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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, February 2003., "January 2003.", Includes bibliographical references (p. 57-59)., by Jingyi Yu., S.M.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003., Includes bibliographical references (leaves 74-80)., by Wai Kit Addy Ngan., S.M.

Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000., Includes bibliographical references (leaves 54-55)., by Jason C. Yang., M.Eng.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001., Includes bibliographical references (p. 79-81)., by Wojciech Matusik., S.M.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003., "September 2003.", Includes bibliographical references (leaves 112-115)., I present a data-driven model for isotropic bidirectional reflectance distribution functions (BRDFs) based on acquired reflectance data. Instead of using analytic reflectance models, each BRDF is represented as a dense set of measurements. This representation allows interpolation and extrapolation in the space of acquired BRDFs to create new BRDFs. Each acquired BRDF is treated as a single high-dimensional vector taken from the space of all possible BRDFs. Both linear (subspace) and non-linear (manifold) dimensionality reduction tools are applied in an effort to discover a lower-dimensional representation that characterizes the acquired BRDFs. To complete the model, users are provided with the means for defining perceptually meaningful parametrizations that allow them to navigate in the reduced-dimension BRDF space. On the low-dimensional manifold, movement along these directions produces novel, but valid, BRDFs. By analyzing a large collection of reflectance data, I also derive two novel reflectance sampling procedures that require fewer total measurements than standard uniform sampling approaches. Using densely sampled measurements the general surface reflectance function is analyzed to determine the local signal variation at each point in the function's domain. Wavelet analysis is used to derive a common basis for all of the acquired reflectance functions, as well as a non-uniform sampling pattern that corresponds to all non-zero wavelet coefficients. Second, I show that the reflectance of an arbitrary material can be represented as a linear combination of the surface reflectance functions. Furthermore, this analysis specifies a reduced set of sampling points that permits the robust estimation of the coefficients of this linear combination., (cont.) These procedures dramatically shorten the acquisition time for isotropic reflectance measurements., by Wojciech Matusik., Ph.D.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003., Includes bibliographical references (p. 81-82)., by Matthew M. Everett., S.M.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003., Includes bibliographical references (leaves 74-80)., by Wai Kit Addy Ngan., S.M.

Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000., Includes bibliographical references (leaf 34)., by Charles B. Lee., S.B.and M.Eng.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003., Includes bibliographical references (leaves 74-80)., by Wai Kit Addy Ngan., S.M.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003., "September 2003.", Includes bibliographical references (p. 169-180)., This thesis investigates the creation, representation, and manipulation of volumetric geometry suitable for computer graphics applications. In order to capture and reproduce the appearance and behavior of many objects, it is necessary to model the internal structures and materials, and how they change over time. However, producing real-world effects with standard surface modeling techniques can be extremely challenging. My key contribution is a concise procedural approach for authoring layered, solid models. Using a simple scripting language, a complete volumetric representation of an object, including its internal structure, can be created from one or more input surfaces, such as scanned polygonal meshes, CAD models or implicit surfaces. Furthermore, the resulting model can be easily modified using sculpting and simulation tools, such as the Finite Element Method or particle systems, which are embedded as operators in the language. Simulation is treated as a modeling tool rather than merely a device for animation, which provides a novel level of abstraction for interacting with simulation environments. I present an implementation of the language using a flexible tetrahedral representation, which I chose because of its advantages for simulation tasks. The language and implementation are demonstrated on a variety of complex examples that were inspired by real-world objects., by Barbara M. Cutler., Ph.D.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001., Includes bibliographical references (p. 79-81)., by Wojciech Matusik., S.M.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003., Includes bibliographical references (p. 119-120)., by Matthew R. Peters., S.M.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003., Includes bibliographical references (p. 81-82)., by Matthew M. Everett., S.M.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003., "September 2003.", Includes bibliographical references (p. 169-180)., This thesis investigates the creation, representation, and manipulation of volumetric geometry suitable for computer graphics applications. In order to capture and reproduce the appearance and behavior of many objects, it is necessary to model the internal structures and materials, and how they change over time. However, producing real-world effects with standard surface modeling techniques can be extremely challenging. My key contribution is a concise procedural approach for authoring layered, solid models. Using a simple scripting language, a complete volumetric representation of an object, including its internal structure, can be created from one or more input surfaces, such as scanned polygonal meshes, CAD models or implicit surfaces. Furthermore, the resulting model can be easily modified using sculpting and simulation tools, such as the Finite Element Method or particle systems, which are embedded as operators in the language. Simulation is treated as a modeling tool rather than merely a device for animation, which provides a novel level of abstraction for interacting with simulation environments. I present an implementation of the language using a flexible tetrahedral representation, which I chose because of its advantages for simulation tasks. The language and implementation are demonstrated on a variety of complex examples that were inspired by real-world objects., by Barbara M. Cutler., Ph.D.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003., Includes bibliographical references (p. 119-120)., by Matthew R. Peters., S.M.

Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000., Includes bibliographical references (leaves 54-55)., by Jason C. Yang., M.Eng.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001., Includes bibliographical references (p. 79-81)., by Wojciech Matusik., S.M.

Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000., Includes bibliographical references (leaf 34)., by Charles B. Lee., S.B.and M.Eng.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, February 2001., Includes bibliographical references (leaves 77-79)., by Aaron Isaksen., S.M.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003., Includes bibliographical references (p. 81-82)., by Matthew M. Everett., S.M.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003., "September 2003.", Includes bibliographical references (p. 169-180)., This thesis investigates the creation, representation, and manipulation of volumetric geometry suitable for computer graphics applications. In order to capture and reproduce the appearance and behavior of many objects, it is necessary to model the internal structures and materials, and how they change over time. However, producing real-world effects with standard surface modeling techniques can be extremely challenging. My key contribution is a concise procedural approach for authoring layered, solid models. Using a simple scripting language, a complete volumetric representation of an object, including its internal structure, can be created from one or more input surfaces, such as scanned polygonal meshes, CAD models or implicit surfaces. Furthermore, the resulting model can be easily modified using sculpting and simulation tools, such as the Finite Element Method or particle systems, which are embedded as operators in the language. Simulation is treated as a modeling tool rather than merely a device for animation, which provides a novel level of abstraction for interacting with simulation environments. I present an implementation of the language using a flexible tetrahedral representation, which I chose because of its advantages for simulation tasks. The language and implementation are demonstrated on a variety of complex examples that were inspired by real-world objects., by Barbara M. Cutler., Ph.D.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003., Includes bibliographical references (leaves 74-80)., by Wai Kit Addy Ngan., S.M.

Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000., Includes bibliographical references (leaf 34)., by Charles B. Lee., S.B.and M.Eng.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003., Includes bibliographical references (p. 119-120)., by Matthew R. Peters., S.M.

Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000., Includes bibliographical references (leaves 54-55)., by Jason C. Yang., M.Eng.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003., Includes bibliographical references (leaves 136-139)., Animations of three-dimensional computer graphics are becoming an increasingly prevalent medium for communication. There are many sources of 3D animations including physical simulations, scientific visualizations, and classic key-frame animations generated by an artist. There are even computer vision systems available today that are capable of capturing 3D time-varying geometric models. In this research, we develop a new representation for an important class of 3D animations, specifically time-varying manifolds. We call this representation a "Geometry Video." At present, a viewer of a 3D animation must either have a similar simulation or animation infrastructure to the animation's producer, or the producer must create a video from a predefined set of viewpoints. Geometry videos provide the ability to encode and transmit a time-varying mesh in a generic, source-independent, and view-independent format. Geometry videos are created by constructing a global two-dimensional parametrization of a manifold over a rectangular domain. Time sequences of such parametrizations are particularly well-suited to compression using methods akin to video compression. This dissertation develops the techniques necessary to encode and compress arbitrary 3D manifold animations. A system is presented for converting animations into geometry videos as well as compressing and decompressing such representations. We also discusses the problems, design-parameters, and trade-offs associated with building such a system., by Héctor Manuel Briceño Pulido., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2003., "September 2003.", Includes bibliographical references (leaves 112-115)., I present a data-driven model for isotropic bidirectional reflectance distribution functions (BRDFs) based on acquired reflectance data. Instead of using analytic reflectance models, each BRDF is represented as a dense set of measurements. This representation allows interpolation and extrapolation in the space of acquired BRDFs to create new BRDFs. Each acquired BRDF is treated as a single high-dimensional vector taken from the space of all possible BRDFs. Both linear (subspace) and non-linear (manifold) dimensionality reduction tools are applied in an effort to discover a lower-dimensional representation that characterizes the acquired BRDFs. To complete the model, users are provided with the means for defining perceptually meaningful parametrizations that allow them to navigate in the reduced-dimension BRDF space. On the low-dimensional manifold, movement along these directions produces novel, but valid, BRDFs. By analyzing a large collection of reflectance data, I also derive two novel reflectance sampling procedures that require fewer total measurements than standard uniform sampling approaches. Using densely sampled measurements the general surface reflectance function is analyzed to determine the local signal variation at each point in the function's domain. Wavelet analysis is used to derive a common basis for all of the acquired reflectance functions, as well as a non-uniform sampling pattern that corresponds to all non-zero wavelet coefficients. Second, I show that the reflectance of an arbitrary material can be represented as a linear combination of the surface reflectance functions. Furthermore, this analysis specifies a reduced set of sampling points that permits the robust estimation of the coefficients of this linear combination., (cont.) These procedures dramatically shorten the acquisition time for isotropic reflectance measurements., by Wojciech Matusik., Ph.D.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, February 2003., "January 2003.", Includes bibliographical references (p. 57-59)., by Jingyi Yu., S.M.

Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000., Includes bibliographical references (leaves 54-55)., by Jason C. Yang., M.Eng.

Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000., Includes bibliographical references (leaf 34)., by Charles B. Lee., S.B.and M.Eng.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2001., Includes bibliographical references (p. 92-95)., I present a novel drawing system for composing and rendering perspective scenes. The proposed approach uses a projective two-dimensional representation for primitives rather than a conventional three-dimensional description. This representation is based on points that lie on the surface of a unit sphere centered at the viewpoint. It allows drawings to be composed with the same ease as traditional illustrations, while providing many of the advantages of a three-dimensional model. I describe a range of user-interface tools and interaction techniques that give the drawing system its three-dimensional-like capabilities. The system provides vanishing point guides and perspective grids to aid in drawing freehand strokes and composing perspective scenes. The system also has tools for intuitive navigation of a virtual camera, as well as methods for manipulating drawn primitives so that they appear to undergo three-dimensional translations and rotations. The new representation also supports automatic shading of primitives using either realistic or non-photorealistic styles. My system supports drawing and shading of extrusion surfaces with automatic hidden surface removal and emphasized silhouettes. Casting shadows from an infinite light source is also possible with minimal user intervention. I describe a method for aligning a sketch drawn outside the system using its vanishing points, allowing the integration of computer sketching and freehand sketching on paper in an iterative manner. Photographs and scanned drawings are applied to drawing primitives using conventional texture-mapping techniques, thereby enriching drawings and providing another way of incorporating hand-drawn images. I demonstrate the system with a variety of drawings., by Osama S. Tolba., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005., Includes bibliographical references (leaves 145-149)., I present a General Linear Camera (GLC) model that unifies many previous camera models into a single representation. The GLC model describes all perspective (pinhole), orthographic, and many multiperspective (including pushbroom and two-slit) cameras, as well as epipolar plane images. It also includes three new and previously unexplored multiperspective linear cameras. The GLC model is general and linear in the sense that, given any vector space where rays are represented as points, it describes all 2D affine subspaces (planes) formed by the affine combination of 3 rays. I also present theories of projection and collineation for GLCs and use these theories to explain various multiperspective distortions. Given an arbitrary multiperspective imaging system that captures smoothly varying set of rays, I show how to map the rays onto a 2D ray manifold embedded into a 4D linear vector space. The GLC model can then be use to analyze the tangent planes on this manifold. Geometric structures associated with the local GLC model of each tangent plane provide an intuitive physical interpretation of the imaging system, and they are closely related to the caustics of reflected rays. These geometric structures are characteristic of only 4 of the 8 GLC types. I also prove that the local GLC type at each tangent plane is invariant to the choice of parametrization, and, thus, an intrinsic property of the reflecting surface. Using GLCs to analyze the caustics of reflection extends the previous Jacobian-based approaches, which consider only a pinhole model at each infinitesimal region about each surface point. Finally, I demonstrate how to use the GLC model in computer vision, computer graphics, and optical design applications. In particular, I show how to use GLCs for modelling and rendering multiperspective images and characterizing real multiperspective imaging systems such as catadioptric mirrors., by Jingyi Yu., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005., Includes bibliographical references (leaves 145-149)., I present a General Linear Camera (GLC) model that unifies many previous camera models into a single representation. The GLC model describes all perspective (pinhole), orthographic, and many multiperspective (including pushbroom and two-slit) cameras, as well as epipolar plane images. It also includes three new and previously unexplored multiperspective linear cameras. The GLC model is general and linear in the sense that, given any vector space where rays are represented as points, it describes all 2D affine subspaces (planes) formed by the affine combination of 3 rays. I also present theories of projection and collineation for GLCs and use these theories to explain various multiperspective distortions. Given an arbitrary multiperspective imaging system that captures smoothly varying set of rays, I show how to map the rays onto a 2D ray manifold embedded into a 4D linear vector space. The GLC model can then be use to analyze the tangent planes on this manifold. Geometric structures associated with the local GLC model of each tangent plane provide an intuitive physical interpretation of the imaging system, and they are closely related to the caustics of reflected rays. These geometric structures are characteristic of only 4 of the 8 GLC types. I also prove that the local GLC type at each tangent plane is invariant to the choice of parametrization, and, thus, an intrinsic property of the reflecting surface. Using GLCs to analyze the caustics of reflection extends the previous Jacobian-based approaches, which consider only a pinhole model at each infinitesimal region about each surface point. Finally, I demonstrate how to use the GLC model in computer vision, computer