color histograms. Based on the fundamental rendering equation that describes light reflection and transport in the 3D world, we classify the color histogram structures of color images, and relate them to various physical components in image formation, including scene illumination, material reflectance properties, and the surface geometry of objects. We further show how these histogram structures can be effected by the artifacts caused by the limitation of image capturing systems. Our results demonstrate that the use of accurate simulation procedures under a precisely controlled computer graphic environment can clearly illustrate the causes of the structures observed, and can provide unique insights and explanations of image formation.
Our goal is to develop physically based lighting models and perceptually based rendering procedures for computergraphics that will produce synthetic images that are visually and measurably indistinguishable from real...
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ISBN:
(纸本)0897918967
Our goal is to develop physically based lighting models and perceptually based rendering procedures for computergraphics that will produce synthetic images that are visually and measurably indistinguishable from real-world images. Fidelity of the physical simulation is of primary concern. Our research framework is subdivided into three sub-sections: the local light reflection model, the energy transport simulation, and the visual display algorithms. The first two subsections are physically based, and the last is perceptually based. We emphasize the comparisons between simulations and actual measurements, the difficulties encountered, and the need to utilize the vast amount of psychophysical research already conducted. Future research directions are enumerated. We hope that results of this research will help establish a more fundamental, scientific approach for future rendering algorithms. This presentation describes a chronology of past research in global illumination and how parts of our new system are currently being developed.
We discuss the theory and practical issues behind creating reflection models to show the difficulty of the problem. We survey the current approaches towards reflection models for computergraphics to show that even fo...
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We discuss the theory and practical issues behind creating reflection models to show the difficulty of the problem. We survey the current approaches towards reflection models for computergraphics to show that even for simple surfaces, the important issues are far from settled. We briefly discuss future directions for research. Finally, we present a case study of a particular type of light reflection that captures some important aspects of appearance for a limited class of materials with subsurface reflection.
作者：
Tomas M?ller[a]Ben Trumbore[b][a]Prosolvia Clarus AB
Chalmers University of Technology Gardaviigen S-41250 Gothenberg Sweden E-mail: [b]Program of Computer Graphics Cornell University Ithaca NY 14853 E-mail:
We present a clean algorithm for determining whether a ray intersects a triangle. The algorithm translates the origin of the ray and then changes the base to yield a vector (t u v)T, wheretis the distance to the plane...
We present a clean algorithm for determining whether a ray intersects a triangle. The algorithm translates the origin of the ray and then changes the base to yield a vector (t u v)T, wheretis the distance to the plane in which the triangle lies and (u,v) represents the coordinates inside the *** advantage of this method is that the plane equation need not be computed on the fly nor be stored, which can amount to significant memory savings for triangle meshes. As we found our method to be comparable in speed to previous methods, we believe it is the fastest ray-triangle intersection routine for triangles that do not have precomputed plane equations.
In spite of the number of efforts made by the computergraphics researchers, till today the computation of view-independent global illumination in an environment containing non-diffusely reflecting objects is a non-re...
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In spite of the number of efforts made by the computergraphics researchers, till today the computation of view-independent global illumination in an environment containing non-diffusely reflecting objects is a non-resolved problem. In general non-deterministic techniques seem to be capable of solving this problem. In this article we propose one such non-deterministic method which will permit such calculation by using a combined technique of higher order function approximation and particle tracing. We have used multi-wavelets as basis functions and have calculated the illumination function approximation coefficients;by exploiting the adjointness between the radiance equation and the potential equation.
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