suter@latcs1.oz.au (David Suter) (04/04/91)
Technical Reports Available
Constraint Networks in Vision / Mixed Finite Elements
The author has investigated methods of using (Augmented) Lagrangian approaches
in various ways and in various problems in computer vision. These Augmented
Lagrangian approaches generalise many of the (Penalty) based approaches
used in most approaches. The major advances reulting from this approach are
1) The method can be used to reformulate visual reconstruction problems
in a manner that uses mixed finite elements and thus allows the use
of many computational schmes similar to those used in fluid mechanics.
The mixed finite elements are simpler than those finite elements used
previously.
2) The method lends itself to analog network solutions in a straightforward
way by employing the approach of Platt.
3) The realization of these analog networks in terms of transconductance
amplifiers (ala Mead) is simple - the networks produced by this method
are far simpler than those proposed by others (Harris).
Thus the work extends from problem reformulation right down to practical
implementation using either more standard digital techniques
(mixed finite element) or more exciting new analog networks (right down to the
transistor level). Some aspects of the work are to shortly appear at IJCNN-91
(Seattle July) but more information can be obtained by requesting some
or all of the following technichal reports:
1. D. Suter "Mixed Finite Element Formulation of Problems in Visual
Reconstruction" La Trobe University Technical Report No. 2/90,
Jan. 1990
This outlines the basic reformulation in Augmented Lagrangian terms and
shows how this generalizes approaches such as Horns recent shape from shading
approach. It also forshaddows the developments from here to analog networks
that generalize that of Harris.
2. D. Suter "Visual Reconstruction and Edge Detection Using Coupled
Deriviatives" La Trobe University Technical Report No. 7/90,
June 1990
This contains examples obtained using Platts constraint networks.
3. D. Mansor and D. Suter "An Analogue Circuit for First Order Regularization"
La Trobe University Technical Report No. 2/91,
March 1991
This shows how to realize the networks using transconductance amps and how
to simulate using SPICE (3b1).
Copies of these reports can be obtained by email or by writing to the author:
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David Suter ISD: +61 3 479-2393
Department of Computer Science
and Computer Engineering, STD: (03) 479-2393
La Trobe University, ACSnet: suter@latcs1.oz
Bundoora, CSnet: suter@latcs1.oz
Victoria, 3083, ARPA: suter%latcs1.oz@uunet.uu.net
Australia UUCP: ...!uunet!munnari!latcs1.oz!suter
TELEX: AA33143
FAX: 03 4785814