W4S: A real-time system for detecting and tracking people in 2 1/2D

  • Ismail Haritaoglu
  • David Harwood
  • Larry S. Davis
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1406)


W4S is a real time visual surveillance system for detecting and tracking people and monitoring their activities in an outdoor environment by integrating realtime stereo computation into an intensitybased detection and tracking system. Unlike many systems for tracking people, W4S makes no use of color cues. Instead, W4S employs a combination of stereo, shape analysis and tracking to locate people and their parts (head, hands, feet, torso) and create models of people's appearance so that they can be tracked through interactions such as occlusions. W4S is capable of simultaneously tracking multiple people even with occlusion. It runs at 5–20 Hz for 320×120 resolution images on a dual-pentium 200 PC.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • Ismail Haritaoglu
    • 1
  • David Harwood
    • 1
  • Larry S. Davis
    • 1
  1. 1.Computer Vision LaboratoryUniversity of MarylandCollege ParkUSA

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