Published papers about

Observation of Human Activity

by James L. Crowley and co-authors


We introduce a modular tracker architecture that combines the advantages of several simple and rapidly performing tracking algorithms. Robust tracking is facilitated by frame-rate or near-frame-rate processing. A Kalman filter is used to integrate tracking results across detection modules and over time. Processing regions are smoothly localized by weighting with a Gaussian that is dimensioned according to the target sizes and uncertainties estimated by the Kalman filter. From this Gaussian mask, Gaussian approximations of known nearby targets are subtracted to allow individual tracking of interacting targets, that can be merged and split based on Mahalanobis distances and a robust version of connected components. The result is an adaptive tracker that can robustly track at video frame rates several targets, each of which corresponds to one or more individual objects. Its performance degrades gracefully with increased system load.


  1. J. L. Crowley, "Situation Models for Observing Human Activity" ACM Queue Magazine, May 2006.
  2. J. L. Crowley, "Context Aware Observation of Human Activity", PSIPS 2004, Oulu, Finland, June 2004.
  3. J. L. Crowley, "Context Driven Observation of Human Activity", EUSAI03, European Symposium on Ambient Intelligence, Amsterdam, 3-5 November 2003.
  4. J. L. Crowley and P. Reignier, Dynamic Composition of Process Federations for Context Aware Perception of Human Activity, KIMAS’03, International Conference on Integration of Knowledge Intensive Multi-Agent Systems,1-3 October 2003, Cambridge MA, USA
  5. J. L. Crowley, J. Coutaz, G. Rey and P. Reignier, "Perceptual Components for Context Aware Computing", UBICOMP 2002, International Conference on Ubiquitous Computing, Goteborg, Sweden, September 2002.
  6. J. L. Crowley, "Context Aware Observation of Human Activities", ICME-2002, IEEE International Conference on Multimedia and Expo, Lausanne, Aug 2002.
  7. J. Piater and J. Crowley, "Event-based Activity Analysis in Live Video using a Generic Object Tracker", Performance Evaluation for Tracking and Surveillance, PETS-2002, Copenhagen, June 2002.
  8. J. Piater and J. L. Crowley, "Multi-Modal Tracking of Interacting Targets Using Gaussian Approximations", Performance Evaluation for Tracking and Surveillance, PETS-2001, Kauai, Dec 2001.
  9. K. Schwerdt, D. Hall, J. L. Crowley, "Visual Recognition of Emotional States", The Third International Conference on Multimodal Interfaces, ICMI-2000, Beijing China, 14-16 October 2000.
  10. O. Chomat, J. Martin, and J. L. Crowley, "A Probabilistic Sensor for the Perception and Recognition of Activities", 6th European Conference on Computer Vision, Springer Verlag, Dublin, pp 487-506, June 2000.
  11. O. Chomat and J. L. Crowley, "A Probabilistic Sensor for the Perception of Activities", 4th IEEE International Conference on Automatic Face and Gesture Recognition", Grenoble, France, March 2000.
  12. W. Vieux, K. Schwerdt, and J. L. Crowley, "Face-tracking and coding for video compression", ICVS 99, International Conference on Vision Systems, Springer LNCS Series, Jan 1999
  13. O. Chomat and J. L. Crowley, "Probabilistic Recognition of Activity using Local Appearance", IEEE Conference on Computer Vision and Pattern Recognition, CVPR 99, Fort Collins, June 1999.
  14. J. Coutaz, F. Berard, E, Carraux and J. L. Crowley, "CoMedi: Using Computer Vision to Support Awareness and Privacy in Mediaspaces", ACM Conference on Computer Human Interaction, CHI 99, Pittsburgh, May 1999.
  15. J. Coutaz, F. Bérard, E. Carraux, et J. L. Crowley, "Early experiences with the mediaspace CoMedi", European Conference on Compuer Human Interaction, EHCI98, Crete, Sept. 1998.
  16. J. Coutaz, F. Berard and J. L. Crowley,"Coordination of Perceptual Processes for Computer Mediated Communication", FG96 - International Workshop on Face and Gesture Recognition, Vermont, Oct 1996.
  17. J. L. Crowley and J. Coutaz,"Vision for man-machine interaction", EHCI, Grand Targhee, August 1995.
  18. J. L. Crowley, "Integration and Control of Active Visual Processes", Workshop on Integration and Control for Computer Vision, IROS 95, Pittsburgh, August 1995.
  19. J. L. Crowley and J. M. Bedrune,"Integration and Control of Reactive Visual Processes", 1994 European Conference on Computer Vision, (ECCV-'94), Stockholm, may 94.