title: An Efficient Object Tracking Method on Quad-/Oc-Trees.
abstract: We introduce a fast error-free tracking method applicable to sequences of two and three dimensional images. The core idea is to use Quadtree (resp. Octree) data structures for representing the spatial discretization of an image in two (resp. three) spatial dimensions. This representation enables one to merge into large computational cells the regions that can be faithfully described with such a coarse representation, thus significantly reducing the total number of degrees of freedom that are processed, without compromising accuracy. This encoding is particularly effective in the case of algorithms based on moving fronts, since the adaptive refinement provides a natural means to focus the processing resources on information near the moving front. In this paper, we use an existing contour based tracker and reformulate it to the case of Quad-/Oc-tree data structures. Relevant mathematical assumptions and derivations are presented for this purpose. We then demonstrate that, on standard bio-medical image sequences, a speed up of 5X is easily achieved in 2D and about 10X in 3D.
authors.affiliation: Department of Mechanical Engineering, University of California Santa Barbara, Santa Barbara, CA 93106-5070, United States of America.
authors.forename: Magda
authors.initials: M
authors.lastname: Przybylowski
authors.affiliation: Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, CA 93106-5110, United States of America.
authors.forename: Pratim
authors.initials: P
authors.lastname: Ghosh
authors.affiliation: Department of Computer Science, University of California Santa Barbara, Santa Barbara, CA 93106-5110, United States of America.|Department of Mechanical Engineering, University of California Santa Barbara, Santa Barbara, CA 93106-5070, United States of America.
authors.forename: Frederic
authors.initials: F
authors.lastname: Gibou
mesh_terms: D000465:Algorithms; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000191:economics / Q000379:methods*; D009038:Motion