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1	Comprehensive Digital Archiving Techniques through High-resolution Imaging System with Line Sensor / ラインセンサーを用いた高精細イメージングシステムによる総合的デジタルアーカイブ技術 Wang, Peng 23 March 2022 (has links) 京都大学 / 新制・課程博士 / 博士(工学) / 甲第23881号 / 工博第4968号 / 新制\|\|工\|\|1776(附属図書館) / 京都大学大学院工学研究科機械理工学専攻 / (主査)教授蓮尾昌裕, 教授松原厚, 教授鈴木基史 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM Digital archiving High-resolution Color reproduction 2.5D surface reconstruction Line sensor 500
2	Multispectral Color Reproduction Using DLP / Multispektral färgåtergivning med DLP Nyström, Daniel January 2002 (has links) <p>The color gamut, i.e. the range of reproducible colors, is in most conventional display systems not sufficient for accurate color reproduction of highly saturated colors. Any conventional three-primary display suffers from a color gamut limited within the triangle spanned by the primary colors. Even by using purer primaries, enlarging the triangle, there will still be a problem to cover all the perceivable colors. By using a system with more than three primary colors, in printing denoted Hi-Fi color, the gamut will be expanded into a polygon, yielding a larger gamut and better color reproduction. </p><p><i>Digital Light Processing (DLP)</i> is a projection technology developed by Texas Instrument. It uses a chip with an array of thousands of individually controllable micromirrors, each representing a single pixel in the projected image. A lamp illuminates the micromirrors, and by controlling the amount of time each mirror reflect the light, using pulse width modulation, the projected image is created. Color reproduction is achieved by letting the light pass through color filters, corresponding to the three primaries, mounted in a filter wheel. </p><p>In this diploma work, the DLP projector InFocus<sup>®</sup> LP™350 has been evaluated, using the Photo Research<sup>®</sup> PR<sup>®</sup>-705 Spectroradiometer. The colorimetric performance of the projector is found to be surprisingly poor, with a color gamut noticeably smaller then that of a CRT monitor using standardized phosphors. This is due to the broad banded filters used, yielding increased brightness at the expense of the pureness of the primaries. </p><p>With the intention of evaluating the potential for the DLP technology in multi- primary systems, color filters are selected for additional primary colors. The filters are selected from a set of commercially available filters, the Kodak Wratten filters for science and technology. Used as performance criteria for filter selection is the volume of the gamut in the CIE 1976 (Luv) uniform color space. </p><p>The selected filters are measured and evaluated in combination with the projector, verifying the theoretical results from the filter selection process. Colorimetric performance of the system is greatly improved, yielding an expansion of the color gamut in CIE 1976 (Luv) color space by 79%, relative the original three-primary system. These results indicate the potential for DLP in multiprimary display systems, with the capacity to greatly expand the color gamut, by using carefully selected filters for additional primary colors.</p> Datorteknik Digital Light Processing multispectral color reproduction Hi-Fi color multiprimary display filter selection Datorteknik Computer engineering Datorteknik
3	Multispectral Color Reproduction Using DLP / Multispektral färgåtergivning med DLP Nyström, Daniel January 2002 (has links) The color gamut, i.e. the range of reproducible colors, is in most conventional display systems not sufficient for accurate color reproduction of highly saturated colors. Any conventional three-primary display suffers from a color gamut limited within the triangle spanned by the primary colors. Even by using purer primaries, enlarging the triangle, there will still be a problem to cover all the perceivable colors. By using a system with more than three primary colors, in printing denoted Hi-Fi color, the gamut will be expanded into a polygon, yielding a larger gamut and better color reproduction. Digital Light Processing (DLP) is a projection technology developed by Texas Instrument. It uses a chip with an array of thousands of individually controllable micromirrors, each representing a single pixel in the projected image. A lamp illuminates the micromirrors, and by controlling the amount of time each mirror reflect the light, using pulse width modulation, the projected image is created. Color reproduction is achieved by letting the light pass through color filters, corresponding to the three primaries, mounted in a filter wheel. In this diploma work, the DLP projector InFocus® LP™350 has been evaluated, using the Photo Research® PR®-705 Spectroradiometer. The colorimetric performance of the projector is found to be surprisingly poor, with a color gamut noticeably smaller then that of a CRT monitor using standardized phosphors. This is due to the broad banded filters used, yielding increased brightness at the expense of the pureness of the primaries. With the intention of evaluating the potential