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Physical Sciences and Mathematics Commons™

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Computer Sciences

Brigham Young University

Faculty Publications

Series

1998

Articles 1 - 8 of 8

Full-Text Articles in Physical Sciences and Mathematics

A Work Minimization Approach To Image Morphing, Peisheng Gao, Thomas W. Sederberg Dec 1998

A Work Minimization Approach To Image Morphing, Peisheng Gao, Thomas W. Sederberg

Faculty Publications

An algorithm is presented for morphing two images, often with little or no user interaction. For two similar images (such as different faces against a neutral background) the algorithm generally can create a pleasing morph completely automatically. The algorithm seeks the minimum work to deform one image into the other, where work is a function of the amount of warping and recoloration. A hierarchical method for finding a minimal work solution is invoked. Anchor point constraints are satisfied by imposing penalties on deformations that disobey these constraints. Good results can be obtained in less than ten seconds for 256 x …

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A Theory Of Satisficing Decisions And Control, Richard L. Frost, Michael A. Goodrich, Wynn C. Stirling Nov 1998

A Theory Of Satisficing Decisions And Control, Richard L. Frost, Michael A. Goodrich, Wynn C. Stirling

Faculty Publications

The existence of an optimal control policy and the techniques for finding it are grounded fundamentally in a global perspective. These techniques can be of limited value when the global behavior of the system is difficult to characterize, as it may be when the system is nonlinear, when the input is constrained, or when only partial information is available regarding system dynamics or the environment. Satisficing control theory is an alternative approach that is compatible with the limited rationality associated with such systems. This theory is extended by the introduction of the notion of strong satisficing to provide a systematic …

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Analysis Of The Interpolation Error Between Multiresolution Images, Bryan S. Morse Oct 1998

Analysis Of The Interpolation Error Between Multiresolution Images, Bryan S. Morse

Faculty Publications

Many rendering or image-analysis systems require calculation of versions of an image at lesser resolutions than the original. Because the filtering required to perform such calculations accurately cannot typically be done in real time, many systems use interpolation between images at precalculated resolutions. This discrete sampling of the scale component of multiresolution image spaces is analogous to spatial sampling in discrete images. This paper quantifies and bounds the error that can be introduced during such interpolation as a function of the scale-space sampling rate used. A method is presented that uses the diffusion equation to relate spatial derivatives to scale …

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Isophote-Based Interpolation, Bryan S. Morse, Duane Schwartzwald Oct 1998

Isophote-Based Interpolation, Bryan S. Morse, Duane Schwartzwald

Faculty Publications

Standard methods for image interpolation are based on smoothly fitting the image intensity surface. Recent edge-directed interpolation methods add limited geometric information (edge maps) to build more accurate and visually appealing interpolations at key contours in the image. This paper presents a method for geometry-based interpolation that smoothly fits the isophote (intensity level curve) contours at all points in the image rather than just at selected contours. By using level set methods for curve evolution, no explicit extraction or representation of these contours is required (unlike earlier edge-directed methods). The method uses existing interpolation techniques as an initial approximation and …

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Optimal Control Using A Neural/Evolutionary Hybrid System, Tony R. Martinez, Dan A. Ventura May 1998

Optimal Control Using A Neural/Evolutionary Hybrid System, Tony R. Martinez, Dan A. Ventura

Faculty Publications

One of the biggest hurdles to developing neurocontrollers is the difficulty in establishing good training data for the neural network. We propose a hybrid approach to the development of neurocontrollers that employs both evolutionary computation (EC) and neural networks (NN). EC is used to discover appropriate control actions for specific plant states. The survivors of the evolutionary process are used to construct a training set for the NN. The NN leams the training set, is able to generalize to new plant states, and is then used for neurocontrol. Thus the EC/NN approach combines the broad, parallel search of EC with …

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Constructing High Order Perceptrons With Genetic Algorithms, Timothy L. Andersen, Tony R. Martinez May 1998

Constructing High Order Perceptrons With Genetic Algorithms, Timothy L. Andersen, Tony R. Martinez

Faculty Publications

Constructive induction, which is defined to be the process of constructing new and useful features from existing ones, has been extensively studied in the literature. Since the number of possible high order features for any given learning problem is exponential in the number of input attributes (where the order of a feature is defined to be the number of attributes of which it is composed), the main problem faced by constructive induction is in selecting which features to use out of this exponentially large set of potential features. For any feature set chosen the desirable characteristics are minimality and generalization …

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Quantum Associative Memory With Exponential Capacity, Tony R. Martinez, Dan A. Ventura May 1998

Quantum Associative Memory With Exponential Capacity, Tony R. Martinez, Dan A. Ventura

Faculty Publications

Quantum computation uses microscopic quantum level effects to perrform computational tasks and has produced results that in some cases are exponentially faster than their classical counterparts by taking advantage of quantum parallelism. The unique characteristics of quantum theory may also be used to create a quantum associative memory with a capacity exponential in the number of neurons. This paper covers necessary high-level quantum mechanical ideas and introduces a simple quantum associative memory. Further, it provides discussion, empirical results and directions for future work.

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Breakpoint Skeletal Representation And Compression Of Document Images, William A. Barrett, Bryan S. Morse, Eric N. Mortensen Mar 1998

Breakpoint Skeletal Representation And Compression Of Document Images, William A. Barrett, Bryan S. Morse, Eric N. Mortensen

Faculty Publications

We present a new method for representation and (lossy) compression of bitonal document images. The technique extracts a skeletal medial axis from each object using a true Euclidean distance map of the image and then finds piecewise linear breakpoints in the skeleton to create a breakpoint skeletal representation, bps, (Fig. 1). The bps is encoded for each object as a set of triples {, <Δx2,Δy2,Δr2>, . . . <Δxn,Δyn,Δrn>} where contains the coordinate and distance (radius, r1) of the initial breakpoint from the closest point on the perimeter of the object and <Δxi,Δyi,Δri> represents the difference in location and radius between …

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