Paper Info
Title
Modeling corneal surfaces with rational functions for high-speed videokeratoscopy data compression.
Abstract
High-speed videokeratoscopy is an emerging technique that enables study of the corneal surface and tear-film dynamics. Unlike its static predecessor, this new technique results in a very large amount of digital data for which storage needs become significant. We aimed to design a compression technique that would use mathematical functions to parsimoniously fit corneal surface data with a minimum number of coefficients. Since the Zernike polynomial functions that have been traditionally used for modeling corneal surfaces may not necessarily correctly represent given corneal surface data in terms of its optical performance, we introduced the concept of Zernike polynomial-based rational functions. Modeling optimality criteria were employed in terms of both the rms surface error as well as the point spread function cross-correlation. The parameters of approximations were estimated using a nonlinear least-squares procedure based on the Levenberg-Marquardt algorithm. A large number of retrospective videokeratoscopic measurements were used to evaluate the performance of the proposed rational-function-based modeling approach. The results indicate that the rational functions almost always outperform the traditional Zernike polynomial approximations with the same number of coefficients.
Year
DOI
Venue
2009
10.1109/TBME.2008.2006019
IEEE Trans. Biomed. Engineering
Keywords
Field
DocType
zernike polynomials,rational functions
Computer vision,Function (mathematics),Nonlinear system,Polynomial,Computer science,Zernike polynomials,Artificial intelligence,Point spread function,Data compression,Rational function,Polynomial and rational function modeling
Journal
Volume
Issue
ISSN
56
2
1558-2531
Citations 
PageRank 
References 
2
0.81
5
Authors
3
Name
Order
Citations
PageRank
Martin Schneider19436.69
D Robert Iskander2144.27
Michael J. Collins316324.59