Virtual Post-its: Visual Label Extraction, Attachment, and Tracking for Teleconferencing

  • Indra Geys
  • Luc Van Gool
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2626)


We present a novel functionality for tele-conferencing and tele-teaching, coined ‘virtual post-IT’. A virtual label can be cut out of a scene or can have been determined beforehand. This label can then be virtually attached to either a part of the screen or to an object in the scene. When made part of the screen, it remains there as a reminder, e.g. to a complicated formula. When glued to an object, the label automatically follows it when the speaker moves the object around. This real-time tracking includes out-of-plane rotation and does not require any special markers. The selection of the pattern to be used as a label can be carried out on-line by the speaker, by simply encircling it with a laser pointer. S/he can also determine on which object it has to be glued and where. Also these commands are given through simple, intuitive motions with a laser pointer. As the encircling motion to cut out the label will be rather sloppy, the system autonomously determines a rectangle that encloses the data and that has edges which are aligned with the dominant directions of the environment (typically horizontal and vertical).


virtual and augmented reality visual annotation laser point detection real-time and markerless tracking affine invariant features 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Indra Geys
    • 1
  • Luc Van Gool
    • 1
    • 2
  1. 1.Katholieke Universiteit Leuven, ESAT/VISICSLeuvenBelgium
  2. 2.Swiss Federal Institute of Technology, ETH/BIWIZurichSwitzerland

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