Continuous Surface Reconstruction from a Gradient Field Without Discrete Enforcement of Integrability

MPhil Thesis Defence


Title: "Continuous Surface Reconstruction from a Gradient Field Without
Discrete Enforcement of Integrability"

By

Mr. Heung-Sun Ng


Abstract

Existing surface reconstruction algorithms taking a gradient field as
input enforce the integrability constraint. While enforcing integrability
allows the subsequent integration to produce surface heights, current
algorithms suffer from the one or more of following disadvantages: they
can only handle dense per-pixel gradients, smooth out sharp features in a
non-integrable field, or produce severe surface distortion. In this
thesis, we present a method which does not based on integrability
enforcement, and reconstructs a 3D continuous surface from a gradient
field which can be dense or sparse. The key of our approach is the use of
kernel basis functions, which transfers the continuous surface
reconstruction problem into high dimensional space where a closed-form
solution exists. This leads to a neat and straightforward implementation
while producing better results than traditional techniques. In particular,
the use of kernel functions as basis functions to represent a continuous
surface avoids unnecessary discretization and finite approximation, both
will lead to surface distortion, which are typical problems arising from
the use of Fourier or Wavelet bases widely adopted by previous
representative approaches. We perform exhaustive comparison with classical
and recent methods on benchmark and challenging data sets to demonstrate
that our method produces accurate surface reconstruction, while preserving
salient features and robust to noise.


Date:				Friday, 9 May 2008

Time:				5:00p.m.-7:00p.m.

Venue:				Room 3304
				Lifts 17-18

Committee Members:		Dr. Chi-Keung Tang (Supervisor)
				Dr. Huamin Qu (Chairperson)
				Dr. Philip Fu


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