Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
Articles 1 - 3 of 3
Full-Text Articles in Physical Sciences and Mathematics
Image Magnification Using Level-Set Reconstruction, Bryan S. Morse, Duane Schwartzwald
Image Magnification Using Level-Set Reconstruction, Bryan S. Morse, Duane Schwartzwald
Faculty Publications
Image magnification is a common problem in imaging applications, requiring interpolation to “read between the pixels”. Although many magnification/interpolation algorithms have been proposed in the literature, all methods must suffer to some degree the effects of impefect reconstruction―false high-frequency content introduced by the underlying original sampling. Most often, these effects manifest themselves as jagged contours in the image. This paper presents a method for constrained smoothing of such artifacts that attempts to produce smooth reconstructions of the image’s level curves while still maintaining image fidelity. This is similar to other iterative reconstruction algorithms and to Bayesian restoration techniques, but instead …
Sew Representation For Low Rate Wi Coding, J. Lukasiak, I. S. Burnett
Sew Representation For Low Rate Wi Coding, J. Lukasiak, I. S. Burnett
Faculty of Informatics - Papers (Archive)
This paper considers low-rate waveform interpolation (WI) coding. It compares the existing, common slowly evolving waveform (SEW) quantisation scheme with two new schemes for representing and quantising the SEW. The first scheme uses a minimum phase estimate to reconstruct the SEW whilst the second scheme uses a pulse model whose parameters are implicitly transmitted in the quantised rapidly evolving waveform (REW). These new schemes maintain or reduce the bit rate required for transmission of the SEW. Results indicate that, for low rate WI coding, necessarily coarse SEW magnitude spectrum quantisation limits the contribution of the SEW to perceptual quality. Perceptual …
Interpolating Implicit Surfaces From Scattered Surface Data Using Compactly Supported Radial Basis Functions, Bryan S. Morse, David T. Chen, Penny Rheingans, Kalpathi Subramanian, Terry S. Yoo
Interpolating Implicit Surfaces From Scattered Surface Data Using Compactly Supported Radial Basis Functions, Bryan S. Morse, David T. Chen, Penny Rheingans, Kalpathi Subramanian, Terry S. Yoo
Faculty Publications
We describe algebraic methods for creating implicit surfaces using linear combinations of radial basis interpolants to form complex models from scattered surface points. Shapes with arbitrary topology are easily represented without the usual interpolation or aliasing errors arising from discrete sampling. These methods were first applied to implicit surfaces by Savchenko, et al. and later developed independently by Turk and O'Brien as a means of performing shape interpolation. Earlier approaches were limited as a modeling mechanism because of the order of the computational complexity involved. We explore and extend these implicit interpolating methods to make them suitable for systems of …