graphics, and optical design applications. In particular, I show how to use GLCs for modelling and rendering multiperspective images and characterizing real multiperspective imaging systems such as catadioptric mirrors., by Jingyi Yu., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005., Includes bibliographical references (leaves 145-149)., I present a General Linear Camera (GLC) model that unifies many previous camera models into a single representation. The GLC model describes all perspective (pinhole), orthographic, and many multiperspective (including pushbroom and two-slit) cameras, as well as epipolar plane images. It also includes three new and previously unexplored multiperspective linear cameras. The GLC model is general and linear in the sense that, given any vector space where rays are represented as points, it describes all 2D affine subspaces (planes) formed by the affine combination of 3 rays. I also present theories of projection and collineation for GLCs and use these theories to explain various multiperspective distortions. Given an arbitrary multiperspective imaging system that captures smoothly varying set of rays, I show how to map the rays onto a 2D ray manifold embedded into a 4D linear vector space. The GLC model can then be use to analyze the tangent planes on this manifold. Geometric structures associated with the local GLC model of each tangent plane provide an intuitive physical interpretation of the imaging system, and they are closely related to the caustics of reflected rays. These geometric structures are characteristic of only 4 of the 8 GLC types. I also prove that the local GLC type at each tangent plane is invariant to the choice of parametrization, and, thus, an intrinsic property of the reflecting surface. Using GLCs to analyze the caustics of reflection extends the previous Jacobian-based approaches, which consider only a pinhole model at each infinitesimal region about each surface point. Finally, I demonstrate how to use the GLC model in computer vision, computer graphics, and optical design applications. In particular, I show how to use GLCs for modelling and rendering multiperspective images and characterizing real multiperspective imaging systems such as catadioptric mirrors., by Jingyi Yu., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002., Includes bibliographical references (p. 157-163)., Computer graphics researchers recently have turned to image-based rendering to achieve the goal of photorealistic graphics. Instead of constructing a scene with millions of polygons, the scene is represented by a collection of photographs along with a greatly simplified geometric model. This simple representation allows traditional light transport simulations to be replaced with basic image-processing routines that combine multiple images together to produce never-before-seen images from new vantage points. This thesis presents a new image-based rendering algorithm called unstructured lumigraph rendering (ULR). ULR is an image-based rendering algorithm that is specifically designed to work with unstructured (i.e., irregularly arranged) collections of images. The algorithm is unique in that it is capable of using any amount of geometric or image information that is available about a scene. Specifically, the research in this thesis makes the following contributions: * An enumeration of image-based rendering properties that an ideal algorithm should attempt to satisfy. An algorithm that satisfies these properties should work as well as possible with any configuration of input images or geometric knowledge. * An optimal formulation of the basic image-based rendering problem, the solution to which is designed to satisfy the aforementioned properties. * The unstructured lumigraph rendering algorithm, which is an efficient approximation to the optimal image-based rendering solution. * A non-metric ULR algorithm, which generalizes the basic ULR algorithm to work with uncalibrated images. * A time-dependent ULR algorithm, which generalizes the basic ULR algorithm to work with time-dependent data., by Christopher James Buehler., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005., Includes bibliographical references (p. 153-158)., I present the design and analysis of a two-dimensional camera array for virtual studio applications. It is possible to substitute conventional cameras and motion control devices with a real-time, light field camera array. I discuss a variety of camera architectures and describe a prototype system based on the "finite-viewpoints" design that allows multiple viewers to navigate virtual cameras in a dynamically changing light field captured in real time. The light field camera consists of 64 commodity video cameras connected to off-the-shelf computers. I employ a distributed rendering algorithm that overcomes the data bandwidth problems inherent in capturing light fields by selectively transmitting only those portions of the video streams that contribute to the desired virtual view. I also quantify the capabilities of a virtual camera rendered from a camera array in terms of the range of motion, range of rotation, and effective resolution. I compare these results to other configurations. From this analysis I provide a method for camera array designers to select and configure cameras to meet desired specifications. I demonstrate the system and the conclusions of the analysis with a number of examples that exploit dynamic light fields., by Jason Chieh-Sheng Yang., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002., Includes bibliographical references (p. 157-163)., Computer graphics researchers recently have turned to image-based rendering to achieve the goal of photorealistic graphics. Instead of constructing a scene with millions of polygons, the scene is represented by a collection of photographs along with a greatly simplified geometric model. This simple representation allows traditional light transport simulations to be replaced