760808
Partial Observation vs. Blind Tracking through Occlusion
This paper presents a framework for multi-object t racking from a single fixed camera. The region-based representations of each object are tracked and p redicted using a Kalman filter. A scene model is created to help predict and interpret the occluded or exiting objects. Unlike the traditional blind tracking during occlusion, the object states are updated using partial observations whenever available. The observability of each object depends on the predictive measurement of the object, the foreground region measurement, and p erhaps the scene model. This makes the a lgorithm m ore robust i n terms of both qualitative a nd quantitative criteria.
7647514
Tracking football players with multiple cameras
A system is described for tracking the positions of football players during a match. The input is eight video streams from static cameras, each processed to generate measurements of the players for a multi view tracker. The single view processing includes foreground detection and a bounding box tracker designed to split measurements of merged players. In the multi-view process, the measurements, each from a different camera and matched to the same player, are fused into an overall measurement which is then used in the estimate updating. Results are demonstrated on real data.
16235334
Illumination-Invariant Motion Detection Using Colour Mixture Models
This paper tackles the problem of robust change detection in image sequences from static cameras. Motion cues are detected using frame differencing with an adaptive background estimation modelled by a mixture of Gaussians. Illumination invariance and elimination or detection of shadows is achieved by using a colour chromaticity representation of the image data. The combination of the colourand intensity-based models results in some promising applications.
53245552
Simultaneous shield insertion and net ordering for capacitive and inductive coupling minimization
In this article, we first show that existing net ordering formulations to minimize noise are no longer sufficient with the presence of inductive noise, and shield insertion is needed to minimize inductive noise. Using a Keff model as the figure of merit for inductive coupling, we then formulate two simultaneous shield insertion and net ordering (SINO) problems: the optimal SINO/NF problem to find a minimal area SINO solution that is free of capacitive and inductive noise, and the optimal SINO/NB problem to find a minimal area SINO solution that is free of capacitive noise and is under the given inductive noise bound. We reveal that both optimal SINO problems are NP-hard, and propose effective approximate algorithms for the two problems. Experiments show that our SINO/NB algorithm uses from 51p to 82p fewer shields compared to uniform shield insertion and net ordering (US + NO), and uses from 4p to 47p fewer shields compared to separated net ordering and shield insertion (NO + SI). Furthermore, the SINO/NB solutions under practical noise bounds use from 38p to 61p fewer shields compared to SINO/NF solutions, and use up to 36p fewer shields compared to the theoretical lower bound for optimal SINO/NF solutions. Moreover, we show that the Keff model has a high fidelity versus the noise voltage computed using accurate RLC circuit models and SPICE simulations. To the best of our knowledge, it is the first work that presents an in-depth study on the automatic layout optimization of multiple nets to minimize both capacitive and inductive noise.
1185541
A serializability violation detector for shared-memory server programs
We aim to improve reliability of multithreaded programs by proposing a dynamic detector that detects potentially erroneous program executions and their causes. We design and evaluate a Serializability Violation Detector (SVD) that has two unique goals: (I) triggering automatic recovery from erroneous executions using backward error recovery (BER), or simply alerting users that a software error may have occurred; and (II) helping debug programs by revealing causes of error symptoms.Two properties of SVD help in achieving these goals. First, to detect only erroneous executions, SVD checks serializability of atomic regions, which are code regions that need to be executed atomically. Second, to improve usability, SVD does not require a priori annotations of atomic regions; instead, SVD approximates them using a heuristic. Experimental results on three widely-used multithreaded server programs show that SVD finds real bugs and reports modest false positives. The goal of this paper is to develop a detector suitable for (I) BER-based avoidance of erroneous program executions; and (II) alerting users as software errors occur. We argue that such a detector should have the following two properties.
206570343
Vertex-Primitive Graphs of Order a Product of Two Distinct Primes
Abstract Let k and p be odd primes with k p . All vertex-primitive graphs of order kp are classified, and those which are symmetric, or are edge-transitive but not symmetric. or are not Cayley graphs are identified. In addition, a classification is given of all vertex-primitive, edge-transitive lantisymmetric) directed graphs or order kp . The classification of the vertex-primitive symmetric graphs of order kp is used by the authors and others to complete the classification of symmetric graphs or order kp . The classification of the vertex-primitive non-Cayley graphs of order kp is used by B.D. McKay and the first author in an investigation of vertex-transitive non-Cayley graphs.
1797921
Arc-transitive circulant digraphs of odd prime-power order
In this paper, the full automorphism group of a circulant digraph of prime-power order is investigated, and as a result, a complete classification of arc-transitive circulant graphs of odd prime-power order is given.
19879470
The multiscale medial properties of interfering image structures
The multiscale medial axis (MMA) is a robust shape representation in analysing objects in greylevel images. It is computed as ridges in the medialness scale-space of an image. In this paper the multiscale medial properties of overlapping objects are investigated, the result of which is novel to the community in that the existing studies only concentrated on isolated objects. To improve the distinguishability of these objects, a sliding window algorithm is proposed to detect locally optimal scale ridges in scale space. When used in the medialness scale-space of an image, this efficient method can extract a complete set of MMAs for interfering objects, in contrast with the globally optimal scale ridge definition which has been widely used. This is demonstrated in the applications in medical images.