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In this paper, we present a review of existing techniques and systems for tracking multiple occluding objects using one or more cameras. Following a formulation of the occlusion problem, we divide these techniques into two groups: merge-split (MS) approaches and straight-through (ST) approaches. Then, we consider tracking in ball game applications, with(More)
This article presents a modular architecture for multi-camera tracking in the context of sports broadcasting. For each video stream, a geometrical module continuously performs the image-to-model homography estimation. A local-feature based tracking module tracks the players in each view. A supervisor module collects, associates and fuses the data provided(More)
We first generalize the concept of clutter power spectrum locus so that it can be applied to arbitrary antenna arrays. This locus is a curve in the 4D space of the Doppler frequency and the 3 spatial frequencies. This generalization is valid for both monostatic and bistatic radar configurations. We show that the customary clutter power spectrum locus(More)
Edges are a fundamental clue for analyzing, interpreting, and understanding 3D scenes: they describe objects boundaries. Available edge detection methods are not suited for 3D cameras such as the Kinect or a time-of-flight camera: they are slow and do not take into consideration the characteristics of the cameras. In this paper, we present a fast jump edge(More)
The application of adaptive (i.e., data-dependent) mathematical morphology techniques to range imagery, i.e., the use of structuring elements (SEs) that automatically adjust to the gray-scale values in a range image in order to deal with features of known physical sizes, is discussed. The technique is applicable to any type of image for which the distance(More)
This paper presents a new approach for tracking objects in complex situations such as people in a crowd or players on a soccer field. Each object in the image is represented by several interest points (IPs). These IPs are obtained using a color version of the Harris IP detector. Each IP is characterized by the local appearance (chromatic first-order local(More)
Outcomes for neurosurgery patients can be improved by enhancing intraoperative navigation and guidance. Current navigation systems do not accurately account for intraoperative brain deformation. So far, most studies of brain deformation have focused on brain shift, whereas this paper focuses on the brain deformation due to retraction. The heart of our(More)
We introduce a new, efficient approach for modelling the deformation of organs following surgical cuts, retractions, and resections. It uses the extended finite element method (XFEM), recently developed in " fracture mechanics " for dealing with cracks in mechanical parts. XFEM eliminates the computationally-expensive remeshing that would be required if the(More)
This article focuses on the field-to-image registration for TV sports-related image processing through basic geometrical reasoning. We propose a robust automatic line-based method that can cope with imprecisions in the line detection steps through a hypothesis generation/pruning paradigm where the number of hypotheses is reduced by using the vanishing(More)
We address the problem of detecting slow-moving targets using a space-time adaptive processing (STAP) radar. The construction of optimum weights at each range implies the estimation of the clutter covariance matrix. This is typically done by straight averaging of neighboring data snapshots. The range-dependence of these snapshots generally results in poor(More)