We present a template-based approach to detecting human silhouettes in a specific walking pose. Our templates consist of short sequences of 2D silhouettes obtained from motion capture data. This lets us incorporate motion information into them and helps distinguish actual people who move in a predictable way from static objects whose outlines roughly resemble those of humans. Moreover, during t...

This paper presents a system to track moving humans in an indoor environment. We propose a cooperative approach of monocular camera and omnidirectional camera to the problem of finding humans by a mobile robot. A cooperation of fixed and moving platforms is proposed for this approach, which features background subtraction, pixel classification, color blob merging, color blob relation and segmen...

With computer vision the problem of speed comes up quite a bit. Images typically only contain a small amount of relevant information which needs to be processed. To help limit the information to be processed a method of pulling out the relevant information is needed. Background subtraction is an often used method to limit the information to be processed, since the background does not contain an...

This paper presents an architecture for sensor based, distributed, automated scene surveillance. The goal of the work is to employ wireless visual sensors, scattered in an area, for detection and tracking of objects of interest and their movements through application of agents. The architecture consists of several units known as Object Processing Units that are wirelessly connected in a cluster...

Background maintenance is a frequent element of video surveillance systems. We develop Wallflower, a threecomponent system for background maintenance: the pixellevel component performs Wiener filtering to make probabilistic predictions of the expected background; the region-level component fills in homogeneous regions of foreground objects; and the frame-level component detects sudden, global c...

PTZ cameras have the ability to cover wide areas with an adapted resolution. In this article we propose a background subtraction algorithm suitable for a PTZ camera performing a guard tour. It relies on the estimation of a probability density function based on the matching of keypoints between the background and the current image. Its main interest consists in the resulting robustness to sudden...

Online video lectures are becoming commonplace in higher education. One problem is that the instructor might block what he has written on the board. In our project, we reconstruct the online lecture video so that the information on the whiteboard is always available to the viewers. The background subtraction, object tracking, and object replacement technique have been used to reconstruct the mo...

We present a model-based method for accurate extraction of pedestrian silhouettes from video sequences. Our approach is based on two assumptions, 1) there is a common appearance to all pedestrians, and 2) each individual looks like him/herself over a short amount of time. These assumptions allow us to learn pedestrian models that encompass both a pedestrian population appearance and the individ...

In this paper, we present a multisensor surveillance system that consists of an optical sensor and an infrared sensor. In this system, a background subtraction method based on zero-order statistics is utilized for the moving object segmentation. Additionally, we propose a generic approach to simultaneous object tracking and multisensor image registration. An efficient face detection system is s...

A validity of a recent estimate of an upper limit of charm production in central Pb+Pb collisions at 158 A·GeV is critically discussed. Within a simple model we study properties of the background subtraction procedure used for an extraction of the charm signal from the analysis of dilepton spectra. We demonstrate that a production asymmetry between positively and negatively charged background m...