MOTION ESTIMATION BASED ON AFFINE
MOMENT INVARIANTS

G. Tzanetakis, M. Traka, and G. Tziritas
Institute of Computer Science  FORTH,
P.O. Box 1385, 711 10 Heraklion, Greece
and
Department of Computer Science, University of Crete
P.O. Box 1470, Heraklion, Greece
Email: ftziritasg@csd.uch.gr

ABSTRACT
A method is proposed for parametric motion estimation
of an image region. It is assumed that the region considered 
undergoes an affine transformation, which means
that the motion is composed of a translation and a pure
affine function of pixel coordinates. The solution of the
object correspondence problem is assumed to be known.
The estimation of the six motion parameters is based on
the moments of the corresponding image regions. Moments 
up to order three are needed. For the motion
computation each region is transformed to a standard
position which is defined using affine invariants. The
result of motion estimation is checked in the construction 
of a mosaic image.



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