for the DLP technology in multi- primary systems, color filters are selected for additional primary colors. The filters are selected from a set of commercially available filters, the Kodak Wratten filters for science and technology. Used as performance criteria for filter selection is the volume of the gamut in the CIE 1976 (Luv) uniform color space. The selected filters are measured and evaluated in combination with the projector, verifying the theoretical results from the filter selection process. Colorimetric performance of the system is greatly improved, yielding an expansion of the color gamut in CIE 1976 (Luv) color space by 79%, relative the original three-primary system. These results indicate the potential for DLP in multiprimary display systems, with the capacity to greatly expand the color gamut, by using carefully selected filters for additional primary colors. Datorteknik Digital Light Processing multispectral color reproduction Hi-Fi color multiprimary display filter selection Datorteknik Computer Engineering Datorteknik
4	Applied color processing Zhang, Heng 29 November 2011 (has links) The quality of a digital image pipeline relies greatly on its color reproduction which should at a minimum handle the color constancy, and the final judgment of the excellence of the pipeline is made through subjective observations by humans. This dissertation addresses a few topics surrounding the color processing of digital image pipelines from a practical point of view. Color processing fundamentals will be discussed in the beginning to form a background understanding for the topics that follow.A memory color assisted illuminant estimation algorithm is then introduced after a review of memory colors and some modeling techniques. Spectral sensitivity of the camera is required by many color constancy algorithms but such data is often not readily available. To tackle this problem, an alternative method to the spectral characterization for color constancy parameter calibration is proposed. Hue control in color reproduction can be of great importance especially when memory colors are concerned. A hue constrained matrix optimization algorithm is introduced to address this issue, followed by a psychophysical study to systematically arrive at a recommendation for the optimized preferred color reproduction. At the end, a color constancy algorithm for high dynamic range scenes observing multiple illuminants is proposed. / Graduation date: 2012 color constancy illuminant estimation preferred color reproduction color correction matrix optimization simultaneous color constancy Image processing -- Mathematical models
5	A Physically Based Pipeline for Real-Time Simulation and Rendering of Realistic Fire and Smoke / En fysiskt baserad rörledning för realtidssimulering och rendering av realistisk eld och rök He, Yiyang January 2018 (has links) With the rapidly growing computational power of modern computers, physically based rendering has found its way into real world applications. Real-time simulations and renderings of fire and smoke had become one major research interest in modern video game industry, and will continue being one important research direction in computer graphics. To visually recreate realistic dynamic fire and smoke is a complicated problem. Furthermore, to solve the problem requires knowledge from various areas, ranged from computer graphics and image processing to computational physics and chemistry. Even though most of the areas are well-studied separately, when combined, new challenges will emerge. This thesis focuses on three aspects of the problem, dynamic, real-time and realism, to propose a solution in form of a GPGPU pipeline, along with its implementation. Three main areas with application in the problem are discussed in detail: fluid simulation, volumetric radiance estimation and volumetric rendering. The weights are laid upon the first two areas. The results are evaluated around the three aspects, with graphical demonstrations and performance measurements. Uniform grids are used with Finite Difference (FD) discretization scheme to simplify the computation. FD schemes are easy to implement in parallel, especially with ComputeShader, which is well supported in Unity engine. The whole implementation can easily be integrated into any real-world applications in Unity or other game engines that support DirectX 11 or higher. Visualization Physically Based Pipeline Real-Time Dynamic Simulation Combustion Fire Explosion Smoke Thick Smoke Computer Graphics PDE Numerical Methods Grid Based Navier-Stokes Equation Imcompressible Fluid Radiative Transfer Equation RTE Volumetric Illumination Volumetric Rendering Volumetric Global Illumination Distant Light Source Volumetric Global Shadow Local Shadow Approximation Black-body Radiation Poisson Solver Spectroscopy Fire Color Color Reproduction Tone Mapping Color Temperature Color Matching Function Tristimulus CIE Standard Observer Color Space XYZ RGB GPU GPGPU ComputeShader DirectX 12 Unity C# Computer Sciences Datavetenskap (datalogi)

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