with basic image-processing routines that combine multiple images together to produce never-before-seen images from new vantage points. This thesis presents a new image-based rendering algorithm called unstructured lumigraph rendering (ULR). ULR is an image-based rendering algorithm that is specifically designed to work with unstructured (i.e., irregularly arranged) collections of images. The algorithm is unique in that it is capable of using any amount of geometric or image information that is available about a scene. Specifically, the research in this thesis makes the following contributions: * An enumeration of image-based rendering properties that an ideal algorithm should attempt to satisfy. An algorithm that satisfies these properties should work as well as possible with any configuration of input images or geometric knowledge. * An optimal formulation of the basic image-based rendering problem, the solution to which is designed to satisfy the aforementioned properties. * The unstructured lumigraph rendering algorithm, which is an efficient approximation to the optimal image-based rendering solution. * A non-metric ULR algorithm, which generalizes the basic ULR algorithm to work with uncalibrated images. * A time-dependent ULR algorithm, which generalizes the basic ULR algorithm to work with time-dependent data., by Christopher James Buehler., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005., Includes bibliographical references (p. 153-158)., I present the design and analysis of a two-dimensional camera array for virtual studio applications. It is possible to substitute conventional cameras and motion control devices with a real-time, light field camera array. I discuss a variety of camera architectures and describe a prototype system based on the "finite-viewpoints" design that allows multiple viewers to navigate virtual cameras in a dynamically changing light field captured in real time. The light field camera consists of 64 commodity video cameras connected to off-the-shelf computers. I employ a distributed rendering algorithm that overcomes the data bandwidth problems inherent in capturing light fields by selectively transmitting only those portions of the video streams that contribute to the desired virtual view. I also quantify the capabilities of a virtual camera rendered from a camera array in terms of the range of motion, range of rotation, and effective resolution. I compare these results to other configurations. From this analysis I provide a method for camera array designers to select and configure cameras to meet desired specifications. I demonstrate the system and the conclusions of the analysis with a number of examples that exploit dynamic light fields., by Jason Chieh-Sheng Yang., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002., Includes bibliographical references (p. 157-163)., Computer graphics researchers recently have turned to image-based rendering to achieve the goal of photorealistic graphics. Instead of constructing a scene with millions of polygons, the scene is represented by a collection of photographs along with a greatly simplified geometric model. This simple representation allows traditional light transport simulations to be replaced with basic image-processing routines that combine multiple images together to produce never-before-seen images from new vantage points. This thesis presents a new image-based rendering algorithm called unstructured lumigraph rendering (ULR). ULR is an image-based rendering algorithm that is specifically designed to work with unstructured (i.e., irregularly arranged) collections of images. The algorithm is unique in that it is capable of using any amount of geometric or image information that is available about a scene. Specifically, the research in this thesis makes the following contributions: * An enumeration of image-based rendering properties that an ideal algorithm should attempt to satisfy. An algorithm that satisfies these properties should work as well as possible with any configuration of input images or geometric knowledge. * An optimal formulation of the basic image-based rendering problem, the solution to which is designed to satisfy the aforementioned properties. * The unstructured lumigraph rendering algorithm, which is an efficient approximation to the optimal image-based rendering solution. * A non-metric ULR algorithm, which generalizes the basic ULR algorithm to work with uncalibrated images. * A time-dependent ULR algorithm, which generalizes the basic ULR algorithm to work with time-dependent data., by Christopher James Buehler., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005., Includes bibliographical references (p. 153-158)., I present the design and analysis of a two-dimensional camera array for virtual studio applications. It is possible to substitute conventional cameras and motion control devices with a real-time, light field camera array. I discuss a variety of camera architectures and describe a prototype system based on the "finite-viewpoints" design that allows multiple viewers to navigate virtual cameras in a dynamically changing light field captured in real time. The light field camera consists of 64 commodity video cameras connected to off-the-shelf computers. I employ a distributed rendering algorithm that overcomes the data bandwidth problems inherent in capturing light fields by selectively transmitting only those portions of the video streams that contribute to the desired virtual view. I also quantify the capabilities of a virtual camera rendered from a camera array in terms of the range of motion, range of rotation, and effective resolution. I compare these results to other configurations. From this analysis I provide a method for camera array designers to select and configure cameras to meet desired specifications. I demonstrate the system and the conclusions of the analysis with a number of examples that exploit dynamic light fields., by Jason Chieh-Sheng Yang., Ph.D.