JOURNAL OF MULTIMEDIA (JMM)
ISSN : 1796-2048
Volume : 2    Issue : 6    Date : November 2007

Contour Tracking of Targets with Large Aspect Change
Behzad Jamasbi, Seyed Ahmad Motamedi, and Alireza Behrad
Page(s): 7-14
Full Text:
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Abstract
In this paper we present a novel method for tracking contour of a moving rigid object in natural video
sequences from a mobile camera. While a mobile camera is keeping track of a moving target, any
change in relative orientation or position of the target and camera may cause a change in the view of
target captured by the camera. This is called the target aspect change and known as a challenge in
tracking. Especially, a large aspect change may reveal some previously hidden parts of the target,
and this is the case we have handled in our algorithm. In proposed contour tracking method the
motion model of the target is estimated using corner matching and LMedS statistical method. This
model is used together with an active contour (snake) to track the target efficiently. The snake we
propose is capable of swelling locally, so that it can swell and include newly appeared parts of the
target in case of a large aspect change. Detecting target newly appeared parts, is based on the fact
that a part of target should move consistently with other parts and inconsistently with the
background. When a new part is detected the nearby part of the snake is stimulated to swell. In this
way the snake will include any new part of the target revealed by a large aspect change. Several
experiments have been conducted to show the promise of proposed algorithm.

Index Terms
contour tracking, moving target, aspect change, active contour, corner matching