|Department of Engineering|
|University of Cambridge > Engineering Department > Machine Intelligence Lab|
IMAGE DIVERGENCE AND DEFORMATION FROM CLOSED CURVES.
Roberto Cipolla and Andrew Blake
This paper describes a novel method to measure the differential invariants of the image velocity field from the integral of normal image velocities around image contours. This is equivalent to measuring the temporal changes in the area of a closed contour. This avoids having to recover a dense image velocity field and taking partial derivatives. It also does not require point or line correspondences. Moreover integration provides some immunity to image measurement noise.
It is shown how an active observer making small, deliberate motions can use the estimates of the divergence and deformation of the image velocity field to determine the object surface orientation and time to contact. The results of real-time experiments are presented in which arbitrary image shapes are tracked using B-spline snakes and the invariants are computed efficiently as closed-form functions of the B-spline control points. This information is used to guide a robot manipulator in obstacle collision avoidance, object manipulation and navigation.
If you have difficulty viewing files that end
which are gzip compressed, then you may be able to find
tools to uncompress them at the gzip
If you have difficulty viewing files that are in PostScript, (ending
'.ps.gz'), then you may be able to
find tools to view them at
We have attempted to provide automatically generated PDF copies of documents for which only PostScript versions have previously been available. These are clearly marked in the database - due to the nature of the automatic conversion process, they are likely to be badly aliased when viewed at default resolution on screen by acroread.
|| Search | CUED | Cambridge University ||
2005 Cambridge University Engineering Dept
Information provided by milab-maintainer